THE DIFFERENT MIGRATORY CHARACTERISTICS OF LYMPHOCYTE POPULATIONS FROM A WHOLE SPLEEN TRANSPLANT.

Spleens from AS × BN donor rats hi belled in vivo by multiple doses of [³H]thymidine were transplanted into syngeneic recipients by anastomosis to the abdominal great vessels. The recipients were killed 1-5 days after receiving the whole spleen transplants and the numbers and location of the [³H]thymidine-labelled cells which had migrated from the labelled donor spleen traced by means of autoradiographs of flections, imprints and smears of various recipient lymphoid tissues. These results were compared with the migration pattern of labelled dissociated spleen cell suspensions injected intravenously. The latter consists almost entirely of small lymphocytes which migrate to T or B areas of recipient spleen, lymph nodes and Peyer's patches. The labeled whole spleens also contained cells which migrated to the T and B areas of recipient lymphoid tissue, but in addition contained many lymphoid cells which migrated to the red pulp of the recipient spleen and to the lamina propria of the gut. These experiments showed, therefore, that the spleen contains mobile elements which have not been detected by transfer of spleen cell suspensions. [ABSTRACT FROM AUTHOR]