摘要:

SUMMARYEleven pairs of dogs exchanged at least three skin grafts within the pairs until a “white graft” occurred and serum lymphocytotoxic antibody was demonstrated. Kidneys were then exchanged within the pairs. Six of eight kidneys in untreated dogs rejected by 12 hr, two within 36 hr. Four azathioprine-treated dogs rejected at 2, 4, 12, and 44 hr. Four dogs treated with heparin before and after transplantation did not reject hyperacutely. One animal received heparin at 15 min posttransplantation, but irreversible hyperacute rejection had already begun. Five aspirin-treated recipients did not reject acutely but were oliguric. Control grafts showed red cell aggregates in dilated peritubular and glomerular capillaries as early as 5 min. Fibrin-platelet microthrombi, swollen and vacuolated endothelial cells, and damage to arterial media were also early findings. By 24 hr, vascular thrombosis and cortical necrosis were evident. Aspirin-treated dogs showed similar but less severe changes. Heparin-treated dogs had only occasional intravascular red cell microaggregates but, by 4 days, cellular rejection was evident.

ISSN:0041-1337    

出版商:OVID    

年代:1970

数据来源: OVID

摘要:

SUMMARYNormal chickens and agammaglobulinemic young chickens were sensitized to wattle homografts; they were X-irradiated and, 3-6 days later, they were heparinized, exsanguinated, and plasma-harvested. When small volumes of this plasma were injected i.p. into normal chicks, the recipients became specifically sensitized to the wattle homografts. The effectiveness of plasma from young agamaglobulinemic chickens, which are immunologically deficient except for thymus-related activities, suggests that thymus-related lymphocytes produce immunologically specific mediators which accumulate in the circulation after X-irradiation and differ from conventional immunoglobulins. Adoptive transfer of wattle homograft immunity could not be demonstrated with injections of plasma from sensitized nonirradiated or nonsensitized irradiated chickens. If confirmed, this theory implies that subcellular, immunologically specific mediators of so called cell-mediated immunities can be released into the circulation under stress such as irradiation. These mediators, which are normally cell-bound, are released following lysis of cells which produce them and/or destruction of receptor sites on cells which normally remove them from the circulation.

ISSN:0041-1337    

出版商:OVID    

年代:1970

数据来源: OVID

摘要:

SUMMARYIn the present experiments, a neoantigen on the surface of tumour cells was separated in cell-free preparations. Large plasma membranes from cells of a recently induced murine ascites lymphoma were prepared by a two-stage centrifugal procedure using zonal rotors. The membranes appeared to be relatively uncontaminated and, when injected into syngeneic hosts, as little as 50 µg of protein/mouse induced tumor resistance in more than 50% of the animals. The new antigen, expressed on the cell surface, may be virus-dependent, but it appears to be incorporated into the plasma membrane as a cellular component. The specificity of the immunogenic effect is discussed.

ISSN:0041-1337    

出版商:OVID    

年代:1970

数据来源: OVID

摘要:

SUMMARYWhen renal allografting is performed in inbred rats across a strong histocompatibility barrier, the administration of as few as 107donor strain nucleated marrow cells in a single i.v. injection to recipients at an optimal time prior to renal allotransplantation consistently produces a marked suppression of the tempo of rejection. Normal renal function is seen 7 days following allotransplantation, a time when the unmodified recipient has essentially no function. Histological evidence of rejection is diminished as well. Recipients treated in this way have persisting normal or nearly normal renal function and indefinite survival. The production of this type of specific immunological unresponsiveness is markedly influenced by the dosage of cells used and the pretreatment interval.

ISSN:0041-1337    

出版商:OVID    

年代:1970

数据来源: OVID

摘要:

SUMMARYThe mechanism of the suppression of rejection and consequent indefinite survival of renal allografts in inbred rats, produced by a single i.v. injection of donor strain marrow cells, optimal in number and time prior to allotransplantation across a strong histocompatibility barrier, was investigated. Immunological tolerance is not the mechanism involved, for (1) some morphological evidence of rejection was present in these grafts; (2) animals bearing normally functioning allografts rejected donor strain skin grafts in normal fashion; and (3) the spleen cells of these animals were capable of responding to donor antigens in a local graft-versus-host reaction of kidney. Immunological enhancement does appear to be the mechanism involved. A globulin fraction from serum, produced by bone marrow immunization of normal L rats, was capable of suppressing renal allograft rejection when passively transferred to L recipients with a LBN F1kidney. This phenomenon is not dependent upon the complement system. In addition, it can be produced in recipients previously sensitized to donor antigens.

ISSN:0041-1337    

出版商:OVID    

年代:1970

数据来源: OVID

摘要:

SUMMARYThe effect of the pretreatment of rat thymocytes with horse antirat thymocyte sera on the attachment of the thymocytes to adherent monolayers of rat peritoneal macrophages was determined. The cytophilic antibody titer thus determined correlated quantitatively with the ability of 15 of 18 sera to prolong rat skin allografts. The results are consistent with the interpretation that the immunosuppressive activity of antilymphocytic serum is related to the ability of the serum to opsonize circulating lymphocytes, thus subjecting them to phagocytosis by the host's macrophages.

ISSN:0041-1337    

出版商:OVID    

年代:1970

数据来源: OVID

ISSN:0041-1337    

出版商:OVID    

年代:1970

数据来源: OVID

ISSN:0041-1337    

出版商:OVID    

年代:1970

数据来源: OVID

ISSN:0041-1337    

出版商:OVID    

年代:1970

数据来源: OVID

ISSN:0041-1337    

出版商:OVID    

年代:1970

数据来源: OVID