Objective To evaluate the application of enzyme-linked immunospot assay (T SPOT) in diagnosis of Mycobacterium tuberculosis (MTB) infection for AIDS patients. Methods The rapid T SPOT assay was employed to detect ESAT-6 and CFP-10 specific T cells in blood samples from 35 AIDS patients with active tuberculosis. The results were compared with those of PPD skin test. Results The positive-MTB rate with T SPOT assay in all patients (n = 35 ) was 65.71%, that in patients with CD4 < 200/μ (n = 21) was 66.67%, in patients with CD4 > 200/μl (n = 10) was 60.0% , in patients with anti-tuberculosis treatment < 2 months ( n = 15 ) was 83.33% and in patients with treatment > 2 months ( n = 6 ) was 25.00%. The positive rates of PPD skin test were 24.24%, 25.00%, 33.33%, 9.09% and 25.00% in these groups, respectively. The positive rates of T SPOT assay were significantly higher than those of PPD skin test in all patients, in those with CD4 < 200/μl and with anti-tuberculosis treatment < 2 months ( P < 0.05 ). Conclusion T SPOT assay was more sensitive than conventional PPD skin test, and can be applied in the diagnosis of MTB infections for AIDS patients.

Objective To investigate the incidence of Mycobacterium tuberculosis (TB) infection among human immunodeficiency virus (HIV)-infected individuals in Shanghai and Yunnan Province and to analyze the risk factors of TB infection.Methods Seventy HIV-infected individuals from Yunnan Province and 67 from Shanghai were enrolled.T-SPOT.TB was employed to detect TB-specific T cells in the peripheral blood mononuclear cells (PBMC).CD4+ and CD8+ T cells in PBMC from the enrolled subjects were detected by flow cytometry.Data were analyzed using Mann-Whitney test,Fisher's exact test and Logistic regression.Results The incidence of latent tuberculosis (LTB) infection among HIV-infected individuals in Yunnan Province was 64.3 ％ (45/70),which was much higher than Shanghai (20.8％ [14/ 67]).The median CD4+ T cell count of HIV-infected individuals with LTB infection in Yunnan Province was 509/μL,while that in Shanghai was 324/μL,which was significant different (U=148,P=0.003).The median CD4+ T cell count in HIV single infected individuals from Yunnan Province was 418/μL,which was not significantly different from that of H IV + LTB individuals from that area (U =378,P =0.120).Moreover,the median CD8+ T cell counts of HIV-infected individuals with latent tuberculosis infection in Yunnan Province and Shanghai were 409/μL and 781/μL,respectively (U=109,P＜0.01).Conclusions The incidence of LTB infection among HIV-infected individuals in Yunnan Province is significantly higher than Shanghai.CD4+ and CD8+ T cell counts are correlated with TB infection among HIV-infected individuals.

Objective To investigate the molecular epidemiology of human immunodefieiency viruses (HIV)-1 infected individuals in Honghe district,Yunnan Province and provide the evidence of molecular biology features of HIV-1 infection.Methods HIV-1 pol gene was amplified by reverse transcription-polymerase chain reaction (RT-PCR).Then sequencing and phylogenetic tree analysis were employed tO determine HIV-I subgenotype.The sequence alignment was performed in the database of international drug resistance tO identify resistance-associated mutations.Results The samples from 60 HIV-1 infected individuals were investigated:39 were male,21 were female,with average age 35.5 years old.Thirty-four cases were infected with HIV-I through intravenous drug abuse,12 by sexual contacts,2 were contaminated blood/blood products transfusion and 12 with unknown transmission routes.Phylogenetic analysis revealed that 53 cases (88.3%) were subtype 08-BC,6 (10.0%) were subtype 07-BC and 1 (1.7%) was subtype 01_AE.The total rate of drug resistance associated mutations was 33.3%.The major mutations in protease (PR) and reverse transcriptase (RT) regions accounted for 5.0% and 3 1.7%,respectively.The major mutations in PR region were I541M,V82VFIL,M46MI,which were found in 1 case,respectively.The mutations in RT region were as follows:4 cases were T69D,6 were A62V,1 was D67DE,1 was E44D,3 were V179D,1 was V179E.1 was K238KN,1 was L234T+P236S and 1 was V106E.Conclusions The major transmission route of HIV-I infection in Honghe district,Yunnan Province is through drug injection.The major HIV-1 subtype of HIV-infeeted individuals is 08_BC.PR inhibitor and RT inhibitor drug resistance associated mutations in HlV-1 gene have already existed.

Objective To evaluate Mycobacterium tuberculosis (M. tuberculosis)-specific cellular immunity in individuals with latent or active tuberculosis and human immunodeficiency virus (HIV) coinfection. Methods One hundred HIV-infected individuals in Yunnan Province were enrolled. The enzyme-linked immunospot (ELISPOT) assay using early secreted antigenic target (ESAT)-6 and culture filtrate protein (CFP)-10 was employed to detect M. tuberculosis-specific T cells in the peripheral blood. The absolute number of CD3+ CD4+and CD3+ CD8+ T cells in the peripheral blood from the enrolled subjects were determined by flow cytometry. Data were analyzed using nonparametric Mann-Whitney test. Results The prevalence of latent tuberculosis co-infection in HIV-infected individuals without any clinical evidence of active tuberculosis was 67.6%. The absolute numbers of CD3+ CD4+ (532 × 106/L) and CD3+ CD8+ (473 × 106×/L) T cell in HIV-infected individuals with latent tuberculosis co-infection were similar to those of only HIV-infeeted individuals (406 ×106×/L and 504 × 106/L). While those in HIV-infected individuals with active tuberculosis co-infection were 189 × 106/L and 293 × 106/L, respectively, which were both significantly lower than those in other two groups (U=168. 0,U=163. 0,U= 374. 0,U=147. 0, all P<0. 01). Furthermore, ESAT-6 (31/106 cells) and CFP-10 (82/106 cells) specific spot-forming cells in HIV-infected individuals with active tuberculosis co-infection were significantly less than those in HIV-infected individuals with latent tuberculosis co-infection (92 × 106 cells and 109 × 106 cells, U= 507. 0,U= 529. 5, both P<0. 01). Conclusions The prevalence of latent tuberculosis in HIV-positive individuals without any clinical evidence of active tuberculosis is high in China. Both overall cellular immunity and M. tuberculosis-specific immune response in HIV-positive individuals with active tuberculosis co-infection are severely impaired.