Performance of a simple flow cytometric assay in diagnosing active tuberculosis.

A flow cytometric assay measuring Mycobacterium tuberculosis-specific CD4 T-cell responses using co-expression of CD25/CD134 (OX40 assay) was explored as a diagnostic tool for active tuberculosis (TB) in a Thai population with and without HIV infection. Peripheral blood mononuclear cells (PBMC) obtained from 133 participants at TB diagnosis were cryopreserved. Seventy-six participants had a clinical diagnosis of TB which were confirmed by a positive culture.

Utility of urine lipoarabinomannan (LAM) in diagnosing tuberculosis and predicting mortality with and without HIV: prospective TB cohort from the Thailand Big City TB Research Network.

Objectives: To evaluate the applicability and accuracy of the urine lipoarabinomannan (LAM) test in tuberculosis (TB)/HIV co-infected patients and HIV-negative patients with disseminated TB.

Methods: Frozen urine samples obtained at baseline from patients in the TB research cohort with proven culture-positive TB were selected for blinded urine LAM testing. One hundred and nine patients were categorized into four groups: (1) HIV-positive patients with TB; (2) HIV-negative patients with disseminated TB; (3) HIV-negative immunocompromised patients with TB; and (4) patients with diseases other than TB.

Incomplete restoration of Mycobacterium tuberculosis-specific-CD4 T cell responses despite antiretroviral therapy.

Objectives: Despite antiretroviral therapy (ART), HIV-infected persons have increased risk of active tuberculosis (TB). PPD and combined ESAT-6 and CFP-10-specific-CD4 (EC-Sp-CD4) responses were examined over 96 weeks.

Methods: HIV-infected, ART-naive Thai adults with CD4 T cell count ≤350 cells/μL starting ART were assessed at baseline, wk4, 8, 12, 24, 48 and 96.

Restoration of CMV-specific-CD4 T cells with ART occurs early and is greater in those with more advanced immunodeficiency.

Objectives: Restoration of Cytomegalovirus-specific-CD4 T cell (CMV-Sp-CD4) responses partly accounts for the reduction of CMV-disease with antiretroviral-therapy (ART), but CMV-Sp-CD4 may also drive immune activation and immunosenescence. This study characterized the dynamics of CMV-Sp-CD4 after ART initiation and explored associations with CD4 T cell recovery as well as frequency of naïve CD4 T cells at week 96.

Methods: Fifty HIV-infected, ART-naïve Thai adults with CD4 T cell count ≤ 350 cells/µL and starting ART were evaluated over 96 weeks (ClinicalTrials.

Association of APOBEC3G genotypes and CD4 decline in Thai and Cambodian HIV-infected children with moderate immune deficiency.

Introduction: Human APOBEC3G is a host defense factor that potently inhibits HIV replication. We hypothesize that HIV-infected children with a genetic variant of APOBEC3G will have a more rapid disease progression.

Methods: Antiretroviral therapy (ART)-naïve children, aged 1-12 years old with CD4 15-24% and without severe HIV-related symptoms were enrolled.

A novel assay detecting recall response to Mycobacterium tuberculosis: Comparison with existing assays.

A strategy to reduce the burden of active TB is isoniazid preventive therapy for latent TB infection (LTBI). However, current assays used to diagnose LTBI all have limitations. In these proof of concept studies, we compared the agreement of a novel flow cytometry assay detecting CD25/CD134 co-expression with QuantiFERON-TB Gold In-Tube (QFN-GIT) and Tuberculin skin test (TST) in the detection of recall immune response to TB.