The factors that determine persistence or clearance of hepatitis C virus (HCV) infection are poorly understood. Information in this area may lead to better understanding of the immune response against HCV infection. Such understanding can support the goal of development of a broad based cellular and humoral immune response to HCV which may be important for eradication of infection.
In the present study, needle biopsy specimens from hepatitis C virus infected patients were prepared for histological, histopathological and immunohistochemical studies. Patient history, full clinical examination and biochemical investigations were recorded.
Primary and secondary lymphoid follicles were evident in ABOUT 50% of the biopsies. Because CD4(+) T- helper (T-h) lymphocytes provide help for humoral immunity, these cells were demonstrated in the liver biopsies by immunohistochemical methods. Positive fluorescence representing CD3(+)/CD4(+) T-h was vigorous in liver residing lymph follicles.
To test the possibility of T-h proliferation due to autoimmune reaction, the serum of patients was tested for the presence of antimitochondrial, antismooth muscle and antinuclear antibodies by immunohistochemical method. Analysis of the results eliminated the autoimmune response leaving the possibility of antiviral response.
Histological examination indicated bile duct injury in areas occupied by secondary follicles. This may indicate that viral core proteins, with antigenic properties that elucidate immune response, may reach the portal area, in which the follicles are formed, via the bile canaliculi to the bile duct where antigen antibody complex is phagocytosed leading to bile duct injury. Unlike the case of patients who did not show follicles in their liver biopsy, those showing secondary follicles did not show liver cirrhosis or high grade fibrosis suggesting immune protection. Moreover, the incidence of secondary follicles in females was higher than males suggesting sex-dependent immune response. The present study calls for more investigation towards the understanding of the possible immunity and vaccination against virus
C hepatitis which may lead to eradication of its infection.