Epithelial ovarian cancer(EOC) is the leading cause of gynecological cancer-related mortality in the developed world. EOC is a heterogeneous disease represented by several histological and molecular subtypes. Therefor...Epithelial ovarian cancer(EOC) is the leading cause of gynecological cancer-related mortality in the developed world. EOC is a heterogeneous disease represented by several histological and molecular subtypes. Therefore, exploration of relevant preclinical animal models that consider the heterogenic nature of EOC is of great importance for the development of novel therapeutic strategies that can be translated clinically to combat this devastating disease. In this review, we discuss recent progress in the development of preclinical mouse models for EOC study as well as their advantages and limitations.展开更多
Age-related osteoporosis poses a significant challenge in musculoskeletal health;a condition characterized by reduced bone density and increased fracture susceptibility in older individuals necessitates a better under...Age-related osteoporosis poses a significant challenge in musculoskeletal health;a condition characterized by reduced bone density and increased fracture susceptibility in older individuals necessitates a better understanding of underlying molecular and cellular mechanisms.Emerging evidence suggests that osteocytes are the pivotal orchestrators of bone remodeling and represent novel therapeutic targets for age-related bone loss.Our study uses the prematurely aged PolgD257A/D257A(PolgA)mouse model to scrutinize age-and sex-related alterations in musculoskeletal health parameters(frailty,grip strength,gait data),bone and particularly the osteocyte lacuno-canalicular network(LCN).Moreover,a new quantitative in silico image analysis pipeline is used to evaluate the alterations in the osteocyte network with aging.Our findings underscore the pronounced degenerative changes in the musculoskeletal health parameters,bone,and osteocyte LCN in PolgA mice as early as 40 weeks,with more prominent alterations evident in aged males.Our findings suggest that the PolgA mouse model serves as a valuable model for studying the cellular mechanisms underlying age-related bone loss,given the comparable aging signs and age-related degeneration of the bone and the osteocyte network observed in naturally aging mice and elderly humans.展开更多
The discontinuation of denosumab[antibody targeting receptor activator of nuclear factor kappa B ligand(RANKL)]therapy may increase the risk of multiple vertebral fractures;however,the underlying pathophysiology is la...The discontinuation of denosumab[antibody targeting receptor activator of nuclear factor kappa B ligand(RANKL)]therapy may increase the risk of multiple vertebral fractures;however,the underlying pathophysiology is largely unknown.In patients who underwent discontinuation after multiple injections of denosumab,the levels of tartrate-resistant acid phosphatase 5b increased compared to pretreatment levels,indicating a phenomenon known as“overshoot.”The rate of decrease in bone mineral density during the withdrawal period was higher than the rate of decrease associated with aging,suggesting that the physiological bone metabolism had broken down.Overshoot and significant bone loss were also observed in mice receiving continuous administration of anti-RANKL antibody after treatment was interrupted,resembling the original pathology.In mice long out of overshoot,bone resorption recovered,but osteoblast numbers and bone formation remained markedly reduced.The bone marrow exhibited a significant reduction in stem cell(SC)antigen 1-and platelet-derived growth factor receptor alpha-expressing osteoblast progenitors(PαS cells)and alkaline phosphatase-positive early osteoblasts.Just before the overshoot phase,the osteoclast precursor cell population expands and RANKL-bearing extracellular vesicles(EVs)became abundant in the serum,leading to robust osteoclastogenesis after cessation of anti-RANKL treatment.Thus,accelerated bone resorption due to the accumulation of RANKLbearing EVs and long-term suppression of bone formation uncoupled from bone resorption leads to the severe bone loss characteristic of denosumab discontinuation.展开更多
Substantial evidence points to the early onset of peripheral inflammation in the development of Parkinson's disease(PD),supporting the“body-first”hypothesis.However,there remains a notable absence of PD-specific...Substantial evidence points to the early onset of peripheral inflammation in the development of Parkinson's disease(PD),supporting the“body-first”hypothesis.However,there remains a notable absence of PD-specific animal models induced by inflammatory cytokines.This study introduces a novel mouse model of PD driven by the proinflammatory cytokine CXCL1,identified in our previous research.The involvement of CXCL1 in PD pathogenesis was validated using subacute and chronic MPTP-induced mouse models.Based on these findings,2-month-old C57BL/6J mice were intravenously administered CXCL1(20 ng/kg/day)for 2 weeks(5 days per week),successfully replicating motor deficits and pathological alterations in the substantia nigra observed in the chronic MPTP model.These results demonstrate the potential of CXCL1-induced inflammation as a mechanism for PD modeling.The model revealed activation of the PPAR signaling pathway in CXCL1-mediated neuronal damage by CXCL1.Linoleic acid,a PPAR-γactivator,significantly mitigated MPTPand CXCL1-induced toxicity and reduced serum CXCL1levels.In addition,the CXCL1-injected mouse model shortened the timeline for developing chronic PD mouse model to 2 weeks,offering an efficient platform for studying inflammation-driven processes in PD.The findings provide critical insights into the inflammatory mechanisms underlying PD and identify promising therapeutic targets for intervention.展开更多
Alzheimer'sdisease(AD)isaprogressive neurodegenerative disorder characterized by cognitive impairment and distinct neuropathological features,including amyloid-βplaques,neurofibrillary tangles,and reactive astrog...Alzheimer'sdisease(AD)isaprogressive neurodegenerative disorder characterized by cognitive impairment and distinct neuropathological features,including amyloid-βplaques,neurofibrillary tangles,and reactive astrogliosis.Developing effective diagnostic,preventative,and therapeutic strategies for AD necessitates the establishment of animal models that accurately recapitulate the pathophysiological processes of the disease.Existing transgenic mouse models have significantly contributed to understanding AD pathology but often fail to replicate the complexity of human AD.Additionally,these models are limited in their ability to elucidate the interplay among amyloid-βplaques,neurofibrillary tangles,and reactive astrogliosis due to the absence of spatially and temporally specific genetic manipulation.In this study,we introduce a novel AD mouse model(APP/PS1-TauP301L-Adeno mice)designed to rapidly induce pathological symptoms and enhance understanding of AD mechanisms.Neurofibrillary tangles and severe reactive astrogliosis were induced by injecting AAVDJ-EF1a-hTauP301L-EGFP and Adeno-GFAP-GFP viruses into the hippocampi of 5-month-old APP/PS1 mice.Three months post-injection,these mice exhibited pronounced astrogliosis,substantial amyloid-βplaque accumulation,extensiveneurofibrillarytangles,accelerated neuronal loss,elevated astrocytic GABA levels,and significant spatial memory deficits.Notably,these pathological features were less severe in AAVTauP301L-expressing APP/PS1 mice without augmented reactive astrogliosis.These findings indicate an exacerbating role of severe reactive astrogliosis in amyloid-βplaque and neurofibrillary tangle-associated pathology.The APP/PS1-TauP301L-Adeno mouse model provides a valuable tool for advancing therapeutic research aimed at mitigating the progression of AD.展开更多
Background:Spinocerebellar ataxia type 2(SCA2)is a neurodegenerative disease marked by significant clinical and genetic heterogeneity,primarily caused by expanded CAG mutations in the ATXN2 gene.The unstable expansion...Background:Spinocerebellar ataxia type 2(SCA2)is a neurodegenerative disease marked by significant clinical and genetic heterogeneity,primarily caused by expanded CAG mutations in the ATXN2 gene.The unstable expansion of CAG repeats disrupts the genetic stability of animal models,which is detrimental to disease research.Methods:In this study,we established a mouse model in which CAG repeats do not undergo microsatellite instability(MSI)across generations.A humanized ATXN2 cDNA with four CAA interruptions within 73 CAG expansions was inserted into the Rosa26 locus of C57BL/6J mice.A 23 CAG control mouse model was also generated to verify ATXN2 integration and expression.Results:In our model,the number of CAG repeats remained stable during transmission,with no CAG repeat expansion observed in 64 parent-to-offspring transmissions.Compared with SCA2-Q23 mice,SCA2-Q73 mice exhibited progressive motor impairment,reduced Purkinje cell count and volume(indicative of cell atrophy),and muscle atrophy.These observations in the mice suggest that the behavioral and neuropathological phenotypes may reflect the features of SCA2 patients.RNA-seq analysis of the gastrocnemius muscle in SCA2-Q73 mice showed significant changes in muscle differentiation and development gene expression at 56 weeks,with no significant differences at 16 weeks compared to SCA2-Q23 mice.The expression level of the Myf6 gene significantly changed in the muscles of aged mice.Conclusion:In summary,the establishment of this model not only provides a stable animal model for studying CAG transmission in SCA2 but also indicates that the lack of long-term neural stimulation leads to muscle atrophy.展开更多
Background:Most mutations in the COL6A3 gene lead to collagen VI-related myopathies.This is due to a reduced expression or mislocalization of the COL6A3 protein.Therefore,studying the consequence of knocking out the C...Background:Most mutations in the COL6A3 gene lead to collagen VI-related myopathies.This is due to a reduced expression or mislocalization of the COL6A3 protein.Therefore,studying the consequence of knocking out the Col6a3 gene in mouse models is relevant,but the Col6a3 mouse models reported so far do not entirely abolish COL6A3 protein expression.Methods:Here,we present the development,validation and preliminary phenotypic characterization of a novel CRISPR-based knockout mouse model targeting Col6a3 exon 3(Col6a3^(d3/d3)).Results:In this mouse model,Col6a3 mRNA is still expressed at a similar level to wild-type littermates,although the expected protein is undetectable by mass spectrometry.Histological analysis of Col6a3^(d3/d3)quadriceps revealed an abnormally high frequency of muscle cells with internally nucleated muscle cells,consistent with a myopathy phenotype.Interestingly,Col6a3^(d3/d3)mice are smaller in size,with their fat,muscle,and bone kept proportional compared to wild-type littermates.Conclusions:In summary,we performed the validation and preliminary phenotypic characterization of a novel Col6a3 knockout mouse model that could be further characterized and used to study COL6A3 biology and model collagen VI-associated diseases.展开更多
Murine subarachnoid hemorrhage(SAH)induced using the filament perforation method is a useful in vivo experimental model to investigate the pathophysiological mechanisms in the brain underlying SAH.However,identifying ...Murine subarachnoid hemorrhage(SAH)induced using the filament perforation method is a useful in vivo experimental model to investigate the pathophysiological mechanisms in the brain underlying SAH.However,identifying mice with comorbid acute neurogenic pulmonary edema(NPE),a life-threatening systemic consequence often induced by SAH,in this model is difficult without histopathological investiga-tions.Herein,we present an imaging procedure involving dual-energy X-ray absorp-tiometry(DXA)to identify NPE in a murine model of SAH.We quantified the lung lean mass(LM)and compared the relationship between micro-computed tomography(CT)evidence of Hounsfield unit(HU)values and histopathological findings of PE.Of the 85 mice with successful induction of SAH by filament perforation,16(19%)had NPE,as verified by postmortem histology.The DXA-LM values correlate well with CT-HU levels(r=0.63,p<0.0001).Regarding the relationship between LM and HU in mice with post-SAH NPE,the LM was positively associated with HU values(r2=0.43;p=0.0056).A receiver operating characteristics curve of LM revealed a sensitivity of 87%and specificity of 57%for detecting PE,with a similar area under the curve as the HU(0.79±0.06 vs.0.84±0.07;p=0.21).These data suggest that confirming acute NPE using DXA-LM is a valuable method for selecting a clinically relevant murine NPE model that could be used in future experimental SAH studies.展开更多
Background:Rabies virus(RABV)-derived neuronal tracing tools are extensively applied in retrograde tracing due to their strict retrograde transsynaptic transfer property and low neurotoxicity.However,the RABV infectio...Background:Rabies virus(RABV)-derived neuronal tracing tools are extensively applied in retrograde tracing due to their strict retrograde transsynaptic transfer property and low neurotoxicity.However,the RABV infection and expression of fluorescence products would be gradually cleared while the infected neurons still survive,a phenomenon known as non-cytolytic immune clearance(NCLIC).This phenomenon introduced the risk of fluorescence loss and led to the omission of a subset of neurons that should be labeled,thereby interfering in the analysis of tracing results.Methods:To compensate for the fluorescence loss problem,in this study,we developed a novel marker footprints(MF)mouse,involving a Cre recombinase-dependent red fluorescent reporter system and systemic expression of glycoprotein(G)and ASLV-A receptor(TVA).Using this mouse model combined with the well-developed RABV-EnvA-ΔG-GFP-Cre viral tool,we developed a novel green-to-red spectral labeling strategy.Results:Neurons in the MF mouse could be co-labeled with green fluorescence from the very quick expression of the viral tool and with red fluorescence from the relatively slow expression of the neuron itself,so neurons undergoing NCLIC with green fluorescence loss could be relabeled red.Furthermore,newly infected neurons could be labeled green and other neurons could be labeled yellow due to the temporal expression difference between the two fluorescent proteins.Conclusions:This is the first polysynaptic retrograde tracing labeling strategy that could label neurons using spectral fluorescence colors with only one injection of the viral tool,enabling its application in recognizing the labeling sequence of neurons in brain regions and enhancing the spatiotemporal resolution of neuronal tracing.展开更多
Craniometaphyseal dysplasia(CMD),a rare craniotubular disorder,occurs in an autosomal dominant(AD)or autosomal recessive(AR)form.CMD is characterized by hyperostosis of craniofacial bones and metaphyseal flaring of lo...Craniometaphyseal dysplasia(CMD),a rare craniotubular disorder,occurs in an autosomal dominant(AD)or autosomal recessive(AR)form.CMD is characterized by hyperostosis of craniofacial bones and metaphyseal flaring of long bones.Many patients with CMD suffer from neurological symptoms.The pathogenesis of CMD is not fully understood.展开更多
Dear Editor,Crimean–Congo hemorrhagic fever(CCHF),caused by the CCHF virus(CCHFV),is a severe tick-borne illness with a wide geographical distribution,posing a significant threat with case fatality rates ranging from...Dear Editor,Crimean–Congo hemorrhagic fever(CCHF),caused by the CCHF virus(CCHFV),is a severe tick-borne illness with a wide geographical distribution,posing a significant threat with case fatality rates ranging from 5%to 70%(Hawman and Feldmann,2023).Due to the lack of approved vaccines and therapeutics,the World Health Organization(WHO)has listed CCHF as one of the priority diseases(Semper et al.,2024).CCHF initially presents as a nonspecific febrile illness,characterized by fever,malaise,myalgia,and nausea,which can rapidly progress to hemorrhagic disease.The hemorrhagic stage is particularly pronounced in severe cases,with rapid progression to disseminated intravascular coagulation(DIC),overt bleeding,kidney or liver failure,and shock(Frank et al.,2024).Up to date,there is an absence of a suitable animal model that can accurately mimic the coagulopathy and bleeding associated with CCHFV infection.Consequently,our understanding of the pathogenic mechanisms underlying these conditions remains limited(Rodriguez et al.,2022).展开更多
Background:The precise insertion of large DNA fragments(>3–5 kb)remains one of the key obstacles in establishment of genetically modified murine models.Methods:A 21 kb large DNA fragment containing three tandemly ...Background:The precise insertion of large DNA fragments(>3–5 kb)remains one of the key obstacles in establishment of genetically modified murine models.Methods:A 21 kb large DNA fragment containing three tandemly linked copies of the human HRAS gene was inserted into the genome of C57BL/6J mouse,generating a mouse model designated as KI.C57-ras(or named NF-h HRAS).Whole-genome sequencing and Sanger sequencing were utilized to it confirm precise insertion and copy number.The stability of transgene expression among different generations was verified from multiple aspects using by digital PCR,western blot and DNA sequencing.To assess tumor susceptibility in the mouse model,N-Nitroso-N-methylurea(MNU)was administered at a dosage of 75 mg/kg.Histopathological examinations were conducted using hematoxylin and eosin(H&E)staining.Results:The HRAS DNA fragment was inserted into mouse chromosome 15E1 site,locating between 80623202 bp and 80625020 bp.NF-h HRAS mice exhibited stable inheritance and displayed consistent phenotypes across individuals.Moreover,this mouse model exhibited a high susceptibility to carcinogens.Upon administration of MNU the earliest mortality onset was earlier than that of wild-type littermates(day 65 vs.day 78 for male and day 56 vs.day 84 for female).Notably,100%of the NF-h HRAS transgenic mice developed tumors,with approximately 84%of male NF-h HRAS mice exhibiting specific tumor types,such as squamous cell carcinoma or squamous cell papilloma,which was consistent with the previously reported carcinogenic rasH2 mouse model.The types of tumors and the target organs exhibited diversity in NFh HRAS mice,while the spontaneous tumor incidence remained low(1/50).Conclusions:The NF-h HRAS mice demonstrated excellent genetic stability,a reproducible phenotype,and high susceptibility to carcinogens,indicating their potential utility in non-clinical safety evaluations of drugs as per the S1B guidelines issued by the ICH(The International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use).展开更多
Genetically engineered mouse(GEM)models are commonly used in biomedical research.Generating GEMs involve complex set of experimental procedures requiring sophisticated equipment and highly skilled technical staff.Beca...Genetically engineered mouse(GEM)models are commonly used in biomedical research.Generating GEMs involve complex set of experimental procedures requiring sophisticated equipment and highly skilled technical staff.Because of these reasons,most research institutes set up centralized core facilities where custom GEMs are created for research groups.Researchers,on the other hand,when they begin thinking about generating GEMs for their research,several questions arise in their minds.For example,what type of model(s)would be best useful for my research,how do I design them,what are the latest technologies and tools available for developing my model(s),and finally how to breed GEMs in my research.As there are several considerations and options in mouse designs,and as it is an expensive and time-consuming endeavor,careful planning upfront can ensure the highest chance of success.In this article,we provide brief answers to several frequently asked questions that arise when researchers begin thinking about generating mouse model(s)for their work.展开更多
Parkinson's disease,the most common movement disorder,has a strong neuroinflammatory aspect.This is evident by increased pro-inflammatory cytokines in the serum,and the presence of activated microglial cells,and i...Parkinson's disease,the most common movement disorder,has a strong neuroinflammatory aspect.This is evident by increased pro-inflammatory cytokines in the serum,and the presence of activated microglial cells,and inflammatory cytokines in the substantia nigra of post-mortem brains as well as cerebrospinal fluid of Parkinson's disease patients.The central and peripheral neuroinflammatory aspects of Parkinson's disease can be investigated in vivo via administration of the inflammagen lipopolysaccharide,a component of the cell wall of gram-negative bacteria.In this mini-review,we will critically evaluate different routes of lipopolysaccharide administration(including intranasal systemic and ste reotasic),their relevance to clinical Parkinson's disease as well as the recent findings in lipopolysaccharide mouse models.We will also share our own expe riences with systemic and intrastriatal lipopolysaccharide models in C57BL/6 mice and will discuss the usefulness of lipopolysaccharide mouse models for future research in the field.展开更多
Klinefelter syndrome(KS)is one of the most frequent genetic abnormalities and the leading genetic cause of nonobstructive azoospermia.The breeding and study of KS mouse models are essential to advancing our knowledge ...Klinefelter syndrome(KS)is one of the most frequent genetic abnormalities and the leading genetic cause of nonobstructive azoospermia.The breeding and study of KS mouse models are essential to advancing our knowledge of the underlying pathological mechanism.Karyotyping and fluorescence in situ hybridization are reliable methods for identifying chromosomal contents.However,technical issues associated with these methods can decrease the efficiency of breeding KS mouse models and limit studies that require rapid identification of target mice.To overcome these limitations,we developed three polymerase chain reaction-based assays to measure specific genetic information,including presence or absence of the sex determining region of chromosome Y(Sry),copy number of amelogenin,X-linked(Amelx),and inactive X specific transcripts(Xist)levels.Through a combined analysis of the assay results,we can infer the karyotype of target mice.We confirmed the utility of our assays with the successful generation of KS mouse models.Our assays are rapid,inexpensive,high capacity,easy to perform,and only require small sample amounts.Therefore,they facilitate the breeding and study of KS mouse models and help advance our knowledge of the pathological mechanism underlying KS.展开更多
Background:It is well recognized that developing new animal models,refining the existing mouse models,and thoroughly characterizing their features are essential for gaining a deeper understanding of rosacea pathogenes...Background:It is well recognized that developing new animal models,refining the existing mouse models,and thoroughly characterizing their features are essential for gaining a deeper understanding of rosacea pathogenesis and for advancing therapeutic strategies in this direction.Accordingly,we aimed to characterize the pathological features of a long-term LL-37-induced mouse model of rosacea and to compare the disease manifestations and pathophysiological characteristics between short-term and long-term LL-37-induced models.A key focus was to investigate differential gene expression and the underlying mechanisms of immune system dysregulation in these models.Methods:We comparatively assessed skin lesion manifestations,the extent of inflammatory infiltration,sebaceous gland alterations,fibrosis,and angiogenesis in both models.Assessments were performed using photographic documentation,hematoxylin-eosin(HE)staining,Van Gieson's(VG)staining,immunohistochemistry,and Western blotting.Furthermore,we employed RNA sequencing to analyze differential gene expression in mouse skin.The RNA sequencing data were validated using immunofluorescence staining and Western blotting,with a specific focus on gene variations and mechanisms related to immune system dysregulation.Results:Mice subjected to long-term LL-37 induction developed rosacea-like pathological features,including angiogenesis,thickened skin tissue,and sebaceous gland hypertrophy.In the short-term LL-37-induced model,immune dysregulation primarily involved the innate immune response.However,long-term LL-37 induction resulted in significant activation of both innate and adaptive immune responses.Conclusion:The long-term LL-37-induced mouse model offers a valuable animal model for the detailed investigation of the pathological mechanisms driving moderate-to-severe rosacea with prolonged disease duration.Importantly,this model provides a significant experimental foundation for exploring the potential role of immune system dysregulation in rosacea pathogenesis.展开更多
[ Objective] The aim of this study is to construct the model for simple obesity induced by high-fat diet, which is closest to human obesity, laying a foundation for the studies of obesity related theories. [Method[ IC...[ Objective] The aim of this study is to construct the model for simple obesity induced by high-fat diet, which is closest to human obesity, laying a foundation for the studies of obesity related theories. [Method[ ICR and KM mice, half male and half female, were randomly divided into the high-fat diet experimental group and the normal diet control group based on body weights, and certain days later, body weight, Lee＇ s index, wet weight of adipose tissue, quantity of adipose cell in the same visual field and blood indices were measured. [Result]All indices mentioned a- bove of the female I CR mouse had significant statistical differences with those of the control group （P 〈 0.01 or P 〈 0.05）. [ Conclusion] To con- struct mouse nutritional obesity model successfully, different high-fat diets are required by different lines as well as different sexes in the same line.展开更多
Background:New variants of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continue to drive global epidemics and pose significant health risks.The pathogenicity of these variants evolves under immune press...Background:New variants of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continue to drive global epidemics and pose significant health risks.The pathogenicity of these variants evolves under immune pressure and host factors.Understanding these changes is crucial for epidemic control and variant research.Methods:Human angiotensin-converting enzyme 2(hACE2)transgenic mice were in-tranasally challenged with the original strain WH-09 and the variants Delta,Beta,and Omicron BA.1,while BALB/c mice were challenged with Omicron subvariants BA.5,BF.7,and XBB.1.To compare the pathogenicity differences among variants,we con-ducted a comprehensive analysis that included clinical symptom observation,meas-urement of viral loads in the trachea and lungs,evaluation of pulmonary pathology,analysis of immune cell infiltration,and quantification of cytokine levels.Results:In hACE2 mice,the Beta variant caused significant weight loss,severe lung inflammation,increased inflammatory and chemotactic factor secretion,greater mac-rophage and neutrophil infiltration in the lungs,and higher viral loads with prolonged shedding duration.In contrast,BA.1 showed a significant reduction in pathogenicity.The BA.5,BF.7,and XBB.1 variants were less pathogenic than the WH-09,Beta,and Delta variants when infected in BALB/c mice.This was evidenced by reduced weight loss,diminished pulmonary pathology,decreased secretion of inflammatory factors and chemokines,reduced macrophage and neutrophil infiltration,as well as lower viral loads in both the trachea and lungs.Conclusion:In hACE2 mice,the Omicron variant demonstrated the lowest pathogenic-ity,while the Beta variant exhibited the highest.Pathogenicity of the Delta variant was comparable to the original WH-09 strain.Among BALB/c mice,Omicron subvari-ants BA.5,BF.7,and XBB.1 showed no statistically significant differences in virulence.展开更多
基金supported by the US National Institutes of Health (R01CA160331, R01CA163377, R01CA202919,R01CA239128, P01AG031862, P50CA228991 to R.G.Z. and K99CA241395 to S.K.)US Department of Defense (OC180109 and OC190181 to R.G.Z.)+2 种基金The Honorable Tina Brozman Foundation for Ovarian Cancer Research (to R.G.Z.)Ovarian Cancer Research Alliance Collaborative Research Development Grant (to R.G.Z.)Core facilities support was provided by a Cancer Centre Support Grant(CA010815) to the Wistar Institute。
文摘Epithelial ovarian cancer(EOC) is the leading cause of gynecological cancer-related mortality in the developed world. EOC is a heterogeneous disease represented by several histological and molecular subtypes. Therefore, exploration of relevant preclinical animal models that consider the heterogenic nature of EOC is of great importance for the development of novel therapeutic strategies that can be translated clinically to combat this devastating disease. In this review, we discuss recent progress in the development of preclinical mouse models for EOC study as well as their advantages and limitations.
基金the European Research Council(ERC Advanced MechAGE-ERC-2016-ADG-741883)the Swiss National Science Foundation(no.188522).
文摘Age-related osteoporosis poses a significant challenge in musculoskeletal health;a condition characterized by reduced bone density and increased fracture susceptibility in older individuals necessitates a better understanding of underlying molecular and cellular mechanisms.Emerging evidence suggests that osteocytes are the pivotal orchestrators of bone remodeling and represent novel therapeutic targets for age-related bone loss.Our study uses the prematurely aged PolgD257A/D257A(PolgA)mouse model to scrutinize age-and sex-related alterations in musculoskeletal health parameters(frailty,grip strength,gait data),bone and particularly the osteocyte lacuno-canalicular network(LCN).Moreover,a new quantitative in silico image analysis pipeline is used to evaluate the alterations in the osteocyte network with aging.Our findings underscore the pronounced degenerative changes in the musculoskeletal health parameters,bone,and osteocyte LCN in PolgA mice as early as 40 weeks,with more prominent alterations evident in aged males.Our findings suggest that the PolgA mouse model serves as a valuable model for studying the cellular mechanisms underlying age-related bone loss,given the comparable aging signs and age-related degeneration of the bone and the osteocyte network observed in naturally aging mice and elderly humans.
文摘The discontinuation of denosumab[antibody targeting receptor activator of nuclear factor kappa B ligand(RANKL)]therapy may increase the risk of multiple vertebral fractures;however,the underlying pathophysiology is largely unknown.In patients who underwent discontinuation after multiple injections of denosumab,the levels of tartrate-resistant acid phosphatase 5b increased compared to pretreatment levels,indicating a phenomenon known as“overshoot.”The rate of decrease in bone mineral density during the withdrawal period was higher than the rate of decrease associated with aging,suggesting that the physiological bone metabolism had broken down.Overshoot and significant bone loss were also observed in mice receiving continuous administration of anti-RANKL antibody after treatment was interrupted,resembling the original pathology.In mice long out of overshoot,bone resorption recovered,but osteoblast numbers and bone formation remained markedly reduced.The bone marrow exhibited a significant reduction in stem cell(SC)antigen 1-and platelet-derived growth factor receptor alpha-expressing osteoblast progenitors(PαS cells)and alkaline phosphatase-positive early osteoblasts.Just before the overshoot phase,the osteoclast precursor cell population expands and RANKL-bearing extracellular vesicles(EVs)became abundant in the serum,leading to robust osteoclastogenesis after cessation of anti-RANKL treatment.Thus,accelerated bone resorption due to the accumulation of RANKLbearing EVs and long-term suppression of bone formation uncoupled from bone resorption leads to the severe bone loss characteristic of denosumab discontinuation.
基金supported by the National Natural Science Foundation of China (32471049,32170984,32471188,32200802)Natural Science Foundation of Shandong Province (ZR2023QH110)。
文摘Substantial evidence points to the early onset of peripheral inflammation in the development of Parkinson's disease(PD),supporting the“body-first”hypothesis.However,there remains a notable absence of PD-specific animal models induced by inflammatory cytokines.This study introduces a novel mouse model of PD driven by the proinflammatory cytokine CXCL1,identified in our previous research.The involvement of CXCL1 in PD pathogenesis was validated using subacute and chronic MPTP-induced mouse models.Based on these findings,2-month-old C57BL/6J mice were intravenously administered CXCL1(20 ng/kg/day)for 2 weeks(5 days per week),successfully replicating motor deficits and pathological alterations in the substantia nigra observed in the chronic MPTP model.These results demonstrate the potential of CXCL1-induced inflammation as a mechanism for PD modeling.The model revealed activation of the PPAR signaling pathway in CXCL1-mediated neuronal damage by CXCL1.Linoleic acid,a PPAR-γactivator,significantly mitigated MPTPand CXCL1-induced toxicity and reduced serum CXCL1levels.In addition,the CXCL1-injected mouse model shortened the timeline for developing chronic PD mouse model to 2 weeks,offering an efficient platform for studying inflammation-driven processes in PD.The findings provide critical insights into the inflammatory mechanisms underlying PD and identify promising therapeutic targets for intervention.
基金supported by the National Research Foundation of Korea (NRF)funded by the Ministry of Science,ICT&Future Planning (2022R1A2C2006229,2022R1A6A3A01086868)Korea Dementia Research Project through the Korea Dementia Research Center (KDRC)funded by the Ministry of Health&Welfare and Ministry of Science and ICT,Republic of Korea (RS-2024-00345328)KIST Institutional Grant (2E32851)。
文摘Alzheimer'sdisease(AD)isaprogressive neurodegenerative disorder characterized by cognitive impairment and distinct neuropathological features,including amyloid-βplaques,neurofibrillary tangles,and reactive astrogliosis.Developing effective diagnostic,preventative,and therapeutic strategies for AD necessitates the establishment of animal models that accurately recapitulate the pathophysiological processes of the disease.Existing transgenic mouse models have significantly contributed to understanding AD pathology but often fail to replicate the complexity of human AD.Additionally,these models are limited in their ability to elucidate the interplay among amyloid-βplaques,neurofibrillary tangles,and reactive astrogliosis due to the absence of spatially and temporally specific genetic manipulation.In this study,we introduce a novel AD mouse model(APP/PS1-TauP301L-Adeno mice)designed to rapidly induce pathological symptoms and enhance understanding of AD mechanisms.Neurofibrillary tangles and severe reactive astrogliosis were induced by injecting AAVDJ-EF1a-hTauP301L-EGFP and Adeno-GFAP-GFP viruses into the hippocampi of 5-month-old APP/PS1 mice.Three months post-injection,these mice exhibited pronounced astrogliosis,substantial amyloid-βplaque accumulation,extensiveneurofibrillarytangles,accelerated neuronal loss,elevated astrocytic GABA levels,and significant spatial memory deficits.Notably,these pathological features were less severe in AAVTauP301L-expressing APP/PS1 mice without augmented reactive astrogliosis.These findings indicate an exacerbating role of severe reactive astrogliosis in amyloid-βplaque and neurofibrillary tangle-associated pathology.The APP/PS1-TauP301L-Adeno mouse model provides a valuable tool for advancing therapeutic research aimed at mitigating the progression of AD.
基金CAMS Innovation Fund for Medical Sciences,Grant/Award Number:CIFMS,2021-I2M-1-024The Joint Fund for the Department of Science and Technology of Yunnan Province-Kunming Medical University,Grant/Award Number:202201AY070001-007+1 种基金Open Research Fund Project of Yunnan Provincial Key Laboratory of Pharmacology of Natural Medicines,Grant/Award Number:YKLPNP-G2403The Science and Technology Leading Talent Program of Yunnan Province,Grant/Award Number:202405AB350002。
文摘Background:Spinocerebellar ataxia type 2(SCA2)is a neurodegenerative disease marked by significant clinical and genetic heterogeneity,primarily caused by expanded CAG mutations in the ATXN2 gene.The unstable expansion of CAG repeats disrupts the genetic stability of animal models,which is detrimental to disease research.Methods:In this study,we established a mouse model in which CAG repeats do not undergo microsatellite instability(MSI)across generations.A humanized ATXN2 cDNA with four CAA interruptions within 73 CAG expansions was inserted into the Rosa26 locus of C57BL/6J mice.A 23 CAG control mouse model was also generated to verify ATXN2 integration and expression.Results:In our model,the number of CAG repeats remained stable during transmission,with no CAG repeat expansion observed in 64 parent-to-offspring transmissions.Compared with SCA2-Q23 mice,SCA2-Q73 mice exhibited progressive motor impairment,reduced Purkinje cell count and volume(indicative of cell atrophy),and muscle atrophy.These observations in the mice suggest that the behavioral and neuropathological phenotypes may reflect the features of SCA2 patients.RNA-seq analysis of the gastrocnemius muscle in SCA2-Q73 mice showed significant changes in muscle differentiation and development gene expression at 56 weeks,with no significant differences at 16 weeks compared to SCA2-Q23 mice.The expression level of the Myf6 gene significantly changed in the muscles of aged mice.Conclusion:In summary,the establishment of this model not only provides a stable animal model for studying CAG transmission in SCA2 but also indicates that the lack of long-term neural stimulation leads to muscle atrophy.
文摘Background:Most mutations in the COL6A3 gene lead to collagen VI-related myopathies.This is due to a reduced expression or mislocalization of the COL6A3 protein.Therefore,studying the consequence of knocking out the Col6a3 gene in mouse models is relevant,but the Col6a3 mouse models reported so far do not entirely abolish COL6A3 protein expression.Methods:Here,we present the development,validation and preliminary phenotypic characterization of a novel CRISPR-based knockout mouse model targeting Col6a3 exon 3(Col6a3^(d3/d3)).Results:In this mouse model,Col6a3 mRNA is still expressed at a similar level to wild-type littermates,although the expected protein is undetectable by mass spectrometry.Histological analysis of Col6a3^(d3/d3)quadriceps revealed an abnormally high frequency of muscle cells with internally nucleated muscle cells,consistent with a myopathy phenotype.Interestingly,Col6a3^(d3/d3)mice are smaller in size,with their fat,muscle,and bone kept proportional compared to wild-type littermates.Conclusions:In summary,we performed the validation and preliminary phenotypic characterization of a novel Col6a3 knockout mouse model that could be further characterized and used to study COL6A3 biology and model collagen VI-associated diseases.
基金supported by the Grants-in-Aid for Scientific Research from Japan Society for the Promotion of Science KAKENHI 22K09110.
文摘Murine subarachnoid hemorrhage(SAH)induced using the filament perforation method is a useful in vivo experimental model to investigate the pathophysiological mechanisms in the brain underlying SAH.However,identifying mice with comorbid acute neurogenic pulmonary edema(NPE),a life-threatening systemic consequence often induced by SAH,in this model is difficult without histopathological investiga-tions.Herein,we present an imaging procedure involving dual-energy X-ray absorp-tiometry(DXA)to identify NPE in a murine model of SAH.We quantified the lung lean mass(LM)and compared the relationship between micro-computed tomography(CT)evidence of Hounsfield unit(HU)values and histopathological findings of PE.Of the 85 mice with successful induction of SAH by filament perforation,16(19%)had NPE,as verified by postmortem histology.The DXA-LM values correlate well with CT-HU levels(r=0.63,p<0.0001).Regarding the relationship between LM and HU in mice with post-SAH NPE,the LM was positively associated with HU values(r2=0.43;p=0.0056).A receiver operating characteristics curve of LM revealed a sensitivity of 87%and specificity of 57%for detecting PE,with a similar area under the curve as the HU(0.79±0.06 vs.0.84±0.07;p=0.21).These data suggest that confirming acute NPE using DXA-LM is a valuable method for selecting a clinically relevant murine NPE model that could be used in future experimental SAH studies.
基金Hubei Natural Science Foundation of China,Grant/Award Number:2024AFB593。
文摘Background:Rabies virus(RABV)-derived neuronal tracing tools are extensively applied in retrograde tracing due to their strict retrograde transsynaptic transfer property and low neurotoxicity.However,the RABV infection and expression of fluorescence products would be gradually cleared while the infected neurons still survive,a phenomenon known as non-cytolytic immune clearance(NCLIC).This phenomenon introduced the risk of fluorescence loss and led to the omission of a subset of neurons that should be labeled,thereby interfering in the analysis of tracing results.Methods:To compensate for the fluorescence loss problem,in this study,we developed a novel marker footprints(MF)mouse,involving a Cre recombinase-dependent red fluorescent reporter system and systemic expression of glycoprotein(G)and ASLV-A receptor(TVA).Using this mouse model combined with the well-developed RABV-EnvA-ΔG-GFP-Cre viral tool,we developed a novel green-to-red spectral labeling strategy.Results:Neurons in the MF mouse could be co-labeled with green fluorescence from the very quick expression of the viral tool and with red fluorescence from the relatively slow expression of the neuron itself,so neurons undergoing NCLIC with green fluorescence loss could be relabeled red.Furthermore,newly infected neurons could be labeled green and other neurons could be labeled yellow due to the temporal expression difference between the two fluorescent proteins.Conclusions:This is the first polysynaptic retrograde tracing labeling strategy that could label neurons using spectral fluorescence colors with only one injection of the viral tool,enabling its application in recognizing the labeling sequence of neurons in brain regions and enhancing the spatiotemporal resolution of neuronal tracing.
基金supported by NIH/NIDCR grant R01DE025664 to IPC.
文摘Craniometaphyseal dysplasia(CMD),a rare craniotubular disorder,occurs in an autosomal dominant(AD)or autosomal recessive(AR)form.CMD is characterized by hyperostosis of craniofacial bones and metaphyseal flaring of long bones.Many patients with CMD suffer from neurological symptoms.The pathogenesis of CMD is not fully understood.
基金supported in part by grants from the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0490000 to Z.H.)National Key Research and Development Program(2021YFF0702002 to J.L.,2022YFC2303300 to Z.H.,and 2023YFC2305900 to M.W.)+3 种基金“Youth Commando”project(2023QNTJ-02 TO J.L.)Key Project(2024JZZD-02 to Z.H.)of State Key Laboratory of Virology and BiosafetyWuhan Institute of Virology,the National Natural Science Foundation of China(U22A20336 to Z.H.and Y.Z.)Wuhan Natural Science Foundation(202404071010067 to M.W.and 202404071010068 to J.L.).
文摘Dear Editor,Crimean–Congo hemorrhagic fever(CCHF),caused by the CCHF virus(CCHFV),is a severe tick-borne illness with a wide geographical distribution,posing a significant threat with case fatality rates ranging from 5%to 70%(Hawman and Feldmann,2023).Due to the lack of approved vaccines and therapeutics,the World Health Organization(WHO)has listed CCHF as one of the priority diseases(Semper et al.,2024).CCHF initially presents as a nonspecific febrile illness,characterized by fever,malaise,myalgia,and nausea,which can rapidly progress to hemorrhagic disease.The hemorrhagic stage is particularly pronounced in severe cases,with rapid progression to disseminated intravascular coagulation(DIC),overt bleeding,kidney or liver failure,and shock(Frank et al.,2024).Up to date,there is an absence of a suitable animal model that can accurately mimic the coagulopathy and bleeding associated with CCHFV infection.Consequently,our understanding of the pathogenic mechanisms underlying these conditions remains limited(Rodriguez et al.,2022).
基金National Key R&D Program of China,Grant/Award Number:2023YFC3402000National Institutes for Food and Drug Control,State Key Laboratory of Drug Regulatory Science,Grant/Award Number:2023SKLDRS0124。
文摘Background:The precise insertion of large DNA fragments(>3–5 kb)remains one of the key obstacles in establishment of genetically modified murine models.Methods:A 21 kb large DNA fragment containing three tandemly linked copies of the human HRAS gene was inserted into the genome of C57BL/6J mouse,generating a mouse model designated as KI.C57-ras(or named NF-h HRAS).Whole-genome sequencing and Sanger sequencing were utilized to it confirm precise insertion and copy number.The stability of transgene expression among different generations was verified from multiple aspects using by digital PCR,western blot and DNA sequencing.To assess tumor susceptibility in the mouse model,N-Nitroso-N-methylurea(MNU)was administered at a dosage of 75 mg/kg.Histopathological examinations were conducted using hematoxylin and eosin(H&E)staining.Results:The HRAS DNA fragment was inserted into mouse chromosome 15E1 site,locating between 80623202 bp and 80625020 bp.NF-h HRAS mice exhibited stable inheritance and displayed consistent phenotypes across individuals.Moreover,this mouse model exhibited a high susceptibility to carcinogens.Upon administration of MNU the earliest mortality onset was earlier than that of wild-type littermates(day 65 vs.day 78 for male and day 56 vs.day 84 for female).Notably,100%of the NF-h HRAS transgenic mice developed tumors,with approximately 84%of male NF-h HRAS mice exhibiting specific tumor types,such as squamous cell carcinoma or squamous cell papilloma,which was consistent with the previously reported carcinogenic rasH2 mouse model.The types of tumors and the target organs exhibited diversity in NFh HRAS mice,while the spontaneous tumor incidence remained low(1/50).Conclusions:The NF-h HRAS mice demonstrated excellent genetic stability,a reproducible phenotype,and high susceptibility to carcinogens,indicating their potential utility in non-clinical safety evaluations of drugs as per the S1B guidelines issued by the ICH(The International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use).
基金We thank D.D.Meigs(University of Nebraska Medical Center)and Tonya Cejka(freelance English editor)for editing assistance.C.B.G.is funded by NIH grants R35HG010719,R21GM129559,R21AI143394 and R21DA046831.M.O.is funded by 2016–2017 Tokai University School of Medicine Project Research,the Research Aid from the Institute of Medical Sciences in Tokai University,Grant-in-Aid for Scientific Research(25290035)from MEXTa Grant-in-Aid for Challenging Exploratory Research(15K14371)from JSPS.
文摘Genetically engineered mouse(GEM)models are commonly used in biomedical research.Generating GEMs involve complex set of experimental procedures requiring sophisticated equipment and highly skilled technical staff.Because of these reasons,most research institutes set up centralized core facilities where custom GEMs are created for research groups.Researchers,on the other hand,when they begin thinking about generating GEMs for their research,several questions arise in their minds.For example,what type of model(s)would be best useful for my research,how do I design them,what are the latest technologies and tools available for developing my model(s),and finally how to breed GEMs in my research.As there are several considerations and options in mouse designs,and as it is an expensive and time-consuming endeavor,careful planning upfront can ensure the highest chance of success.In this article,we provide brief answers to several frequently asked questions that arise when researchers begin thinking about generating mouse model(s)for their work.
文摘Parkinson's disease,the most common movement disorder,has a strong neuroinflammatory aspect.This is evident by increased pro-inflammatory cytokines in the serum,and the presence of activated microglial cells,and inflammatory cytokines in the substantia nigra of post-mortem brains as well as cerebrospinal fluid of Parkinson's disease patients.The central and peripheral neuroinflammatory aspects of Parkinson's disease can be investigated in vivo via administration of the inflammagen lipopolysaccharide,a component of the cell wall of gram-negative bacteria.In this mini-review,we will critically evaluate different routes of lipopolysaccharide administration(including intranasal systemic and ste reotasic),their relevance to clinical Parkinson's disease as well as the recent findings in lipopolysaccharide mouse models.We will also share our own expe riences with systemic and intrastriatal lipopolysaccharide models in C57BL/6 mice and will discuss the usefulness of lipopolysaccharide mouse models for future research in the field.
文摘Klinefelter syndrome(KS)is one of the most frequent genetic abnormalities and the leading genetic cause of nonobstructive azoospermia.The breeding and study of KS mouse models are essential to advancing our knowledge of the underlying pathological mechanism.Karyotyping and fluorescence in situ hybridization are reliable methods for identifying chromosomal contents.However,technical issues associated with these methods can decrease the efficiency of breeding KS mouse models and limit studies that require rapid identification of target mice.To overcome these limitations,we developed three polymerase chain reaction-based assays to measure specific genetic information,including presence or absence of the sex determining region of chromosome Y(Sry),copy number of amelogenin,X-linked(Amelx),and inactive X specific transcripts(Xist)levels.Through a combined analysis of the assay results,we can infer the karyotype of target mice.We confirmed the utility of our assays with the successful generation of KS mouse models.Our assays are rapid,inexpensive,high capacity,easy to perform,and only require small sample amounts.Therefore,they facilitate the breeding and study of KS mouse models and help advance our knowledge of the pathological mechanism underlying KS.
基金Supported by The Shanghai Municipal Natural Science Foundation,No.11ZR1405500the Shanghai Municipal Science and Technology Commission grant,No.13140902401
文摘AIM: To establish an orthotopic mouse model of pancreatic cancer that mimics the pathological features of exocrine pancreatic adenocarcinoma.
基金The National Natural Science Foundation of China,Grant/Award Number:82204006Science and Technology Project of Hebei Education Department,Grant/Award Number:QN2022009+1 种基金Medical Science Research Project of Hebei,Grant/Award Number:20221534National Natural Science Foundation of Hebei Province,Grant/Award Number:H2024209038。
文摘Background:It is well recognized that developing new animal models,refining the existing mouse models,and thoroughly characterizing their features are essential for gaining a deeper understanding of rosacea pathogenesis and for advancing therapeutic strategies in this direction.Accordingly,we aimed to characterize the pathological features of a long-term LL-37-induced mouse model of rosacea and to compare the disease manifestations and pathophysiological characteristics between short-term and long-term LL-37-induced models.A key focus was to investigate differential gene expression and the underlying mechanisms of immune system dysregulation in these models.Methods:We comparatively assessed skin lesion manifestations,the extent of inflammatory infiltration,sebaceous gland alterations,fibrosis,and angiogenesis in both models.Assessments were performed using photographic documentation,hematoxylin-eosin(HE)staining,Van Gieson's(VG)staining,immunohistochemistry,and Western blotting.Furthermore,we employed RNA sequencing to analyze differential gene expression in mouse skin.The RNA sequencing data were validated using immunofluorescence staining and Western blotting,with a specific focus on gene variations and mechanisms related to immune system dysregulation.Results:Mice subjected to long-term LL-37 induction developed rosacea-like pathological features,including angiogenesis,thickened skin tissue,and sebaceous gland hypertrophy.In the short-term LL-37-induced model,immune dysregulation primarily involved the innate immune response.However,long-term LL-37 induction resulted in significant activation of both innate and adaptive immune responses.Conclusion:The long-term LL-37-induced mouse model offers a valuable animal model for the detailed investigation of the pathological mechanisms driving moderate-to-severe rosacea with prolonged disease duration.Importantly,this model provides a significant experimental foundation for exploring the potential role of immune system dysregulation in rosacea pathogenesis.
文摘[ Objective] The aim of this study is to construct the model for simple obesity induced by high-fat diet, which is closest to human obesity, laying a foundation for the studies of obesity related theories. [Method[ ICR and KM mice, half male and half female, were randomly divided into the high-fat diet experimental group and the normal diet control group based on body weights, and certain days later, body weight, Lee＇ s index, wet weight of adipose tissue, quantity of adipose cell in the same visual field and blood indices were measured. [Result]All indices mentioned a- bove of the female I CR mouse had significant statistical differences with those of the control group （P 〈 0.01 or P 〈 0.05）. [ Conclusion] To con- struct mouse nutritional obesity model successfully, different high-fat diets are required by different lines as well as different sexes in the same line.
基金National Science and Technology Infrastructure of China,Grant/Award Number:National Pathogen Resource Center-NPRC-32National Key Research and Development Program of China,Grant/Award Number:2023YFF0724800CAMS Innovation Fund for Medical Sciences,Grant/Award Number:2021-I2M-1-035。
文摘Background:New variants of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continue to drive global epidemics and pose significant health risks.The pathogenicity of these variants evolves under immune pressure and host factors.Understanding these changes is crucial for epidemic control and variant research.Methods:Human angiotensin-converting enzyme 2(hACE2)transgenic mice were in-tranasally challenged with the original strain WH-09 and the variants Delta,Beta,and Omicron BA.1,while BALB/c mice were challenged with Omicron subvariants BA.5,BF.7,and XBB.1.To compare the pathogenicity differences among variants,we con-ducted a comprehensive analysis that included clinical symptom observation,meas-urement of viral loads in the trachea and lungs,evaluation of pulmonary pathology,analysis of immune cell infiltration,and quantification of cytokine levels.Results:In hACE2 mice,the Beta variant caused significant weight loss,severe lung inflammation,increased inflammatory and chemotactic factor secretion,greater mac-rophage and neutrophil infiltration in the lungs,and higher viral loads with prolonged shedding duration.In contrast,BA.1 showed a significant reduction in pathogenicity.The BA.5,BF.7,and XBB.1 variants were less pathogenic than the WH-09,Beta,and Delta variants when infected in BALB/c mice.This was evidenced by reduced weight loss,diminished pulmonary pathology,decreased secretion of inflammatory factors and chemokines,reduced macrophage and neutrophil infiltration,as well as lower viral loads in both the trachea and lungs.Conclusion:In hACE2 mice,the Omicron variant demonstrated the lowest pathogenic-ity,while the Beta variant exhibited the highest.Pathogenicity of the Delta variant was comparable to the original WH-09 strain.Among BALB/c mice,Omicron subvari-ants BA.5,BF.7,and XBB.1 showed no statistically significant differences in virulence.
