Dynamic tracking analysis of monoclonal antibodies(mAbs)biotransformation in vivo is crucial,as certain modifications could inactivate the protein and reduce drug efficacy.However,a particular challenge(i.e.immune rec...Dynamic tracking analysis of monoclonal antibodies(mAbs)biotransformation in vivo is crucial,as certain modifications could inactivate the protein and reduce drug efficacy.However,a particular challenge(i.e.immune recognition deficiencies)in biotransformation studies may arise when modifications occur at the paratope recognized by the antigen.To address this limitation,a multi-epitope affinity technology utilizing the metal organic framework(MOF)@Au@peptide@aptamer composite material was proposed and developed by simultaneously immobilizing complementarity determining region(CDR)mimotope peptide(HH24)and non-CDR mimotope aptamer(CH1S-6T)onto the surface of MOF@Au nanocomposite.Comparative studies demonstrated that MOF@Au@peptide@aptamer exhibited significantly enhanced enrichment capabilities for trastuzumab variants in comparison to mono-epitope affinity technology.Moreover,the higher deamidation ratio for LC-Asn-30 and isomerization ratio for HCAsn-55 can only be monitored by the novel bioanalytical platform based on MOF@Au@peptide@aptamer and liquid chromatography-quadrupole time of flight-mass spectrometry(LC-QTOF-MS).Therefore,multi-epitope affinity technology could effectively overcome the biases of traditional affinity materials for key sites modification analysis of mAb.Particularly,the novel bioanalytical platform can be successfully used for the tracking analysis of trastuzumab modifications in different biological fluids.Compared to the spiked phosphate buffer(PB)model,faster modification trends were monitored in the spiked serum and patients'sera due to the catalytic effect of plasma proteins and relevant proteases.Differences in peptide modification levels of trastuzumab in patients'sera were also monitored.In summary,the novel bioanalytical platform based on the multi-epitope affinity technology holds great potentials for in vivo biotransformation analysis of mAb,contributing to improved understanding and paving the way for future research and clinical applications.展开更多
In order to obtain induction expressed porcine circovirus type 2（PCV2）multi-epitope with good immunogenicity in vitro.Major epitopes of PCV2 were screened in the test,epitopes were composed sequentially,the c DNA se...In order to obtain induction expressed porcine circovirus type 2（PCV2）multi-epitope with good immunogenicity in vitro.Major epitopes of PCV2 were screened in the test,epitopes were composed sequentially,the c DNA sequences were artificially synthesized.Bam HⅠand SalⅠwere directionally cloned into prokaryotic expression vector PEGX-4T-1 multiple cloning site,then BL21 competent cells were transformed,positive clones were screened,IPTG inducible expression was conducted.Expression on target gene was analyzed by SDS-PAGE,fusion protein polypeptide was extracted and purified,immunocompetence of the expressed multi-epitope protein was identified by Westernblot.BALB/c mouse was immuned by fusion protein polypeptide,the antibody was determined by ELISA,immunogenicity was evaluated.Results showed that expression recombinant plasmid pEGX-4T-1-ep contained with seven PCV2 antigen epitopes had been constructed successfully.SDS-PAGE analysis showed that fusion protein polypeptide was expressed effectively in Escherichia coli（E.coli）,and the molecular weight was about 35ku,which existed in the form of solubility.Results of Westernblot showed that the extraction and purification of fusion protein polypeptide and PCV2 positive serum had good reactogenicity.Results of ELISA showed that the purified fusion protein polypeptide could stimulate the body to produce PCV2 specific antibody which had good immunogenicity.Results indicated that the constructed PCV2 multi-epitope had good expression characteristics in vitro,and the expression protein had good immunogenicity.The study provided a basic for the study on PCV2 epitope screening,functional identification and multi-epitope vaccine.展开更多
Hepatitis C (HCV) genome is highly variable, particularly in the hypervariable region 1 (HVR1) of its E2 envelope gene. The variability of HCV genome has been a major obstacle for developing HCV vaccines. Due to B-cel...Hepatitis C (HCV) genome is highly variable, particularly in the hypervariable region 1 (HVR1) of its E2 envelope gene. The variability of HCV genome has been a major obstacle for developing HCV vaccines. Due to B-cell HVR1 mimotopes mimicking the antigenicity of natural HVR1 epitopes; some T-cell epitopes from the consensus sequence of HCV genes conserving among the different HCV genotypes, we synthesized an minigene of HCV-derived multi-epitope peptide antigen (CMEP), which contains 9 B-cell HVR1 mimotopes in E2, 2 conserved CTL epitopes in C, 1 conserved CTL epitope in NS3; 1 conserved Th epitope in NS3. This minigene was cloned into a GST expression vector to generate a fusion protein GST-CMEP. The immunogenic properties of CEMP were characterized by HCV infected patients’ sera,; found that the reactivity frequency reached 75%. The cross reactivity of anti-CEMP antibody with different natural HVR1 variants was up to 90%. Meanwhile, we constructed an HCV DNA vaccine candidate, plasmid pVAX1.0-st-CMEP carrying the recombinant gene (st) of a secretion signal peptide; PADRE universal Th cell epitope sequence in front of the CMEP minigene. Immunization of rabbits with pVAX1.0-st-CMEP resulted in the production of antibody, which was of the same cross reactivity as the fusion protein GST-CMEP. Our findings indicate that the HCV-derived multi-epitope peptide antigen in some degree possessed the characteristics of neutralizing HCV epitopes,; would be of the value as a candidate for the development of HCV vaccines.展开更多
Peptostreptococcus anaerobius is an anaerobic bacterium,which has been found selectively en-riched in the fecal and mucosal microbiota of colorectal cancer(CRC)patients.Emerging evidence suggest P.anaerobius may contr...Peptostreptococcus anaerobius is an anaerobic bacterium,which has been found selectively en-riched in the fecal and mucosal microbiota of colorectal cancer(CRC)patients.Emerging evidence suggest P.anaerobius may contribute to the development of CRC in human.In this study,we designed a multi-epitope chimeric vaccine against P.anaerobius PCWBR2,a recently identified adhesin that interacts directly with colon cell lines by bindingα2/β1 integrin frequently overexpressed in human CRC tumors and cell lines.Immunoinformatics tools predicted six cytotoxic T lymphocyte epitopes,five helper T lymphocyte epitopes,and six linear B lymphocyte epitopes.The predicted epitopes were joined with AAY or GPGPG linkers and a previously reported TLR4 agonist was added to the vaccine construct’s N terminal as an adjuvant using EAAAK linkers and the order of epitopes was optimized.Further in silico analysis revealed that the vaccine construct possesses satisfactory antigenicity,allergenicity,solubility,physicochemical properties,adjuvant-TLR4 molecular docking,and immune profile characteristics.Our study provided a promising design for vaccines against P.anaerobius.展开更多
Background:Following the decline of malaria transmission in many countries and regions,serological parameters have become particularly useful for estimating malaria transmission in low-intensity areas.This study evalu...Background:Following the decline of malaria transmission in many countries and regions,serological parameters have become particularly useful for estimating malaria transmission in low-intensity areas.This study evaluated a novel serological marker,Malaria Random Constructed Antigen-1(M.RCAg-1),which contains 11 epitopes from eight Plasmodium falciparum antigens,as a tool for assessing malaria transmission intensity along the border area of China-Myanmar.Method:Serum from Plasmodium falciparum and P.vivax patients was used to detect the properties of M.RCAg-1 and antibody responses.Cross-sectional surveys were conducted at the China-Myanmar border and in Hainan province in 2012 and 2013 using cluster sampling.Filter blood spot papers were collected from all participants.Antibodies against M.RCAg-1 were detected using indirect ELISA.The Mann–Whitney test and Spearman’s rank correlation test were performed to analyze antibody data.P.falciparum malaria transmission intensity was estimated using a catalytic conversion model based on the maximum likelihood of generating a community seroconversion rate(SCR).Results:M.RCAg-1 was well-recognized by the naturally acquired anti-malaria antibodies in P.falciparum patients and had very limited cross-reactivity with P.vivax infection.The total amount of IgG antibodies was decreased with the decrease in parasitemia after taking medication and lasted several weeks.In a population survey,the antibody levels were higher in residents living close to the China-Myanmar border than those living in non-epidemic areas(P<0.0001),but no significant difference was observed between residents from Hainan and non-epidemic areas.The calculated SCR was 0.0128 for Jieyangka,0.004 for Susuzhai,0.0047 for Qiushan,and 0.043 for Kayahe.The estimated exposure rate obtained from the anti-M.RCAg-1 antibody level correlated with traditional measures of transmission intensity derived from altitude.Conclusion:Our study demonstrates that M.RCAg-1 is potentially useful as a serological indicator of exposure to P.falciparum malaria,especially for malaria surveillance in low transmission areas.展开更多
The epidemic of HIV/AIDS is sweeping across the world. It is of great importance to figure out new ways to curb this disease. Epitope-based vaccine is one of these solutions. In this study, a chimeric gene was obtaine...The epidemic of HIV/AIDS is sweeping across the world. It is of great importance to figure out new ways to curb this disease. Epitope-based vaccine is one of these solutions. In this study, a chimeric gene was obtained by combination of a designed HIV-1 multi-epitope gene (MEG) and HIV-1 p24 gene. A re- combinant plasmid pUTA2-MEGp24 was then constructed by inserting MEGp24 gene into the down- stream of the promoter (ATI-P7.5×20) of fowlpox virus (FPV) transfer vector pUTA2. The recombinant plasmid and wild-type FPV 282E4 strain were then co-transfected into CEF cells and homologous re- combination occurred. A recombinant virus expressing HIV-1 protein MEGp24 was screened by ge- nome PCR and Western blot assay. Large scale preparation and purification of the recombinant fowl- pox virus (rFPV) were then carried out. BALB/c mice were immunized intramuscularly with the rFPV for three times on day 0, 14 and 42. Mice were executed and sampled one week after the third inoculation. Anti-HIV-1 antibody in serum and Th1 cytokines in the supernatant of cultured spleen cells were as- sayed by ELISA. The count of T lymphocyte subsets and the CTL activity of spleen lymphocytes were analyzed by flow cytometry and lactate dehydrogenase (LDH) release assay, respectively. The results showed that HIV-1 specific antibody in serum and increased T lymphocyte subsets (CD4+ T, CD8+ T) were detected in the immunization group. CTL target-killing activity and higher secretion of Th1 cyto- kines (IFN-γ and IL-2) of spleen lymphocytes stimulated by H-2d-restricted CTL peptide were observed in immunized mice. We concluded that the rFPV may induce HIV-1 specific immunity especially cellular immunity in mice.展开更多
Five highly conserved and immunogenic epitopes of hepatitis C virus (HCV) have been chosen to form a multi-epitope antigen gene and fused with β-galactosidase gene to express a hybrid GZ-PCX antigen, which could be s...Five highly conserved and immunogenic epitopes of hepatitis C virus (HCV) have been chosen to form a multi-epitope antigen gene and fused with β-galactosidase gene to express a hybrid GZ-PCX antigen, which could be specifically recognized by human HCV sera. High level of anti-GZ-PCX IgG has been induced when mice or rabbits were immunized with GZ-PCX antigen emulsificated with complete Freund’s adjuvant or mixed with killed attenuated Salmonella typhimurium SL3261. The specific anti-GZ-PCX IgG reached a high liter of 10-6, which remained for several months. Specific cytotoxic T lymphocyte (CTL) effects, delayed type hypersensltivity reaction (DTH) and proliferation of peripheral lymphocytes have been induced by GZ-PCX antigen or synthetic peptides. High level of anti-GZ-PCX slgG has been detected in mice’s intestinal washing fluids, which indicates that the antigen induced mucosal immunity as well as systematic immunity. The studies show that the HCV multi-epitope antigen induces high level of specific immune responses without obvious toxicity, which might be able to provide protectivity to any HCV genotypes and isolates.展开更多
Background:Tuberculosis(TB)remains a global public health challenge.The existing Bacillus Calmette–Guérin vaccine has limited efficacy in preventing adult pulmonary TB,necessitating the development of new vaccin...Background:Tuberculosis(TB)remains a global public health challenge.The existing Bacillus Calmette–Guérin vaccine has limited efficacy in preventing adult pulmonary TB,necessitating the development of new vaccines with improved protective effects.Methods:Computer-aided design and artificial intelligence technologies,combined with bioinformatics and im-munoinformatics approaches,were used to design a multi-epitope vaccine(MEV)against TB.Comprehensive bioinformatics analyses were conducted to evaluate the physicochemical properties,spatial structure,immuno-genicity,molecular dynamics(MD),and immunological characteristics of the MEV.Results:We constructed a MEV,designated ZL12138L,containing 13 helper T lymphocyte epitopes,12 cyto-toxic T lymphocyte epitopes,8 B-cell epitopes,as well as Toll-like receptor(TLR)agonists and helper peptides.Bioinformatics analyses revealed that ZL12138L should exhibit excellent immunogenicity and antigenicity,with no toxicity or allergenicity,and had potential to induce robust immune responses and high solubility,the im-munogenicity score was 4.14449,the antigenicity score was 0.8843,and the immunological score was 0.470.Moreover,ZL12138L showed high population coverage for human leukocyte antigen class I and II alleles,reach-ing 92.41%and 90.17%,respectively,globally.Molecular docking analysis indicated favorable binding affinity of ZL12138L with TLR-2 and TLR-4,with binding energies of−1173.4 and−1360.5 kcal/mol,respectively.Nor-mal mode analysis and MD simulations indicated the stability and dynamic properties of the vaccine construct.Immune simulation predictions suggested that ZL12138L could effectively activate innate and adaptive immune cells,inducing high levels of Type 1 T helper cell cytokines.Conclusions:This study provides compelling evidence for ZL12138L as a promising TB vaccine candidate.Future research will focus on experimental validation and further optimization of the vaccine design.展开更多
The emergence of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants capable of evading both convalescent and vaccine-triggered antibody responses has underscored the pivotal role of T-cell immunity in...The emergence of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants capable of evading both convalescent and vaccine-triggered antibody responses has underscored the pivotal role of T-cell immunity in antiviral defense.Here,we develop the ConFormer network for epitope prediction,which couples convolutional neural network(CNN)local features with Transformer global representations to enhance binding prediction performance,and employ the deep learning algorithm and bioinformatics workflows to identify conserved T-cell epitopes within the SARS-CoV-2 proteome.Five epitopes are identified as potential inducers of T-cell immune responses.Notably,the multi-valent vaccine composed of these five peptides significantly activates cluster of differentiation(CD)8^(+)and CD4^(+)T cells both in vitro and in vivo.The serum of mice immunized with this vaccine is able to neutralize the five major SARS-CoV-2 variants of concern.This study provides a candidate peptide vaccine with the potential to trigger antiviral T-cell responses,thereby offering the prospect of immune protection against SARS-CoV-2 variants.展开更多
The aim of the research is to increase the applicability of lipopeptides as drugs.To this end,non-ionic triblock copolymers,namely poloxamers,were applied.The physico-chemical properties of poloxamers vary depending o...The aim of the research is to increase the applicability of lipopeptides as drugs.To this end,non-ionic triblock copolymers,namely poloxamers,were applied.The physico-chemical properties of poloxamers vary depending on the length of the blocks.In our study,we experimented with different types and systematically investigated the variation of the critical micelle concentration(CMC)of poloxamers at 25 and 37°C in different media.In addition,the cytotoxicity of the different poloxamer micelles on three different cell lines was evaluated,and based on the results,Plur104,Plur123,and Plur127 were selected.Fatty acid elongated derivatives of a short antibacterial peptide(pL1),a medium-sized anticancer peptide(pCM15),and a branched-chain vaccine antigen(pATIPC)were used as lipopeptide models,and their formulations with the selected poloxamers were investigated.The solubility and homogeneity of the lipopeptides were significantly increased,and dynamic light scattering(DLS)measurements showed the formation of small particles of around 20 nm,which were well reproducible and storable.Similar homogenous micelle formation was observed after freeze-drying and reconstitution with water.The pL1 lipopeptide,formulated with the selected poloxamers,exhibited enhanced antibacterial activity with significantly reduced haemolytic side effects.The pCM15 peptide,when incorporated into poloxamer micelles,showed significantly enhanced cytotoxicity against tumor cells.Additionally,the internalization rate of poloxamer-formulated pATIPC peptide by antigen-presenting model cells exceeded that of the unformulated peptide.Our results demonstrate the potential of poloxamers as promising tools for the formulation of lipopeptides and for the optimization of their selectivity.展开更多
Currently,the incorporation of multiple epitopes into vaccines is more desirable than the incorporation of a single antigen for universal influenza vaccine development.However,epitopes induce poor immune responses.Alt...Currently,the incorporation of multiple epitopes into vaccines is more desirable than the incorporation of a single antigen for universal influenza vaccine development.However,epitopes induce poor immune responses.Although the use of adjuvants can overcome this obstacle,it may raise new problems.Effective antigen delivery vehicles that can function as both antigen carriers and intrinsic adjuvants are highly desired for vaccine development.Here,we report a biepitope nanovaccine that provides complete protection in mice against H3N2 virus as well as partial protection against H1N1 virus.This vaccine(3MCD-f)consists of two conserved epitopes(matrix protein 2 ectodomain(M2e)and CDhelix),and these epitopes were presented on the surface of ferritin in a sequential tandem format.Subcutaneous immunization with 3MCD-f in the absence of adjuvant induces robust humoral and cellular immune responses.These results provide a proof of concept for the 3MCD-f nanovaccine that might be an ideal candidate for future influenza pandemics.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.:82373829,82273893,and 82173773)the Natural Science Foundation of Guangdong Province,China(Grant Nos.:2021A1515220099,and 2022A1515011576)+1 种基金the High-End Foreign Experts Project,China(Grant No.:G2021199005L)the Science and Technology Program of Guangdong Provincial Medical Products Administration,China(Grant Nos.:2023TDZ11,and 2022ZDB04).
文摘Dynamic tracking analysis of monoclonal antibodies(mAbs)biotransformation in vivo is crucial,as certain modifications could inactivate the protein and reduce drug efficacy.However,a particular challenge(i.e.immune recognition deficiencies)in biotransformation studies may arise when modifications occur at the paratope recognized by the antigen.To address this limitation,a multi-epitope affinity technology utilizing the metal organic framework(MOF)@Au@peptide@aptamer composite material was proposed and developed by simultaneously immobilizing complementarity determining region(CDR)mimotope peptide(HH24)and non-CDR mimotope aptamer(CH1S-6T)onto the surface of MOF@Au nanocomposite.Comparative studies demonstrated that MOF@Au@peptide@aptamer exhibited significantly enhanced enrichment capabilities for trastuzumab variants in comparison to mono-epitope affinity technology.Moreover,the higher deamidation ratio for LC-Asn-30 and isomerization ratio for HCAsn-55 can only be monitored by the novel bioanalytical platform based on MOF@Au@peptide@aptamer and liquid chromatography-quadrupole time of flight-mass spectrometry(LC-QTOF-MS).Therefore,multi-epitope affinity technology could effectively overcome the biases of traditional affinity materials for key sites modification analysis of mAb.Particularly,the novel bioanalytical platform can be successfully used for the tracking analysis of trastuzumab modifications in different biological fluids.Compared to the spiked phosphate buffer(PB)model,faster modification trends were monitored in the spiked serum and patients'sera due to the catalytic effect of plasma proteins and relevant proteases.Differences in peptide modification levels of trastuzumab in patients'sera were also monitored.In summary,the novel bioanalytical platform based on the multi-epitope affinity technology holds great potentials for in vivo biotransformation analysis of mAb,contributing to improved understanding and paving the way for future research and clinical applications.
基金Supported by Shandong Province Natural Science Foundation of China(ZR2013CQ006)
文摘In order to obtain induction expressed porcine circovirus type 2（PCV2）multi-epitope with good immunogenicity in vitro.Major epitopes of PCV2 were screened in the test,epitopes were composed sequentially,the c DNA sequences were artificially synthesized.Bam HⅠand SalⅠwere directionally cloned into prokaryotic expression vector PEGX-4T-1 multiple cloning site,then BL21 competent cells were transformed,positive clones were screened,IPTG inducible expression was conducted.Expression on target gene was analyzed by SDS-PAGE,fusion protein polypeptide was extracted and purified,immunocompetence of the expressed multi-epitope protein was identified by Westernblot.BALB/c mouse was immuned by fusion protein polypeptide,the antibody was determined by ELISA,immunogenicity was evaluated.Results showed that expression recombinant plasmid pEGX-4T-1-ep contained with seven PCV2 antigen epitopes had been constructed successfully.SDS-PAGE analysis showed that fusion protein polypeptide was expressed effectively in Escherichia coli（E.coli）,and the molecular weight was about 35ku,which existed in the form of solubility.Results of Westernblot showed that the extraction and purification of fusion protein polypeptide and PCV2 positive serum had good reactogenicity.Results of ELISA showed that the purified fusion protein polypeptide could stimulate the body to produce PCV2 specific antibody which had good immunogenicity.Results indicated that the constructed PCV2 multi-epitope had good expression characteristics in vitro,and the expression protein had good immunogenicity.The study provided a basic for the study on PCV2 epitope screening,functional identification and multi-epitope vaccine.
基金supported by the National Natural Science Foundation of China(Grant No.30471596)
文摘Hepatitis C (HCV) genome is highly variable, particularly in the hypervariable region 1 (HVR1) of its E2 envelope gene. The variability of HCV genome has been a major obstacle for developing HCV vaccines. Due to B-cell HVR1 mimotopes mimicking the antigenicity of natural HVR1 epitopes; some T-cell epitopes from the consensus sequence of HCV genes conserving among the different HCV genotypes, we synthesized an minigene of HCV-derived multi-epitope peptide antigen (CMEP), which contains 9 B-cell HVR1 mimotopes in E2, 2 conserved CTL epitopes in C, 1 conserved CTL epitope in NS3; 1 conserved Th epitope in NS3. This minigene was cloned into a GST expression vector to generate a fusion protein GST-CMEP. The immunogenic properties of CEMP were characterized by HCV infected patients’ sera,; found that the reactivity frequency reached 75%. The cross reactivity of anti-CEMP antibody with different natural HVR1 variants was up to 90%. Meanwhile, we constructed an HCV DNA vaccine candidate, plasmid pVAX1.0-st-CMEP carrying the recombinant gene (st) of a secretion signal peptide; PADRE universal Th cell epitope sequence in front of the CMEP minigene. Immunization of rabbits with pVAX1.0-st-CMEP resulted in the production of antibody, which was of the same cross reactivity as the fusion protein GST-CMEP. Our findings indicate that the HCV-derived multi-epitope peptide antigen in some degree possessed the characteristics of neutralizing HCV epitopes,; would be of the value as a candidate for the development of HCV vaccines.
基金supported by the National Key Research and Development Program of China(Grant No.2020YFA0907800)the National Natural Science Foundation of China(Grant No.32000096)+2 种基金the Shenzhen Science and Technology Innovation Program(KQTD20200820145822023)the Program of Shenzhen Key Laboratory of Systems Medicine for Inflammatory Diseases(ZDSYS20220606100803007)the Foshan Science and Technology Innovation Program(2120001010795).
文摘Peptostreptococcus anaerobius is an anaerobic bacterium,which has been found selectively en-riched in the fecal and mucosal microbiota of colorectal cancer(CRC)patients.Emerging evidence suggest P.anaerobius may contribute to the development of CRC in human.In this study,we designed a multi-epitope chimeric vaccine against P.anaerobius PCWBR2,a recently identified adhesin that interacts directly with colon cell lines by bindingα2/β1 integrin frequently overexpressed in human CRC tumors and cell lines.Immunoinformatics tools predicted six cytotoxic T lymphocyte epitopes,five helper T lymphocyte epitopes,and six linear B lymphocyte epitopes.The predicted epitopes were joined with AAY or GPGPG linkers and a previously reported TLR4 agonist was added to the vaccine construct’s N terminal as an adjuvant using EAAAK linkers and the order of epitopes was optimized.Further in silico analysis revealed that the vaccine construct possesses satisfactory antigenicity,allergenicity,solubility,physicochemical properties,adjuvant-TLR4 molecular docking,and immune profile characteristics.Our study provided a promising design for vaccines against P.anaerobius.
基金supported in full by the National Special Science and Technology Project for Major Infectious Diseases of China(No.2012ZX10004220).
文摘Background:Following the decline of malaria transmission in many countries and regions,serological parameters have become particularly useful for estimating malaria transmission in low-intensity areas.This study evaluated a novel serological marker,Malaria Random Constructed Antigen-1(M.RCAg-1),which contains 11 epitopes from eight Plasmodium falciparum antigens,as a tool for assessing malaria transmission intensity along the border area of China-Myanmar.Method:Serum from Plasmodium falciparum and P.vivax patients was used to detect the properties of M.RCAg-1 and antibody responses.Cross-sectional surveys were conducted at the China-Myanmar border and in Hainan province in 2012 and 2013 using cluster sampling.Filter blood spot papers were collected from all participants.Antibodies against M.RCAg-1 were detected using indirect ELISA.The Mann–Whitney test and Spearman’s rank correlation test were performed to analyze antibody data.P.falciparum malaria transmission intensity was estimated using a catalytic conversion model based on the maximum likelihood of generating a community seroconversion rate(SCR).Results:M.RCAg-1 was well-recognized by the naturally acquired anti-malaria antibodies in P.falciparum patients and had very limited cross-reactivity with P.vivax infection.The total amount of IgG antibodies was decreased with the decrease in parasitemia after taking medication and lasted several weeks.In a population survey,the antibody levels were higher in residents living close to the China-Myanmar border than those living in non-epidemic areas(P<0.0001),but no significant difference was observed between residents from Hainan and non-epidemic areas.The calculated SCR was 0.0128 for Jieyangka,0.004 for Susuzhai,0.0047 for Qiushan,and 0.043 for Kayahe.The estimated exposure rate obtained from the anti-M.RCAg-1 antibody level correlated with traditional measures of transmission intensity derived from altitude.Conclusion:Our study demonstrates that M.RCAg-1 is potentially useful as a serological indicator of exposure to P.falciparum malaria,especially for malaria surveillance in low transmission areas.
文摘The epidemic of HIV/AIDS is sweeping across the world. It is of great importance to figure out new ways to curb this disease. Epitope-based vaccine is one of these solutions. In this study, a chimeric gene was obtained by combination of a designed HIV-1 multi-epitope gene (MEG) and HIV-1 p24 gene. A re- combinant plasmid pUTA2-MEGp24 was then constructed by inserting MEGp24 gene into the down- stream of the promoter (ATI-P7.5×20) of fowlpox virus (FPV) transfer vector pUTA2. The recombinant plasmid and wild-type FPV 282E4 strain were then co-transfected into CEF cells and homologous re- combination occurred. A recombinant virus expressing HIV-1 protein MEGp24 was screened by ge- nome PCR and Western blot assay. Large scale preparation and purification of the recombinant fowl- pox virus (rFPV) were then carried out. BALB/c mice were immunized intramuscularly with the rFPV for three times on day 0, 14 and 42. Mice were executed and sampled one week after the third inoculation. Anti-HIV-1 antibody in serum and Th1 cytokines in the supernatant of cultured spleen cells were as- sayed by ELISA. The count of T lymphocyte subsets and the CTL activity of spleen lymphocytes were analyzed by flow cytometry and lactate dehydrogenase (LDH) release assay, respectively. The results showed that HIV-1 specific antibody in serum and increased T lymphocyte subsets (CD4+ T, CD8+ T) were detected in the immunization group. CTL target-killing activity and higher secretion of Th1 cyto- kines (IFN-γ and IL-2) of spleen lymphocytes stimulated by H-2d-restricted CTL peptide were observed in immunized mice. We concluded that the rFPV may induce HIV-1 specific immunity especially cellular immunity in mice.
文摘Five highly conserved and immunogenic epitopes of hepatitis C virus (HCV) have been chosen to form a multi-epitope antigen gene and fused with β-galactosidase gene to express a hybrid GZ-PCX antigen, which could be specifically recognized by human HCV sera. High level of anti-GZ-PCX IgG has been induced when mice or rabbits were immunized with GZ-PCX antigen emulsificated with complete Freund’s adjuvant or mixed with killed attenuated Salmonella typhimurium SL3261. The specific anti-GZ-PCX IgG reached a high liter of 10-6, which remained for several months. Specific cytotoxic T lymphocyte (CTL) effects, delayed type hypersensltivity reaction (DTH) and proliferation of peripheral lymphocytes have been induced by GZ-PCX antigen or synthetic peptides. High level of anti-GZ-PCX slgG has been detected in mice’s intestinal washing fluids, which indicates that the antigen induced mucosal immunity as well as systematic immunity. The studies show that the HCV multi-epitope antigen induces high level of specific immune responses without obvious toxicity, which might be able to provide protectivity to any HCV genotypes and isolates.
基金sponsored by the Beijing Nova Program(20240484526).
文摘Background:Tuberculosis(TB)remains a global public health challenge.The existing Bacillus Calmette–Guérin vaccine has limited efficacy in preventing adult pulmonary TB,necessitating the development of new vaccines with improved protective effects.Methods:Computer-aided design and artificial intelligence technologies,combined with bioinformatics and im-munoinformatics approaches,were used to design a multi-epitope vaccine(MEV)against TB.Comprehensive bioinformatics analyses were conducted to evaluate the physicochemical properties,spatial structure,immuno-genicity,molecular dynamics(MD),and immunological characteristics of the MEV.Results:We constructed a MEV,designated ZL12138L,containing 13 helper T lymphocyte epitopes,12 cyto-toxic T lymphocyte epitopes,8 B-cell epitopes,as well as Toll-like receptor(TLR)agonists and helper peptides.Bioinformatics analyses revealed that ZL12138L should exhibit excellent immunogenicity and antigenicity,with no toxicity or allergenicity,and had potential to induce robust immune responses and high solubility,the im-munogenicity score was 4.14449,the antigenicity score was 0.8843,and the immunological score was 0.470.Moreover,ZL12138L showed high population coverage for human leukocyte antigen class I and II alleles,reach-ing 92.41%and 90.17%,respectively,globally.Molecular docking analysis indicated favorable binding affinity of ZL12138L with TLR-2 and TLR-4,with binding energies of−1173.4 and−1360.5 kcal/mol,respectively.Nor-mal mode analysis and MD simulations indicated the stability and dynamic properties of the vaccine construct.Immune simulation predictions suggested that ZL12138L could effectively activate innate and adaptive immune cells,inducing high levels of Type 1 T helper cell cytokines.Conclusions:This study provides compelling evidence for ZL12138L as a promising TB vaccine candidate.Future research will focus on experimental validation and further optimization of the vaccine design.
基金supported in part by the National Natural Science Foundation of China(82150208 and 82425104)the National Key Research and Development Program of China(2022YFC3400501)the Shanghai Rising-Star Program(23QA1402800).
文摘The emergence of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants capable of evading both convalescent and vaccine-triggered antibody responses has underscored the pivotal role of T-cell immunity in antiviral defense.Here,we develop the ConFormer network for epitope prediction,which couples convolutional neural network(CNN)local features with Transformer global representations to enhance binding prediction performance,and employ the deep learning algorithm and bioinformatics workflows to identify conserved T-cell epitopes within the SARS-CoV-2 proteome.Five epitopes are identified as potential inducers of T-cell immune responses.Notably,the multi-valent vaccine composed of these five peptides significantly activates cluster of differentiation(CD)8^(+)and CD4^(+)T cells both in vitro and in vivo.The serum of mice immunized with this vaccine is able to neutralize the five major SARS-CoV-2 variants of concern.This study provides a candidate peptide vaccine with the potential to trigger antiviral T-cell responses,thereby offering the prospect of immune protection against SARS-CoV-2 variants.
基金support of the Lendület(Momentum)Programme of the Hungarian Academy of Sciences(Grant No.:LP2021-28)the National Research,Development and Innovation Fund of Hungary,financed under the 2018-1.2.1-NKP funding scheme(Project No.:2018-1.2.1-NKP-2018-00005)the National Research,Development and Innovation Office,NKFIH,Hungary(Grant Nos.:K131594,2020-1-1-2-PIACI-KFI_2020-00021,and TKP2021-EGA-31).
文摘The aim of the research is to increase the applicability of lipopeptides as drugs.To this end,non-ionic triblock copolymers,namely poloxamers,were applied.The physico-chemical properties of poloxamers vary depending on the length of the blocks.In our study,we experimented with different types and systematically investigated the variation of the critical micelle concentration(CMC)of poloxamers at 25 and 37°C in different media.In addition,the cytotoxicity of the different poloxamer micelles on three different cell lines was evaluated,and based on the results,Plur104,Plur123,and Plur127 were selected.Fatty acid elongated derivatives of a short antibacterial peptide(pL1),a medium-sized anticancer peptide(pCM15),and a branched-chain vaccine antigen(pATIPC)were used as lipopeptide models,and their formulations with the selected poloxamers were investigated.The solubility and homogeneity of the lipopeptides were significantly increased,and dynamic light scattering(DLS)measurements showed the formation of small particles of around 20 nm,which were well reproducible and storable.Similar homogenous micelle formation was observed after freeze-drying and reconstitution with water.The pL1 lipopeptide,formulated with the selected poloxamers,exhibited enhanced antibacterial activity with significantly reduced haemolytic side effects.The pCM15 peptide,when incorporated into poloxamer micelles,showed significantly enhanced cytotoxicity against tumor cells.Additionally,the internalization rate of poloxamer-formulated pATIPC peptide by antigen-presenting model cells exceeded that of the unformulated peptide.Our results demonstrate the potential of poloxamers as promising tools for the formulation of lipopeptides and for the optimization of their selectivity.
基金the National Natural Science Foundation of China(No.31770996).
文摘Currently,the incorporation of multiple epitopes into vaccines is more desirable than the incorporation of a single antigen for universal influenza vaccine development.However,epitopes induce poor immune responses.Although the use of adjuvants can overcome this obstacle,it may raise new problems.Effective antigen delivery vehicles that can function as both antigen carriers and intrinsic adjuvants are highly desired for vaccine development.Here,we report a biepitope nanovaccine that provides complete protection in mice against H3N2 virus as well as partial protection against H1N1 virus.This vaccine(3MCD-f)consists of two conserved epitopes(matrix protein 2 ectodomain(M2e)and CDhelix),and these epitopes were presented on the surface of ferritin in a sequential tandem format.Subcutaneous immunization with 3MCD-f in the absence of adjuvant induces robust humoral and cellular immune responses.These results provide a proof of concept for the 3MCD-f nanovaccine that might be an ideal candidate for future influenza pandemics.
