[Immunologic phenomena in guinea pigs injected with homologous ganglia extracts].

Immunological modifications in guinea pigs injected with homologous lymph node extracts. In studies carried out in patients with lymphomas an accentuation of the B2M-globulin line was observed; occasionally paraproteins and isoantibodies were detected. For this reason the authors decided to find out whether the injection of homologous lymph node extracts in guinea pigs would produce serum, immunological and histological modifications comparable to the ones observed in the human being. A total of 100 guinea pigs were divided into 4 groups. Group 1, 50 untrated control animals; Group 2, 10 animals injected with complete Freunds adjuvant every 10 days, for 3 times, and sacrificed 7 days after the last injection; Group 3, 10 animals injected with the antigen prepared with the lymph nodes from normal guinea pigs, in the same way as the preceding group; Group 4, 30 animals injected with the same antigens emulsionated with the adjuvant, again by the same method as the 2 preceding groups. The antigen was prepared with the lymph nodes from normal guinea pigs. The cells were "ultrasonicated" and lyophilized; the lipids were extracted with chloroform. The extract thus obtained contained an average of 2 mg/ml of total proteins. A microimmunoelectrophoretic study (MIE) against rabbit immuno serum for guinea pigs anti-serum proteins, showed that it was contaminated with various serum proteins (fig. 1, A). In the 3 injected groups, most of the guinea pigs showed a 10% decrease in serum protein (Table). Using MIE there was a re-enforcement of the B2M-globulin precipitation line (IgM), in all the animals of groups 2 and 4, as compared to the groups 1 and 3 (Table and figure 1. B and C). Using microdiffusion in agar, the serum of 6% of the guinea pigs of group 4 gave precipitation lines with the homologous antigen (Table, figure 1, D). Using passive hemagglutination, between 30 and 40% of the serum of the animals of all 4 groups gave positive results with the same antigen, with a low titer (1/40). Using complement fixation, positive results were obtained with the lymph node antigen in 10% and 20% of the animals of groups 3 and 4 respectively: from 25 to 50% fixation with a titer of 1/10 (Table). Using immunofluorescence, positive images in the cytoplasm of lymphocytes (from improntas of normal guinea pigs lymph nodes) were obtained only in the labeled gamma-globulin (IgG) of the animals of group 4 (Table and figure 2, C). Histological study of the lymph nodes of guinea pigs from groups 2 and 4 showed hyperplasia of the reticular tissue with apparent decrease in the size of the follicles. In some of the lymph nodes of the animals of group 4, giant cells were observed (Fig. 2, B), pironinophilic. In the group 3 hypertrophy of the lymphoid follicles was observed (fig. 2, A). Non-specific modifications of the serum proteins, similar to the ones observed in patients with lymphomas were detected in some of the animals belonging to groups 2 and 3 in a greater number of animals in group 4. Circulating isoantibodies could be compared to those detected in 2 cases of lymphosarcoma. In spite of definite histological alterations of the lymphatic organs, these cannot be compared with the alterations detected in the human being.