S267: PROPERDIN-BLOCKING ANTIBODIES ATTENUATE COMPLEMENT ALTERNATIVE PATHWAY ACTIVATION TRIGGERED BY CELL-FREE HEME IN SICKLE CELL DISEASE MODELS. (23rd June 2022) - Trovati Maciel, T.; Cofiell, R.; Carvalho, C.; Allali, S.; Rignault, R.; Bennet, A.; Dai, Y.; Tamburini, P.; Gasteyger, C.; Hermine, O.; Kim, S. K.