THF gamma 2 stimulates cytokine release by peripheral blood mononuclear cells of patients with chronic hepatitis B virus infection.

A recent study indicated that thymic hormones have antiviral effects in human hepatitis B virus infection and woodchuck hepatitis virus infection. These hormones are known to exert immunomodulatory effects on lymphocyte maturation and function; because these are abnormal in patients with chronic hepatitis B virus infection, we have examined the effects of a thymic hormone (THF gamma 2) on peripheral blood mononuclear cells from patients with chronic hepatitis B virus infection. THF gamma 2 (50 or 150 ng/ml) alone was without effect; in the presence of low doses of the mitogen phytohaemagglutinin, it had a broad effect in patients and controls. The effect on interleukin-2 production was greater in patients than controls with a significant increase in production at 150 ng/ml for patients alone (p = 0.037). Tumour necrosis factor alpha production was enhanced in all patients and controls, with a greater effect seen at 150 ng/ml THF gamma 2 than 50 ng/ml. There was no effect on interferon gamma production or on the expression of membrane markers of T-cell activation. THF gamma 2 has substantial immunomodulatory activity in chronic hepatitis B virus carriers and in vivo assessment of THF gamma 2 in chronic hepatitis B virus is indicated.