Arroz M, Gaiao G, Pinto L, Costa L, Ordway D, Camacho R, Vera J, Ventura F; International Conference on AIDS.

Int Conf AIDS. 2000 Jul 9-14; 13: abstract no. MoPeA2115.

M. Arroz, Hospital Egas Moniz, Rua Da Junqueira, 126, 1349-019, Lisbon, Portugal, Tel.: +351 21 365 03 18, Fax: +351 21 362 49 96, E-mail: mjarroz@mail.telepac.pt

Background: Elevated CD38 antigen expression on CD8+ T cells is a marker of chronic immune activation in the pathogenesis of HIV disease. The aim of this study was to assess the median CD38 AB/C values for a control group of 13 HIV negative individuals and 55 HIV positive patients and to establish a correlation with CD4 absolute counts, CD4:CD8 ratios, viral loads and HAART therapy. Methods: CD38 staining results in a heterogeneous staining pattern because this antigen has a smeared antigen expression; we implemented a new methodology to quantitate CD38 CD38 antibodies bound per cell (AB/C) by flow cytometry. This system uses beads with 4 known and verified levels of fluorescence, a CD38 monoclonal antibody 1:1 conjugate and optimised analysis software. The CD4 absolute counts were also determined by 4 color flow cytometry in eytrocyte-lysed whole blood; viral loads were obtained by bDNA. Results: Individuals seropositive for HIV and on HAART were grouped based on CD4 T cell counts (CD4>500, CD4>200ndash;500, CD4>200). These groups showed a significant step-wise decrease of CD4/CD8 ratio which coincided with CD4 T cell counts and although less pronounced, viral loads. In comparison to healthy controls, HIV seropositive individuals (CD4>200ndash;500, CD4>200) had statically significant (p = .05) elevated levels of CD38 expression and (p = .08) in those individuals with CD4>500. Increased CD4/CD8 ratios was directly related to a better clinical profile and less CD38 expression. Conclusions: In comparison of the clinical profiles of HIV seropositive individuals it was evident that individuals on HAART showed higher expression of CD38 when CD4/CD8 ratios decreased and viral loads increased. Individuals not on HAART showed significantly increased levels of CD38 in comparison to the treated groups, which suggests the use of CD38 as a potential marker of nonadhearance to therapy.

Publication Types:

• Meeting Abstracts

Keywords:

• ADP-ribosyl Cyclase
• AIDS Vaccines
• Acquired Immunodeficiency Syndrome
• Antigens, CD
• Antigens, CD4
• Antigens, CD8
• Antiretroviral Therapy, Highly Active
• CD4 Lymphocyte Count
• CD4-Positive T-Lymphocytes
• CD8-Positive T-Lymphocytes
• Cell Adhesion Molecules
• HIV Infections
• HIV Seropositivity
• Humans
• T-Lymphocyte Subsets
• T-Lymphocytes
• Viral Load
• immunology

Other ID:

• GWAIDS0000173

UI: 102237662

From Meeting Abstracts