The investigators wish to examine cells from patients infected with HCV g1 and HCV g4 to be able to test and compare the frequency of possible conserved epitopes present in both HCVg1 and HCVg4 infections. Once developed this technique will allow us to examine all virus-specific CD8 T cells present in patients with acute or chronic disease, and on smaller quantities of blood. The development of these technologies will also allow us to tailor such future diagnostic tests to local populations where a viral subspecies is prevalent; for example using North-African HLA alleles for HCVg4 epitopes.