Further Characterization of the Lymphoid Cell Transfer System for the Study of Antigen-Sensitive Progenitor Cells

Abstract

Summary Further characterization of a lymphoid cell transfer system, a system in which heavily x-rayed syngeneic mice served as passive recipients for the antibody expression of transferred spleen cells, revealed the following: Most of the serologically detectable hemagglutinins and hemolysins released into the blood during the 1st week after cell transfer were synthesized by the repopulated spleen.Only a small fraction of the transferred immunocompetent cells colonized initially in the spleen. This fraction was estimated to be about 10% on the basis of the double spleen cell transfer method. This serologic appraisal was in striking concordance with the estimate based on the number of hemolysin plaque-forming cells in the repopulated spleen.The accuracy of these estimates was dependent upon spleen cell dose and, in the case of nenprimed spleen cells, also on the time when the repopulated spleen was removed from the primary recipient.The effect of the colonizing density on the ratio of the maximum number of hemolysin plaque-forming cells in the spleen to the unit number of spleen cells transferred was as follows: the ratio was large and constant at optimal spleen cell doses, but relatively small and variable at limiting spleen cell doses.