In vitro detection of lymphokines produced by in vivo activated lymphocytes

Abstract The purpose of these experiments was to develop a method to measure the production of lymphokines by cells which were activated by antigen in vivo. Previous protocols have been relatively unsuccessful since small, if any, amounts of lymphokines were available for measurement when in vivo antigen activated lymphocytes (AAL) were examined. These unsuccessful expriments usually employed supernatants derived from in vivo AAL which had been cultured in vitro for 2–24 h. As an alternative to assaying supernatants for the presence/absence of lymphokines, we have developed a co-culture system in which the indicator cells are directly added to the wells containing the in vivo AAL. Utilizing this system in conjunction with appropriate neutralizing monoclonal antibodies, we have demonstrated that interleukin-2, interleukin-3 / colony stimulating factor and tumor necrosis factor-α can be readily detected from in vivo AAL.