FEVER AND IMMUNOREGULATION - HYPERTHERMIA, INTERLEUKIN-1 AND INTERLEUKIN-2 AND T-CELL PROLIFERATION

Abstract

The possible role of fever in host defense is poorly understood. Fever in response to exogenous agents is mediated by a host macrophage product called endogenous pyrogen (EP). EP is probably indentical to interleukin 1 (IL1), an immunostimulatory macrophage product that induces T-cell proliferation. The pyrogenic and immunostimulatory actions of this host mediator might be interrelated and tested T-cell proliferation induced by IL1 at a temperature characteristic of fever. The [murine] T-cell proliferative response to IL1 (and to the lymphokine, IL2) was greatly increased at 39 vs. 37.degree. C, while B-cell mitogenesis in response to lipopolysaccharide was not. If similar events occur in vivo, fever may have important immunoregulatory significance, the current indiscriminate use of antipyretic agents was questioned.