1. The antigenicity of homologous cortical and cancellous bone has been investigated in eighty-four rabbits. 2. The primary immune responses which occur in lymph nodes draining homografts of fresh tissues (Burwell and Gowland 1961, 1962) have been used as a histological indicator of the antigenicity of fresh homologous cortical bone freed from soft tissues. 3. The secondary immune responses which occur in lymph nodes draining homografts of fresh marrow-containing iliac bone (Burwell 1962 4. It is found that whereas fresh homologous cortical bone fails usually to produce cytological evidence of a primary response in the regional lymph nodes, fresh homologous cortical bone chips inserted into the drainage areas of lymph nodes sensitised previously to donor ..tissue evoke constantly cytological evidence of a secondary response. 5. Fresh homologous marrow-free iliac bone inserted into the drainage areas of lymph nodes sensitised previously to donor tissue does not produce detectable evidence of a secondary response. 6. Homografts of boiled marrow-containing iliac bone do not elicit a secondary response in lymph nodes previously sensitised to donor tissue. 7. Previous work has shown that homografts of frozen (–20 degrees Centigrade) marrow-containing iliac bone do not evoke a primary response in lymph nodes draining such grafts. In the present work it is shown that similar frozen homografts inserted into the drainage areas of lymph nodes previously sensitised to donor tissue evoked a secondary response in three of six lymph nodes. 8. Homografts offreeze-dried marrow-containing iliac bone fail usually to evoke a secondary response in lymph nodes sensitised to donor tissue. 9. Homografts of marrow-containing iliac bone treated by immersion in merthiolate solution before being inserted into the drainage areas of lymph nodes previously sensitised to tissue from the donor elicited a secondary response in three of five lymph nodes. 10. Knowledge concerning the antigenicity offresh and treated homologous bone is discussed in the light of recent work.
1. The antigenicity of cancellous bone has been investigated in ninety-seven rabbits. 2. The immune responses of lymph nodes draining fresh homografts of cancellous bone (Burwell and Gowland 1961 3. The principal antigenic component of a fresh homograft of iliac cancellous bone is the nucleated cells of the red marrow. 4. Homologous marrow-free cancellous bone does not usually produce cytological evidence of an immune response in the lymph node draining the graft, unless new homograft bone formation occurs. 5. The treatment of marrow-containing cancellous bone by boiling, freezing at - 20 degrees Centigrade, freeze-drying, irradiation or by merthiolate solution impairs the transplantation antigenicity of the tissue as a homograft. 6. The immersion of cancellous bone in a glycerol-serum-Ringer solution which is then slowly cooled to - 79 degrees Centigrade, stored for one week and then rapidly thawed, allows considerable preservation of the antigenicity of the red marrow. 7. Knowledge concerning the antigenicity of fresh and treated homologous bone is discussed. 8. Evidence is presented to show that the large and medium lymphoid cell response of lymph nodes draining homografts is due principally to the T-antigens, rather than H-antigens, of the grafts. 9. The changes which occur in the first regional lymph nodes draining tissue homografts may provide another test system to assess the transplantation antigenicity of foreign tissues or extracts of foreign tissues other than bone.
1. The effects of the insertion of pieces of fresh cancellous bone into the subcutaneous tissues of the ear upon lymph nodes and spleens have been investigated in seventy rabbits. 2. The main immunological response is found to occur in the first regional nodes draining the sites of insertion of homografts of bone, which show a considerable increase in weight compared with nodes draining autografts of bone. 3. An increased number of large and medium lymphoid cells occurs principally in the first regional node of the homografted animals, as Scothorne and McGregor (1955) observed using skin as the homografted tissue. 4. The large and medium lymphoid cell response is found in both the cortex and the medulla of the lymph nodes. In the cortex a sectoral distribution of the cellular response is observed and the name reactive cortex is given to these sectors. Evidence is presented to show that the sectoral pattern of reactivity is probably determined by the localised entry into the node of iso-antigens through lymphatic vessels draining the bed of the graft. 5. We have made a quantitative analysis of the large and medium lymphoid cell response in the reactive parts of the diffuse lymphoid tissue of the cortex. The mean maximal large and medium lymphoid cell response occurs five days after the insertion of bone homografts. 6. The origin and fate of the large and medium lymphoid cells and their role in the production of antibodies is reviewed in the light of recent work. 7. A correlation is made between the maximal production of large and medium lymphoid cells in the first regional lymph node, the invasion of the graft bed with small lymphocytes and the inhibition of new bone formation in the homografts.
1. An immunological examination of the sera of thirty rabbits which had received primary and secondary homografts of cancellous bone into a subcutaneous site did not reveal the presence of circulating precipitins, haemagglutinins or passive haemagglutinins. These findings are consistent with the observations of Bonfiglio and his colleagues (1955). 2. Electrophoretic examination of the serum of four rabbits receiving primary and secondary homografts of bone into an intramuscular site did not reveal any change in the serum protein fractions. 3. A search for auto-antibodies produced by primary and secondary autografts of cancellous bone was unsuccessful in fifteen rabbits. 4. The multiple injections of saline extracts of bone into four rabbits did not evoke the production of demonstrable circulating antibodies, results which are in accord with the findings of Bonfiglio and colleagues (1955) and Curtiss and colleagues (1959). 5. For the first time the production of classical antibodies in response to injections of extracts of heterologous bone has been recorded. The repeated injections of a saline extract of rabbit bone intraperitoneally into ten mice produced demonstrable precipitins and passive haemagglutinins both to protein and polysaccharide fractions present in the bone extracts. 6. Knowledge concerning the production of humoral antibodies to transplants and extracts of bone has been reviewed.
