MODIFICATION OF RUNT DISEASE IN MICE BY 

 VARIOUS MEANS 



Paul S. Russell 



Department of Surgery, Columbia University College of Physicians and Surgeons, 



New York 



Studies of the course of events in a newborn recipient mouse 

 following the injection of a population of lymphoid cells make 

 possible an assessment not only of the immunological capacity of 

 the inoculum by its ability to produce runt disease but also of its 

 persistence at full antigenic capacity, most critically assessed by its 

 ability to confer specific immunological tolerance. The latter is 

 not possible in systems using "genetic tolerance" of the recipient 

 rather than immaturity to ensure a hospitable environment to 

 the injected cells. Thus, where adult parental strain cells are admin- 

 istered to adult F] hybrids, for example, the convenient skin graft 

 test is not helpful in demonstrating the persistence of the injected 

 cells which are lost amongst neighbouring cells bearing identical 

 antigens. 



Simonsen has described and used the phenomenon of splenic 

 enlargement in the recipient most effectively in the quantitative 

 assessment of the severity of the reaction of adult lymphoid cells 

 against hosts of varying age and has brought this technique to a 

 stage of considerable refmement (Simonsen, 1957; Simonsen and 

 Jensen, 1959; Simonsen et aL, 1958). The fact that serial observa- 

 tions cannot be made on the same animal makes this method less 

 attractive as a means of following the onward course of the disease 

 in small groups of animals. Although one might be able to follow 

 quantitatively other features of this complex disease (see Howard, 

 1961), the newborn mouse is a small target for analysis and we 



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