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Query: UMLS:C0018133 (graft-versus-host disease)
 18,032 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Transplantation of cells from the bursa of Fabricius reconstitutes the B cell system of chemically bursectomized chickens. Even allogeneic bursa cells can restore the recipient's B cell system and induce tolerance to donor major histocompatibility complex antigens, but the chimeras cannot mount a T-dependent antibody response. In order to study the mechanisms of tolerance to class II MHC (B-L) antigens, we transplanted class II-incompatible bursa cells from 4-day-old donors into cyclophosphamide-treated recipients of the same age. Donor and host cells carried different allelic products of a genetically polymorphic B cell alloantigen (Bu-1), allowing us to detect cellular chimerism using monoclonal antibodies and immunofluorescence. The B cell-chimeric chickens were tested for tolerance by skin grafting, graft-versus-host splenomegaly assay, and mixed lymphocyte reaction. Specific unresponsiveness to donor MHC antigens was observed in all three tests. When spleen cells from chickens tolerant of donor class II antigens were transferred into irradiated secondary recipients of the same strain, several of the secondary recipients accepted primary donor-type skin grafts. Most secondary recipients were, however, reactive in the GVH assay and MLR. Depletion of chimeric B cells before spleen cell transfer impaired the transferability of tolerance to class II disparity. Altogether, our results indicate that tolerance to class II antigens can be induced with B cells. They suggest that at least two different mechanisms maintain the unresponsiveness in B cell-chimeric chickens.
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PMID:B cell-induced tolerance to class II MHC antigens in the chicken. 252 81

The mouse monoclonal antibody 25-3 specific for the alpha subunit of LFA-1 (CD11a) has been infused to children undergoing HLA non-identical bone marrow transplantation because of lethal inherited diseases or of leukemia in order to prevent graft failure. We have assessed the serum concentrations of the antibody infused according to two regimens: 0.1 mg/kg five times, every alternate day (eight patients) or 0.2 mg/kg daily for 10 days (30 patients). Serum trough levels of 25-3 antibody in the first group were constantly found to be low (less than 0.6 micrograms/ml) while 25-3 serum concentration in the second group rose progressively to a mean value of 2.2 micrograms/ml. Serum antibody concentrations were significantly lower in patients with greater antigenic mass, i.e. with splenomegaly, or non conditioned. The engraftment rate was slightly higher in patients treated by the daily infusion of 25-3 for 10 days. No immunization against 25-3 antibody occurred. One patient who subsequently received other mouse anti-B cell antibodies eventually produced anti-isotype antibodies. The consequences of 25-3 infusion on leukocyte counts has been evaluated in the group of patients (n = 6) with severe combined immunodeficiency who did not receive any chemotherapy and in one who was treated with 25-3 because of acute graft-versus-host disease. In none of the cases did 25-3 antibody infusion modify blood leukocyte counts. In addition, it was shown that saturation of LFA-1 on leukocytes was a transient phenomenon, since it could not be found 24 h following infusion of 25-3 antibody.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:In vivo infusion of anti LFA-1 antibody in HLA non-identical bone marrow transplantation in children: serum concentrations and biological effects. 267 57

Three strains of MHC homozygous chickens were used to study the ontogeny of the GVH-R. It was found that this function of the immune system was acquired with a delay in animals raised in germ-free conditions. In our previous work, we had shown that, contrary to expectation, bursal cells were capable of mounting a GVH-R against embryos, and actually were particularly efficient in this regard when compared to spleen cells. The present experiments have disclosed that splenomegaly induction may be dissociated from the toxic effect that bursal cells also exert on recipient embryos.
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PMID:Ontogeny of the GVH-R inducing capacity, in conventional and germ-free chickens. 276 11

Transplantation of allogeneic bursal cells into cyclophosphamide-treated, immunodeficient chickens is a useful experimental model for analyzing the mechanisms of transplantation tolerance, especially because transplanted bursal cells do not produce graft-versus-host disease. In this study we have determined B-lymphoid chimerism in various lymphoid organs after transplantation of allogeneic bursal stem cells or postbursal cells, and used a variety of tests to determine presence of immunological tolerance. Transplanted bursal stem cells induced a state of stable chimerism that could easily be detected in peripheral blood and other lymphoid organs. Chimerism induced by postbursal cells was low in peripheral blood, but clearly observable in other lymphoid organs, especially in spleen and thymus. Both bursal and postbursal cells induced specific unresponsiveness to donor-line alloantigens. Bursal cell recipients accepted donor line skin grafts--and their graft-versus-host reactivity, as assayed by embryonal splenomegaly, and mixed lymphocyte reactivity against donor line alloantigens were significantly decreased. Despite differences in chimerism, a strong transplantation tolerance was readily induced with bursal stem cells and with postbursal cells.
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PMID:Lymphoid cell chimerism and transplantation tolerance induced by bursal and postbursal cells. 293 68

Although isolated intraepithelial lymphocytes (IEL) have been shown to have specific and non-specific cytolytic functions, their ability to proliferate in response to T-cell mitogens or alloantigens is controversial. Here we show that IEL from mouse small intestine do not respond to mitogens such as concanavalin A and phytohaemagglutinin A or in mixed lymphocyte reactions unless an accessory spleen cell is also present. Adherent spleen cells possess the most potent helper function, but a dividing accessory cell may also be required. Supernatants from stimulated lymphocytes also assist IEL to proliferate in vitro, particularly in the presence of adherent accessory cells. IEL could not mediate lethal graft-versus-host disease in irradiated hosts, but could produce popliteal lymph node hypertrophy or splenomegaly in unirradiated hosts. Thus, IEL have the potential for proliferative activities characteristic of T cells, but they require accessory cells and/or factors such as interleukin-2 for their function in vitro and in vivo.
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PMID:Functional characteristics of intraepithelial lymphocytes from mouse small intestine. II. In vivo and in vitro responses of intraepithelial lymphocytes to mitogenic and allogeneic stimuli. 294 64

Implantation of either major histocompatibility complex (MHC)-disparate thymus to 7-day thymectomized (Tx) Xenopus in late larval life, or allogeneic skin to perimetamorphic controls, routinely induces tolerance towards implant-strain skin grafts applied in adult life. To characterize this allotolerance further, additional in vivo approaches were attempted. Injection of gamma-irradiated (5000 rads) implant-strain splenocytes into frogs bearing tolerant skin grafts revealed (within 3 days) significantly elevated tritiated thymidine uptake by host spleen cells, compared to siblings injected with isogeneic cells. Although this in vivo 'mixed leucocyte reaction' proved to be thymus dependent, the identity of the cells involved awaits clarification. When non-restored Tx Xenopus are injected with live MHC-disparate splenocytes, graft-versus-host (GVH)-induced mortality ensued within 2 weeks. Such GVH disease also occurred (albeit more chronically) when Tx allothymus-implanted animals were given MHC-incompatible splenocytes, but only when these came from the thymus donor strain. Splenocytes from thymus-implanted animals failed to achieve GVH-induced splenomegaly when transferred to appropriate hosts (bearing MHC antigens of the thymus donor strain). Overall, the experiments indicate that alloreactivity against donor cells is impaired but not completely inhibited in Xenopus following perimetamorphic implantation.
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PMID:In vivo studies on allotolerance perimetamorphically induced in control and thymectomized Xenopus. 296 Jun 13

The severity of the graft-versus-host (GVH) reaction, judged by splenomegaly and immunosuppression, was augmented by murine cytomegalovirus (MCMV) infection. Profound GVH-induced immunosuppression was seen in adult unirradiated MCMV-infected F1, mice even after challenge with extremely low doses of parental spleen cells. Mice receiving MCMV+GVH challenge died from days 16-21, with interstitial pneumonia being the most prominent pathological lesion. Pulmonary disease was unrelated to levels of viral replication in the lung. These results suggest that in human marrow recipients, cytomegalovirus infection may play a primary role both in provoking or accentuating GVH disease, as well as in the development of interstitial pneumonia.
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PMID:Augmentation of graft-versus-host reaction by cytomegalovirus infection resulting in interstitial pneumonitis. 298 27

We explored the immunoincompetence of mice undergoing a chronic graft-vs-host reaction (GVHR) across minor histocompatibility barriers. BALB/c and B10.D2 mice are H-2d and mls b, and differ only with regard to minor histocompatibility antigens (MiHA). A large number of BALB/c mice were unirradiated or were irradiated with 300, 600, or 900 R. They then were injected with 5 X 10(7) spleen cells from either allogeneic B10.D2 or syngeneic BALB/c mice. The spleen cells from these recipient mice were assayed at various times post-irradiation/injection for their proliferative response to Con A and LPS, their ability to suppress the mitogen responses of normal spleen cells, and for the genetic specificity of this suppression. Spleen cells from BALB/c mice that had received 600 or 900 R (but not 0 or 300 R), and allogeneic B10.D2 lymphocytes, became very hyporesponsive to mitogens and became suppressive in vitro by days 7 to 10 post-irradiation/injection. These phenomena persisted for the entire 49 days of the experiment. After an initial period of splenomegaly, the spleens of these mice gradually became depleted of viable lymphocytes. Initial characterization of suppressor cells found in the spleens of GVH mice showed that they were not removed by treatment with anti-Thy-1.2 plus complement. GVH suppressors also were not adherent to plates coated with antiserum directed towards murine Ig. In addition, these cells did not adhere to plastic plates. Thus, we believe that the suppressor cells found in mice undergoing GVHD across MiHA are not mature T cells, B cells, or macrophages, but belong to a class of suppressor cells termed natural suppressor (NS). Genetic analysis of NS cell activity showed that as early as 10 days post-irradiation/injection, NS cells inhibited mitogen responses of all mouse strains tested, the exception being the relative difficulty in suppressing the LPS response of B10.D2 (syngeneic with donor cells). By day 42, this had developed into an almost complete inability to suppress a B10.D2 LPS response, although at this time NS cells were still capable of inhibiting all the other mitogen responses of all strains tested, including the Con A response of B10.D2 spleen cells. Moderate amounts of mitogen unresponsiveness and suppressor activity were seen in the syngeneic groups (BALB/c----BALB/c) but only if recipients received 600 or 900 R. This was a transient phenomenon that was maximal at day 14, and which we believe to be a similar but less severe degree of immunoincompetence when compared with that seen with allogeneic stimulation in the B10.D2----BALB/c GVH model.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Graft-vs-host reactions (GVHR) across minor murine histocompatibility barriers. II. Development of natural suppressor cell activity. 316 Jul 74

We examined whether nude mice, which are deficient in T cell function, could be used as a model for induction of lethal graft-versus-host disease. Nude mice injected with MHC-disparate spleen cells exhibited only transient GVH reaction such as splenomegaly. Inoculation of B6 spleen cells into BALB/c nude mice produced high titers of alloantibodies to the donor cells. These alloantibodies eliminated host-MHC-reactive donor T cells from the host. After abolition by 400 rads irradiation of the capacity of nude mice to produce antibody, lethal GVHD could be induced by allogeneic spleen cell transfer and was mediated by donor T cells. This lethal GVHD was prevented by prior administration of antidonor alloantibody to the irradiated recipients at least 24 hr before donor-cell grafting. The role of alloantibody was substantiated in 2 other combinations in which little or no alloantibodies to donor spleen cells were produced. Engraftment of either MHC-identical but non-MHC disparate donor spleen cells into BALB/c nude mice or of parental spleen cells into F1 nude mice resulted in death mediated by T cells. In addition, irradiated BALB/c nude mice inoculated with non-MHC-incompatible B10.D2 spleen cells were much more sensitive to alloaggression by the donor cells than were nonirradiated hosts, indicating the presence of some radiation-sensitive component(s) acting in nude mice against GVHD induction by donor T cells. Thus the nude mouse is considered to be a useful recipient for clarifying the basic mechanisms involved in lethal GVHD.
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PMID:Lethal graft-versus-host disease in nude mice. I. Establishment of model systems. 326 65

The spleens of 49 patients who had undergone allogeneic bone marrow transplantation for leukemia were compared at autopsy to determine the pathological changes associated with graft-versus-host disease (GVHD). The only significant finding was an increase in weight of about 1.7 times that of spleens from patients without GVHD. This was not explained by differences in the patients' sex, length of survival after transplantation, presence of infection, or liver pathology. On histological examination, there was no detectable increase in congestion, siderosis, or numbers of lymphocytes, macrophages, antigen-presenting cells, blast cells, pyknotic cells, plasma cells, or hemopoietic cells to explain the increase in spleen weight. On the contrary, there was actually a reduction in CD8+ T lymphocytes. No proliferative phase of GVHD could be identified, possibly due to a lack of specimens examined less than 8 days after transplantation and to prophylactic measures undertaken to minimize GVHD. The pathogenesis of splenomegaly in human GVHD is unclear.
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PMID:Enlargement of the human spleen in graft-versus-host disease. 328 55


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