Immunomodulatory effects of inosine pranobex on cytokine production by human lymphocytes

Inosine pranobex (inosine dimepranol acedoben, isoprinosine) (Inos) is an immunomodulatory and antiviral drug used in some viral infections, especially in patients with weakened immunity. In the present study, effects of Inos on the production of cytokines attributable to Th1 (IL-2, IFN-g, and TNF-a) or Th2 cells (IL-4, IL-5, and IL-10) were tested in human peripheral blood lymphocyte cultures stimulated with phytohemagglutinin (PHA). Inos enhanced TNF-a secretion significantly (in short-term - 24-hour, and prolonged term - 72-hour cultures) and IFN-g (in 72-hour cultures). Surprisingly, production of IL-10 by PHA-stimulated lymphocytes was suppressed by Inos in a dose-dependent manner in both 24-hour and 72-hour cultures. These results shed some light on immunomodulatory properties of Inos and suggest applicability of this agent in patients with a depressed function of the immune system.