PREFACE 



Far-reaching advances in our knowledge of the lymphocyte have merited 

 this present evaluation. First, Downey and his students supplemented in- 

 formation gained by histologic techniques with the advanced cytologic 

 information to be obtained by imprints of lymphocytic tissues. Next Dough- 

 erty and White and the Harrises demonstrated antibody formation by lym- 

 phocytes. Soon thereafter study of human skin windows revealed that 

 lymphocytes were the major mobile source of macrophages in the inflamma- 

 tory exudates of man. Integrated with all these findings was the realization 

 afforded by the work of Ottesen and Hamilton of an exceptionally long life 

 span possessed by lymphocytes, a life span now measured in weeks and 

 months instead of in hours or days. The viral etiology of neoplasms of the 

 lymphocyte is now well documented by the experiments of Gross and 

 Schwartz. Added to these must be the ultrastructural descriptions of Bessis 

 and Low, the ascertainment by Dougherty and his associates of an exquisite 

 sensitivity of normal lymphocytes to certain steroids notwithstanding the 

 refractoriness of their leukemic counterparts, the somewhat similar re- 

 sponse to irradiation pointed out by Schrek — all are facets of the newer 

 knowledge of the lymphocytes presented in the following pages. 



John W. Rebick 

 Detroit 



XI 



