Interleukin 1-driven secretion of interleukin 2 is highly temperature-dependent

To investigate the temperature dependence of T lymphocyte activation, we have examined the IL 1-induced secretion of IL 2 by the murine T lymphoma cell line LBRM-33-1A5. During 24-hr incubations, there are modest increases in IL 2 secretion as culture temperatures are increased from 33° to 37°C, but IL 2 secretion declines at higher temperatures. However, the kinetics of IL 2 release during the first 8 hr of culture are highly temperature-dependent. The rate of IL 2 release increases linearly with temperature over the range from 33° to 41°C, demonstrating temperature coefficients (Q₁₀) > 70. In contrast, IL 2-promoted proliferation of a continuous T cell line is much less temperature-dependent with Q₁₀ values of <4.0.