34 research outputs found
Changing Burden of HIV/AIDS to Clinical Settings in Northern Thailand over 15 Years
No full textWe conducted a hospital-based descriptive study to describe the changing pattern of patient numbers, characteristics, and mortality rates among human immunodeficiency virus (HIV)-infected patients in northern Thailand over 15 years. The survival status on October 31, 2010 of all HIV-infected adults who attended an HIV center in a government hospital between 1995 and 2010 was ascertained. In total, 3,706 patients were registered, 2,118 (57.2%) of which were male. The survival status of 3,439 patients (92.9%) was available. In addition, 1,543 deaths were identified out of 12,858 person-year-observations (PYO) resulting in a mortality rate of 12.4 deaths/100 PYO (95% confidence interval [CI], 11.3-13.0). An initial decline in mortality rates was observed prior to 1999, probably because of an increase in the proportion of less symptomatic patients. After the introduction of the national highly active antiretroviral therapy (HAART) program, a profound decline in mortality rates was observed, reaching 2.0 deaths/100 PYO (95% CI, 1.4-2.9) in 2010. Simultaneously, the number of patients on follow-up increased by nearly fourfold. Although HAART has drastically improved the survival of HIV-infected patients, the number of patients receiving therapy at this HIV clinic has substantially increased. While referral of HIV patients to general physicians' care should be urged, we cannot overemphasize the importance of preventing new HIV infections
Survival Benefit from Non–Highly Active Antiretroviral Therapy in a Resource-Constrained Setting
No full textThe effect of HLA polymorphisms on the recognition of Gag epitopes in HIV-1 CRF01_AE infection.
No full textINTRODUCTION: The design of a globally effective vaccine rests on the identification of epitopes capable of eliciting effective cytotoxic T lymphocyte (CTL) responses across multiple HIV clades in different populations. This study aims to discern the effect of HLA polymorphisms and the cross-clade reactivity or clade-specificity of epitopes in Thailand where HIV-1 CRF01_AE is circulating. MATERIALS AND METHODS: 14 peptides based on consensus HIV-1 CRF01_AE amino acid sequences were designed for use in IFN-γ ELISpot assays and (51)Cr release assays among 66 HIV-1 CRF01_AE-infected Thai patients. For ELISpot responders carrying HLA alleles currently unknown to restrict CRF01_AE epitopes, in silico epitope-HLA prediction was performed. RESULTS: 29/66 (43.9%) patients recognized at least one peptide. In total 79 responses were seen against all 14 peptides. 28/79 (35.4%) of the responses were in patients with HLA alleles previously reported to restrict CRF01_AE epitopes, 24/79 (30.4%) responses were in individuals with HLA alleles previously reported to restrict epitopes of HIV clades other than CRF01_AE, and the remaining 27/79 (34.2%) responses were not associated with HLA alleles previously known to restrict HIV epitopes. In silico epitope prediction detected 19 novel, epitope-HLA combinations, and 11/19 (57.9%) were associated with HLA-C alleles. We further confirmed a novel HLA restriction of a previously identified HIV-1 Gag epitope [p24(122-130): PPIPVGDIY (PY9)] by HLA-B*40:01 with a standard (51)Cr release assay. DISCUSSION: CTL recognition sites in HIV-1 Gag were similar among different clades but the HLA restriction differed in Thai patients. This disparity in HLA restriction along different populations illustrated the importance of clade- and population-specific HLA analysis prior to CTL vaccine design
Unique CRF01_AE Gag CTL epitopes associated with lower HIV-viral load and delayed disease progression in a cohort of HIV-infected Thais.
No full textCytotoxic T Lymphocytes (CTLs) play a central role in controlling HIV-replication. Although numerous CTL epitopes have been described, most are in subtype B or C infection. Little is known about CTL responses in CRF01_AE infection. Gag CTL responses were investigated in a cohort of 137 treatment-naïve HIV-1 infected Thai patients with high CD4+ T cell counts, using gIFN Enzyme-Linked Immunospot (ELISpot) assays with 15-mer overlapping peptides (OLPs) derived from locally dominant CRF01_AE Gag sequences. 44 OLPs were recognized in 112 (81.8%) individuals. Both the breadth and magnitude of the CTL response, particularly against the p24 region, positively correlated with CD4+ T cell count and inversely correlated with HIV viral load. The breadth of OLP response was also associated with slower progression to antiretroviral therapy initiation. Statistical analysis and single peptide ELISpot assay identified at least 17 significant associations between reactive OLP and HLA in 12 OLP regions; 6 OLP-HLA associations (35.3%) were not compatible with previously reported CTL epitopes, suggesting that these contained new CTL Gag epitopes. A substantial proportion of CTL epitopes in CRF01_AE infection differ from subtype B or C. However, the pattern of protective CTL responses is similar; Gag CTL responses, particularly against p24, control viral replication and slow clinical progression
Impact of the National Access to Antiretroviral Program on the incidence of opportunistic infections in Thailand
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Unique CRF01_AE Gag CTL epitopes associated with lower HIV-viral load and delayed disease progression in a cohort of HIV-infected Thais.
No full textThe effect of KIR2D–HLA-C receptor–ligand interactions on clinical outcome in a HIV-1 CRF01_AE-infected Thai population
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Cytotoxicity assay with T cells Demonstration of a novel epitope-HLA association by <sup>51</sup>Cr release assay.
No full text<p>Specific lysis of Gag peptide p24<sub>122–130</sub> PPIPVGDIY (PY9) pulsed allogeneic target cells by effector CTLs from a HLA-B*40:01+ donor was assessed in a chromium release assay. The <i>Y</i> axis shows percentage specific lysis at an E∶T ratio of 20∶1 with the lysis (%) of unpulsed target cells subtracted. Effector cells were derived from patient 1509. HLA-B*40:01 matched cells pulsed with PY9 were also recognized by patient 326 (data not shown). HLA alleles shared by target cells and effector cells are shown; control indicates HLA-unmatched cells.</p
