Immunity of Rats towards Jensens Rat Sarcoma. 27 





By 

 admixture 

 with spleen 

 cells before 

 inoculation. 



Some accu- 

 mulation of 

 lymphocytes 

 3rd-ith day. 



Delayed 

 growth of 



sarcoraa, but 

 production 



of a tumour. 



May be 

 either 

 susceptible 

 or immune. 









)re inoculation 



By exposure 

 to radium 

 sufficient to 

 produce 

 delay ot 

 growth of 

 a tumour. 



Some accu- 

 mulation 



5th-6th day, 

 but 



subsequently 

 disappear. 



Slow 

 division ot 

 sarcoma 

 cells and 

 production 

 of a tumour. 



May be 

 either 

 susceptible 

 or immune. 





have not been carried out. 





Us altered bef( 



By exposure 

 to radium 

 sufficient to 

 prevent the 

 formation 



Great accu- 

 mulation of 

 lymphocytes 

 on about ■ 

 the 5th day. 



Some division 

 of sarcoraa 

 cells outside 

 the cleft, but 

 subsequently 

 disappear. 



Animals 

 usually 

 Immune. 







)he sarcoma ee 



By exposure 

 to radium 

 sufficient to 

 prevent the 

 division 

 of cells. 



Some 

 accumula- 

 tion of 

 lymphocytes 

 3rd-4th day. 



No division 

 of sarcoraa 



cells ; some 



outside 

 the cleft. 



Animal 

 remains 

 susceptible. 





Experiments 







Killed by 

 exposuie to 

 heat. 



Very few 

 lymphocytes 

 in reaction 

 tissue. 





No growth 

 of sarcoma 

 cells ; none 



outside 

 the "cleft." 



Animal 

 remains 

 susceptible. 









a 



o 



By exposure 

 to X-rays for 

 J hour. 











Accumulation 

 delayed to 

 5th or 

 6th day. 



Divisions of 

 sarcoma cells 

 outside the 

 cleft up to 

 5th day ; 

 subsequently 

 die out. 



Animal 

 remains 

 immune (few 

 experiments 

 only). 



before inoculatii 



By exposure 

 to X-rays for 

 Ij hours. 





red animals. 



ot carried out. 



Accumulation 

 delayed 

 to about 

 14th day. 



Sarcoma cells 

 divide and 

 produce a 

 measurable 

 tumour which 



subsequently 

 regresses. 



Animal 

 remains 

 immune (few 

 experiments 

 only). 



e animal altered 



By a large 

 inoculation. 





As in unalte 



Experiments n 



Accumulation 

 delayed to 

 4th or 

 5th day. 



Division of 

 sarcoma cells 

 outside cleft 

 up to 4th day ; 

 subsequently 

 die out. 



Animal 

 remains 

 immune. 



si 



splenectomy. 











Accumula- 

 tion of 

 lymphocytes 



delayed to 

 5th or 6th day. 



Division of 

 sarcoma cells 

 outside cleft 

 up to 5th day ; 

 subsequently 

 die out. 



Animal 

 remains 

 immune. 



No 

 alteration 

 before 

 inoculation. 



Very few 

 lymphocytes 

 in the 

 reaction 

 tissue. 



Sarcoma 



cells 

 multiply 

 and form a 

 tumour. 



The animal 

 may be 

 either 

 susceptible 

 or immune. 



Great 

 accvimula- 

 tiou of 

 lymphocytes 

 2nd or 

 3rd day. 



A few 

 sarcoma 

 cells outside 

 the "cleft"; 

 none divide. 



Animal 

 remains 

 immune. 







The role of 



the 

 lymphocyte. 



The 

 behaviour 

 of the 

 sarcoma cell. 



The 

 subsequent 

 susceptibility 

 of the 

 animal. 



The role of 



the 

 lymphocyte. 



The 

 behaviour 

 of the 

 sarcoma cell. 



The 

 subsequent 

 susceptibility 

 of the 

 animal. 







■sjBUitUB atqicjdaosns ui 



•siumiuB 9unuiuii ni 



