Relationship between T lymphocyte responsiveness and T-helper1/T-helper2 type cytokine release in chronic hepatitis C: a critical reappraisal.
Recruitment of virus-specific T lymphocyte subpopulations to liver sites in chronic hepatitis C virus (HCV) infection implies a key role for the immune response in host-virus interaction. In spite of a multispecific and polyclonal cytotoxic function exerted by CD8+ lymphocytes, CD4-mediated activity is weak. This allows the infection to persist which in turn is responsible for the development of chronic hepatitis C (CH-C). Such a finding outlines the occurrence of a possible relationship between cytokine (CK) production by CD4 subsets, i.e. T helper (Th)1 or Th2 cells, and the clinical outcome. A prevalence of Th1-derived CK occurs in infected liver, while increased amounts of Th2-related CK are usually found in peripheral blood. Moreover, peripheral blood mononuclear cell (PBMC) cultures from CH-C subjects exhibit an impaired interferon (IFN)-gamma production and an increase of interleukin (IL)-12 p70 release after stimulation. The latter pattern seems to be due to the enhanced release of IL-12 p40 homodimers, which antagonize IL-12 p70 bioactivity and favour IL-10-induced effects. These results suggest that further extensive studies on the imbalance of the CK network at a molecular level are required to improve the therapeutical approach in CH-C subjects.
Antonaci
S
S
Department of Internal Medicine, Immunology and Infectious Diseases, University of Bari Medical School, Policlinico, Italy.
Piazzolla
G
G
Napoli
N
N
Vella
F S
FS
Fiore
G
G
Schiraldi
O
O
D016207:Cytokines / Q000276:immunology*; D019698:Hepatitis C, Chronic / Q000276:immunology*; D006801:Humans; D013601:T-Lymphocytes / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology
D016207:Cytokines