Fission and refusion of red blood cells using a micropipette technique

In micropipette experiments with small capillaries and moderate high pressure difference (approximately 1000 Pa) cell fragmentation (fission) of human red blood cells without hemolysis was observed by TV-system for a large number of fresh red blood cells of different donors. After separation, the fragment moves away from the residual cell. In seven cases this process was evaluated quantitatively and was shown that the rate of the fragment was constant in time. Two mechanisms for this phenomenon are discussed. In particular cases a spontaneous re-fusion with the residual cell body in the capillary can be observed. In our opinion probably protein-depleted membrane surfaces arise and membrane fusion is possible simply by mechanical contact without additional electric fields and/or fusion agents.