New insight into role of mast cells in erythrocyte homeostasis and clearance under oxidative stress conditions in vivo.

Erythrocytes are exposed to reactive oxygen species during circulation constantly, due to normal aerobic cellular metabolism and pathology of inflammatory diseases. Genetic depletion of mast cells and systemic mastocytosis seem to affect anaemia. We attempted to reveal the participation of mast cells in erythrocytes clearance in vivo and during interaction with professional phagocytes like macrophages in vitro. Mastocytosis was induced in DBA/2 mice by injecting P815 cells and mast cell depletion was attained with compound 48/80 treatment under normal or phenylhydrazine (PHZ) induced oxidative stress conditions in mice. The mastocytosis model showed a significant decrease in circulatory erythrocytes while mast cell absence led to significantly high accumulation of erythrocytes in spleens of mast cell depleted anemic mice. The present study provides important evidences for contribution of mast cells in erythrocyte clearance during oxidative stress conditions and augmented uptake of oxydatively damaged erythrocytes (ODE) in presence of macrophages in close proximity.