Viral Vaccines and CTL Response

Table 3

Immunity to Hepatitis C Virus—A Flavivirus with no vaccine [9, 22].

(i)	60%–80% of patients remain chronically infected and suffer consequences
(ii)		Patients who do recover develop multiepitope-specific CD8+ and type 1 CD4+ T cells
(iii)	Neutralizing Ab production takes 6–8 months and highest titers occur in chronics. Recovered patients may test negative
(iv)		Abs always gone by 10–20 y, but specific T cells persist for life in liver (in chimps)
(v)	Chimps without CD4+ or CD8+ T cells fail to control infection
(vi)		Escape mutants for Ab and T cells occur readily