Human Red Cell Instability and Senescence 225 



and are made apparent by a progressive increase in the ease 

 of detachment of membrane material by washing or alumina 

 and by the ultimate failure of the cells to survive when trans- 

 fused. These changes can occur at all temperatures between 

 0° and — 78° and are therefore presumably physical in nature, 

 for below — 20° metabolism has effectively ceased. In a 

 personal communication Dr. A. Richardson Jones reports that 

 it is possible to produce a specific anti-serum for the human 

 red cell envelope by immunizing rabbits with alumina powder 

 after its exposure to red cells. The anti- serum has the remark- 

 able property of haemolysing freshly drawn cells but not cells 

 which have been exposed to alumina, repeatedly washed, or 

 subjected to prolonged cold storage. The experimental result 



Fig. 6. The relationship between the rate of spon- 

 taneous haemolysis of red cells at 0° and the recipro- 

 cal of the viscosity of their suspending medium. 

 The cells were suspended in lightly buffered 0-16 

 M-NaCl, pH 7-0, containing 0-1 per cent glucose 

 and various concentrations of glycerol between 

 and 4 • m. 



AGEING VOL. 2 



