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1.
BMC Infect Dis ; 24(1): 7, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166793

RESUMO

BACKGROUND: About 8% of TB cases worldwide are estimated to have rifampicin-susceptible, isoniazid-resistant tuberculosis (Hr-TB), ranging from 5 to 11% regions. However, Hr-TB has not received much attention while comparing to be given high priority to the management of rifampicin-resistant tuberculosis (RR-TB). This study aimed to compare the differences of treatment effects for Hr-TB and RR-TB, so as to intensify the treatment and management of Hr-TB. METHODS: A retrospective study was used to collect bacteriologically positive retreated patients with isoniazid/rifampicin resistant pulmonary tuberculosis, who were conducted at 29 tuberculosis control institutions in China from July 2009 to June 2021. We assessed effectiveness and safety of retreated patients with isoniazid/ rifampicin resistant pulmonary tuberculosis. RESULTS: A total of 147 with either positive smear or cultures were enrolled, and 80 cases were in Hr-TB group and 67 cases were in RR-TB group. There was no significant difference in terms of age, sex, body mass, type of retreatment and comorbid diabetes between the two groups (P > 0.05). The rate of number of lesions involving lung fields ≥ 3 in Hr-TB group 75.9% (60/79) was significantly higher than RR-TB group 56.7% (38/67) (χ2 = 6.077, P = 0.014). There was no statistically significant difference (P = 0.166) with regard to the treatment outcomes of the two groups, the cure rates were 54.7% (41/75) and 53.6% (30/56), respectively, and the failure rate in Hr-TB group 22.7% (17/75) was 10% higher than RR-TB group 10.7% (6/56). The rate of negative sputum smear at the end of the second month (65.7%) in the Hr-TB group was significantly lower than that in the RR-TB group (85.7%) (P = 0.025). There were no significant differences in the incidences of serious adverse reactions and chest X-ray changes between the two groups (P > 0.05). During the 5-year follow-up, recurrence in the Hr-TB group (7 cases, 14.9%) was no significantly lower than that in the RR-TB group (4 cases, 11.8%) (P = 0.754). CONCLUSION: The treatment of retreated Hr-TB patients was difficult and could be statistically similar or considerably worse than RR-TB. It's urgent to conduct further evaluation of the treatment status quo to guide the guideline development and clinical practice of Hr-TB patients.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose Pulmonar , Humanos , Rifampina/uso terapêutico , Isoniazida/uso terapêutico , Antituberculosos/uso terapêutico , Estudos Retrospectivos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Pulmonar/tratamento farmacológico , Resultado do Tratamento
2.
Zhonghua Jie He He Hu Xi Za Zhi ; 38(12): 886-91, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-26850888

RESUMO

OBJECTIVE: To analyze the therapeutic effects of the standard regimen and the optimized regimen in retreatment pulmonary tuberculosis complicated with diabetes mellitus (DM). METHODS: In a multi-center cohort study, patients with smear positive retreatment pulmonary tuberculosis (TB) with DM and those without DM [excluding multi-drug resistance (MDR), extensively drug-resistant (XDR) and non-tuberculosis Mycobacterium pulmonary disease(NTM)] were enrolled. There were a total of 178 cases, including 60 smear positive retreatment TB patients with DM and 118 without DM, who were randomly divided into 4 groups: Optimized group 1 [individualized treatment in 30 DM cases, 29 males, age (48 ± 11)], retreatment group 1 [standard retreatment regimen in 30 DM cases, 28 males, age(48 ± 10)], Optimized group 2[individual regimen in 57 non-DM cases, 37 males, age (41 ± 14)], and retreatment group 2 [standard retreatment regimen in 61 non-DM cases, 49 males, age (43 ± 13)]. Patients in the optimized group were treated with optimized individualized regimen based on DST result, with 3-4 sensitive drugs in the regimen, while those in the retreatment group were treated with national standard retreatment regimen. The therapeutic effect of different groups were recorded and the related factors of treatment outcome were analyzed with Chi-square test and multi-factor analysis. RESULTS: The treatment success rates of the optimized group 1 and the retreatment group 1 were 83.3%(25/30) and 60.0%(18/30), respectively, and the difference was statistically significant (χ(2)=4.02, P=0.045<0.05). The treatment failure rate of the optimized group 1 (6.7%, 2/30) and the retreatment group 1(30.0%, 9/30) was statistically different (χ(2)=5.46, P=0.02<0.05). The outcome difference between the optimized group 2 and the retreatment group 2 showed no statistical significance. Multi-factor analysis showed that treatment regimen, DM, gender and drug resistance were the significant factors related with treatment outcome. The probability of treatment success using the individualized treatment regimen was 2.7 times higher than that using the standard regimen (P=0.025). The risk of treatment failure of the drug resistance cases was 2.8 times higher than that of the drug sensitive cases (P=0.038). The probability of treatment success in DM cases was 0.4 times that in non-DM cases (P<0.05). CONCLUSION: The outcome of the optimized regimen group was better than that of the standard regimen group, and retreatment TB patients complicated with DM faced a higher risk of treatment failure, which should receive more attention.


Assuntos
Complicações do Diabetes , Tuberculose Pulmonar , Adulto , Estudos de Coortes , Diabetes Mellitus , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retratamento , Resultado do Tratamento
3.
J Infect ; 86(5): 421-438, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37003521

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb) infection, is currently the deadliest infectious disease in human that can evolve to severe forms. A comprehensive immune landscape for Mtb infection is critical for achieving TB cure, especially for severe TB patients. We performed single-cell RNA transcriptome and T-cell/B-cell receptor (TCR/BCR) sequencing of 213,358 cells from 27 samples, including 6 healthy donors and 21 active TB patients with varying severity (6 mild, 6 moderate and 9 severe cases). Two published profiles of latent TB infection were integrated for the analysis. We observed an obviously elevated proportion of inflammatory immune cells (e.g., monocytes), as well as a markedly decreased abundance of various lymphocytes (e.g., NK and γδT cells) in severe patients, revealing that lymphopenia might be a prominent feature of severe disease. Further analyses indicated that significant activation of cell apoptosis pathways, including perforin/granzyme-, TNF-, FAS- and XAF1-induced apoptosis, as well as cell migration pathways might confer this reduction. The immune landscape in severe patients was characterized by widespread immune exhaustion in Th1, CD8+T and NK cells as well as high cytotoxic state in CD8+T and NK cells. We also discovered that myeloid cells in severe TB patients may involve in the immune paralysis. Systemic upregulation of S100A12 and TNFSF13B, mainly by monocytes in the peripheral blood, may contribute to the inflammatory cytokine storms in severe patients. Our data offered a rich resource for understanding of TB immunopathogenesis and designing effective therapeutic strategies for TB, especially for severe patients.


Assuntos
Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose , Humanos , Transcriptoma , Células Matadoras Naturais
4.
Front Public Health ; 11: 1039399, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778546

RESUMO

Background and objective: Retreatment pulmonary tuberculosis (PTB) still accounts for a large proportion of tuberculosis, and the treatment outcome is unfavorable. The recurrence of retreatment PTB based on long-term follow-up has not been well demonstrated. This study aimed to evaluate effect of a modified regimen on drug-sensitive retreated pulmonary tuberculosis. Methods: This multicenter cohort study was conducted in 29 hospitals from 23 regions of China from July 1, 2009, to December 31, 2020. Patients were divided into two treatment regimen groups including experimental group [modified regimen (4H-Rt2-E-Z-S(Lfx)/4H-Rt2-E)]and control group [standard regimen (2H-R-E-Z-S/6H-R-E or 3H-R-E-Z/6H-R-E)]. The patients enrolled were followed up of 56 months after successful treatment. We compared the treatment success rate, treatment failure rate, adverse reaction rate, and recurrence rate between two regimens. Multivariate Cox regression model was used to identify the potential risk factors for recurrence after successful treatment with proportional hazards assumptions tested for all variables. Results: A total of 381 patients with retreatment PTB were enrolled, including 244 (64.0%) in the experimental group and 137 (36.0%) in the control group. Overall, the treatment success rate was significant higher in the experimental group than control group (84.0 vs. 74.5%, P = 0.024); no difference was observed in adverse reactions between the two groups (25.8 vs. 21.2%, P > 0.05). A total of 307 patients completed the 56 months of follow-up, including 205 with the modified regimen and 102 with the standard regimen. Among these, 10 cases (3.3%) relapsed, including 3 in the experimental group and 7 in the control group (1.5% vs 6.9%, P = 0.035). Reduced risks of recurrence were observed in patients treated with the modified regimen compared with the standard regimen, and the adjusted hazard ratio was 0.19 (0.04-0.77). Conclusion: The modified retreatment regimen had more favorable treatment effects, including higher treatment success rate and lower recurrence rate in patients with retreated drug-sensitive PTB.


Assuntos
Antituberculosos , Tuberculose Pulmonar , Humanos , Antituberculosos/uso terapêutico , Estudos de Coortes , Resultado do Tratamento , Tuberculose Pulmonar/tratamento farmacológico , China
5.
Indian J Med Res ; 134: 356-61, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21985819

RESUMO

BACKGROUND & OBJECTIVES: The unique immunological functions of γδ T lymphocytes to contribute immunity against Mycobacterium tuberculosis attracted interest of researchers. However, little is known about the specificity of γδ Τ cell in tuberculosis patients and the lack of exact tuberculosis antigen recognized by γδ T cells limited its application. The analysis of complementary determinant region (CDR)3 sequence characteristic in γδ T cells of tuberculosis patients would contribute to understand the distribution specificity of γδ T cell. In present study, we investigated the diversity of the γ9/δ2 T cell immunorepertoire and analysed the specificity of the expressed CDR3 in pulmonary tuberculosis patients. METHODS: The total RNA in peripheral blood mononuclear cell of 50 pulmonary tuberculosis patients and 10 healthy controls was extracted. The polymerase chain reaction was used to specifically amplify the CDR3 region of γ9 and δ2 chain. The PCR products were ligated into the pGEM-T easy vector. The plasmid DNA was sequenced using the ABI3700 and the T7 primer. RESULTS: Our findings showed that predominant CDR3 sequence of δ2 chain in pulmonary tuberculosis patients was CACDTLVSTDKLIFGKG. The sequence specifically exists in almost all pulmonary tuberculosis patients. The conserved hydrophobic acid residue in 97 positions is present in the γδ T cell reactive to M. tuberculosis. The length of δ2 CDR3 in pulmonary tuberculosis patients has no relation with the disease progress. INTERPRETATION & CONCLUSIONS: Our results suggest that γδ T cells appear to use CDR3 sequence to recognise M. tuberculosis antigen. γδ T cells reactive to M. tuberculosis were diverse and polyclonal.


Assuntos
Regiões Determinantes de Complementaridade/metabolismo , Mycobacterium tuberculosis/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T/imunologia , Tuberculose Pulmonar/imunologia , Motivos de Aminoácidos/genética , Primers do DNA/genética , Feminino , Vetores Genéticos , Humanos , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Linfócitos T/metabolismo
6.
Zhonghua Jie He He Hu Xi Za Zhi ; 34(10): 762-5, 2011 Oct.
Artigo em Zh | MEDLINE | ID: mdl-22321711

RESUMO

OBJECTIVE: To compare the antimycobacterial activities of rifampicin (RFP) and rifabutin (RBT), and to evaluate the correlation between RBT resistance and genetic alterations in the rpoB gene. METHODS: The microplate-based alamar blue assay (MABA) method was performed to detect the antimycobacterial activities of RFP and RBT in 168 strains of Mycobacterium tuberculosis (M. tuberculosis). Meanwhile, we also analyzed the 81 bp core region of rpoB gene by DNA sequencing. The rate of gene mutations was analyzed by chi-square test. RESULTS: RBT was sensitive for all of the 66 RFP-sensitive strains with no mutations in 81 bp core region of rpoB gene. But of the 102 RFP-resistant strains, 76 strains were also resistant to RBT. Cross resistance between RFP and RBT was 74.5% (76/102). Alterations at codons 516, 526, 531 in the rpoB gene correlated with resistance to both RFP and RBT. While point mutations at codons 511 and 533 possibly influenced the susceptibility to RFP but not to RBT. The mutation rate (92.1%, 70/76) of rpoB gene of RBT-resistant strains was significantly higher than that (23.9%, 22/92) of RBT-sensitive strains (χ(2) = 78.12, P < 0.05). CONCLUSIONS: RBT was more active against M. tuberculosis as compared to RFP. The RFP-resistant strains with MIC ≤ 4 mg/L were still susceptible to RBT. Our results suggest that analysis of genetic alterations in the rpoB gene is useful for predicting RFP-resistance, and may have implications for evaluating RBT-resistance.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Mycobacterium tuberculosis/genética , Rifabutina/farmacologia , Rifampina/farmacologia , Análise Mutacional de DNA , RNA Polimerases Dirigidas por DNA , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Análise de Sequência de DNA
7.
Medicine (Baltimore) ; 99(44): e22258, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33126298

RESUMO

We aimed to investigate the effect of interval between food intake and drug administration at fasting condition on the plasma concentrations of first-line anti- tuberculosis (TB) drugs in Chinese population. Newly diagnosed TB patients administered the anti-TB drugs under fasting conditions orally, and then had prepared breakfast at 30 minutes and 120 min after dosing, respectively. Blood sampling was also performed 120  minutes after dosing for the detection of Cmax purpose. Overall, twenty-five participants were included in our analysis. The Cmaxs of 30  minutes interval and 120  minutes interval were 21.8 ±â€Š2.0 and 19.2 ±â€Š2.0 µg/mL for rifampin, 1.6 ±â€Š0.2 and 2.1 ±â€Š0.2 µg/mL for isoniazid (INH), 1.5 ±â€Š0.1and 1.5 ±â€Š0.2 µg/mL for ethambutol (EMB), and 49.2 ±â€Š3.7 and 41.5 ±â€Š3.9 µg/mL for pyrazinamide, respectively. Statistical analysis revealed that there was no statistical difference between 2 groups. Additionally, 88.0% and 72.0% of the 25 participants at 2-hour interval group had peak concentrations less than the lower limit of the reference range for INH and EMB, respectively. The Cmaxs of INH were 0.9 ±â€Š0.4 µg/ml for rapid acetylator, which was significantly lower than those of intermediate (1.4 ±â€Š1.0 µg/mL), and slow acetylator (2.5 ±â€Š1.0 µg/mL), respectively (P < .01). In conclusion, our data demonstrate that early food intake at 30 minutes after drug administration had no significant influence on the plasma concentrations. In addition, a high proportion of patients receiving first-line anti-TB regimen fail to achieve the expected plasma drug ranges of INH and EMB (P > .05).


Assuntos
Antituberculosos/sangue , Ingestão de Alimentos , Jejum/sangue , Fatores de Tempo , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/tratamento farmacológico , Administração Oral , Adulto , Antituberculosos/administração & dosagem , China , Esquema de Medicação , Etambutol/administração & dosagem , Etambutol/sangue , Feminino , Humanos , Isoniazida/administração & dosagem , Isoniazida/sangue , Masculino , Pirazinamida/administração & dosagem , Pirazinamida/sangue , Rifampina/administração & dosagem , Rifampina/sangue , Resultado do Tratamento
8.
Cytokine X ; 2(2): 100028, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33604556

RESUMO

Tuberculosis (TB) patient serum cytokine levels may be predictive of anti-tuberculosis treatment progress. Here, serum levels of cytokines TNF-α, IL-4, sIL-2R and IFN-γ were measured then correlated to clinical TB manifestations, bacterial burden, chest imaging findings and clinical course. Study subjects included 67 newly diagnosed pulmonary TB (PTB) patients with active disease admitted to Beijing Chest Hospital for anti-TB chemotherapeutic treatment. Blood was drawn at 0 months (pre-treatment), 1-2 months (at any time between 1 and 2 month) and after 6 months completion of treatment and serum TNF-α, IL-4, sIL-2R and IFN-γ levels were measured in duplicate using enzyme-linked immunosorbent assays (ELISAs). Correlation analysis was conducted to evaluate sensitivity and specificity of cytokine levels as predictors of disease activity and treatment progress. The results indicated that the pre-treatment serum TNF-α level of the smear-negative group was lower than that of the smear 1+ group, while serum TNF-α after 6 months completion of treatment and IFN-γ levels at 1-2 months and after 6 months completion of treatment were significantly lower, respectively, than at 0 months (before treatment) (P < 0.05). Using a cut-off value of 845 pg/ml, serum TNF-α level was predictive of treatment progress, with a sensitivity of 51%, specificity of 60% and AUC of 0.594 (P = 0.013). Meanwhile, using a cut-off value of 393 pg/ml, serum IFN-γ provided superior monitoring efficacy, with a sensitivity of 60%, specificity of 64% and AUC of 0.651 (P = 0.017). In conclusion, both serum TNF-α and IFN-γ levels might be useful biomarkers for monitoring treatment progress.

9.
Infect Drug Resist ; 12: 763-770, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31040707

RESUMO

BACKGROUND: Our aim was to assess whether the use of cycloserine (CS) would bring additional benefit for multidrug-resistant tuberculosis (MDR-TB) patients, and to estimate the incidence and associated risk factors of adverse drug reactions (ADRs) from CS. PATIENTS AND METHODS: In this study, we retrospectively reviewed the clinical outcomes and ADRs of MDR-TB patients treated with CS containing regimens between January 2012 and June 2015 in China. RESULTS: A total of 623 MDR-TB cases enrolled in this study received regimens containing CS. Of these cases, in 411 of the patients 374 (66.0%) were "cured" and 37 (5.9%) "complete treatment" by the end of the study. The elderly, patients with prolonged previous exposure to and history of anti-TB drugs, and pre-existing co-morbidity were more likely to be associated with adverse outcomes of MDR-TB patients (P<0.05). Hyperuricemia (22.8%, 142/623) was the most frequently observed ADR among these cases, while the most noted ADRs associated with the administration of CS was psychiatric symptoms, accounting for 4.3% (27/623) of study population. Nineteen (70.4%) out of 27 cases with psychiatric symptoms occurred before the 6-month timepoint, and were notably, the highest proportion of serious adverse, 29.6% (8/27) of which were noted after discontinuation of CS. CONCLUSION: Our study demonstrates that a CS-containing regimen achieved a highly successful outcome in the treatment of MDR-TB and promising tolerance in Chinese population. The potential emergence of serious psychiatric symptoms highlights that patients need to be closely monitored for these conditions during treatment that includes CS.

10.
Sci Rep ; 6: 36299, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27808247

RESUMO

The clinical relevance of non-tuberculous mycobacteria (NTM) has been reported to be different dramatically by species or by regions, however, no such evaluation has been performed in China.A retrospective study was performed in Beijing Chest Hospital. All the NTM strains isolated from respiratory specimens in the past 5 years, and patients' clinical records (symptoms and radiographic information etc.) were investigated. The clinical relevance was evaluated according to the criteria recommended by the American Thoracic society. Totally 232 NTM strains were recruited, among them, M. intracellulare was the dominant species (40.5%), followed by M. abscessus (28.4%). 109 patients, with 185 total isolates, had full clinical records available for review. 84.4% (38/45), 85.7% (24/28%) and 63.6% (7/11) of patients with isolation of M. intracellulare, M. abscessus and M. kansasii, respectively, were categorized as definite NTM disease. Whereas all the 10 patients with isolation of M. gordonae were defined as unlikely NTM disease. The majority of NTMs isolates yielded from respiratory specimens in Beijing Chest Hospital were clinically significant, and M. intracellulare and M. abscessus was the dominated species of NTM lung disease. NTM lung infections demonstrated some specific chest radiograph characteristics.


Assuntos
Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/fisiologia , Sistema Respiratório/microbiologia , Centros de Atenção Terciária , Adulto , Idoso , Povo Asiático , Pequim , Feminino , Humanos , Pneumopatias/etnologia , Pneumopatias/microbiologia , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/etnologia , Micobactérias não Tuberculosas/classificação , Micobactérias não Tuberculosas/genética , Estudos Retrospectivos , Especificidade da Espécie , Tuberculose/diagnóstico , Tuberculose/etnologia , Tuberculose/terapia
11.
Zhonghua Jie He He Hu Xi Za Zhi ; 28(8): 545-9, 2005 Aug.
Artigo em Zh | MEDLINE | ID: mdl-16207403

RESUMO

OBJECTIVE: To investigate the in-vitro interferon-gamma (IFN-gamma) release assay based on three different Mycobacterium tuberculosis antigens in the diagnosis of tuberculosis and Mycobacterium tuberculosis infections. METHODS: The peripheral blood mononuclear cells (PBMC) were collected from the patients with tuberculosis (tuberculosis group, n = 57), patients with lung cancer (lung cancer group, n = 29), and healthy controls (healthy control group 2, n = 27). The PBMCs were co-cultured for 5 days with different antigens: purified protein derivatives (PPD) of tuberculin, early secretary antigenic target 6,000 protein (ESAT6) and 38,000 antigen. The protein levels of IFN-gamma were detected by ELISA, and the results were compared to those with the tuberculin skin test (TST). RESULTS: (1) For healthy controls, the TST was positively related to the history of BCG vaccination and the closeness of contact with sputum-positive tuberculosis patients (P = 0.047, P = 0.041 respectively). The ESAT6 based IFN-gamma release assay was only significantly related to the closeness of contact with sputum-positive tuberculosis patients (P = 0.005), but not to the history of BCG vaccination. (2) There was no significant difference of the TST results among the three groups (P > 0.05). (3) The receiver operating characteristic (ROC) curve analysis indicated that the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the IFN-gamma release assay based on 38,000 antigen were 64.9%, 89.3%, 77.0%, 86.0%, and 71.0% respectively for the diagnosis of tuberculosis. CONCLUSIONS: IFN-gamma release assay based on ESAT6 appears to be better than TST in the diagnosis of infection of Mycobacterium tuberculosis, while IFN-gamma release assay based on 38,000 may be helpful for the diagnosis of tuberculosis.


Assuntos
Interferon gama/sangue , Leucócitos Mononucleares/metabolismo , Tuberculose/diagnóstico , Adulto , Idoso , Antígenos de Bactérias/imunologia , Proteínas de Bactérias , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis , Valor Preditivo dos Testes , Curva ROC , Sensibilidade e Especificidade , Teste Tuberculínico , Tuberculose/sangue , Tuberculose/imunologia
12.
Zhonghua Jie He He Hu Xi Za Zhi ; 27(12): 815-9, 2004 Dec.
Artigo em Zh | MEDLINE | ID: mdl-15730780

RESUMO

OBJECTIVE: To rapidly identify drug-resistant Mycobacterium tuberculosis using phenotypic and genotypic methods and to evaluate the clinical significance of rapid phenotypic susceptibility test by phage amplified biologically assay (PhaB). METHODS: PhaB, DNA sequencing and polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) were performed on the 91 rifampicin (RFP)-resistant strains (including 82 multi-drug resistant Mycobacterium tuberculosis strains), 42 RFP-susceptible strains, 75 ofloxacin (OFLX)-resistant strains and 40 OFLX-susceptible strains at the same time. RESULTS: The results obtained using PhaB assay, DNA sequencing and PCR-SSCP were compared with the absolute concentration method. For RFP susceptibility, the accordance, sensitivity and specificity of PhaB were 93%, 92% and 95% respectively; the accordance, sensitivity and specificity of DNA sequencing were 93%, 90% and 100% respectively; those of PCR-SSCP were 90%, 86% and 100% respectively. For OFLX susceptibility, the accordance, sensitivity and specificity of PhaB assay were 95%, 95% and 95%; those of DNA sequencing were 80%, 71% and 98% respectively; those of PCR-SSCP were 75%, 63% and 98% respectively. CONCLUSIONS: PhaB assay is a low-cost, rapid, and sensitive method and shows high accordance with absolute concentration technology. It can give drug susceptibility test results within 48 - 96 h, and is a promising technology in clinical laboratory.


Assuntos
Farmacorresistência Bacteriana/genética , Micobacteriófagos , Mycobacterium tuberculosis/efeitos dos fármacos , Rifampina/farmacologia , Antibióticos Antituberculose/farmacologia , Sequência de Bases , Contagem de Colônia Microbiana , Testes de Sensibilidade Microbiana/métodos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Polimorfismo Conformacional de Fita Simples , Sensibilidade e Especificidade , Análise de Sequência de DNA
13.
Clin Vaccine Immunol ; 20(4): 530-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23389928

RESUMO

The immune protection initiated by γδ T cells plays an important role in mycobacterial infection. The γδ T cells activated by Mycobacterium tuberculosis-derived nonpeptidic, phosphorylated biometabolites (phosphoantigens) provide only partial immune protection against mycobacterium, while evidence has suggested that protein antigen-activated γδ T cells elicit effective protective immune responses. To date, only a few distinct mycobacterial protein antigens have been identified. In the present study, we screened protein antigens recognized by γδ T cells using cells transfected with the predominant pulmonary tuberculosis γδ T cell receptor (TCR) CDR3 fragment. We identified two peptides, TP1 and TP2, which not only bind to the pulmonary tuberculosis predominant γδ TCR but also effectively activate γδ T cells isolated from pulmonary tuberculosis patients. Moreover, 1-deoxy-d-xylulose 5-phosphate synthase 2 (DXS2), the TP1-matched mycobacterial protein, was confirmed as a ligand for the γδ TCR and was found to activate γδ T cells from pulmonary tuberculosis patients. The extracellular region (extracellular peptide [EP]) of Rv2272, a TP2-matched mycobacterial transmembrane protein, was also shown to activate γδ T cells from pulmonary tuberculosis patients. Both DXS2- and EP-expanded γδ T cells from pulmonary tuberculosis patients could secrete gamma interferon (IFN-γ) and monocyte chemoattractant protein 1 (MCP-1), which play important roles in mediating cytotoxicity against mycobacterium and stimulating monocyte chemotaxis toward the site of infection. In conclusion, our study identified novel mycobacterial protein antigens recognized by γδ TCR cells that could be candidates for the development of vaccines or adjuvants against mycobacterium infection.


Assuntos
Antígenos de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Adulto , Antígenos de Bactérias/metabolismo , Quimiocina CCL2/metabolismo , Feminino , Humanos , Interferon gama/metabolismo , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia
14.
PLoS One ; 6(4): e18809, 2011 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-21526117

RESUMO

BACKGROUND: Phosphoantigen was originally identified as the main γδ TCR-recognized antigen that could activate γδ T cells to promote immune protection against mycobacterial infection. However, new evidence shows that the γδ T cells activated by phosphoantigen can only provide partial immune protection against mycobacterial infection. In contrast, whole lysates of Mycobacterium could activate immune protection more potently, implying that other γδ TCR-recognized antigens that elicit protective immune responses. To date, only a few distinct mycobacterial antigens recognized by the γδ TCR have been characterized. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we established a new approach to screen epitopes or protein antigens recognized by the γδ TCR using Bacillus Calmette-Guérin- (BCG-) specific γ TCR transfected cells as probes to pan a 12-mer random-peptide phage-displayed library. Through binding assays and functional analysis, we identified a peptide (BP3) that not only binds to the BCG-specific γδ TCR but also effectively activates γδ T cells isolated from human subjects inoculated with BCG. Importantly, the γδ T cells activated by peptide BP3 had a cytotoxic effect on THP-1 cells infected with BCG. Moreover, the oxidative stress response regulatory protein (OXYS), a BCG protein that matches perfectly with peptide BP3 according to bioinformatics analysis, was confirmed as a ligand for the γδ TCR and was found to activate γδ T cells from human subjects inoculated with BCG. CONCLUSIONS/SIGNIFICANCE: In conclusion, our study provides a novel strategy to identify epitopes or protein antigens for the γδ TCR, and provides a potential means to screen mycobacterial vaccines or candidates for adjuvant.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Mycobacterium bovis/imunologia , Biblioteca de Peptídeos , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Adolescente , Adulto , Sequência de Aminoácidos , Antígenos de Bactérias/química , Proteínas de Bactérias/química , Epitopos/química , Epitopos/imunologia , Feminino , Humanos , Ativação Linfocitária/imunologia , Masculino , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/imunologia , Ligação Proteica , Reprodutibilidade dos Testes , Homologia de Sequência de Aminoácidos , Linfócitos T/imunologia , Transfecção , Vacinação , Adulto Jovem
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