Interestingly, CD4+ T cells were more frequent in the livers of patients with FHF due to HEV and CD8+ T cells have been shown to infiltrate the livers of patients with fulminant hepatitis E. Hence, it is suggested that cytotoxic T cells (CD8+) could be playing a major role in the pathogenesis of fulminant hepatitis. The gene discussed is CD8A; the disease is TNF receptor 1-associated periodic fever syndrome.