Primary Antibody Response I N Peritoneal Cells

Since the early days of immunology many workers have tried to initiate and maintain in vitro an immunological response leading to the formation of antibody by cells from nonimmune animals (1, 2). This quest has been revived in the last decade, since immunologists felt the need of such an approach at a cellular level. Various laboratories have succeeded ir maintaining tissues and cells actively producing antibody in culture for various lengths of time (3), while others have been able to bring about antibody production in quiescent tissues and cells previously stimulated in vivo by in vitro contact with specific antigen i.e., a "secondary response" in vitro (4,5). Another line of investigation was to stimulate uncommitted cells in vitro before transferring them to incompetent recipients whose presumed role would be to sustain the life of the "grafted" antibody-producing cells ("immunocytes") (6, 7). A closer approach to the complete in vitro conditions was achieved by using peritoneal chambers in recipients that played the role of "living incubator" for the immunocytes (8, 9). In recent years, some authors have been able to initiate a complete in vitro stimulation of tissue fragments (10-13) or of isolated cells (14-18), from nonimmune animals. In the latter case the antibody production was demonstrated either by detection of antibody activity in the culture fluid (14-15) or associated with the cells (17, 18). This last system, using a method developed in our laboratory (19) for the detection of immunocytes by local hemolysis in gum (L. H. G.), will now be described in detail.