Gene/Protein Disease Symptom Drug Enzyme Compound
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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)

Complement-mediated lysis of (subsets of) T lymphocytes in bone marrow grafts is increasingly used to prevent acute graft-versus-host disease in human bone marrow transplant recipients, especially in case of major immunogenetic disparity between donor and recipient. Since T lymphocyte depletion has resulted in an increased frequency of allogeneic engraftment failures, its effect on hemopoietic reconstitution was measured in rhesus monkeys. The reactivity patterns of commonly used types of antihuman T lymphocyte monoclonal antibodies (MCAs) with rhesus monkey lymphocytes was analyzed using a double-label cytofluorometry technique and found to be very similar to those with human lymphocytes. The antibodies investigated included CAMPATH-1 (recognizing an antigen present on virtually all lymphocytes and monocytes), OKT4 + 4a (CD4, helper/inducer T lymphocytes), B9 (CD8, suppressor/cytotoxic T lymphocytes), WT-1 (CD7, pan-T), and anti-DR MCAs as stem cell toxic controls. Their possible toxicity to hemopoietic stem cells was studied by using a semiquantitative autologous regeneration assay. Cytotoxic lysis of cells in the bone marrow grafts reacting with the T lymphocyte purging MCAs did not result in delayed regeneration compared to untreated autologous grafts. It is concluded that T lymphocyte depletion using anti-T-lymphocyte MCAs does not influence the repopulating capacity of an autologous bone marrow graft.
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PMID:The repopulation capacity of bone marrow grafts following pretreatment with monoclonal antibodies against T lymphocytes in rhesus monkeys. 327 19

Immunohistological and morphometric techniques were used to study the skin after marrow transplantation with particular reference to the relationship of marrow purging, the presence of a clinical rash and histological changes to leucocyte numbers and phenotype. Recipients of T-cell-depleted marrow showed significant reductions in CD2+, CD4+ and CD8+ T-lymphocytes in the first 22 d after transplantation but not after this time. T-cell numbers in recipients of unpurged marrow were similar to those of normal donors, indicating a rapid repopulation by cells from the graft. Langerhans cells (CD1+ dendritic cells) and macrophages, on the other hand, were present in similar numbers in both groups of patients within the first 22 d; the former in low and the latter in normal numbers. Biopsies exhibiting graft versus host disease showed increases in CD2+, CD4+ and CD8+ T-lymphocytes with significant lowering of the CD4:CD8 ratio. A proportion expressed markers of activation and HNK1+ cells and macrophages were also increased. Biopsies exhibiting epidermal basal abnormalities only (changes identical to graft versus host disease but without detectable leucocyte infiltration on conventional microscopy) showed a minor increase in macrophages and HNK1+ cells but no other leucocyte alterations to suggest a pathogenetic link with graft versus host disease. Langerhans cells were reduced in these biopsies, however, when taken more than 22 d post-transplant, suggesting that the epidermal changes are associated with Langerhans cell damage or repopulation. We were unable to identify any significant alteration in leucocytes in patients with strong clinical evidence of graft versus host disease but with histologically unremarkable biopsies. Although it is possible that perivascular increases in T-cells and expression of activation markers precede the characteristic histological picture of graft versus host disease the time scale is probably too short to allow diagnostic value.
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PMID:Cutaneous leucocyte composition after human allogeneic bone marrow transplantation: relationship to marrow purging, histology and clinical rash. 328 67

The cellular composition of the spleen has been assessed in 18 patients who died 15-326 days after receiving allogeneic marrow for leukaemia. The white pulp showed marked lymphocyte depletion with no germinal centres, very few B cells, and rare plasma cells. The marginal zone was unrecognizable but there were moderate numbers of T cells in the periarteriolar lymphatic sheaths (PALS), showing great variation in CD4/CD8 ratio. The percentage of CD4+ cells decreased with time post transplant. CD8+ cells were reduced in patients with graft-versus-host disease (GvHD) who also showed no increase in cells staining for activation markers. No T cells were detected expressing immature phenotypes and no differences were detected between patients who received marrow purged or unpurged of T cells. Macrophage numbers appeared normal. Extramedullary haemopoiesis (EMH) was predominantly in the red pulp greater than 30 days after transplantation but more commonly in the white pulp before then. Pyknotic cells were common in seven cases and appeared to be associated with EMH rather than GvHD. Chimaeric studies demonstrated small numbers of donor cells in the PALS at 26 days and larger numbers at 56 days.
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PMID:Cellular composition of the spleen after human allogeneic bone marrow transplantation. 329 36

A new pharmacologic agent, anti-CD3F(ab')2-ricin toxin A chain (RTA), was synthesized for the purpose of targeting T cells and as a means of treating established graft-versus-host disease (GVHD). The Fc region of anti-CD3 monoclonal antibody (MoAb) was removed to prevent its ability to activate T cells. The resulting F(ab')2 fragments were conjugated to deglycosylated RTA (dgRTA), a catalytic and potent phytotoxin. The resulting immunotoxin (IT) was potent (greater than 95% inhibition) and selective in inhibiting T-cell mitogenesis in vitro. In vivo, the IT depleted 80% of T cells in mice receiving bone marrow (BM) transplants. Transplantation in an aggressive acute GVHD model using C57BL/6 donor cells and H-2 disparate B10.BR recipients resulted in an infiltration of CD3-expressing cells and a median survival time (MST) of 20 to 30 days. A 5-day course of anti-CD3F(ab')2-RTA (30 micrograms/d intraperitoneally) beginning 7 days after GVHD induction was beneficial in treating established GVHD in these mice, as evidenced by significantly prolonged survival (MST, greater than 80 days), superior mean weight values, and improved clinical appearance. Neither intact anti-CD3, unconjugated anti-CD3 F(ab')2 fragments, nor a mixture of anti-CD4 and anti-CD8 MoAbs (which are highly effective in prophylactic models) were as effective. F(ab')2 fragments made from anti-Lyt-1 (the murine homologue of human anti-CD5) linked to RTA were also not effective, despite the fact that both anti-CD3F(ab')2-RTA and anti-Lyt-1F(ab')2-RTA had similar half-lives of about 9 hours. The IT also increased MST in two aggressive models of GVHD across non-H-2 minor histocompatibility barriers, indicating that the usefulness of anti-CD3F(ab')2-dgRTA is not limited to a single-strain combination. This agent should be further investigated as an alternative to current strategies for treating steroid refractory GVHD.
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PMID:Therapy for ongoing graft-versus-host disease induced across the major or minor histocompatibility barrier in mice with anti-CD3F(ab')2-ricin toxin A chain immunotoxin. 749 98

The effects of rhG-CSF on peripheral blood lymphocytes and lymphocyte populations in the apheresis product has been determined in 13 individuals (11 autografts and 2 normal donors) who had peripheral blood mononuclear cells (PBMCs) collected on days 3, 4, and 5 of administration of rhG-CSF 16 micrograms/kg/day x 5 days. The absolute number of CD34+ cells increased 9 and 25-fold from pretreatment levels after 4 and 5 days of rhG-CSF, respectively. All patients demonstrated an increase in CD3, CD4, CD8, CD19 and CD20 lymphocytes after 3 days of rhG-CSF with T lymphocytes increasing 1.5-2.0 times baseline by day 3 or rhG-CSF administration. All lymphocyte phenotypes returned to below pretreatment levels on days 4 and 5 of rhG-CSF administration. The ratio of CD4/CD8 lymphocytes was not affected by rhG-CSF. Collection of PBMCs on 3 consecutive days yielded a mean of 8.77 x 10(8) CD34 cells, 14.03 x 10(10) total nucleated cells and 3.17 x 10(10) CD3 lymphocytes. These data suggest that rhG-CSF mobilized PBMCs have approximately one log more T cells than marrow and the effect of rhG-CSF on the quantity and phenotype of lymphocytes is minimal. Strategies for coping with an increased incidence of GVHD, if it occurs, could include the utilization of both methotrexate and cyclosporine as immunoprophylaxis, selective T cell depletion or CD34 positive selection.
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PMID:Lymphocyte content in peripheral blood mononuclear cells collected after the administration of recombinant human granulocyte colony-stimulating factor. 751 58

Patients who receive bone marrow transplants from unrelated donors have a high incidence of graft-versus-host disease (GVHD). If the donor marrow is first T cell-depleted, the everity of GVHD declines but the risk of rejection rises. In an attempt to prevent both graft rejection and GVHD, we included an anti-T cell antibody-toxin conjugate (CD-5-Ricin; XomaZyme H65) in the transplant conditioning regimen. After receiving a partially T cell-depleted marrow, patients then received a second course of immunotoxin as additional GVHD prophylaxis. Eight recipients of unrelated donor marrow transplants were studied. All engrafted (ANC > 500 x 10(6)/l by day 15, range 13-20 days). One patient had grade II skin GVHD and one developed grade IV disease but the other six patients had no acute GVHD. However, there was high morbidity and mortality from virus infections associated with a sluggish return of CD4 and CD8 T cells into the normal range. Four patients died from virus disease (CMV, n = 2; EBV, n = 1; adenovirus, n = 1) and the remaining patients had frequent documented viral illnesses during the first year. We conclude that improvement in the outcome of unrelated donor marrow transplantation will require strategies which prevent rejection and GVHD coupled with attempts to accelerate immune reconstitution.
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PMID:XomaZyme-CD5 immunotoxin in conjunction with partial T cell depletion for prevention of graft rejection and graft-versus-host disease after bone marrow transplantation from matched unrelated donors. 751 37

Prevention of graft-versus-host disease by depletion of CD6-positive T cells was studied in the dog. Donors were DLA-homozygous, recipients DLA-heterozygous with one DLA haplotype identical to the donor. Seven control dogs received untreated marrow and died of GvHD after full hemopoietic recovery within 28 days of transplantation. For prevention of GvHD, immunomagnetic separation of T cells with a monoclonal antibody against human CD6 that crossreacted with canine T cells was evaluated. Depletion of CD6-positive cells depleted CD4-positive cells completely, but only part of CD8-positive cells and DR-positive cells. CD6-depleted marrow exhibited strong nonspecific "natural" suppression of the generation of cytotoxic T cells in vitro. Eleven dogs received CD6-depleted marrow. Only 1 dog developed GvHD and died. Sustained engraftment was seen in 8 dogs. Hemopoietic recovery was delayed and slower after transplantation of CD6-depleted marrow than after transplantation of untreated marrow. Four of these dogs were treated with G-CSF, and this accelerated the recovery of leukocytes, but did not prevent rejection. Chimerism was mixed in 7 of 10 evaluable dogs and 1 dog recovered its own hemopoiesis 2 years after transplantation. CD6 depletion prevents GvHD across a DLA-haplotype difference, but rejection and mixed chimerism may occur. Treatment with G-CSF accelerates leukocyte recovery, but cannot prevent rejection.
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PMID:Prevention of graft-versus-host disease in DLA-haplotype mismatched dogs and hemopoietic engraftment of CD6-depleted marrow with and without cG-CSF treatment after transplantation. 752 57

Murine GVHD across multiple minor histocompatibility barriers (B10.D2 into irradiated BALB/c) results in cell-mediated destruction of bile ducts inside the liver. Similar changes are characteristic of hepatic GVHD in humans following BMT. We have defined the phenotypes of inflammatory cells and the accessory/adhesion molecules expressed in the liver between day 7-14 of murine GVHD. T cells (CD3+) comprised 65% of hepatic inflammatory cells. alpha-beta and gamma-delta cells accounted for 92 and 8%, respectively of hepatic T cells. The percentage of CD4+ cells (29%) was 3 times that of CD8+ cells (11%). Lymphocyte function-associated antigen-1 (LFA-1) was expressed by the majority of inflammatory cells. Thirty per cent of the cells were positive for Mac-1, a differentiation marker of macrophages, large granular lymphocytes, and natural killer cells. Expression of intercellular adhesion molecule-1 and major histocompatibility complex class II (IAd) molecules on bile duct epithelial and portal vein endothelial cells was induced during GVHD. These results suggest that hepatic GVHD is induced by donor alpha-beta T cells through mechanisms that may involve CD4:1Ad and LFA-1:ICAM-1 interactions.
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PMID:Liver T cell subsets and adhesion molecules in murine graft-versus-host disease. 758 Nov 14

NK-like cytotoxicity in F1-hybrid mice with acute GVH disease is mediated by donor-derived CD3+/CD4-/CD8- cells that can lyse both NK-sensitive YAC-1 target cells as well as NK-resistant targets such as BW1100 and P815. Our objective was to determine whether this activity is mediated by gamma delta TCR+ cells. We showed that NK-like cytotoxic activity in the spleen and lymph nodes of mice with acute GVH disease could be depleted by indirect complement-mediated lysis using an Ab against gamma delta TCR. When purified NK1.1+ spleen cells that had been positively selected on a magnetic cell separator were used as effector cells, we found that NK-like cytotoxicity was mediated only by gamma delta TCR+ cells, suggesting that cells with NK-like activity are gamma delta TCR+/NK1.1+. We showed by flow cytometry experiments that coexpression of NK1.1 and TCR-gamma delta occurred on a large proportion of large granular lymphocytes in the spleens of GVH mice, but was not detectable in normal control mice. In GVH mice, fewer than 10% of small agranular NK1.1+ lymphocytes coexpressed NK1.1+ and gamma delta TCR+. On the basis of this hypothesis, we postulate that graft-derived large granular lymphocytes develop the NK1.1+/gamma delta TCR+ phenotype during the reaction, and that these cells play a role in the pathogenesis of acute GVH disease. We performed experiments to determine whether depletion of gamma delta T cells from donor mice affected the outcome of lethal GVH disease and found that there was a significant reduction in mortality.
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PMID:Gamma delta T cells in the pathobiology of murine acute graft-versus-host disease. Evidence that gamma delta T cells mediate natural killer-like cytotoxicity in the host and that elimination of these cells from donors significantly reduces mortality. 759 74

An acute graft versus host disease (GvHD) murine model was developed to study the pathogenic and protective mechanisms against viruses that replicate in cells of the human immune system. The model allowed efficient replication of lymphotropic, macrophage and amphitropic strains of human immunodeficiency virus type 1 (HIV-1) and measles virus (MV). Cytopathic lymphotropic strains of HIV-1 and a wild-type MV strain replicated in a 'burst'-like manner, whereas a non-cytopathic lymphotropic HIV-1 strain and all macrophage-tropic HIV-1 strains caused persistent infection of the graft. The replication kinetics of infection with these viruses were highly reproducible and were very similar to those observed in natural infection of humans. Infection with these viruses, with the exception of HIV-1SF2, led to a delay [corrected] and abrogation of the GvHD, indicating a direct immunosuppressive effect. Interestingly, infection with the lymphotropic HIV-1SF2 strain was rapidly and spontaneously abrogated. The model was also shown to be suitable for the evaluation of passive immunization strategies. Administration of a combination of antibodies against the HIV-1 V3 loop and the HIV-1 CD4 binding sites prevented subsequent infection with HIV-1IIIB. In contrast, administration of CD4 binding site specific human monoclonal antibody at a concentration that would neutralize the virus in vitro enhanced in vivo infection with HIV-1IIIB. The model also allowed evaluation of in vivo immunization studies. Immunization with a live attenuated measles vaccine resulted in protection from a wild-type MV challenge, whereas immunization with a subunit candidate vaccine appeared to give partial protection.
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PMID:Efficient replication of human immunodeficiency virus type 1 and measles virus in a human-to-mouse graft versus host disease model permits immunization research. 759 77


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