摘要:

SUMMARYPortions of embryonic tail tissue transplanted before functional maturation of the host's immune system do not survive indefinitely. Small allografts of tail tissue evoke an immune response, whereas large tail transplants induce a state of tolerance. Hosts that had earlier rejected small tail transplants vigorously destroyed test skin grafts in typical second-set fashion, while hosts bearing large, viable tail allografts tolerated subsequent skin grafts from the original donors. Donor origin skin grafts were tolerated beyond metamorphosis after resorption of the tolerance-inducing tail graft. Donor leukocytes were found in the circulation of diploid juvenile frogs grafted with large triploid tail grafts. Although these observations suggest antigen sharing between lymphocytes and skin in the frog and, further, implicate donor lymphocytes as the source of persisting antigen, the role of serum factor(s) which mediate tolerance may also be important in this system

ISSN:0041-1337    

出版商:OVID    

年代:1973

数据来源: OVID

摘要:

SUMMARYThe survival of BALB/c skin allografts on CBA mice subjected to an immunosuppressive “pulse” consisting of a short combined treatment with procarbazine and antilymphocyte serum (ALS) after grafting was studied. Graft survival was modified by additionally injected donor strain thymocytes or bone marrow cells. An i.v. cell injection 6-16 days before grafting and immunosuppressive treatment was most effective. Two zones of cell dosage, particularly very small doses, caused accelerated graft rejection. A potentiation of the action of ALS was provided by procarbazine. A low, well tolerated supplement of this drug increased more than 10-fold the effect of a moderate dose of ALS. Inferior ALS-sparing effects or none at all were encountered with cyclophosphamide, cytosine arabinoside. and colchicine. Procarbazine alone, as well as the combined regimen, also effectively prolonged the survival of BALB/c heart allografts in C3H hosts. The cardiac grafts were also protected by the passive administration of antiserum. Xenograft. Survival was prolonged only slightly by the immunosuppressive pulse and impaired by prior cell injection. Spleen cells from mice carrying long standing BALB/c allografts displayed reactivity against BALB/c antigens in a graft-versus-host assay

ISSN:0041-1337    

出版商:OVID    

年代:1973

数据来源: OVID

摘要:

SUMMARYMice injected i.v. with corresponding transplantation sera (containing anti-H-2 antibodies) exhibited severe (often fatal) shocks occurring in the subsequent 20 min. Accompanied by deep hypothermia, followed by a refractory period, these shocks were immunologically specific, and the corresponding serum activity was specifically removable by target antigens. Although inhibited by aggregated human γ-globulins (HGG), this “immunoallogeneic shock” was attributed to a reverse passive anaphylactic shock for the following reasons: it was completely inhibited by Phenergan and it was consistently correlated with the anaphylactic properties of the sera utilized or their chromatographic fractions and not with their complement-fixing activity

ISSN:0041-1337    

出版商:OVID    

年代:1973

数据来源: OVID

摘要:

SUMMARYA vigorous round cell reaction, followed by destruction of the graft, ensues when C57BL/10 embryos of 8 days or more of development are grafted to adult B10.D2 hosts preimmunized with C57BL/10 tissues. Since the strains differ only at theH-2 locus, and since the cellular infiltrate does not occur when syngeneic embryo grafts are made, the reaction is taken as evidence for the expression of H-2 antigens in the 8-day embryo. Results with younger embryos suggest that H-2 first appears on the membrane around day 7 of development, since grafts of 7-day embryos provoke a strong reaction within 3 days of grafting, while most grafts of 6-day embryos do not provoke a reaction until the 3rd or 4th day after grafting

ISSN:0041-1337    

出版商:OVID    

年代:1973

数据来源: OVID

摘要:

SUMMARYThe rat popliteal lymph node graft-versus-host reaction (GVHR) has been studied for evidence of a separate host contribution similar to that seen in mouse graft-versus-host (GVH)-induced splenomegaly. Donor lymphoid cells from Lewis or Brown Norway rats were injected under the hind footpads of (Lewis X Brown Norway)F1hybrid hosts. The resulting popliteal node enlargement at 7 days depended in part upon a host contribution, which was reduced by preliminary host irradiation or cyclophosphamide treatment. When the irradiated host was reconstituted with syngeneic bone marrow cells, the node enlargement was fully restored. Furthermore, a rebound or exaggerated enlargement occurred when footpad injection was delayed until 9 days after reconstitution. The host contribution would have to be nonspecific for the following reasons. It could not be a specific immune reaction in the F1hybrid host, which is genetically incapable of reacting against the parental strain donor. It was immediately restored by syngeneic marrow cells. Its reconstitution was not accompanied by the ability to induce GVHR in appropriate normal hosts

ISSN:0041-1337    

出版商:OVID    

年代:1973

数据来源: OVID

摘要:

SUMMARYUnidirectional mixed lymphocyte culture (MLC) reactions were investigated to determine the feasibility of assessing in vitro histocompatibility in two species of marmosets. When lymph node cells from white-lipped marmosets were mixed in allogeneic or xenogeneic MLCs, there was an enhanced incorporation of14C-thymidine in comparison to autologous mixtures. Peak response was at 5 days. In contrast, cotton-top marmoset allogeneic mixtures showed weak responses with no enhanced label uptake when cultured for a period of 8 days. When blood lymphocytes were cultured in the same medium used to assay histocompatibility with lymph node cells, there was little difference between the values for MLCs and responding cells alone. This might be explained by the fact that marmoset blood is known to transform blastically and proliferate myeloid elements in vitro. Modification of the culture medium produced significant responses in xenogeneic MLCs with blood lymphocytes; however, allogeneic MLC values were not significantly different from tolerant cotwin MLC values. Lymph node MLC response with cells from a kidney graft recipient that died on day 302 postsurgery failed to show specific sensitization to donor cotwin antigens

ISSN:0041-1337    

出版商:OVID    

年代:1973

数据来源: OVID

摘要:

SUMMARYMechanisms by which specific antibodies enhance or curtail the survival of foreign grafts were investigated in strains of inbred rats characterized by a broad range of histoincompatibility barriers to orthotopic kidney grafts. The effectiveness of passive IgG recipient antidonor strain immunoblocking alloantibodies was found to increase greatly as the histoincompatibility became weaker. This IgG enhancement increased from 2-fold (Buffalo (Bu) &U279E; Lewis (Le)) to 20-fold ((Le X Bu)F1&U279E; Le) to persistent (Fischer (Fi) &U279E; Lc) prolongation of renal allograft survival. Kidney allograft rejection eventually occurred across stronger H-l (Ag-B) disparities despite continued IgG impairment of transplantation immunity, whereas non-H-1, H-X, and H-Y differences allowed enhanced kidney grafts to remain fully functional indefinitely. By contrast, purified IgM antibodies from the same high titer serums were clearly cytotoxic. causing significantly shortened kidney allograft survival in both the Bu &U279E; Le and (Le X Bu)F1&U279E; Lc combinations. IgG-treated rats with long surviving kidney allografts became neither fully tolerant nor nonspecifically suppressed. Specific suppression of transplantation immunity by the continuing presence of certain IgG alloantibodies now appears to be characteristic of the allograft-acceptant state in adult rats and mice. Several levels of specific immunoregulation or selective immunoblocking are discussed

ISSN:0041-1337    

出版商:OVID    

年代:1973

数据来源: OVID

摘要:

SUMMARYThe specific responsiveness of Lewis (Le) rats with fully functional Buffalo (Bu) or (Le X Bu)F1hybrid kidney allografts exhibiting enhanced survival following early injection of recipient antidonor strain IgG was characterized by several methods. Passive IgG given in high dosage soon after grafting was found to be completely sequestered by donor kidney antigens in diverse tissue sites within 24-48 hr, even on a repetitive basis. When acute allograft rejection across these strong H-l incompatibilities is precluded by early IgG administration, active antibody production subsequently sustains the specific immunoblocking. Specific skin transplantation immunity gradually waned in recipients with successfully enhanced kidney allografts. Thus, Bu test skin grafts show progressively increasing median survival times (MST) of 7, 13, and 40 days, respectively, when placed at 0, 40, and 100 days after renal transplantation. By contrast, control Brown Norway (BN) skin grafts all showed acute rejection with an MST of 9.9 days, regardless of the time F1kidneys had remained in residence. Direct tests of cell-mediated immunity (CMI) in vitro revealed that blood lymphocytes from Le recipients of either Bu or (Le X Bu)F1kidney allografts possessed killing activity against donor fibroblasts inversely proportional to the degree of specific immunosuppression in vivo. CMI was most depressed in long surviving F1&U279E; Le recipients treated with Le anti-Bu IgG. Local graft-versus-host (GVH) reactivity measured by popliteal lymph node weight assay was greater in recipients of Le spleen cells from long surviving F1kidney-allograftcd animals than in controls. Taken together these findings reveal that rats with long functioning renal allografts become neither tolerant overall nor nonspecifically suppressed. Rather they show IgG antibody-dependent suppression of specific CMI which increases with time and often leads to persistent allograft survival

ISSN:0041-1337    

出版商:OVID    

年代:1973

数据来源: OVID

ISSN:0041-1337    

出版商:OVID    

年代:1973

数据来源: OVID

ISSN:0041-1337    

出版商:OVID    

年代:1973

数据来源: OVID