Immunopathogenesis of chronic hepatitis B and C in children Iwona Mozer-Lisewska, Arleta Kowala-Piaskowska, Jan Żeromski Medical Science Review - Hepatologia 2010; 10 13-17 aaICID: 911663
Article type: Review article
IC™ Value: 3.34
Abstract provided by Publisher
Basic facts related to the pathology and clinic of viral hepatitis were presented.
Biological/structural similarities and differences of hepatotropic viruses, HBV and HCV and features of adaptive immunity to viral antigens were described. Immune response is weak in patients, as the percent of sensitized T cells is 1–2% only. This explains low number of patients totally eliminating viruses from the body. Children infected vertically develop tolerance to viral antigens, what limits formation of specific immune response. Moreover, the immune system of a child is partly immature functionally. All of this explains the growing interest in innate immunity. The latter is filogenetically older than the adaptive one, able to recognize self or non-self only, but possess the large repertuar of humoral and cellular protective factors acting immediately and being present at the time of birth. Many of them are present in the liver such as NK and NKT cells, IP-10 and Mig chemokines and other. Liver dendritic cells act as APC and are the source of 20–30 cytokines, crucial for the quality of antigen presentation and for APC-T cell interaction. NK and NKT cells are able to eliminate infected hepatocytes. Conversely, some viral proteins may inhibit NK cell function. Novel issue is the role of Toll-like receptors (TLR) shown in HBV/HCV infected liver. TLRs recognize so-called pattern recognition receptors (PAMPs) such as nucleic acids, glycolipids or sugars, necessary for pathogen growth and survival. Thus, the data presented indicate that mechanisms of innate immunity may have significant impact on the course of infection by hepatotropic viruses.