Evaluation of Clinical, Virologic and Immunologic Factors That Contribute to the Pathogenesis of Chronic Hepatitis C and Its Complications

Hepatitis C virus (HCV) and Hepatitis B (HBV) infection are known to cause morbidity and mortality especially among those who are coinfected with Human Immunodeficiency virus (HIV). HCV infected individuals who are also coinfected with HIV have more rapid progression of liver disease, abnormal diagnostic serologies, higher levels of HCV viremia, and markedly lower levels of therapeutic responses to the standard combination therapy with peginterferon and ribavirin.

The underlying immunopathogenesis of HCV and HBV infection, progression of liver disease, and interactions with HIV are not yet clearly understood. A clear understanding of the immune correlates of protection against HCV and HBV are important in development of a vaccine for HCV and novel immune-based therapeutics for the cure of HBV.

This study will recruit individuals who are coinfected with HIV and HCV and/or HBV as well as those who are monoinfected with HCV or HBV. The study will enroll 2 groups. Participants in the first group (hereafter referred to as Group 1) will consist of participants recruited for research and clinical related blood draws, leukapheresis, and liver biopsies for long term study participation. Participants in the second group (hereafter referred to as Group 2) will consist of participants with known or suspected HCV and/or HBV who need assistance with diagnosis or treatment.

Participants in Group 1 will be apheresed or undergo blood draw several times after enrollment and may be followed for up to 10 years. Participants in Group 2 will be evaluated for HBV and/or HCV infection or complications, or receive treatment. The expectation is that may be followed for one year.

Leukapheresis is used in Group 1 in order to obtain sufficient cells to pursue the following objectives: delineating B cell response to CD4+ T cell help, delineating CD8+ T factors associated with suppression of viral replication and normalization of immune function, characterizing natural killer function relative to HCV and/or HBV disease, and identifying biomarkers for progression of liver disease. The required number of mononuclear cells needed to perform these experiments can be easily and safely obtained using leukapheresis procedures in the Clinical Center Apheresis Unit. Participants who do not meet apheresis criteria may participate through routine blood draws to contribute to this research. All participants in Group 1 may also receive a liver biopsy at NIH (every 3 years for HIV/HCV coinfected and all HBV infected and every 5 years for HCV monoinfected subjects) to assess the progression of liver disease.