Article

Normalization of B cell counts and subpopulations after antiretroviral therapy in chronic HIV disease.

Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.
The Journal of Infectious Diseases (Impact Factor: 5.78). 03/2008; 197(4):572-9. DOI: 10.1086/526789
Source: PubMed

ABSTRACT Untreated human immunodeficiency virus (HIV) disease leads to abnormalities in all major lymphocyte populations, including CD4(+) T cells, CD8(+) T cells, and B cells. However, little is known regarding the effect of antiretroviral therapy (ART)-induced decrease in HIV viremia on B cell numbers and subpopulations.
We conducted a longitudinal study to evaluate changes in B cell numbers and subpopulations that occur during the course of 12 months of effective ART in a group of individuals with chronic HIV infection.
ART-induced decrease in HIV viremia was associated with a significant increase in B cell counts, similar to increases in CD4(+) T cell counts yet distinct from the lack of increase in CD8(+) T cells. The increase in B cell counts was accompanied by a significant decrease in the frequency of apoptosis-prone B cell subpopulations, namely mature activated and immature transitional B cells, which are overrepresented in untreated HIV disease. The increase in B cell counts was reflected by a significant increase in naive and resting memory B cells, both of which represent populations that are essential for generating adequate humoral immunity.
Normalization of B cell counts and subpopulations may help to explain the improvement in humoral immunity reported to occur after an ART-induced decrease in HIV viremia.

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