Regulation by endogenous INTERLEUKIN-10 of the expression of nitric oxide synthase induced after ligation of CD23 in human macrophages.

The possible role of interleukin 10 (IL-10) as an endogenous inhibitor of CD23-driven inducible nitric oxide synthase (iNOS) expression in human macrophages was investigated. Cross-linking of CD23 by a monoclonal antibody induced iNOS mRNA, as detected by RT-PCR, and the production of NO measured as the stable derivative, nitrite. A linear correlation was observed between CD23 expression and iNOS activity or NO2- production.