Ultra violet radiation-induced defects in accessory cell function in the human proliferative response to tetanus

Ultraviolet B radiation (290-320 nm) has been shown to interfere with accessory cell function of human peripheral blood mononuclear cells in the generation of a proliferative response to tetanus. By altering the timing of irradiation of adherent cells and using short pulses of antigen, we have identified a minimum of two u.v. sensitive accessory cell functions. The first involves antigen presentation and is not readily reversible with time in culture after irradiation. The second is demonstrated by the ability of low doses of u.v. radiation given after the tetanus toxoid pulse to inhibit an event(s) occuring independent of antigen processing. Both occur within a range of doses which would penetrate to the vasculature of the skin of humans exposed to the sun or to phototherapy. (author)