Objective:To assess aptamer-based assays for diagnosing latent tuberculosis infection(LTBI).Methods:Literature from Medline,ScienceDirect,and Scopus,covering publications from January 1,2012,to December 31,2023,was ex...Objective:To assess aptamer-based assays for diagnosing latent tuberculosis infection(LTBI).Methods:Literature from Medline,ScienceDirect,and Scopus,covering publications from January 1,2012,to December 31,2023,was examined.This review evaluates different aptamers,biomarkers,sample types,sample sizes,reference assays,and the assays'sensitivity and specificity.By using the Quality Assessment of Diagnostic Accuracy Studies 2,the risk of bias in each study was evaluated.Results:Aptamer-based assays generally showed a sensitivity of 90%(95%CI:75%-100%)and specificity of 90%(95%CI:50%-100%),where optical aptasensor showed the highest sensitivity and specificity at 100%.Serum samples were frequently used to enhance antigen detectability,improving the assay’s performance.Meanwhile,HspX was the most studied biomarker,followed by MPT64,and IFN-γ.Conclusions:Aptamer-based assays could be reliable alternatives to current LTBI detection methods,but further research is needed to validate their clinical efficacy.展开更多
Diabetes and insulinoma represent opposing alterations in pancreatic β-cell mass,with diabetes resulting from irreversible β-cells damage and insulinoma arising from abnormal proliferation.Early diagnosis of both co...Diabetes and insulinoma represent opposing alterations in pancreatic β-cell mass,with diabetes resulting from irreversible β-cells damage and insulinoma arising from abnormal proliferation.Early diagnosis of both conditions necessitates effectiveβ-cell mass detection.Current detection methods are limited in diagnosing each condition individually or lacking timely and accurate detection.Diabetes is typically identified only after significantβ-cell loss,while insulinoma can evade conventional imaging due to their small size.Positron emission tomography/computed tomography(PET/CT)imaging,combining anatomical and functional data,enhances diagnostic accuracy but faces challenges in specificity.This study employed two RNA aptamers(m12–3773 and 1–717)modified to enhance RNase resistance and conjugated with68Ga to create ^(68)Ga-NOTA-Ap.^(68)Ga-NOTA-Ap was administered to rats with pancreaticβ-cell damage and mice with insulinoma to evaluate its ability to image islets,detect changes in pancreatic β-cell mass(BCM),and identify insulinoma.Modified with methoxy and fluoro,RNA aptamers exhibited enhanced stability and RNases resistance while retaining their dissociation constants(K_(d)).Furthermore,^(68)Ga-NOTA-Ap effectively detected changes of BCM in rats with pancreatic β-cell damage and imaged insulinoma in mice through recognition of abnormalβ-cell proliferation by recognizing clusterin and transmembrane p24 trafficking protein 6(TMED6)on pancreaticβ-cell.The developed ^(68)Ga-NOTA-Ap shows promise for early screening of diabetes and insulinoma due to its high sensitivity,specificity,and non-invasive nature.It has potential clinical applications for monitoring pancreatic β-cell function and diagnosing insulinoma.展开更多
Heterodimerization in RTKs is of vital importance in the RTK signaling and cell functions.Heterodimerization between RTKs can result in diversity of downstream signals,increasing the ability of cells to respond to ext...Heterodimerization in RTKs is of vital importance in the RTK signaling and cell functions.Heterodimerization between RTKs can result in diversity of downstream signals,increasing the ability of cells to respond to external experiments.Traditional RTKs heterodimerization always occur in the same families and is lack of agonists to activate the heterodimeric RTKs signaling pathway.Herein,we developed the DNA agonist based on bivalent aptamers for the heterodimerized RTKs of different families,AF/AM-1,which could simultaneously activate FGFR1 and c-Met signaling.It is the first agonist that realizing the heterodimerization and activation of FGFR1 and c-Met,two different RTK families.The activation of FGFR1/c-Met heterodimer result in the down-stream signals transduction,such as the phosphorylation of Akt and Erk,inducing the cell migration and proliferation.The DNA agonist for RTK heterodimer of different families would have potential applications in the fields of biomedicine.展开更多
Precision medicine has become a cornerstone in modern therapeutic strategies, with nucleic acid aptamers emerging aspivotal tools due to their unique properties. These oligonucleotide fragments, selected through the S...Precision medicine has become a cornerstone in modern therapeutic strategies, with nucleic acid aptamers emerging aspivotal tools due to their unique properties. These oligonucleotide fragments, selected through the Systematic Evolution ofLigands by Exponential Enrichment process, exhibit high affinity and specificity toward their targets, such as DNA, RNA,proteins, and other biomolecules. Nucleic acid aptamers offer significant advantages over traditional therapeutic agents,including superior biological stability, minimal immunogenicity, and the capacity for universal chemical modifications thatenhance their in vivo performance and targeting precision. In the realm of osseous tissue repair and regeneration, a complexphysiological process essential for maintaining skeletal integrity, aptamers have shown remarkable potential in influencingmolecular pathways crucial for bone regeneration, promoting osteogenic differentiation and supporting osteoblast survival. Byengineering aptamers to regulate inflammatory responses and facilitate the proliferation and differentiation of fibroblasts,these oligonucleotides can be integrated into advanced drug delivery systems, significantly improving bone repair efficacywhile minimizing adverse effects. Aptamer-mediated strategies, including the use of siRNA and miRNA mimics or inhibitors,have shown efficacy in enhancing bone mass and microstructure. These approaches hold transformative potential for treatinga range of orthopedic conditions like osteoporosis, osteosarcoma, and osteoarthritis. This review synthesizes the molecularmechanisms and biological roles of aptamers in orthopedic diseases, emphasizing their potential to drive innovative andeffective therapeutic interventions.展开更多
Aptamers are a type of single-chain oligonucleotide that can combine with a specific target.Due to their simple preparation,easy modification,stable structure and reusability,aptamers have been widely applied as bioch...Aptamers are a type of single-chain oligonucleotide that can combine with a specific target.Due to their simple preparation,easy modification,stable structure and reusability,aptamers have been widely applied as biochemical sensors for medicine,food safety and environmental monitoring.However,there is little research on aptamer-target binding mechanisms,which limits their application and development.Computational simulation has gained much attention for revealing aptamer-target binding mechanisms at the atomic level.This work summarizes the main simulation methods used in the mechanistic analysis of aptamer-target complexes,the characteristics of binding between aptamers and different targets(metal ions,small organic molecules,biomacromolecules,cells,bacteria and viruses),the types of aptamer-target interactions and the factors influencing their strength.It provides a reference for further use of simulations in understanding aptamer-target binding mechanisms.展开更多
Exosomes(EXOs)have showed great potential in regenerative medicine.The separation of EXOs from complex biological media is essential for the down-stream applications.Herein,we report a deoxyribonucleic acid(DNA)-based...Exosomes(EXOs)have showed great potential in regenerative medicine.The separation of EXOs from complex biological media is essential for the down-stream applications.Herein,we report a deoxyribonucleic acid(DNA)-based micro-complex(DMC)containing polyaptamers,which realized the specific separation of EXOs from cell culture media and the significant promotion of wound healing.The synthesis of DMCs was based on a biomineralization process via rolling circle amplification(RCA)under the catalysis of phi29 DNA polymerase.To endow DMCs with the ability to capture EXOs,the DNA template of RCA was integrated with complementary sequence of aptamer that specifically recognized the CD63 proteins on EXOs.The obtained DMCs contained polyaptamers that can specifically capture the EXOs in cell culture media.The EXOs-capturing DMCs were collected by centrifugation,achieving the separation of EXOs.Mesenchymal stem cell(MSC)-derived EXOs(MSC-EXOs)were separated by this DMC-based strategy,and the separated MSC-EXOs significantly enhanced the migration ability of cells.In particular,the significant therapeutic efficacy of the DMCs with MSC-EXOs was verified in full-thickness wound excision mouse models,in which the wounds completely healed in 10 days.We envision that this DMC-based separation strategy can be a promising route to promote the development of EXOs in biomedicine.展开更多
Although it has been developed for many years, nucleic acid aptamer screening technology still fails to be widely used, a considerable part of it is due to the variability of tumor cell morphology, which leads to the ...Although it has been developed for many years, nucleic acid aptamer screening technology still fails to be widely used, a considerable part of it is due to the variability of tumor cell morphology, which leads to the use of immortalized cell lines in the laboratory to screen nucleic acid aptamers for recognition ability of tumor cells in the diseased body.To address this, primary cells that can be stably passaged were isolated and extracted from spontaneous tumors of genetically engineered pancreatic ductal adenocarcinoma model mice in this study.Next, an automated screening instrument for nucleic acid aptamers developed autonomously by our group was used to perform efficient aptamer screening using a limited number of cells, and the obtained nucleic acid aptamers were affinity verified at the cellular level.Finally, to answer the question of the cell growth environment difference on the recognition ability of nucleic acid aptamers, we verified its targeting ability to tumors in vivo on a nude mice xenograft tumor model, and further used a common antitumor drug doxorubicin combined with nucleic acid aptamers to verify the drug loading ability of this aptamer combined with the targeting therapeutic ability.展开更多
BACKGROUND Malignant tumors are one of the leading causes of death worldwide,imposing a substantial economic and social burden.Early detection is the key to improving cure rates and reducing mortality rates,which requ...BACKGROUND Malignant tumors are one of the leading causes of death worldwide,imposing a substantial economic and social burden.Early detection is the key to improving cure rates and reducing mortality rates,which requires the development of sensitive early detection technologies.Signal amplification techniques play a crucial role in aptamer-based early detection of tumors and are increasingly garnering attention from researchers.AIM To investigate the current research status,developmental trajectories,and hotspots in signal amplification for aptamer-based tumor detection through bibliometric analysis.METHODS English publications pertaining to signal amplification in aptamer-based tumor detection were retrieved from the Web of Science Core Collection database.VOSviewer and CiteSpace software were employed to analyze various information within this field,including countries,institutions,authors,co-cited authors,journals,co-cited journals,cited references,and keywords.RESULTS A total of 757 publications were included in this study.China accounted for 85.47%of all publications,with Nanjing University(China)emerging as the institution with the highest publication output.The most influential authors and journals were Hasanzadeh M.from Iran and"Biosensors and Bioelectronics",respectively.Exosomes and carcinoembryonic antigen(CEA)stood out as the most researched tumor-related molecules.Currently,the predominant signal amplification technique,nanomaterial,and signal transduction method were identified as hybridization chain reactions,gold nanoparticles,and electrochemical methods,respectively.Over the past 3 years,exosomes,CEA,electrochemical biosensors,and nanosheets have emerged as research hotspots,exhibiting a robust burst of intensity.CONCLUSION This study is the first bibliometric analysis of literature on signal amplification in aptamer-based tumor detection and elucidates the current status,hotspots,and prospective research directions within this realm.Additionally,it provides an important reference for researchers.展开更多
Ergot alkaloids are mycotoxins which can be found in food based on cereal-crops, due to a contamination of plants by fungi of the genus Claviceps. The ingestion of ergot contaminated cereal crops can lead to a severe ...Ergot alkaloids are mycotoxins which can be found in food based on cereal-crops, due to a contamination of plants by fungi of the genus Claviceps. The ingestion of ergot contaminated cereal crops can lead to a severe poisoning known as ergotism. For food and feed safety purposes, the extraction of ergot alkaloids from ergot contaminated flour was investigated. For the specific recognition of ergot alkaloids, DNA aptamer ligands specially selected for ergot alkaloids were grafted onto silica gel in order to construct a specific solid phase extraction system. The aptamer-functionalized silica gels were used to extract ergot alkaloids from a contaminated rye feed sample. The presence of ergot alkaloids eluted from the aptamer-functionalized silica gels was analyzed using LC-QTOF-MS. By using this simple system, it was possible to specifically extract ergosine, ergokryptine and ergocornine from an ergot contaminated rye feed sample. This aptamer-based extraction tool shows the applicability of aptamers for the specific extraction of toxins or natural compounds from turbid matrices in a one-step procedure.展开更多
An operationally simple and efficient method for the synthesis of a wide range of alkylated nucleotides under mild conditions was developed. This improved method furnishes alkylated nucleotides fi＇om both single nucl...An operationally simple and efficient method for the synthesis of a wide range of alkylated nucleotides under mild conditions was developed. This improved method furnishes alkylated nucleotides fi＇om both single nucleotides and oligonucleotides, and were prepared in high yields of 81% to 91%. Alkyl modified aptamer AS1411s were synthesized using this method and the biological activity screening results demonstrated that alkylation at the 1^st P-S site on yielded stronger target protein binding capacity, greater growth suppression effects against K562 and HL-60 cell lines, and improved serum stability, as compared with AS1411. This modified aptamer may be useful in tumor detection and treatment.展开更多
Aptamers are short,single-stranded DNA or RNA molecules that selectively bind to a target molecule.Aptamercomplement duplex(ACD)is often used to design molecular switches capable of producing a detectable signal or tr...Aptamers are short,single-stranded DNA or RNA molecules that selectively bind to a target molecule.Aptamercomplement duplex(ACD)is often used to design molecular switches capable of producing a detectable signal or triggering a structural change upon aptamer binding to a target.However,such aptamer switch generally faces an increased dissociation constant(Kd)due to the energy barrier of the complementary duplex.We reported a competitive hybridization mechanism to modulate the binding affinity of an ACD to a target adenosine.Using the computation-guided design,we calculated the aptamer folding energy for the duplex length from 11-nt to 15-nt,and experimentally measured increased apparent Kd values resulted from these extended duplexes.Using a set of strands to compete with the ACD hybridization,it reduced the aptamer folding energy to facilitate aptamer switches with decreased apparent Kd values ranging from over 400μM without a competing strand to~30μM with a competing strand.This competitive aptamer switch was also found sensitive to single-nucleotide mutations of a competing strand.Our work provides an approach to modulate the binding affinity and the sensitivity of aptamer-complement duplexes,which could be useful in the nucleic acids-based sensing and nanomedicine.展开更多
Aptamers are a class of single oligonucleotide molecules(DNA or RNA)that are screened from random DNA or RNA oligonucleotide chain libraries by the systemic evolution of ligands by exponential enrichment technology.Th...Aptamers are a class of single oligonucleotide molecules(DNA or RNA)that are screened from random DNA or RNA oligonucleotide chain libraries by the systemic evolution of ligands by exponential enrichment technology.The selected aptamers are capable of specifically binding to different targeting molecules,which is achieved by the three-dimensional structure of aptamers.Aptamers are similar in function to monoclonal antibodies,and therefore,they are also referred to as"chemical antibodies".Due to their high affinity and specificity and low immunogenicity,aptamers are topics of intense interest in today's biological targeting research especially in tumor research.They not only have high potential for clinical advances in tumor targeting detection but also are highly promising as targeted tumor drug carriers for use in tumor therapy.Various experimental studies have shown that aptamer-based diagnostic and therapeutic methods for liver cancer have great potential for application.This paper summarizes the structure,characteristics,and screening methods of aptamers and reviews the recent research progress on nucleic acid aptamers in the targeted diagnosis and treatment of liver cancer.展开更多
Aflatoxin B1(AFB1)is a highly toxic mycotoxin,and rapid and sensitive detection of AFB1 is in demand for food safety and environmental analysis.Here we described a simple aptamer molecular beacon assay for rapid detec...Aflatoxin B1(AFB1)is a highly toxic mycotoxin,and rapid and sensitive detection of AFB1 is in demand for food safety and environmental analysis.Here we described a simple aptamer molecular beacon assay for rapid detection of aflatoxin B1(AFB1)by using an aptamer with a fluorescein(FAM)label at the 50 end and a fluorescence quencher(black hole quencher 1,BHQ1)at the 30 end.In the presence of AFB1,the aptamer probe bound with AFB1 and induced a hairpin structure,drawing FAM and BHQ1 into close proximity and leading to fluorescence quenching.This assay allowed for a detection limit of 3.9 nmol/L and a dynamic range from 3.9 nmol/L to 4 mmol/L.Specificity test showed other mycotoxins including ochratoxin A,ochratoxin B,fumonisin B1,fumonisin B2,and zearalenone had negligible influence on detection of AFB1.AFB1 spiked in diluted liquor wine,methanol,or corn flour samples was successfully detected by using this aptamer probe,and the assay showed potential for real sample analysis.展开更多
Bisphenol A(BPA)is one of the environmental endocrine disruptors(EDCs),and BPA contamination in environment can cause high risks to human health.Rapid determination of BPA on sites is in high demand in environmental a...Bisphenol A(BPA)is one of the environmental endocrine disruptors(EDCs),and BPA contamination in environment can cause high risks to human health.Rapid determination of BPA on sites is in high demand in environmental analysis.Taking advantage of aptamers as affinity ligands and fluorescence anisotropy(FA)analysis,we developed a simple and rapid FA assay for BPA by employing a single tetramethylrhodamine(TMR)labeled short 35-mer DNA aptamer against BPA.The assay is based on the BPA-binding induced conformation change of TMR-labeled aptamer and alteration of interaction between TMR and guanine bases,resulting in change of FA signals.We screened the FA change of aptamer probes having TMR label on a specific site of the aptamer upon BPA addition.The aptamer with a TMR label on the 22nd T base showed large FA-decreasing response to BPA and maintained good binding affinity to BPA.By using this TMR-labeled aptamer,we achieved FA detection of BPA with a detection limit of 0.5μmol/L under the optimized conditions.This assay was selective towards BPA and enabled the detection of BPA spiked in tap water sample,showing the potential applications on water samples.展开更多
The detection of bacterial pathogen such as Staphylococcus aureus(S.aureus) is essential for the regulation of food hygiene and disease diagnosis.Herein,we developed a simple one-step fluorescence resonance energy tra...The detection of bacterial pathogen such as Staphylococcus aureus(S.aureus) is essential for the regulation of food hygiene and disease diagnosis.Herein,we developed a simple one-step fluorescence resonance energy transfer(FRET)-based sensor for specific and sensitive detection of S.aureus in food and serum samples,in which aptamer-modified quantum dots(aptamer-QDs) was employed as the energy donor and antibiotic of teicoplanin functionalized-gold nanoparticles(Teico-AuNPs) was chosen as the energy acceptor.Within 1 h,the FRET-based sensor showed a linear range of from 10 cfu/mL to 5 × 10^(8) cfu/mL,with the low limit of detection(LOD,2 cfu/mL) for S.aureus in buffer.When further applied to assay S.aureus in real samples,the FRET-based sensor showed good recoveries ranging from 84.5% to 110.0%,with relative standard derivations(RSDs) of 0.01%-0.44% and a LOD of 100 cfu/mL in milk,orange juice and human serum.展开更多
基金supported by Higher Institution Centre of Excellence(HICoE)Grant(A305-KR-AKH002-0000000278-K134)from the Ministry of Higher Education,Malaysia.
文摘Objective:To assess aptamer-based assays for diagnosing latent tuberculosis infection(LTBI).Methods:Literature from Medline,ScienceDirect,and Scopus,covering publications from January 1,2012,to December 31,2023,was examined.This review evaluates different aptamers,biomarkers,sample types,sample sizes,reference assays,and the assays'sensitivity and specificity.By using the Quality Assessment of Diagnostic Accuracy Studies 2,the risk of bias in each study was evaluated.Results:Aptamer-based assays generally showed a sensitivity of 90%(95%CI:75%-100%)and specificity of 90%(95%CI:50%-100%),where optical aptasensor showed the highest sensitivity and specificity at 100%.Serum samples were frequently used to enhance antigen detectability,improving the assay’s performance.Meanwhile,HspX was the most studied biomarker,followed by MPT64,and IFN-γ.Conclusions:Aptamer-based assays could be reliable alternatives to current LTBI detection methods,but further research is needed to validate their clinical efficacy.
基金supported by National Natural Science Foundation of China(No.82002241)National Key Research and Development Program of China(No.2020YFA0909000)“Clinic Plus”Outstanding Project(No.2024ZY012)from Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine。
文摘Diabetes and insulinoma represent opposing alterations in pancreatic β-cell mass,with diabetes resulting from irreversible β-cells damage and insulinoma arising from abnormal proliferation.Early diagnosis of both conditions necessitates effectiveβ-cell mass detection.Current detection methods are limited in diagnosing each condition individually or lacking timely and accurate detection.Diabetes is typically identified only after significantβ-cell loss,while insulinoma can evade conventional imaging due to their small size.Positron emission tomography/computed tomography(PET/CT)imaging,combining anatomical and functional data,enhances diagnostic accuracy but faces challenges in specificity.This study employed two RNA aptamers(m12–3773 and 1–717)modified to enhance RNase resistance and conjugated with68Ga to create ^(68)Ga-NOTA-Ap.^(68)Ga-NOTA-Ap was administered to rats with pancreaticβ-cell damage and mice with insulinoma to evaluate its ability to image islets,detect changes in pancreatic β-cell mass(BCM),and identify insulinoma.Modified with methoxy and fluoro,RNA aptamers exhibited enhanced stability and RNases resistance while retaining their dissociation constants(K_(d)).Furthermore,^(68)Ga-NOTA-Ap effectively detected changes of BCM in rats with pancreatic β-cell damage and imaged insulinoma in mice through recognition of abnormalβ-cell proliferation by recognizing clusterin and transmembrane p24 trafficking protein 6(TMED6)on pancreaticβ-cell.The developed ^(68)Ga-NOTA-Ap shows promise for early screening of diabetes and insulinoma due to its high sensitivity,specificity,and non-invasive nature.It has potential clinical applications for monitoring pancreatic β-cell function and diagnosing insulinoma.
基金the National Natural Science Foundation of China(Nos.22104158,82174104,U1903211)the Natural Science Foundation of Hunan Province(No.2021JJ40041)+1 种基金Guangdong Basic and Applied Basic Research Foundation(No.2023A1515011346)Shenzhen Science and Technology Program(No.SZBH202130)。
文摘Heterodimerization in RTKs is of vital importance in the RTK signaling and cell functions.Heterodimerization between RTKs can result in diversity of downstream signals,increasing the ability of cells to respond to external experiments.Traditional RTKs heterodimerization always occur in the same families and is lack of agonists to activate the heterodimeric RTKs signaling pathway.Herein,we developed the DNA agonist based on bivalent aptamers for the heterodimerized RTKs of different families,AF/AM-1,which could simultaneously activate FGFR1 and c-Met signaling.It is the first agonist that realizing the heterodimerization and activation of FGFR1 and c-Met,two different RTK families.The activation of FGFR1/c-Met heterodimer result in the down-stream signals transduction,such as the phosphorylation of Akt and Erk,inducing the cell migration and proliferation.The DNA agonist for RTK heterodimer of different families would have potential applications in the fields of biomedicine.
基金Key research and development projects of Sichuan Science and Technology Plan Project(2024YFFK0135)Fujian Provincial Natural Science Foundation of China(2024J011450).
文摘Precision medicine has become a cornerstone in modern therapeutic strategies, with nucleic acid aptamers emerging aspivotal tools due to their unique properties. These oligonucleotide fragments, selected through the Systematic Evolution ofLigands by Exponential Enrichment process, exhibit high affinity and specificity toward their targets, such as DNA, RNA,proteins, and other biomolecules. Nucleic acid aptamers offer significant advantages over traditional therapeutic agents,including superior biological stability, minimal immunogenicity, and the capacity for universal chemical modifications thatenhance their in vivo performance and targeting precision. In the realm of osseous tissue repair and regeneration, a complexphysiological process essential for maintaining skeletal integrity, aptamers have shown remarkable potential in influencingmolecular pathways crucial for bone regeneration, promoting osteogenic differentiation and supporting osteoblast survival. Byengineering aptamers to regulate inflammatory responses and facilitate the proliferation and differentiation of fibroblasts,these oligonucleotides can be integrated into advanced drug delivery systems, significantly improving bone repair efficacywhile minimizing adverse effects. Aptamer-mediated strategies, including the use of siRNA and miRNA mimics or inhibitors,have shown efficacy in enhancing bone mass and microstructure. These approaches hold transformative potential for treatinga range of orthopedic conditions like osteoporosis, osteosarcoma, and osteoarthritis. This review synthesizes the molecularmechanisms and biological roles of aptamers in orthopedic diseases, emphasizing their potential to drive innovative andeffective therapeutic interventions.
文摘Aptamers are a type of single-chain oligonucleotide that can combine with a specific target.Due to their simple preparation,easy modification,stable structure and reusability,aptamers have been widely applied as biochemical sensors for medicine,food safety and environmental monitoring.However,there is little research on aptamer-target binding mechanisms,which limits their application and development.Computational simulation has gained much attention for revealing aptamer-target binding mechanisms at the atomic level.This work summarizes the main simulation methods used in the mechanistic analysis of aptamer-target complexes,the characteristics of binding between aptamers and different targets(metal ions,small organic molecules,biomacromolecules,cells,bacteria and viruses),the types of aptamer-target interactions and the factors influencing their strength.It provides a reference for further use of simulations in understanding aptamer-target binding mechanisms.
基金supported by Tianjin Health Science and Technology Research Project(No.TJWJ2021MS005)National Natural Science Foundation of China(No.22174097).
文摘Exosomes(EXOs)have showed great potential in regenerative medicine.The separation of EXOs from complex biological media is essential for the down-stream applications.Herein,we report a deoxyribonucleic acid(DNA)-based micro-complex(DMC)containing polyaptamers,which realized the specific separation of EXOs from cell culture media and the significant promotion of wound healing.The synthesis of DMCs was based on a biomineralization process via rolling circle amplification(RCA)under the catalysis of phi29 DNA polymerase.To endow DMCs with the ability to capture EXOs,the DNA template of RCA was integrated with complementary sequence of aptamer that specifically recognized the CD63 proteins on EXOs.The obtained DMCs contained polyaptamers that can specifically capture the EXOs in cell culture media.The EXOs-capturing DMCs were collected by centrifugation,achieving the separation of EXOs.Mesenchymal stem cell(MSC)-derived EXOs(MSC-EXOs)were separated by this DMC-based strategy,and the separated MSC-EXOs significantly enhanced the migration ability of cells.In particular,the significant therapeutic efficacy of the DMCs with MSC-EXOs was verified in full-thickness wound excision mouse models,in which the wounds completely healed in 10 days.We envision that this DMC-based separation strategy can be a promising route to promote the development of EXOs in biomedicine.
基金supported by the National Key Research and Development Program of China(Nos.2017YFA0205301 and 2018YFC1602905)National Natural Science Foundation of China(Nos.62071119,62075098,81902153,61527806)the Open Funding of State Key Laboratory of Oral Diseases(No.SKLOD2022OF05).
文摘Although it has been developed for many years, nucleic acid aptamer screening technology still fails to be widely used, a considerable part of it is due to the variability of tumor cell morphology, which leads to the use of immortalized cell lines in the laboratory to screen nucleic acid aptamers for recognition ability of tumor cells in the diseased body.To address this, primary cells that can be stably passaged were isolated and extracted from spontaneous tumors of genetically engineered pancreatic ductal adenocarcinoma model mice in this study.Next, an automated screening instrument for nucleic acid aptamers developed autonomously by our group was used to perform efficient aptamer screening using a limited number of cells, and the obtained nucleic acid aptamers were affinity verified at the cellular level.Finally, to answer the question of the cell growth environment difference on the recognition ability of nucleic acid aptamers, we verified its targeting ability to tumors in vivo on a nude mice xenograft tumor model, and further used a common antitumor drug doxorubicin combined with nucleic acid aptamers to verify the drug loading ability of this aptamer combined with the targeting therapeutic ability.
基金National Natural Science Foundation of China,No.82160494 and No.82160444.
文摘BACKGROUND Malignant tumors are one of the leading causes of death worldwide,imposing a substantial economic and social burden.Early detection is the key to improving cure rates and reducing mortality rates,which requires the development of sensitive early detection technologies.Signal amplification techniques play a crucial role in aptamer-based early detection of tumors and are increasingly garnering attention from researchers.AIM To investigate the current research status,developmental trajectories,and hotspots in signal amplification for aptamer-based tumor detection through bibliometric analysis.METHODS English publications pertaining to signal amplification in aptamer-based tumor detection were retrieved from the Web of Science Core Collection database.VOSviewer and CiteSpace software were employed to analyze various information within this field,including countries,institutions,authors,co-cited authors,journals,co-cited journals,cited references,and keywords.RESULTS A total of 757 publications were included in this study.China accounted for 85.47%of all publications,with Nanjing University(China)emerging as the institution with the highest publication output.The most influential authors and journals were Hasanzadeh M.from Iran and"Biosensors and Bioelectronics",respectively.Exosomes and carcinoembryonic antigen(CEA)stood out as the most researched tumor-related molecules.Currently,the predominant signal amplification technique,nanomaterial,and signal transduction method were identified as hybridization chain reactions,gold nanoparticles,and electrochemical methods,respectively.Over the past 3 years,exosomes,CEA,electrochemical biosensors,and nanosheets have emerged as research hotspots,exhibiting a robust burst of intensity.CONCLUSION This study is the first bibliometric analysis of literature on signal amplification in aptamer-based tumor detection and elucidates the current status,hotspots,and prospective research directions within this realm.Additionally,it provides an important reference for researchers.
文摘Ergot alkaloids are mycotoxins which can be found in food based on cereal-crops, due to a contamination of plants by fungi of the genus Claviceps. The ingestion of ergot contaminated cereal crops can lead to a severe poisoning known as ergotism. For food and feed safety purposes, the extraction of ergot alkaloids from ergot contaminated flour was investigated. For the specific recognition of ergot alkaloids, DNA aptamer ligands specially selected for ergot alkaloids were grafted onto silica gel in order to construct a specific solid phase extraction system. The aptamer-functionalized silica gels were used to extract ergot alkaloids from a contaminated rye feed sample. The presence of ergot alkaloids eluted from the aptamer-functionalized silica gels was analyzed using LC-QTOF-MS. By using this simple system, it was possible to specifically extract ergosine, ergokryptine and ergocornine from an ergot contaminated rye feed sample. This aptamer-based extraction tool shows the applicability of aptamers for the specific extraction of toxins or natural compounds from turbid matrices in a one-step procedure.
基金the Ministry of Science and Technology of China(Grant No.2012CB720604)National Natural Science Foundation of China(Grant No.21332010)
文摘An operationally simple and efficient method for the synthesis of a wide range of alkylated nucleotides under mild conditions was developed. This improved method furnishes alkylated nucleotides fi＇om both single nucleotides and oligonucleotides, and were prepared in high yields of 81% to 91%. Alkyl modified aptamer AS1411s were synthesized using this method and the biological activity screening results demonstrated that alkylation at the 1^st P-S site on yielded stronger target protein binding capacity, greater growth suppression effects against K562 and HL-60 cell lines, and improved serum stability, as compared with AS1411. This modified aptamer may be useful in tumor detection and treatment.
基金supported by a PECASE award to J.F.(W911NF1910240),a DoD DURIP(W911NF2010107)and a NSF MRI(2215917)J.F.is also supported by the Rutgers TechAdvance award,NJACTS-Pilot Program and NSF PFI award(2141141)D.P.and S.L.appreciate the support of Arts and Sciences Undergraduate Research Grant from the College of Arts and Sciences at Rutgers University-Camden.The authors are grateful to the Equipment Leasing Funds from the State of New Jersey.
文摘Aptamers are short,single-stranded DNA or RNA molecules that selectively bind to a target molecule.Aptamercomplement duplex(ACD)is often used to design molecular switches capable of producing a detectable signal or triggering a structural change upon aptamer binding to a target.However,such aptamer switch generally faces an increased dissociation constant(Kd)due to the energy barrier of the complementary duplex.We reported a competitive hybridization mechanism to modulate the binding affinity of an ACD to a target adenosine.Using the computation-guided design,we calculated the aptamer folding energy for the duplex length from 11-nt to 15-nt,and experimentally measured increased apparent Kd values resulted from these extended duplexes.Using a set of strands to compete with the ACD hybridization,it reduced the aptamer folding energy to facilitate aptamer switches with decreased apparent Kd values ranging from over 400μM without a competing strand to~30μM with a competing strand.This competitive aptamer switch was also found sensitive to single-nucleotide mutations of a competing strand.Our work provides an approach to modulate the binding affinity and the sensitivity of aptamer-complement duplexes,which could be useful in the nucleic acids-based sensing and nanomedicine.
文摘Aptamers are a class of single oligonucleotide molecules(DNA or RNA)that are screened from random DNA or RNA oligonucleotide chain libraries by the systemic evolution of ligands by exponential enrichment technology.The selected aptamers are capable of specifically binding to different targeting molecules,which is achieved by the three-dimensional structure of aptamers.Aptamers are similar in function to monoclonal antibodies,and therefore,they are also referred to as"chemical antibodies".Due to their high affinity and specificity and low immunogenicity,aptamers are topics of intense interest in today's biological targeting research especially in tumor research.They not only have high potential for clinical advances in tumor targeting detection but also are highly promising as targeted tumor drug carriers for use in tumor therapy.Various experimental studies have shown that aptamer-based diagnostic and therapeutic methods for liver cancer have great potential for application.This paper summarizes the structure,characteristics,and screening methods of aptamers and reviews the recent research progress on nucleic acid aptamers in the targeted diagnosis and treatment of liver cancer.
基金financial support from the National Natural Science Foundation of China(Nos.21575153,21435008,21874146)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB14030200)the Key Research Program of the Chinese Academy of Sciences(No.KFZD-SW-203)
文摘Aflatoxin B1(AFB1)is a highly toxic mycotoxin,and rapid and sensitive detection of AFB1 is in demand for food safety and environmental analysis.Here we described a simple aptamer molecular beacon assay for rapid detection of aflatoxin B1(AFB1)by using an aptamer with a fluorescein(FAM)label at the 50 end and a fluorescence quencher(black hole quencher 1,BHQ1)at the 30 end.In the presence of AFB1,the aptamer probe bound with AFB1 and induced a hairpin structure,drawing FAM and BHQ1 into close proximity and leading to fluorescence quenching.This assay allowed for a detection limit of 3.9 nmol/L and a dynamic range from 3.9 nmol/L to 4 mmol/L.Specificity test showed other mycotoxins including ochratoxin A,ochratoxin B,fumonisin B1,fumonisin B2,and zearalenone had negligible influence on detection of AFB1.AFB1 spiked in diluted liquor wine,methanol,or corn flour samples was successfully detected by using this aptamer probe,and the assay showed potential for real sample analysis.
基金supported by the National Natural Science Foundation of China(Nos.21874146,21575153,21435008)。
文摘Bisphenol A(BPA)is one of the environmental endocrine disruptors(EDCs),and BPA contamination in environment can cause high risks to human health.Rapid determination of BPA on sites is in high demand in environmental analysis.Taking advantage of aptamers as affinity ligands and fluorescence anisotropy(FA)analysis,we developed a simple and rapid FA assay for BPA by employing a single tetramethylrhodamine(TMR)labeled short 35-mer DNA aptamer against BPA.The assay is based on the BPA-binding induced conformation change of TMR-labeled aptamer and alteration of interaction between TMR and guanine bases,resulting in change of FA signals.We screened the FA change of aptamer probes having TMR label on a specific site of the aptamer upon BPA addition.The aptamer with a TMR label on the 22nd T base showed large FA-decreasing response to BPA and maintained good binding affinity to BPA.By using this TMR-labeled aptamer,we achieved FA detection of BPA with a detection limit of 0.5μmol/L under the optimized conditions.This assay was selective towards BPA and enabled the detection of BPA spiked in tap water sample,showing the potential applications on water samples.
基金supported by the National Natural Science Foundation of China (Nos.21974110,21575118,21976145 and 31672605)Natural Science Foundation Project of Chongqing (No.CSTC2019jcyj-msxmX0406)。
文摘The detection of bacterial pathogen such as Staphylococcus aureus(S.aureus) is essential for the regulation of food hygiene and disease diagnosis.Herein,we developed a simple one-step fluorescence resonance energy transfer(FRET)-based sensor for specific and sensitive detection of S.aureus in food and serum samples,in which aptamer-modified quantum dots(aptamer-QDs) was employed as the energy donor and antibiotic of teicoplanin functionalized-gold nanoparticles(Teico-AuNPs) was chosen as the energy acceptor.Within 1 h,the FRET-based sensor showed a linear range of from 10 cfu/mL to 5 × 10^(8) cfu/mL,with the low limit of detection(LOD,2 cfu/mL) for S.aureus in buffer.When further applied to assay S.aureus in real samples,the FRET-based sensor showed good recoveries ranging from 84.5% to 110.0%,with relative standard derivations(RSDs) of 0.01%-0.44% and a LOD of 100 cfu/mL in milk,orange juice and human serum.
