The generation of M2 monocytes in cultures of human peripheral blood mononuclear cells exposed to 137Cs γ-rays (117.2)

Abstract

Abstract Thermally injured patients who are carriers of M2MΦ are greatly susceptible to various opportunistic infections. Since the similarly increased susceptibility to the infection is seen in patients with irradiated injuries, in this study we investigated the effect of 137Cs γ-irradiation on the M2MΦ generation in cultures of human peripheral blood mononuclear cells. Peripheral blood mononuclear cells (PBMC), isolated from healthy volunteers by Ficoll - Hypaque density gradient centrifugation, were exposed to 2 - 8 Gy of 137Cs γ-rays. CD14 positive monocytes were isolated from the irradiated PBMC using magnetic beads, and stimulated with Staphylococcus aureus Cowan strain (0.0075% SAC) for 24 hours. Culture fluids were harvested and analyzed for cytokines by ELISA. In the results, IL-10 was detected and IL-12 was not detected in the culture fluids of monocytes from 137Cs γ-irradiated PBMC, while IL-12 was detected and IL-10 was not detected in the culture fluids of healthy donor monocytes. Also, CCL1 was detected and CXCL13/CCL17 were not detected in the culture fluids of monocytes isolated from 137Cs γ-irradiated PBMC, while all of these chemokines were not produced by healthy donor monocytes. These results suggest that patients with irradiated injuries may be carriers of M2b monocytes.