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 increase 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.