ANTIBODY FORMATION 



mately twice that of room temperature controls. Serum pro- 

 tein concentration also increases. This might be an interesting 

 point also to mention. Animals at high altitude have an increased 

 serum protein concentration and a decreased plasma volume. 

 Animals in the cold also have an increased serum protein con- 

 centration, and an increased plasma volume. Their plasma volume 

 was measured by Evans blue disappearance and also from the 

 passive antibody decay studies. In the latter case, the amount 

 of antibody injected and the initial antibody concentration in 

 the serum are used to calculate "plasma volume", or perhaps 

 we should call it "antibody space", as compared to Evans blue 

 space, 



TUNEVALL: Was the decreased plasma volume at high al- 

 titude simply a result of an adaptive polycythemia? 



TRAPANI: Yes. From the information just given, it was cal- 

 culated that animals at high altitude had a total mass of cir- 

 culating proteins the same as controls, while animals in cold 

 had an increased mass of circulating protein. More specifi- 

 cally, if one makes the proper corrections, the increase in 

 the immune response of animals at high altitude is greater 

 than that which might be expected from a decreased plasma 

 volume. 



PREVITE: Have you ever done any experiments in a shorter 

 period of time? For example, have you ever measured anti- 

 body titers in response to BSA prior to one week, or isn't that 

 a sufficient amount of time to get a response? 



TRAPANI: It's very difficult to detect antibodies before seven 

 days or so. 



PREVITE: Have you ever previously immunized your rab- 

 bits, waited a sufficient amount of time, and then put them at 

 -15° C? 



TRAPANI: Not in the cold. We did one experiment with rab- 

 bits at high altitude simular to what you are thinking about. 

 The first year we took animals up to White Mountain in Cali- 



10 5 



