CD4 and infection: The relative effect of helper CD4+ cells in spontaneous clearance of acute HCV infection was observed by Smyk-Pearson et al. and established the although HCV-specific CTLs are present during infection, and they are able to produce IFN – γ, proliferate, have cytotoxic behaviour but they still did not certify resolution of infection, but either these CTLs are initially primed with CD4+ T cell help or not was a vital factor36.