CD4+ T cell-mediated presentation of non-infectious HIV-1 virion antigens to HIV-specific CD8+ T cells / 中华医学杂志(英文版)
Chinese Medical Journal
;
(24): 1629-1638, 2006.
Article
in English
| WPRIM
| ID: wpr-335556
ABSTRACT
<p><b>BACKGROUND</b>The mechanism of chronic immune activation and impairment of HIV-specific immune responses during chronic infection is not fully understood. However, it is known that high immune activation leads to more rapid progression to AIDS. We hypothesize that CD4(+) T cell-mediated viral antigen presentation contributes to this pathologic immune activation in HIV-infected individuals.</p><p><b>METHODS</b>HIV-specific T cells, responding to noninfectious HIV-1 virions as antigen, were measured by flow cytometric assays. These experimental conditions reflect the in vivo condition where noninfectious HIV-1 represents more than 99% of the antigens.</p><p><b>RESULTS</b>CD4(+) T cells purified from HIV-infected individuals were capable of cross presenting exogenous noninfectious HIV-1 virions to HIV-1-specific CD8(+) T cells. Cross presentation required the entry of HIV-1 to CD4(+) T cells and antigen translocation from endoplasmic reticulum to the Golgi complex. Blocking CD4(+) mediated activation of HIV-specific CD8(+) T cells and redirecting the viral antigens to antigen presenting cells improved HIV-specific T cell responses.</p><p><b>CONCLUSIONS</b>One possible cause of chronic immune activation and impairment of HIV-1 specific T cell responses is represented by HIV-1 harboring CD4(+) T cells cross presenting HIV-1 antigen to activate CD8(+) T cells. This new mechanism provides the first evidence that cross presentation of noninfectious HIV-1 virions play a role in the immunopathogenesis of HIV-1 infection.</p>
Full text:
Available
Index:
WPRIM (Western Pacific)
Main subject:
Virion
/
Virology
/
Lymphocyte Activation
/
CD4-Positive T-Lymphocytes
/
HIV-1
/
Antigen Presentation
/
CD8-Positive T-Lymphocytes
/
Allergy and Immunology
Limits:
Adult
/
Humans
/
Male
Language:
English
Journal:
Chinese Medical Journal
Year:
2006
Type:
Article
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