IL15 and HIV infectious disease: Tarkowski et al. [133] found that the expression of IL-15, but not of its receptor IL-15Rα, was significantly higher in the CD14+ monocytes of long-term nonprogressors than in those of HIV-1 progressors or healthy controls; differences in IL-15 expression between patients with different courses of HIV infection may be indicative of a potential use of this cytokine as a therapeutic agent.