ABSTRACT
Hepatitis C virus [HCV] infection is associated with immune mediated abnormalities and B- cell lymphoproliferation. CD81 was identified as an HCV receptor on B-lymphocytes. The antigen CD19 is associated with CD81 B-cells at different stages of maturation. Expression of CD5 lymphocytes was associated with non- HCV related autoimmune disorders. Therefore we try to evaluate the clinical significance of B-lymphocyte phenotyping of peripheral blood [PB] in HCV- infected patients [age range 10-16 Years] with and without the autoimmune markers rheumatoid factor [RF], antinuclear antibody [ANA], and anti-double stranded DNA [Anti ds DNA], where PBCD5, CD19 and CD81 expression were determined in 20 EDTA blood samples of healthy persons [group I] and 40 blood samples of HCV- infected persons [25 with negative autoimmune markers [group IIa] and 15 with positive autoimmune markers [group IIb]]. Age [10-16 years]. Flow cytometry was used to estimate percentage of antigen expression of CD5, CD19 and CD81 over B-lymphocytes. Indicated that CD5 expression was significantly increased in group IIb than group IIa and group I [28 +/- 3.2%, 25 +/- 4.2% and 13.3 +/- 5.8% respectively p < 0.0001]. The same increase occurs in the mean values for CD19 [group I 3.5 +/- 1.6%, group IIa 14 +/- 2.5% and group IIb 23 +/- 3.1% p< 0.0001], while CD81 mean values were group I 50 +/- 28%, group IIa 78 +/- 16% and group IIb 92 +/- 12%. Increased expression of CD5, CD19 and CD81 on B-lymphocytes in HCV- infected patients with higher values with positive autoimmune markers, suggests the high clinical significance of peripheral blood B-lymphocyte phenotyping as a predictive and diagnostic tool for autoimmune serconversion in HCV-infected patients. Also it can be a prognostic guide for successful treatment or highlight for new antiviral and autoimmune treatment