Sodium azide enhancement of interleukin-2 production

The production of large quantities of Interleukin-2 (IL-2) from normal human lymphocytes has been limited by the short production and release period, as well as its absorption by the responsive cell population. We report the utilization of sodium azide (NaN₃, 0.01% final concentration) to allow continued production of IL-2 as long as 72-96 hr and thereby increased the yield significantly. Cell cycle analysis performed by flow cytometry indicates that NaN₃ blocks cells at the G₀-G₁ transition and the G₁-S transition, depending on the time of addition of NaN₃ to the cultures.