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Preparation and Use of HIV-1 Infected Primary CD4+ T-Cells as Target Cells in Natural Killer Cell Cytotoxic Assays
Published on: March 14, 2011
Circulating immune complexes from HIV-1+ patients induces apoptosis on normal lymphocytes
E Aceituno1, S Castañón, C Jiménez
1Department of Immunology, Fundación Jiménez Díaz, Madrid, Spain.
Immunology
|March 5, 1998
Summary
Immune complexes in human immunodeficiency virus-1 (HIV-1) patients can trigger apoptosis, programmed cell death, in CD4+ lymphocytes. This finding suggests a mechanism by which HIV-1 infection may deplete crucial immune cells, particularly in asymptomatic individuals.
Area of Science:
- Immunology
- Virology
- Cell Biology
Background:
- Immune complexes (ICs) are implicated in various autoimmune and infectious diseases.
- Human immunodeficiency virus-1 (HIV-1) infection leads to progressive depletion of CD4+ T lymphocytes, a hallmark of AIDS.
- The precise mechanisms driving CD4+ T cell loss in HIV-1 infection are not fully understood.
Purpose of the Study:
- To investigate the potential of immune complexes from HIV-1-positive patients to induce apoptosis in normal lymphocytes.
- To identify the specific lymphocyte subset targeted by these immune complexes.
- To explore the role of Fas antigen expression in the observed apoptotic process.
Main Methods:
- Isolation of immune complexes (CICs) from the sera of HIV-1-positive patients.
- Induction of apoptosis in phytohemagglutinin (PHA)-activated lymphocytes.
- Detection of DNA degradation using propidium iodide staining.
- Assessment of CD4+ lymphocyte targeting via double binding assays with anti-CD4 antibodies.
- Evaluation of Fas antigen expression on apoptotic cells.
Main Results:
- Immune complexes from 49 out of 67 HIV-1-positive patients induced apoptosis in PHA-activated lymphocytes.
- The apoptosis-inducing activity was specifically directed against CD4+ lymphocytes.
- Fas antigen expression preceded the apoptotic events.
- The apoptosis inducers were predominantly found in asymptomatic HIV-infected patients.
Conclusions:
- Immune complexes in HIV-1-positive individuals can directly induce apoptosis in CD4+ lymphocytes.
- This mechanism may contribute to the depletion of CD4+ T cells during HIV-1 infection, even in the asymptomatic stage.
- Targeting of CD4+ lymphocytes by HIV-1 immune complexes highlights a potential pathway for immune system dysfunction.
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