[The role of NF-kappaB transcription factor in chronic viral hepatitis C and B].

Essential data pertaining to the structure and function of selected transcription factors such as NFAT, AP-1 and NF-kappaB in particular, are presented in the relation to viral hepatitis C and B. In chronic hepatitis C the activation of NF-kappaB is markedly modulated by viral proteins such as core protein and nonstructural ones, particularly NS5A and NS3. In hepatitis B the major factor influencing NF-kappaB function appears to be HBx protein. Effects of viral proteins on NF-kappaB function in relation to the course of hepatitis are complex. They participate in the perpetuation of inflammatory state in the liver, inhibit apoptosis of hepatocytes, as well as the differentiation of antigen-presenting cells (dendritic ones). The latter effect has deleterious impact on the formation of specific immune response to viral peptides. It seems that both viruses, C and B acquired the ability to modify NF-KB function in advantage for the pathogens in question.