Proliferation and Function of CD4+ and T Cells from Chronic Hepatitis B Patients

Objective: Chronic hepatitis B virus infection (CHB) is involved in a deviated immune response to clear the virus. The disease process is caused by CD8+ T cell response. The mechanisms underlying different clinical manifestations of CHB are not clearly known. The present study investigated CD4+ and CD8+ T cell responses to hepatitis B virus (HBV) infection, in terms of cell proliferation and CD69, IL-4, IFN-γ, perforin and granzyme B expression. Methods: A HBV peptide, FLLTRILTI and ionomycin/phorbol myrister acetate and phytohemagglutinin were used to stimulate peripheral blood mononuclear cells (PBMC) from patients with chronic HBV infection. The expression of CD69, IL-4, IFN-γ, perforin and granzyme B as well as cell proliferation was assessed. Results: All subjects had similar CD69 expression and cell proliferation. However, the number of IL-4+ CD4 T cells increased in hepatitis B e-antigen (HBeAg)-positive CHB patients with increased alanine aminotransferase (ALT), HBV carriers, and HBeAg-positive CHB patients with normal ALT. IFN-γ+ CD4 T cells increased in HBeAg-positive and -negative CHB patients with increased ALT and also in HBV carriers. However, granzyme B-positive CD8+ T cells decreased in HBeAg-negative and -positive CHB patients with normal ALT. Conclusion: The present study demonstrated that the different CD4 and CD8 T cell responses may underlie the hepatitis outcomes of CHB. Keywords: CD4 T cell, CD8 T cell, chronic HBV infection, granzyme B, perforin Siriraj Med J 2014;66:1-4