Microincision of sickled erythrocytes by a laser beam.

Increased mechanical fragility of the sickled red cell is thought to be important in the genesis of the hemolytic process in sickle-cell disease. Sickled cells were observed cinematographically after microincision by a ruby-laser beam. Distortion and charring invariably occurred at the site of injury, and with small injuries there was no further cell change. With larger injuries, variably rapid retraction of spicules occurred accompanied by sphering of the cell. In some cases, progressive loss of hemoglobin accompanied and followed the changes in shape; in others the sphered cell still contained hemoglobin. Regardless of the mecha nisms involved in these changes in vitro, the observations may be applicable to destruction of sickled cells in vivo. We suggest that the cells are subject to avulsion of rigid cellular processes as a result of mechanical injury incurred in normal circulation. Such injured cells may undergo either immediate hemolysis or trans formation into spherocytes which are subject to erythophagocytosis.