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)

Natural suppressor (NS) cells are capable of suppressing immunological responses in a nonspecific manner. Previously, we have described NS cells in the spleens of mice undergoing chronic graft-versus-host disease (GVHD) and also in normal B10.D2 bone marrow (BM). NS cells obtained from these environments appear dependent upon lymphokines for their ability to manifest suppression. In this report, with anti-IFN-gamma antibody, we show that IFN-gamma is necessary for NS cell activation. Anti-IFN-gamma antibody is able to remove the ability of NS cells to suppress a concanavalin A (Con A) proliferation assay. Also, anti-IFN-gamma antibody removes the ability of rIL-2, lectin-free Con A supernate (CAS), and recombinant IFN-gamma (rIFN-gamma) to enhance NS suppression of lipopolysaccharide response. By these criteria, IFN-gamma is required for NS cell activation, and rIL-2 may act indirectly by its ability to stimulate IFN-gamma synthesis. These results are discussed in the context of the immuno-suppression seen in human BM transplantation.
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PMID:Evidence that IFN-gamma is responsible for natural suppressor activity in GVHD spleen and normal bone marrow. 296 35

T cell phenotypes after bone marrow transplantation (BMT) were investigated using monoclonal antibodies (moAbs) reactive to lymphocyte cell surface antigens. Patients' T cells showed decreased percentages of OKT4, 4A and 9.3-positive T cells, and increased percentages of OKT8, human Ia, and Leu-7-positive T cells. These changes in T cell phenotype persisted for a long period after BMT and had no correlation with the occurrence of graft-versus-host disease (GVHD). No lymphocyte activation antigens such as TIA (Tac) or transferrin receptor (5E9) were detected after BMT. The capacity of the patients' lymphocytes to produce gamma-interferon (IFN-gamma) was measured after incubation of lymphocytes with mitogen. Patients' lymphocytes produced significantly lower levels of IFN-gamma than the normal controls. This failure of IFN-gamma production showed no correlation with stimulation index of mitogen blastogenesis or changes of T cell population. Thus, not only T cell phenotype but also measurement of IFN-gamma production of lymphocyte may be useful in detecting immunological abnormalities in patients who receive BMT.
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PMID:Gamma-interferon production capacity and T lymphocyte subpopulation after allogeneic bone marrow transplantation. 308 47

Immunosuppression is a well-characterized consequence of chronic graft-versus-host disease (GVHD). We have previously shown that interferon (IFN) is produced in high levels during acute GVHD. Our objective in this study was to determine if IFN, as a cytokine with known immunosuppressive qualities, could be detected in mice experiencing chronic GVHD-induced immunosuppression. Two different experimental models were used to induce chronic GVHD. The first model involved the injection of parental strain spleen cells into adult F1 hybrids (AJ----B6AF1), while the second model utilized GVHD induced across minor histocompatibility barriers (B10.D2----BALB/c). Results indicated that significant levels of serum IFN-alpha/beta are present in mice undergoing chronic GVHD. Spleen cells from chronic GVHD mice were also shown to produce significant levels of IFN-alpha/beta upon in vitro culture in medium only. This IFN-alpha/beta production was greatly increased when GVHD spleen cells were cultured with either concanavalin A (Con A) or IL-2. In contrast, IFN-gamma production was undetectable in these Con A- or IL-2-containing cultures. Additionally, these same spleen cells which produced high levels of IFN-alpha/beta were immunosuppressed as measured by mitogen-induced cell proliferation. These results suggest that IFN-gamma production is defective in GVHD spleen cells, and that the presence of high IFN-alpha/beta production by GVHD mice may contribute to the immunosuppression associated with chronic GVHD.
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PMID:Enhanced interferon-alpha/beta (IFN-alpha/beta) and defective IFN-gamma production in chronic graft versus host disease: a potential mechanism for immunosuppression. 311 28

Irradiated CBA/J mice transplanted with H-2 compatible, minor histocompatibility disparate B10.BR bone marrow develop graft-versus-host disease (GVHD) if mature T lymphocytes are added to the marrow inoculum. In the setting of mild GVHD (receiving 10(4) or 10(5) T cells), by phenotypic analysis, lymphoid reconstitution occurs normally within 4 to 6 wk but there is a profound deficiency in the ability of splenic lymphocytes to respond to polyclonal activators such as LPS and Con A. This unresponsiveness is attributable to active suppression mediated by cells that express Thy-1 and can be removed with leucine methyl ester treatment. Thus, splenocytes from mice with GVHD suppress responses of normal T and B lymphocytes. Moreover, depletion of these suppressor cells restores normal function to splenocytes from mice with GVHD, and B cells isolated from these mice respond normally to T-dependent and -independent stimulation. Finally, IFN-gamma plays an important role in this suppression, because a neutralizing anti-IFN-gamma mAb significantly removes suppression of normal cells and restores functional responses of lymphocytes from mice with GVHD. These results provide insights into the mechanisms of immunodeficiency associated with GVHD, and suggest novel strategies for possible therapies for this disorder.
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PMID:Immunodeficiency in graft-versus-host disease. I. Mechanism of immune suppression. 312 5

We have shown previously that high levels of IFN-beta were generated in vitro from spleen cells obtained from mice experiencing graft vs host disease (GVHD). However, very little or no IFN-gamma was found in these cultures even when IL-2 or Con A was added as a stimulant of IFN-gamma production. This study was undertaken to determine if the IFNs were similarly produced in vivo during the GVH reaction and to further explore the inability of GVHD spleen cells to produce IFN-gamma in vitro. GVHD was induced across minor histocompatibilities by the i.v. injection of B10.D2 spleen cells into sub-lethally irradiated BALB/c mice. Using cytoplasmic immunofluorescence to detect IFN-beta and -gamma, both IFNs were readily detectable in vivo in spleens of mice undergoing GVHD. IFN-gamma demonstrated a distinct distribution pattern, localizing in the peri-arteriolar lymphoid regions of the spleen, whereas IFN-beta immunofluorescence appeared diffusely in all areas. Expression of both IFN-beta and -gamma was shown to be dependent on the GVH reaction, inasmuch as syngeneic controls and mice given T cell-depleted donor cells had little immunofluorescence. These results contradict in vitro data in that IFN-gamma cannot be found in GVHD spleen cell cultures even in the presence of Con A. This in vitro unresponsiveness appeared to be due to the mixing of different cell populations as a result of preparing splenic single-cell suspensions. Percoll gradient fractionation of GVH spleen cells yielded a cell population which, when stimulated with Con A, produced IFN-gamma and underwent cell proliferation. This study represents the first description of the in vivo splenic distributions of IFN-beta and -gamma during GVHD, and presents data that suggest that in vitro results may not truly reflect in vivo immune responsiveness. Thus, the IFNs may play a critical role in the complex events leading to the GVHD syndrome.
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PMID:In vivo and in vitro production of IFN-beta and IFN-gamma during graft vs host disease. 314 98

Recombinant human gamma interferon (r-IFN-gamma) induces the synthesis and expression of HLA-DR antigen on cultured, normal, human keratinocytes depleted of Langerhans cells. After removal of r-IFN-gamma from the culture medium of keratinocytes that are expressing HLA-DR antigen, the cells continue to express this antigen for at least 2 days. r-IFN-gamma induces, in a dose dependent fashion, the synthesis of several triton-soluble proteins with the most prominent having an apparent molecular weight of 53,000. Whereas normal keratinocytes do not express HLA-DR antigen in vivo, they do express HLA-DR in a variety of skin diseases such as lichen planus, graft-versus-host disease, and mycosis fungoides. We propose that an understanding of lymphocyte-keratinocyte interactions in vivo may be achieved by further studies of the mechanism of action of r-IFN-gamma on cultured keratinocytes and that the results may provide insight into the patho-physiology leading to a number of common inflammatory and neoplastic skin diseases.
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PMID:Induction of the synthesis of triton-soluble proteins in human keratinocytes by gamma interferon. 392 29

Human dendritic cells (DC) generated from CD34+ hematopoietic progenitors cultured in the presence of granulocyte macrophage colony stimulating factor (GM-CSF) and tumor necrosis factor (TNF)-alpha are related to Langerhans cells (DLC) and have been shown to induce a strong proliferation of allogeneic CD4+ T cells. The present study shows that recombinant human IL-10 (h-IL-10) inhibits the primary and secondary proliferative responses of both CD4+ and CD8+ T cells induced by allogeneic CD1a+ DLC. The alloreaction induced by DLC generated after 5-18 days of culture of CD34+ HPC was equally inhibited by h-IL-10, thus indicating that DLC were sensitive to h-IL-10 at all stages of differentiation. This is further indicated by the h-IL-10-induced inhibition of the T cell alloreaction mediated by interdigitating DC freshly isolated from tonsils. h-IL-10 specifically acted on DLC as it did not affect the proliferation induced by Epstein-Barr virus lymphoblastoid cell lines (EBV-LCL) nor that induced by immobilized anti-CD3. The inhibitory effect of h-IL-10 was not due to the production of suppressive factors by the DLC, as the addition of DLC and IL-10 did not inhibit EBV-LCL-induced T cell proliferation. Rather, the inhibition of cytokine production (IL-2, GM-CSF, TNF, IFN-gamma) observed after 24 h of co-culture may explain the inhibition of T cell DNA synthesis detected 3 days later. The h-IL-10-induced inhibition of human DC mediated alloreaction advocates considering the use of h-IL-10 in the prevention of transplant rejection and graft versus host disease, phenomena initiated by DC.
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PMID:Interleukin 10 inhibits T cell alloreaction induced by human dendritic cells. 752 90

Acute and chronic graft-versus-host disease (GVHD) in the parent-into-F1 model are mediated by predominantly cellular or humoral immune responses, respectively, and are strikingly different entities by 2 wk of disease. Both forms of GVHD, however, evolve from a common starting point, i.e., donor CD4+ T cell recognition of host alloantigen and IL-2 production. Our study examines the first 2 wk of GVHD to delineate the events that critically influence GVHD development. Surprisingly, both forms of GVHD are initially characterized by increased Th2 cytokine (IL-4 and IL-10) production and B cell activation which persists into wk 2. The earliest distinguishing features of acute GVHD were detectable at days 5 through 7 of disease and consisted of 1) expansion of donor CD8+ T cells, and 2) increased IFN-gamma production by donor CD4+ and CD8+ T cells. Interestingly, IFN-gamma production by donor CD4+ T cells was not seen if donor CD8+ T cells were not engrafted in comparable numbers. Chronic GVHD in the DBA-into-BDF1 model was found to be caused by a relative defect in the ability of DBA CD8+ T cells to induce acute GVHD and to produce IFN-gamma. These studies demonstrate that both acute and chronic GVHD begin as a Th2 cytokine-mediated, B cell stimulatory response. The transition to acute GVHD is critically dependent on the engraftment of donor CD8+ T cells, which terminate B cell hyperactivity by 1) eliminating activated B cells and 2) promoting IFN-gamma secretion by donor CD4+ T cells.
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PMID:Kinetics of Th1 and Th2 cytokine production during the early course of acute and chronic murine graft-versus-host disease. Regulatory role of donor CD8+ T cells. 765 Mar 73

Although many cytokines have been previously implicated in graft-versus-host disease (GVHD), no study to date has comprehensively evaluated their expression over time or in different tissues affected by GVHD. Using a semi-quantitative reverse transcriptase-PCR technique and a murine model of acute GVHD, we have evaluated the expression levels of mRNA for a wide range of cytokines in spleen, gut and liver tissues at weekly intervals after bone marrow transfer. The earliest cytokine responses seen were increases in IL-2, IL-10, IFN-gamma, MIP-1 alpha and TNF-alpha in the spleen, suggesting a primarily Th1 pathway. Other cytokines (IL-1 alpha, IL-10 and MIP-1 alpha) were persistently elevated in GVHD mice, but were variable depending on the tissue. These data demonstrate that a wide range of cytokines are involved in the GVHD response and that their kinetic pattern of expression is different in various affected tissues.
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PMID:Kinetic and organ-specific patterns of cytokine expression in acute graft-versus-host disease. 765 87

In a fully MHC plus multiple minor antigen-mismatched murine bone marrow transplantation (BMT) model, we have demonstrated that a short course of high dose IL-2, begun on the day of BMT, protects against graft-versus-host disease (GVHD). This inhibitory effect is directed against donor CD4+ cells. To determine whether the mechanism of IL-2-induced GVHD protection involves clonal deletion or anergy of host-reactive donor T helper cells (Th), we performed limiting dilution analyses to measure the frequency of activated Th that reacted to donor, host, and third-party antigens in GVHD control and IL-2-protected mice. Marked and specific expansion of host-reactive Th was observed to a similar extent in GVHD control and IL-2-protected mice by day 5 after BMT, and the number of these cells in the spleen increased by several orders of magnitude between days 3 and 5 after BMT, which suggests that recirculation from other tissues occurred in this period. A high proportion (approximately 80%) of donor T cells expressed CD25 in both GVHD control and IL-2-protected mice on day 4 after BMT, which suggests a high level of bystander T cell activation. Since marked quantitative differences in the GVH response were not observed between GVHD control and IL-2-protected mice, we assessed both groups for qualitative differences in the Th response. Spleen cells isolated in the first 8 days after BMT were cultured with host-type, donor-type, or third-party stimulators or without stimulators, and cytokines were measured in supernatants harvested at 24 hr. GVHD was associated with marked increases in supernatant IFN-gamma levels from day 3 to day 6 after BMT, and with increases in IL-2 levels compared with naive A/J controls or syngeneic BMT controls stimulated with host antigens. Production of these cytokines was specifically induced by host-type antigens. Supernatants from spleens of IL-2-treated mice showed delayed kinetics of IFN-gamma production, and tended to contain higher levels of IL-4 in response to host antigen compared with GVHD controls on days 2 and 4 after BMT. Both IL-4 and IFN-gamma were produced almost exclusively by CD4+ cells in spleens of GVHD control and IL-2-protected mice on day 4. However, no consistent difference was observed between the groups in supernatant IL-2 or IL-10 levels, ruling out a simple Th1 to Th2 switch.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Inhibition of graft-versus-host disease by interleukin-2 treatment is associated with altered cytokine production by expanded graft-versus-host-reactive CD4+ helper cells. 767 98


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