Muramyl dipeptide, a stimulator of nonspecific immunity, induces the production of nitric oxide by Rainbow trout (Oncorhynchus mykiss) spleen and head kidney cells in vitro

作者：Zvizdic Melita Zunic^*; Licek Elisabeth; Lam Charles

来源：Veterinarski Arhiv, 2012, 82(6): 617-627.

• macrophages
• immunomodulators
• muramyl dipeptide
• lipopolysaccharide
• nitric oxide
• fish

Immunoenhancing activity of synthetic muramyl dipeptide (MDP) was investigated in relation to the activation of rainbow trout spleen and head kidney T cells and macrophages. Cells cultured with classical T-cell mitogens exhibited significantly higher proliferation rates as compared to those of unstimulated cells. MDP, lipopolysaccharide (LPS) or MDP plus LPS did not stimulate cells to proliferate. In an attempt to show that MDP mediates function of macrophages, we measured the amounts of nitrites, an index of activation of macrophages and nitric oxide (NO) production, in culture supernatants. Incubation of the cells with either LPS, MDP, IFN-gamma and their combinations, resulted in significant and time-dependent accumulation of nitrites in cultures. Taken together, our findings show that MDP is not mitogenic to the fish immune cells, but exerts its effect on macrophages through induction of nitric oxide synthesis. Monitoring of the production of NO can be a novel approach for the measurement of nonspecific immunity in fish.

• 出版日期2012-12