Synthesis of antibodies and immunoglobulins bearing recipient allotypic markers and donor idiotypic specificities in irradiated rabbits grafted with allogeneic cells from hyperimmune donors

Irradiated rabbits were grafted with a mixture of bone marrow, lymph node and spleen cells from donors hyperimmunized against tobacco mosaic virus (TMV). Recipient and donors were characterized by different allotypic specificities. Antibodies synthesized in the recipients display allotypic markers from the recipients but idiotypic specificities cross-reactive with those of donor antibodies. The results show that the differentiation of new host B cells is influenced by the presence of donor memory cells and are interpreted in the light of network concepts.

Synthesis of high affinity antibodies in irradiated rabbits grafted with allogeneic cells from hyperimmune donors

Irradiated rabbits grafted with allogeneic lymph node, spleen and bone marrow cells from a donor rabbit hyperimmunized against tobacco mosaic virus synthesize high affinity antibodies, displaying mainly recipient allotypic specificities, after antigen boosting. By contrast, recipient rabbits from non-immune donors synthesize antibodies of lower affinity. It is suggested that the differentiation of new emerging host B cells is specifically influenced by the presence of donor-memory cells.

High number of antigen binding cells in unimmunized mice and possible occurrence of multispecific lymphocytes

A high frequency of Tobacco Mosaic virus (TMV) binding cells was found in spleen cells from unimmunized mice (about 3 to 4%). TMV binding is strongly inhibited by previous incubation with anti immunoglobulin antisera. After stripping of membrane receptors, a full recovery for antigen binding capacity can be observed after 24 hr culture. Experiments are presented to exclude artefactual fluorescent cells: interaction of TMV with some non immunoglobulin membrane components; interaction of fluorescent anti TMV antibody with the Fc receptor of B cells; the binding of TMV to cytophilic immunoglobulins. The occurrence of lymphocytes able to bind several non crossreactive antigens is suggested by three lines of evidence: the high number of antigen binding cells in unimmunized mice, presence of surface immunoglobulins on some TMV binding cells after complete capping of TMV receptors and the direct demonstration of lymphocytes binding TMV and hemocyanin at different membrane sites.

From clonal selection to immune networks: induction of silent idiotypes.

Journal Article