Objective This study aimed to characterize the diagnostic and vaccine potential of a novel Mycobacterium tuberculosisantigen Rv0674. Methods To evaluate thediagnostic potential and antigenicity of Rv0674, IgG was eval...Objective This study aimed to characterize the diagnostic and vaccine potential of a novel Mycobacterium tuberculosisantigen Rv0674. Methods To evaluate thediagnostic potential and antigenicity of Rv0674, IgG was evaluated using ELISA and interferon (IFN)-γ was done by using ELISpot assay among TB patients and healthy donors. For immunogenicity evaluation, BALB/c mice were immunized with Rv0674. Cytokine production was determined by cytokine release assay using an ELISA kit, and the antibodies were tested using ELISA. Results The results of serum Elisa tests showed that Rv0674 specific immunoglobulin G (IgG) response was higher in TB patients than negative controls. And Rv0674 had good performance in serological test with sensitivity and specificity of 77.1% and 81.1%, respectively. While it shows poor sensitivity and specificity of 26.23% and 79.69% for IFN-γ tests. In BALB/c mice, Rv0674 adjuvant by DDA/PolyI:C could also induce a high level of IFN-γ, interleukin-2 and interleukin-6 as well as a high IgG titer in both high-and low-dose groups indicating that Rv0674 is essential in humoral and cellular immunity. Moreover, the cytokine profile and IgG isotypecharacterized Rv0674 as a Th1/Th2-mixed-type protective immunity with the predominance of Th1 cytokines. Conclusion Rv0674 may be a good potential candidate for the development of TB serological diagnosis and a new TB vaccine.展开更多
A fundamental goal in cellular signaling is to understand allosteric communication, the process by which sig-nals originating at one site in a protein propagate reliably to affect distant functional sites. The general...A fundamental goal in cellular signaling is to understand allosteric communication, the process by which sig-nals originating at one site in a protein propagate reliably to affect distant functional sites. The general principles of protein structure that underlie this process remain unknown. Statistical coupling analysis （SCA） is a statistical technique that uses evolutionary data of a protein family to measure correlation between distant functional sites and suggests allosteric communication. In proteins, very distant and small interactions between collections of amino acids provide the communication which can be important for signaling process. In this paper, we present the SCA of protein alignment of the esterase family （pfam ID： PF00756） containing the sequence of antigen 85C secreted by Mycobacterium tuberculosis to identify a subset of interacting residues. Clustering analysis of the pairwise correlation highlighted seven important residue positions in the esterase family alignments. These resi-dues were then mapped on the crystal structure of antigen 85C （PDB ID： 1DQZ）. The mapping revealed corre-lation between 3 distant residues （Asp38, Leu123 and Met125） and suggests allosteric communication between them. This information can be used for a new drug against this fatal disease.展开更多
Background: A new rapid Immunochromatographic test (ICT) kit (MPT64 TB Ag Kit) for detection of MPT64 Antigen in M. tuberculosis (MTB) isolates used for rapid identification of MTB isolates developed by SD (Standard D...Background: A new rapid Immunochromatographic test (ICT) kit (MPT64 TB Ag Kit) for detection of MPT64 Antigen in M. tuberculosis (MTB) isolates used for rapid identification of MTB isolates developed by SD (Standard Diagnostics) Bio line, South Korea was evaluated. The ICT is a rapid, reliable and cheaper method that can be used instead of conventional biochemical tests for confirming MTB in culture isolates in resource limited laboratories. The study also evaluated the ability of ICT to detect MPT64-Antigen before the micro MGIT could signal positive. Material/Methods: A total of 450 sputum samples of individual patients were used for the study. 152 isolates of Mycobacteria were recovered from solid and liquid media. These strains were tested for the detection of MPT64-antigen. H37Rv strain was served as the positive reference control and also used for early detection of Antigen experiment. Findings: The development of bands on both test and sample region when H37Rv strain was tested were seen (MPT64 antigen positive). When 138 MTB isolates were tested, it showed a similar banding pattern indicating 100% sensitivity. MPT64 band formation was not detected in any of the 14 isolates indicating 100% specificity. Both PPV & NPV were 100%. All the isolates negative for MPT64 Ag were confirmed as MOTT by conventional bio-chemical PNBA. The H37Rv strain showed a faint band from the 2nd day onwards from inoculation till 3rd day in the earlier Antigen detection experiment. Conclusion: Rapid identification of MTB culture isolate is a pressing need for diagnosis and proceeding to perform drug susceptibility testing. MPT64 TB Ag detection ICT kit is a rapid, reliable method, good substitute for molecular identification methods, and conventional biochemical test which is time-consuming and technically demanding. The early detection of Antigen can be used as an effective tool in diagnosis.展开更多
Extracellular vesicles(EVs)are cystic vesicles naturally released by most mammalian cells and bacteria.EV contents include proteins,lipids,and nucleic acids.EVs can act as messengers to transmit a variety of molecules...Extracellular vesicles(EVs)are cystic vesicles naturally released by most mammalian cells and bacteria.EV contents include proteins,lipids,and nucleic acids.EVs can act as messengers to transmit a variety of molecules to recipient cells and thus play important regulatory roles in intercellular signal transduction.EVs,released by either a host cell or a pathogen,can carry pathogen-associated antigens and thus act as modulators of immune responses.EVs derived from Mycobacterium tuberculosis(Mtb)-infected cells can regulate the innate immune response through various pathways,such as regulating the release of inflammatory cytokines.In addition,EVs can mediate antigen presentation and regulate the adaptive immune response by transmitting immunoregulatory molecules to T helper cells.In this review,we summarize the regulatory roles of EVs in the immune response against Mtb.展开更多
Background: The concomitant presence of intestinal parasite infections (IP) and tuberculosis (TB) has relevance. M. tuberculosis immune response is associated with type 1 T helper cell (Th1) while IP is associated wit...Background: The concomitant presence of intestinal parasite infections (IP) and tuberculosis (TB) has relevance. M. tuberculosis immune response is associated with type 1 T helper cell (Th1) while IP is associated with type Th2 cell. However, there are several contradictory reports on cytokine production under coinfection and this could be in association to the mycobacterial antigens used in the studies. Aim: To get insight into the effects of different M. tuberculosis-specific antigens (ESAT-6/CFP-10 and 38 kDa/CFP-10) in generating of appropriate cytokines on peripheral blood mononuclear cells of IPTB co infected patients. Method: ELISA assessed IFN-γ and other 16 cytokines production and plasm IgE. In 18 months, we documented demographic, economic, clinical characteristics and IP frequency in individuals from Brazil. Results: An overall 10/35 (28.5%) were IPTB co infected and 40/76 (52.6%;p = 0.024) asymptomatic intestinal parasite infected community controls (IPCC). Endo-limax nana (40%) and Entamoeba coli (22%), were the most nonpathogenic protozoan identified and Entamoeba histolytica, Giardia intestinalis, Ascaris lumbricoides and Strongyloides stercoralis were the pathogenic species (40%). IgE was higher in IPCC (p = 0.036). Cytokine profiles were significantly biased toward a Th2 type IL-5 (p = 0.001) and IL-13 (p = 0.033), pro-inflammatory GM-CSF (p = 0.019) and borderline lower IL-1β in IPTB, all associated with ESAT-6/CFP-10, while IL-7 was borderline lower, but 38 kDa/CFP-10 associated;as well as IL-8 higher (p < 0.049) vs CC/IPCC. The TB/IPTB IFN-γ levels were similar to both antigens stimuli (p ≥ 0.208). Conclusion: Therefore, coin-cident IPTB coinfection did not exert a significant inhibitory effect in IFN-γ production in response to either of the two antigens, but the partial discrepancy in Th1/Th2 response, is associated with the antigen priming cells.展开更多
Objectives To evaluate the immunogenicity of Mycobacterium intracellulare proteins and determine the cross-reactive proteins between M.intracellulare and M.tuberculosis.Methods Protein extracts from M.intracellulare w...Objectives To evaluate the immunogenicity of Mycobacterium intracellulare proteins and determine the cross-reactive proteins between M.intracellulare and M.tuberculosis.Methods Protein extracts from M.intracellulare were used to immunize BALB/c mice.The antigens were evaluated using cellular and humoral immunoassays.The common genes between M.intracellular and M.tuberculosis were identified using genome-wide comparative analysis,and cross-reactive proteins were screened using immunoproteome microarrays.Results Immunization with M.intracellulare proteins induced significantly higher levels of the cytokines interferon-γ(IFN-γ),interleukin-2(IL-2),interleukin-12(IL-12),interleukin-6(IL-6)and immunoglobulins IgG,IgG1,IgM,and IgG2a in mouse serum.Bone marrow-derived macrophages isolated from mice immunized with M.intracellulare antigens displayed significantly lower bacillary loads than those isolated from mice immunized with adjuvants.Whole-genome sequence analysis revealed 396 common genes between M.intracellulare and M.tuberculosis.Microchip hybridization with M.tuberculosis proteins revealed the presence of 478 proteins in the serum of mice immunized with M.intracellulare protein extracts.Sixty common antigens were found using both microchip and genomic comparative analyses.Conclusion This is the advanced study to investigate the immunogenicity of M.intracellulare proteins and the cross-reactive proteins between M.intracellulare and M.tuberculosis.The results revealed the presence of a number of cross-reactive proteins between M.intracellulare and M.tuberculosis.Therefore,this study provides a new way of identifying immunogenic proteins for use in tuberculosis vaccines against both M.intracellulare and M.tuberculosis in future.展开更多
Background: Differential diagnosis of active tuberculosis (ATB) and latent tuberculosis infection (LTBI) has been a challenge for clinicians in high TB burden countries. The purpose of this study was to improve the ac...Background: Differential diagnosis of active tuberculosis (ATB) and latent tuberculosis infection (LTBI) has been a challenge for clinicians in high TB burden countries. The purpose of this study was to improve the accuracy of differential diagnosis of ATB and LTBI by using fluorescent immunospot (FluoroSpot) assay to detect specific Th1 cell immune responses. The novelmycobacterium tuberculosis (MTB) latency-associated antigens Rv1733c and synthetic long peptides derived from Rv1733c (Rv1733c SLP) were used based on virulence factors early secreting antigen target-6 (ESAT-6) and culture filtrate protein-10 (CFP-10).Methods: Fifty-seven ATB cases, including 20 pathogen-confirmed ATB and 37 clinically diagnosed ATB, and 36 LTBI cases, were enrolled between January and December 2017. FluoroSpot assay was used to detect the interferon γ (IFN-γ) and interleukin 2 (IL-2) secreted by the specific T cells after being stimulated with MTB virulence factors ESAT-6 and CFP-10, MTB latency-associated antigens Rv1733c and Rv1733c SLP. The receiver operating characteristic (ROC) curve was used to define the best cutoff value of latency-associated antigens in the use of differentiating ATB and LTBI. The sensitivity, specificity, predictive value, and likelihood ratio of ESAT-6 and CFP-10-FluoroSpot combined with latency-associated antigen in the differential diagnosis of ATB and LTBI were also calculated.Results: Following the stimulation with Rv1733c and Rv1733c SLP, the frequency of single IL-2-secreting T cells stimulated by Rv1733c SLP had the largest area under the ROC curve, which was 0.766. With a cutoff value of 1 (spot-forming cells [SFCs]/2.5 × 105 peripheral blood mononuclear cells) for frequency, the sensitivity and specificity of distinguishing ATB from LTBI were 72.2% and 73.7%, respectively. ESAT-6 and CFP-10-FluoroSpot detected the frequency and proportion of single IFN-γ-secreting T cells;the sensitivity and specificity of distinguishing ATB from LTBI were 82.5% and 66.7%, respectively. Combined with the frequency of single IL-2-secreting T cells stimulated by Rv1733c SLP on the basis of ESAT-6 and CFP-10-FluoroSpot, the sensitivity and specificity increased to 84.2% and 83.3%, respectively.Conclusion: Rv1733c SLP, combined with ESAT-6 and CFP-10, might be used as a candidate antigen for T cell-based tuberculosis diagnostic tests to differentiate ATB from LTBI.展开更多
Objective To select and identify the specific and protective antigens of Mycobacterium tuberculosis (M. tuberculosis) for searching a new approach to diagnose and treat tuberculosis Methods Extract and culture filt...Objective To select and identify the specific and protective antigens of Mycobacterium tuberculosis (M. tuberculosis) for searching a new approach to diagnose and treat tuberculosis Methods Extract and culture filtrates of M tuberculosis were obtained by ultrasonic treatment and millipore membrane filtration, respectively The protein samples were tested with monoclonal antibody (MAb) and patient sera The proteins showing positive reaction were sequenced on Beckman /LF 3200/peptide amino acid sequencer Results Proteins of M tuberculosis with molecular weight of 31?ku and 30?ku showed positive results when reacted with anti M tuberculosis MAb and sera of tuberculosis patients, but not with normal mouse serum and healthy human sera N terminal sequences of the 31?ku and 30?ku antigen were Ala Glu Val Asp Trp Leu Val Phe Ala Val and Phe Ser Arg Pro Gly Leu Pro Val Glu Try respectively Conclusion 31?ku and 30?ku proteins of M tuberculosis are immune protective proteins They play important or dominant roles in determination of immunorecognization展开更多
The study and characterization of biomolecules involved in the interaction between mycobacteria and their hosts are crucial to determine their roles in the invasion process and provide basic knowledge about the biolog...The study and characterization of biomolecules involved in the interaction between mycobacteria and their hosts are crucial to determine their roles in the invasion process and provide basic knowledge about the biology and pathogenesis of disease.Promising new biomarkers for diagnosis and immunotherapy have emerged recently.Mycobacterium is an ancient pathogen that has developed complex strategies for its persistence in the host and environment,likely based on the complexity of the network of interactions between the molecules involved in infection.Several biomarkers have received recent attention in the process of developing rapid and reliable detection techniques for tuberculosis.Among the most widely investigated antigens are CFP-10(10-kDa culture filtrate protein),ESAT-6(6-kD a early secretory antigenic target),Ag85 A,Ag85 B,CFP-7,and PPE18.Some of these antigens have been proposed as biomarkers to assess the key elements of the response to infection of both the pathogen and host.The design of novel and accurate diagnostic methods is essential for the control of tuberculosis worldwide.Presently,the diagnostic methods are based on the identification of molecules in the humoral response in infected individuals.Therefore,these tests depend on the capacity of the host to develop an immune response,which usually is heterogeneous.In the last 20 years,special attention has been given to the design of multiantigenic diagnostic methods to improve the levels of sensitivity and specificity.In this review,we summarize the state of the art in the study and use of mycobacterium biomolecules with the potential to support novel tuberculosis control strategies.展开更多
基金National Science and Technology Major Project of China [2018ZX10731301-002]
文摘Objective This study aimed to characterize the diagnostic and vaccine potential of a novel Mycobacterium tuberculosisantigen Rv0674. Methods To evaluate thediagnostic potential and antigenicity of Rv0674, IgG was evaluated using ELISA and interferon (IFN)-γ was done by using ELISpot assay among TB patients and healthy donors. For immunogenicity evaluation, BALB/c mice were immunized with Rv0674. Cytokine production was determined by cytokine release assay using an ELISA kit, and the antibodies were tested using ELISA. Results The results of serum Elisa tests showed that Rv0674 specific immunoglobulin G (IgG) response was higher in TB patients than negative controls. And Rv0674 had good performance in serological test with sensitivity and specificity of 77.1% and 81.1%, respectively. While it shows poor sensitivity and specificity of 26.23% and 79.69% for IFN-γ tests. In BALB/c mice, Rv0674 adjuvant by DDA/PolyI:C could also induce a high level of IFN-γ, interleukin-2 and interleukin-6 as well as a high IgG titer in both high-and low-dose groups indicating that Rv0674 is essential in humoral and cellular immunity. Moreover, the cytokine profile and IgG isotypecharacterized Rv0674 as a Th1/Th2-mixed-type protective immunity with the predominance of Th1 cytokines. Conclusion Rv0674 may be a good potential candidate for the development of TB serological diagnosis and a new TB vaccine.
文摘A fundamental goal in cellular signaling is to understand allosteric communication, the process by which sig-nals originating at one site in a protein propagate reliably to affect distant functional sites. The general principles of protein structure that underlie this process remain unknown. Statistical coupling analysis （SCA） is a statistical technique that uses evolutionary data of a protein family to measure correlation between distant functional sites and suggests allosteric communication. In proteins, very distant and small interactions between collections of amino acids provide the communication which can be important for signaling process. In this paper, we present the SCA of protein alignment of the esterase family （pfam ID： PF00756） containing the sequence of antigen 85C secreted by Mycobacterium tuberculosis to identify a subset of interacting residues. Clustering analysis of the pairwise correlation highlighted seven important residue positions in the esterase family alignments. These resi-dues were then mapped on the crystal structure of antigen 85C （PDB ID： 1DQZ）. The mapping revealed corre-lation between 3 distant residues （Asp38, Leu123 and Met125） and suggests allosteric communication between them. This information can be used for a new drug against this fatal disease.
文摘Background: A new rapid Immunochromatographic test (ICT) kit (MPT64 TB Ag Kit) for detection of MPT64 Antigen in M. tuberculosis (MTB) isolates used for rapid identification of MTB isolates developed by SD (Standard Diagnostics) Bio line, South Korea was evaluated. The ICT is a rapid, reliable and cheaper method that can be used instead of conventional biochemical tests for confirming MTB in culture isolates in resource limited laboratories. The study also evaluated the ability of ICT to detect MPT64-Antigen before the micro MGIT could signal positive. Material/Methods: A total of 450 sputum samples of individual patients were used for the study. 152 isolates of Mycobacteria were recovered from solid and liquid media. These strains were tested for the detection of MPT64-antigen. H37Rv strain was served as the positive reference control and also used for early detection of Antigen experiment. Findings: The development of bands on both test and sample region when H37Rv strain was tested were seen (MPT64 antigen positive). When 138 MTB isolates were tested, it showed a similar banding pattern indicating 100% sensitivity. MPT64 band formation was not detected in any of the 14 isolates indicating 100% specificity. Both PPV & NPV were 100%. All the isolates negative for MPT64 Ag were confirmed as MOTT by conventional bio-chemical PNBA. The H37Rv strain showed a faint band from the 2nd day onwards from inoculation till 3rd day in the earlier Antigen detection experiment. Conclusion: Rapid identification of MTB culture isolate is a pressing need for diagnosis and proceeding to perform drug susceptibility testing. MPT64 TB Ag detection ICT kit is a rapid, reliable method, good substitute for molecular identification methods, and conventional biochemical test which is time-consuming and technically demanding. The early detection of Antigen can be used as an effective tool in diagnosis.
基金Natural Science Foundation of the Inner Mongolia Autonomous Region for Distinguished Young Scholars,No.2020JQ07General Programs of Natural Science Foundation of the Inner Mongolia Autonomous Region,No.2020MS08126and"Zhiyuan"Talent Project of the Inner Mongolia Medical University,No.ZY0130013.
文摘Extracellular vesicles(EVs)are cystic vesicles naturally released by most mammalian cells and bacteria.EV contents include proteins,lipids,and nucleic acids.EVs can act as messengers to transmit a variety of molecules to recipient cells and thus play important regulatory roles in intercellular signal transduction.EVs,released by either a host cell or a pathogen,can carry pathogen-associated antigens and thus act as modulators of immune responses.EVs derived from Mycobacterium tuberculosis(Mtb)-infected cells can regulate the innate immune response through various pathways,such as regulating the release of inflammatory cytokines.In addition,EVs can mediate antigen presentation and regulate the adaptive immune response by transmitting immunoregulatory molecules to T helper cells.In this review,we summarize the regulatory roles of EVs in the immune response against Mtb.
文摘Background: The concomitant presence of intestinal parasite infections (IP) and tuberculosis (TB) has relevance. M. tuberculosis immune response is associated with type 1 T helper cell (Th1) while IP is associated with type Th2 cell. However, there are several contradictory reports on cytokine production under coinfection and this could be in association to the mycobacterial antigens used in the studies. Aim: To get insight into the effects of different M. tuberculosis-specific antigens (ESAT-6/CFP-10 and 38 kDa/CFP-10) in generating of appropriate cytokines on peripheral blood mononuclear cells of IPTB co infected patients. Method: ELISA assessed IFN-γ and other 16 cytokines production and plasm IgE. In 18 months, we documented demographic, economic, clinical characteristics and IP frequency in individuals from Brazil. Results: An overall 10/35 (28.5%) were IPTB co infected and 40/76 (52.6%;p = 0.024) asymptomatic intestinal parasite infected community controls (IPCC). Endo-limax nana (40%) and Entamoeba coli (22%), were the most nonpathogenic protozoan identified and Entamoeba histolytica, Giardia intestinalis, Ascaris lumbricoides and Strongyloides stercoralis were the pathogenic species (40%). IgE was higher in IPCC (p = 0.036). Cytokine profiles were significantly biased toward a Th2 type IL-5 (p = 0.001) and IL-13 (p = 0.033), pro-inflammatory GM-CSF (p = 0.019) and borderline lower IL-1β in IPTB, all associated with ESAT-6/CFP-10, while IL-7 was borderline lower, but 38 kDa/CFP-10 associated;as well as IL-8 higher (p < 0.049) vs CC/IPCC. The TB/IPTB IFN-γ levels were similar to both antigens stimuli (p ≥ 0.208). Conclusion: Therefore, coin-cident IPTB coinfection did not exert a significant inhibitory effect in IFN-γ production in response to either of the two antigens, but the partial discrepancy in Th1/Th2 response, is associated with the antigen priming cells.
基金supported by National Science and Technology Major Project of China[2018ZX10731301-002]。
文摘Objectives To evaluate the immunogenicity of Mycobacterium intracellulare proteins and determine the cross-reactive proteins between M.intracellulare and M.tuberculosis.Methods Protein extracts from M.intracellulare were used to immunize BALB/c mice.The antigens were evaluated using cellular and humoral immunoassays.The common genes between M.intracellular and M.tuberculosis were identified using genome-wide comparative analysis,and cross-reactive proteins were screened using immunoproteome microarrays.Results Immunization with M.intracellulare proteins induced significantly higher levels of the cytokines interferon-γ(IFN-γ),interleukin-2(IL-2),interleukin-12(IL-12),interleukin-6(IL-6)and immunoglobulins IgG,IgG1,IgM,and IgG2a in mouse serum.Bone marrow-derived macrophages isolated from mice immunized with M.intracellulare antigens displayed significantly lower bacillary loads than those isolated from mice immunized with adjuvants.Whole-genome sequence analysis revealed 396 common genes between M.intracellulare and M.tuberculosis.Microchip hybridization with M.tuberculosis proteins revealed the presence of 478 proteins in the serum of mice immunized with M.intracellulare protein extracts.Sixty common antigens were found using both microchip and genomic comparative analyses.Conclusion This is the advanced study to investigate the immunogenicity of M.intracellulare proteins and the cross-reactive proteins between M.intracellulare and M.tuberculosis.The results revealed the presence of a number of cross-reactive proteins between M.intracellulare and M.tuberculosis.Therefore,this study provides a new way of identifying immunogenic proteins for use in tuberculosis vaccines against both M.intracellulare and M.tuberculosis in future.
基金This study was supported by grants from the National Science and Technology Major Project of China(No.2017ZX10201302)the Chinese Academy of Medical Sciences Initiative for Innovative Medicine(Nos.2016-I2M-1-013,2019-I2M-2-005)。
文摘Background: Differential diagnosis of active tuberculosis (ATB) and latent tuberculosis infection (LTBI) has been a challenge for clinicians in high TB burden countries. The purpose of this study was to improve the accuracy of differential diagnosis of ATB and LTBI by using fluorescent immunospot (FluoroSpot) assay to detect specific Th1 cell immune responses. The novelmycobacterium tuberculosis (MTB) latency-associated antigens Rv1733c and synthetic long peptides derived from Rv1733c (Rv1733c SLP) were used based on virulence factors early secreting antigen target-6 (ESAT-6) and culture filtrate protein-10 (CFP-10).Methods: Fifty-seven ATB cases, including 20 pathogen-confirmed ATB and 37 clinically diagnosed ATB, and 36 LTBI cases, were enrolled between January and December 2017. FluoroSpot assay was used to detect the interferon γ (IFN-γ) and interleukin 2 (IL-2) secreted by the specific T cells after being stimulated with MTB virulence factors ESAT-6 and CFP-10, MTB latency-associated antigens Rv1733c and Rv1733c SLP. The receiver operating characteristic (ROC) curve was used to define the best cutoff value of latency-associated antigens in the use of differentiating ATB and LTBI. The sensitivity, specificity, predictive value, and likelihood ratio of ESAT-6 and CFP-10-FluoroSpot combined with latency-associated antigen in the differential diagnosis of ATB and LTBI were also calculated.Results: Following the stimulation with Rv1733c and Rv1733c SLP, the frequency of single IL-2-secreting T cells stimulated by Rv1733c SLP had the largest area under the ROC curve, which was 0.766. With a cutoff value of 1 (spot-forming cells [SFCs]/2.5 × 105 peripheral blood mononuclear cells) for frequency, the sensitivity and specificity of distinguishing ATB from LTBI were 72.2% and 73.7%, respectively. ESAT-6 and CFP-10-FluoroSpot detected the frequency and proportion of single IFN-γ-secreting T cells;the sensitivity and specificity of distinguishing ATB from LTBI were 82.5% and 66.7%, respectively. Combined with the frequency of single IL-2-secreting T cells stimulated by Rv1733c SLP on the basis of ESAT-6 and CFP-10-FluoroSpot, the sensitivity and specificity increased to 84.2% and 83.3%, respectively.Conclusion: Rv1733c SLP, combined with ESAT-6 and CFP-10, might be used as a candidate antigen for T cell-based tuberculosis diagnostic tests to differentiate ATB from LTBI.
文摘Objective To select and identify the specific and protective antigens of Mycobacterium tuberculosis (M. tuberculosis) for searching a new approach to diagnose and treat tuberculosis Methods Extract and culture filtrates of M tuberculosis were obtained by ultrasonic treatment and millipore membrane filtration, respectively The protein samples were tested with monoclonal antibody (MAb) and patient sera The proteins showing positive reaction were sequenced on Beckman /LF 3200/peptide amino acid sequencer Results Proteins of M tuberculosis with molecular weight of 31?ku and 30?ku showed positive results when reacted with anti M tuberculosis MAb and sera of tuberculosis patients, but not with normal mouse serum and healthy human sera N terminal sequences of the 31?ku and 30?ku antigen were Ala Glu Val Asp Trp Leu Val Phe Ala Val and Phe Ser Arg Pro Gly Leu Pro Val Glu Try respectively Conclusion 31?ku and 30?ku proteins of M tuberculosis are immune protective proteins They play important or dominant roles in determination of immunorecognization
基金Project supported by the Consejo Nacional de Ciencia y Tecnología(CONACYT,No.284118),México。
文摘The study and characterization of biomolecules involved in the interaction between mycobacteria and their hosts are crucial to determine their roles in the invasion process and provide basic knowledge about the biology and pathogenesis of disease.Promising new biomarkers for diagnosis and immunotherapy have emerged recently.Mycobacterium is an ancient pathogen that has developed complex strategies for its persistence in the host and environment,likely based on the complexity of the network of interactions between the molecules involved in infection.Several biomarkers have received recent attention in the process of developing rapid and reliable detection techniques for tuberculosis.Among the most widely investigated antigens are CFP-10(10-kDa culture filtrate protein),ESAT-6(6-kD a early secretory antigenic target),Ag85 A,Ag85 B,CFP-7,and PPE18.Some of these antigens have been proposed as biomarkers to assess the key elements of the response to infection of both the pathogen and host.The design of novel and accurate diagnostic methods is essential for the control of tuberculosis worldwide.Presently,the diagnostic methods are based on the identification of molecules in the humoral response in infected individuals.Therefore,these tests depend on the capacity of the host to develop an immune response,which usually is heterogeneous.In the last 20 years,special attention has been given to the design of multiantigenic diagnostic methods to improve the levels of sensitivity and specificity.In this review,we summarize the state of the art in the study and use of mycobacterium biomolecules with the potential to support novel tuberculosis control strategies.
