Victorino RM, Sousa AE; Keystone Symposia on Molecular and Cellular Biology: 1998 HIV Pathogenesis and Treatment.
Keyst Symp Mol Cell Biol Keyst Symp Mol Cell Biol. 1998 Mar 13-19; 104 (abstract no. 4093).
Faculty of Medicine of Lisbon-Cellular Immunology Unit (CEBIP), Lisbon, Portugal.
In this study we investigated at single cell level by flow cytometry the potential of T cell cytokine production in asymptomatic HIV1 infected subjects with more than 200 CD4 counts and possible correlation with T helper cell depletion and viral load. Mitogen stimulated peripheral blood mononuclear cells from 32 HIV1+ patients and 16 healthy subjects were intracytoplasmicaly stained for IL2, IFNgamma, IL4 or IL10, and the frequency of cytokine producing cells was assessed in total T cells, CD4, CD8, CD28 and CD45RO subsets as well as in CD69+CD3+ gated lymphocytes. HIV1+ patients, irrespectively of their degree of CD4 depletion, exhibited a major increase in IFNgamma+ CD8 T cells, largely due to CD28- cells, as well as a decrease in the capacity of CD8 T cells to produce IL2. Patients with more than 500 CD4 counts showed a diminished frequency of IL4 expression in CD4 T cells and a negative correlation was found between this parameter and the ex vivo CD4 counts in the 32 patients. Analysis of patients stratified according to viral load revealed a significantly higher proportion of IL2 producing CD4 cells in the group with less than 5000 RNA copies/ml. In summary, using single cell analysis and an APC independent stimulus, we have not been able to find major cytokine imbalances in the CD4 subset, suggesting that the well described T helper defects are not due to intrinsic alterations in the potential of CD4 T cells to produce cytokines. On the other hand, the major disturbances in the CD8 T lymphocytes agrees with the marked activation and possible replicative senescence of CD8 T cells and emphasises the role of this subset in HIV immunopathogenesis.
Publication Types:
Keywords:
- Antigens, CD
- Antigens, CD28
- Antigens, CD3
- Antigens, CD4
- Antigens, CD45
- Antigens, CD8
- CD4 Lymphocyte Count
- CD4-Positive T-Lymphocytes
- CD69 antigen
- CD8-Positive T-Lymphocytes
- Communicable Diseases
- Cytokines
- HIV Infections
- HIV Seropositivity
- HIV-1
- Humans
- Interleukin-2
- Interleukin-4
- Lymphokines
- T-Lymphocyte Subsets
- T-Lymphocytes
- T-Lymphocytes, Helper-Inducer
- Viral Load
- immunology
Other ID:
UI: 102236944
From Meeting Abstracts