Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Macrophage pro-inflammatory cytokine secretion is enhanced following interaction with autologous platelets. | Scull et al. Journal of Inflammation 2010 7 53 http content 7 1 53 JOURNAL OF INFLAMMATION RESEARCH Open Access Macrophage pro-inflammatory cytokine secretion is enhanced following interaction with autologous platelets Christopher M Scull William D Hays Thomas H Fischer Abstract Background Macrophages are the dominant phagocyte at sites of wound healing and inflammation and the cellular and acellular debris encountered by macrophages can have profound effects on their inflammatory profile. Following interaction with apoptotic cells macrophages are known to switch to an anti-inflammatory phenotype. Activated platelets however are also a major component of inflammatory lesions and have been proposed to be pro-inflammatory mediators. In the present study we tested the hypothesis that macrophage interaction with activated platelets results in an inflammatory response that differs from the response following phagocytosis of apoptotic cells. Methods Human monocyte-derived macrophages hMDMs were co-incubated with autologous activated platelets AAPs and the platelet-macrophage interaction was examined by electron microscopy and flow cytometry. The cytokines TNF-a IL-6 and IL-23 were also measured during LPS-activated hMDM co-incubation with AAPs which was compared to co-incubation with apoptotic lymphocytes. Cytokine secretion was also compared to platelets pre-treated with the gluococorticoid dexamethasone. Results Macrophages trapped and phagocytized AAPs utilizing a mechanism that was significantly inhibited by the scavenger receptor ligand fucoidan. LPS-induced macrophage secretion of TNF-a IL-6 and IL-23 was inhibited by co-incubation with apoptotic cells but enhanced by co-incubation with AAPs. The platelet-dependent enhancement of LPS-induced cytokines could be reversed by pre-loading the platelets with the glucocorticoid dexamethasone. Conclusions The interaction of human macrophages with autologous platelets results in .
