235 



3" cx])rc'.sscs Ihc dirccl cltccl ot aiitifrcn on llic iiniminizcd 



2 



fibroblasts. 



n- expresses the elleel of the (f)xie concenlralion ol anli- 



gen on normal fibroblasts. 



In addition to these experiments willi llie action of 

 foreign protein on tissue cells in vitro, it miisl be mentioned 

 that (barrel and K 1) e 1 i n g ■'') found that casein inoeuhited 

 into a culture of leucocytes brings about an immediate in- 

 crease in the substances which jiromote the growth of fibro- 

 blasts and natural hemolysins. The cells respond imme- 



.2 1 



1 



8 



Passac5e 



Fig. 55. 

 Curve 1 shows the variations in the quotient of the rate of growth of the 

 immunized strain in a small amount of antigen divided by the rate of growth 

 of the same strain in a high concentration. Curve 2 shows the variations in 

 the quotient of the rate of growth of Ihe non-immunized strain in ordinary 

 medium divided by the rate of growth of the same strain in a high con- 

 centration of antigen. Dog serum was used as antigen in a concentration 

 of 4 per cent The ordinates represent the quotient or the rates of growth, 

 and the abscissae the number of passages. 



diately and non-specifically to tlie foreign substances. These 

 experiments by Carrel and Ebeling indicate a ([uite 

 new field of investigation namely the therapeutic action of 

 non-specific foreign i)roteins. This cpiestion would have an 

 ideal method in the tissue cultivation. 



