HOMOGRAFT SENSITIVITY IN HUMAN BEINGS* 

 H. S. Lawrence,! F. T. Rapaport,J J. M. Converse and 



W. S. TiLLETT 



Department of Medicine, New York University School of Medicine, New York 



In addition to its fascination as a biological riddle, the homo- 

 graft reaction and its inverse, acquired tolerance, have provided 

 totally new insight into the nature of the normal immune response 

 and its aberration, autoimmune disease (Medawar, 1956, 1958, 



1959). 



At the practical level any efforts designed to ameHorate or 

 suspend this immunologically specific acquired antagonism of the 

 host toward another's tissues will be greatly facilitated by the 

 precise defmition of the antigen or antigens that induce this 

 sensitivity and the antibody or antibodies that function as the 

 instruments of the tissue damage observed (Lawrence, 1956, 

 1959, 1960a). The opening papers of this symposium have dealt 

 with the considerable recent progress made in the difficult problem 

 of identification and characterization of tissue antigens (p. 6, 45, 

 72). The present discussion will concern itself with certain 

 biological and immunological properties of a mechanism of 

 homograft rejection that offers the nearest semblance to an 



* Conducted under the sponsorship of the Commission on Streptococcal 

 Disease, Armed Forces Epidemiological Board, and supported in part by the office 

 of the Surgeon General, Department of the Army, Washington, D. C, and in 

 part by a grant from the National Institute of Allergy and Infectious Diseases, 

 Pubhc Health Service E-1254. This study was supported in part by a training grant 

 E.T.S. 2E-5 from the National Institute of Allergy and Infectious Diseases, 

 National Institutes of Health, Bethesda, Maryland, and in part by grants from the 

 Atomic Energy Commission, Washington, D.C. (AT 30-1-1209), and the Mil- 

 bank Memorial Fund, New York. 



f Senior Research Fellow, United States Public Health Service. 



:j:Lincoln EUsworth Research Fellow. 



271 



