242 Discussion 



Lovelock had the same kind of result, in that to start with there was a 

 rapid loss of lipoprotein from the cell without anything very much 

 happening to it. But according to Lovelock, after 5 washings — between 

 5 and 20 washings — the further loss of lipoprotein, which was not very 

 great, was paralleled by a loss of haemoglobin which means haemolysis. 



Mollison: There is more direct evidence which makes me doubt that 

 a loss of lipids is important. Lovelock, I think, was using fresh cells in 

 the experiment quoted. When he dealt with stored cells, he found much 

 greater loss of lipids. We have recently done some experiments where 

 we have seven times washed cells stored for about five weeks and we 

 have obtained just the results we expected with unwashed cells. So 

 I still do not know how important this loss of lipids is in practice. 

 Similarly, in some of the cases of ours in which Lovelock actually 

 estimated lipids on the stored cells, we sometimes found poor survival 

 when there was very little loss of lipids. So that although of course 

 I do not doubt the fact that red cells do lose lipids, I am not sure 

 whether this is a thing which limits their survival in practice. 



Williams: Is the red cell without a nucleus a living cell? I should have 

 thought it was not. Surely one of the essential qualities of the living cell 

 is, in fact, this synthesis of enzymes. After all, if you incubate enzymes 

 in vitro, metabolic activity goes on. I should have thought that directly 

 it has lost the nucleus, it is, in fact, a dead cell and you are dealing with 

 physicochemical changes and not with biophysical. 



Mollison: Would you agree that the synthesis of adenosine triphos- 

 phate is a surprising thing for a dead cell to do ? 



Williams: I can imagine it happening in vitro in an enzyme system 

 and with the appropriate substrates. 



Mollison: No one has claimed that the red cell is alive. I am sorry, 

 it is very loose terminology. 



Parkes: The problem of whether or not the red cell is a living one 

 seems to be perennial. 



Yemm: Has it a protein turnover? 



Mollison: I think probably not. Once it has lost its reticulum it does 

 not synthesize any more haemoglobin; in fact I do not think it can 

 synthesize protein at all. 



Villee: No, it does not, because its life-span can be estimated from 

 the incorporation of amino acids into the protein part of the globin. 



Mollison: That is quite right. 



Williams: Surely it has none of the properties of a living cell, the chief 

 properties of which are growth, reproduction, movement and activity. 



Parkes: I think Lovelock would say he would not care whether it is 

 alive or dead; it has enabled him to do physicochemical work with 

 results that do appear to be applicable to what are obviously living cells. 

 It has been found, for instance, that the work on the human red cell 

 was directly applicable to the spermatazoa of the herring. And, as a 

 result of the work on the red cell, the marine biologists are beginning 

 to cross spring and autumn spawning races of herrings which they have 

 never managed to do before. 



Hnggett: It would be begging the question, would it not, to say that 



