Article

In vivo decrease in the expression of complement receptor 2 on B-cells in HIV infection.

Department of Pediatrics, Rush-Presbyterian-St Luke's Medical Center, Chicago, Illinois 60612.
AIDS (impact factor: 6.24). 02/1993; 7(1):37-41. pp.37-41
Source: PubMed

ABSTRACT To investigate changes in the expression of complement receptor 2 (CR2) on B-cells from HIV-infected individuals. CR2 is the C3d/Epstein-Barr virus receptor and has been implicated in B-cell activation. Changes in its level of expression may therefore be associated with B-cell dysfunction.
Cross-sectional study of HIV-infected adults and age-matched control donors.
The percentage expression and mean fluorescence intensity of CR2 (and three additional markers: CD19, CD69, and a standard antigen designation: HLA-DR) was measured on CD20+ B-cells using a two-color flow cytometric assay.
This study demonstrated a highly significant (P = 0.0001) decrease in the percentage co-expression of CR2 on CD20+ B-cells in HIV-infected individuals, compared with control donors. The mean percentage of CD20+ cells co-expressing CR2 was 71% (s.d., +/- 15%) in the HIV-seropositive patients and 94% (s.d., +/- 4%) in the control group. The pattern of CR2 expression in a number of the patients suggested a decrease in antigen density on the cells. Decreased expression of CR2 did not correlate with disease stage (asymptomatic, AIDS-related complex, or AIDS), nor with CD4+ T-cell percentage or absolute count, in the seropositive group.
The evidence for a role for CR2 in B-cell activation suggests that its decreased expression, which we have demonstrated in HIV-seropositive individuals, may be associated with the B-cell dysfunction observed in HIV infection. Our finding that expression of this marker is decreased even in asymptomatic patients is consistent with reports of early B-cell defects in such individuals. Further investigation of this possible association may shed some light on both the increased incidence of bacterial infections in HIV-infected adults and children and their impaired responses to certain immunizations.

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    [show abstract] [hide abstract]
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Keywords

additional markers
 
age-matched control donors
 
AIDS-related complex
 
asymptomatic patients
 
B-cell dysfunction
 
B-cells
 
C3d/Epstein-Barr virus receptor
 
CD20+ B-cells
 
CD20+ cells co-expressing CR2
 
CD4+ T-cell percentage
 
certain immunizations
 
CR2 expression
 
Cross-sectional study
 
Decreased expression
 
HIV-seropositive patients
 
percentage co-expression
 
percentage expression
 
receptor 2
 
standard antigen designation
 
two-color flow cytometric assay
 

M E Scott