278 H. S. LAWRENCE ET AL. 



and to streptococcal proteins will transfer sensitivity to both 

 antigens. However, when the same donors are desensitized to 

 tuberculin to the point where the tubercuHn skin reaction is lost, 

 their leucocytes also become selectively desensitized to tuberculin 

 and are then capable of transferring sensitivity only to strepto- 

 coccal proteins (Ohveira-Lima, 1958). 



It should be noted in this regard that in all of our own transfers 

 of delayed sensitivity to bacterial and fungal antigens, the leuco- 

 cyte donor is taken as he occurs in Nature. The transfer of skin 

 homograft sensitivity required a departure from this principle 

 in so far as the leucocyte donor had to be actively sensitized in the 

 period before leucocyte transfer. A summary of the results upon 

 which this discussion has been based is set out in Table II. 



Table II 



Summary of results of transfer of specihc sensitivity to 

 skin homografts* 



Results of transfer 



Mode of sensitization No. of 



and time of collection of Method of No. of positive 



WBCfrom donor transfer Material used for transfer recipients transfers 



First-set rejection Systemic Sensitive WBC extract 2 o 



Second-set rejection Systemic Sensitive WBC extract 2 o 



First- and second-set Local Sensitive WBC extract 4 4 



rejection Non-sensitive WBC 



extract 2 i 



Sensitive WBC extract 



on control graft 4 o 



Sensitive serum on test 



graft 3 o 



Fourth-set rejection Systemic Sensitive WBC extract 6 6 



II days after fourth- Systemic Sensitive WBC extract 4 o 



set rejection 

 5 days after fourth-set Systemic Sensitive WBC extract 4 o 



"white-graft" 

 application 



Sensitive plasma and 

 RBC I o 



* Reproduced from Lawrence et al. (i960) with permission from the Journal of Clinical 

 Investigation. 



