P-229 Poster of distinction

Expression of receptors for anaphylatoxins C3a and C5a on islet preparations

K. Tokodai, M. Goto, A. Inagaki, W. Nakanishi, S. Satomi
Tohoku University, Sendai, Japan

Objective: Complement activation has been implicated in the development of the instant blood-mediated inflammatory reaction (IBMIR). Especially anaphylatoxins C3a and C5a elicit a broad range of pro-inflammatory effects including chemotaxis of inflammatory cells and cytokine release. We have shown that 2 types of receptors for C5a are expressed on isolated islets (Transplantation:2010:90:1358-1365). In the present study, we investigated this component in detail.
Methods: C3aR, C5aR and C5L2, together with CD11b and CD31, on freshly isolated islets (fresh group) and islets cultured with (cytokine group) or without (culture group) TNF-?, IL1-?, and IFN-? for about 12 h were analyzed by flow cytometry. In addition, these 3 kinds of receptors on nonendocrine cells were also analyzed.
Results: C5aR and C5L2 were expressed on the isolated islets (C5aR: 7.91 ± 2.83%, C5L2: 2.45 ± 1.34%, respectively) and the expression of both C5a receptors was markedly attenuated by cultured for 12 h (C5aR: p<0.005, C5L2: p<0.05, respectively). Compared with the culture group, the expression was significantly up-regulated in the cytokine group (C5aR: p<0.05, C5L2: p=0.05, respectively). C5aR positive cells expressed CD11b, but not CD31. Contrary to islets, nonendocrine cells expressed C5L2 predominantly (C5aR: 1.51 ± 0.87%, C5L2: 4.58 ± 2.19%). C3aR was scarcely expressed on the isolated islets or nonendocrine cells.
Conclusions: These data suggest that C5aR and C5L2 are expressed on CD11b positive leukocytes in islet preparations. Depletion of C5a receptors by culturing appropriately could be an attractive therapeutic strategy in clinical islet transplantation.

P-229 Poster of distinction

Expression of receptors for anaphylatoxins C3a and C5a on islet preparations

K. Tokodai, M. Goto, A. Inagaki, W. Nakanishi, S. Satomi
Tohoku University, Sendai, Japan

Objective: Complement activation has been implicated in the development of the instant blood-mediated inflammatory reaction (IBMIR). Especially anaphylatoxins C3a and C5a elicit a broad range of pro-inflammatory effects including chemotaxis of inflammatory cells and cytokine release. We have shown that 2 types of receptors for C5a are expressed on isolated islets (Transplantation:2010:90:1358-1365). In the present study, we investigated this component in detail.
Methods: C3aR, C5aR and C5L2, together with CD11b and CD31, on freshly isolated islets (fresh group) and islets cultured with (cytokine group) or without (culture group) TNF-?, IL1-?, and IFN-? for about 12 h were analyzed by flow cytometry. In addition, these 3 kinds of receptors on nonendocrine cells were also analyzed.
Results: C5aR and C5L2 were expressed on the isolated islets (C5aR: 7.91 ± 2.83%, C5L2: 2.45 ± 1.34%, respectively) and the expression of both C5a receptors was markedly attenuated by cultured for 12 h (C5aR: p<0.005, C5L2: p<0.05, respectively). Compared with the culture group, the expression was significantly up-regulated in the cytokine group (C5aR: p<0.05, C5L2: p=0.05, respectively). C5aR positive cells expressed CD11b, but not CD31. Contrary to islets, nonendocrine cells expressed C5L2 predominantly (C5aR: 1.51 ± 0.87%, C5L2: 4.58 ± 2.19%). C3aR was scarcely expressed on the isolated islets or nonendocrine cells.
Conclusions: These data suggest that C5aR and C5L2 are expressed on CD11b positive leukocytes in islet preparations. Depletion of C5a receptors by culturing appropriately could be an attractive therapeutic strategy in clinical islet transplantation.