Preservation of intrahepatic hepatitis C virus (HCV)-specific CD4+ T cell responses despite global loss of CD4+ T cells in HCV/HIV coinfection.

Background: Human immunodeficiency virus (HIV) coinfection and low peripheral blood CD4(+) T cell counts are associated with increased hepatitis C liver disease.

Methods: Hepatitis C virus (HCV)-specific CD4(+) T cell responses were assessed using interferon (IFN)- gamma enzyme-linked immunospot assays on peripheral blood mononuclear cells and expanded liver lymphocytes from HCV-monoinfected and HCV/HIV-coinfected subjects. Cell frequencies were determined using flow cytometry.

Decreased NK cell frequency in chronic hepatitis C does not affect ex vivo cytolytic killing.

Prior studies have suggested that natural killer (NK) cell function might be impaired in chronic hepatitis C virus (HCV) infection. Circulating NK cell frequency and cytolytic activity were examined freshly ex vivo in HCV-infected and uninfected subjects. Surprisingly, the intrinsic cytolytic activity of peripheral blood NK-enriched cells was similar between HCV-infected and uninfected groups (P = .