Hepatitis C virus core protein thwarts effector cytotoxic T-cell differentiation.

2004 APR 7 - (NewsRx.com & NewsRx.net) -- Hepatitis C virus core protein thwarts effector cytotoxic T-cell differentiation.

"In a companion study, we showed a dichotomy between the expansion of central memory (CCR7[superscript]+) hepatitis C virus (HCV)-specific cytotoxic T lymphocyte (CTL) and the incomplete memory effector differentiation in patients with acute HCV infection. Indeed, effector cells were unable to perform immediate functions, despite expressing the tissue-homing phenotype of effector memory cells (CCR7[superscript]+; semi-effectors). However, since they promptly differentiated into full-effectors upon interleukin (IL)-2 contact, we suggested that the inhibitory effect by environmental (possibly viral) factors on IL-2 production may have a pivotal role in generating the large population of semi-effector CCR7[superscript]-/IFN-gamma[superscript]- CTL," scientists in Italy report.

"In accord with this view, we report here strong evidence in support of circulating HCV core protein (HCVcore) playing a central role in inhibiting effector CTL differentiation, but not memory CTL expansion. The regulatory HCVcore effect is related to inhibition of the signal transduction pathway instrumental for IL-2 production, supporting the evidence that IL-2 was capable both of ...