MIRAGLIA AND BERRY 



must have been some studies along this line. 



MIRAGLIA: There have been some studies along these lines, 

 and it appears that there is an increase in the number of phago- 

 cytes when an animal is subjected to cold, but their capacity 

 to phagocytize and digest is greatly impaired. No, we have tried 

 to mimic the effect of cold by using known RES suppressants, 

 such as Proferrin, and we have been somewhat successful in 

 this, but we need to do a great deal more work. 



BERRY: Just by chance, I have a slide. This shows carbon 

 clearance following intravenous injection into mice. Almost com- 

 plete clearance is accomplished in about thirty minutes. Ani- 

 mals kept at 5° C for two hours and eighteen hours were injected 

 with carbon and compared with mice housed at 25° C. There 

 is not a dramatic difference, but it is statistically significant. 

 We have no other data at the present time which evaluates the 

 effect of cold on the activity of the reticuloendothelial system. 

 I was talking with Derrick Roily of the University of Adelaide 

 in Montreal, and he suggested that we use labeled bacterial cells 

 rather than carbon; then, he said, we would probably get a com- 

 pletely different tj^De of result. We shall certainly try to do this 

 very promptly now. 



NUNGESTER: These results were in what animal, and for how 

 long had it been chilled? 



BERRY: The straight line applies to two different groups; 

 mice chilled for two hours, and mice chilled for eighteen hours. 

 The two-hour time period and the eighteen-hour time period 

 gave similar results. We used the two-hour time period be- 

 cause by then the body temperature has dropped, 



MIYA: I'd like to answer Sir Christopher. I don't want to sound 

 like I keep harping on this psychological effect, but if you v/ill 

 recall from the slide with respect to the Klebsiella pneumoniae , 

 the isolated mice, singly caged and immunized, were not pro- 

 tected under acute cold stress. These mice are subject to a 

 stress of cold, a stress of isolation, and a stress of challenge, 

 which makes a total of three stresses; whereas, their counter- 



296 



