Abstract

The phagocytic activity of neutrophil leucocytes in whole blood is increased in cases of iron-deficiency anaemia. It has been suggested that this is due to some intrinsic change in the leucocytes themselves as a result of anaemia. The present study, however, shows that an artificial reduction of the volume of red cells in normal blood leads to a similar increase in activity. There is no difference in phagocytosis by neutrophils from normal and anaemic blood when the volume of red cells is reduced to a uniformly low level in each case. It is suggested that the increased activity in anaemic blood is due to decreased mechanical interference between leucocytes and particles by the red cells.