Significance of alterations in PBMC immunophenotype of children with chronic viral hepatitis C-- the role of dendritic cells.

There are differences in the clinical course of chronic viral hepatitis C between adults and children, but it is generally accepted that the disease has cell-mediated immune background. The aim of this study was to evaluate PBMC subsets in children with chronic hepatitis C before treatment in order to find some predictive factors, useful for patients management. Several PBMC subsets, in particular lymphoid and dendritic cell (DC) ones, were tested by flow cytometry in HCV(+) paediatric patients (n = 46) and in control children matched in terms of age and sex (n = 20). Data were subjected to extensive statistics. It was found that cells with cytotoxic potential such as CD8(+)CD28(-) T cells, NK and NKT cells as well as lineage(-)HLA-DR(+) DC were increased in per cent values, while CD4(+) T cells and CD4:CD8 ratio were decreased in hepatitis C group. In HCV(+) patients, CD4(+) T cells were inversely correlated with alanine aminotransferase (ALT) levels and with viraemia. DC subset of myeloid origin (CD11c(+)) assessed both in per cent values and as mean fluorescence intensity (MFI) of HLA-DR expression was shown to be downregulated in hepatitis patients, in spite of increased numbers. To conclude, PBMC subsets, and in particular DC, are affected by HCV chronic infection in children, reflected by the correlation with clinical parameters, such as ALT and viraemia.