Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0024312 (lymphopenia)
 4,859 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Murine graft versus host (GVH) disease takes two forms depending upon the parental/F1 strain combination employed. Acute lethal GVH disease is characterized by anemia, lymphopenia, hypogammaglobulinemia, profound anti-F1 cytotoxicity, and the loss of cytotoxic potential against third-party alloantigen. In contrast to this, chronic GVH disease is characterized by polyclonal B cell activation, autoantibody production, no anti-F1 cytotoxicity, and retained cytotoxicity against allotargets. We have previously reported that this marked disparity in disease expression results from a radiosensitive host cell which protects the F1 mouse from parental anti-F1 CTX in mice undergoing CGVH disease. Using an in vitro system to induce the host protective cell, we now demonstrate that two distinct Thy-1+ cells emerge which regulate CTX against the host. One cell is of host origin, radiation sensitive, and functionally resembles a veto cell. The second regulatory cell, of parental origin, is radiation resistant and restricted in its ability to suppress anti-F1 CTX. We further demonstrate that the emergence of these cells is modulated by competitive immunoregulatory influences mediated by T contrasuppressor and I-J+ cells.
 ...
PMID:The host response in graft versus host disease. III. The in vitro induction of regulatory cells in chronic murine graft versus host disease. 763 39

We studied clinical and immunological changes of the post-transfusional syndrome like graft versus host disease (GVDH) in six patients after open heart surgery and in one patient after hepatectomy. In the patient with hepatocellular carcinoma, transcatheter arterial embolization had been previously done. All patients received homologous blood transfusion during and after surgery and erythroderma associated hyperthermia occurred approximately 10 days after operation. Patients receiving open heart surgery died on between postoperative 17th and 21st day. One patient with hepatectomy died on the 29th day after operation. Skin biopsies in all patients showed the findings of acute GVHD. The number of CD3+ and CD4+ T lymphocytes decreased at postoperative day 1, however, the number of CD3+ T lymphocyte increased in three patients after postoperative day 14. The postoperative value of interleukin-2 production was low in patients in whom the value was measured. The immunological status in host has not been clearly resolved. However, the postoperative changes of lymphocytes subsets were abnormal and IL-2 production in two patients showed low level. Therefore, it was considered that pre and postoperative measurement of cell-modiated immunity might predict the occurrence of the post-transfusional GVHD and might be one of useful examinations to prevent the disease.
 ...
PMID:[Post-transfusional syndrome like graft versus host disease]. 839 30

Sixty-three recipients of an allogeneic marrow transplant were screened for the occurrence of cytomegalovirus (CMV) infection and clinical parameters possibly predicting the development of CMV disease in a retrospective study. Blood and urine samples obtained from these patients were screened weekly after bone marrow transplantation (BMT) for the presence of CMV by polymerase chain reaction (PCR) and virus culture technique. Forty-six of the 63 patients studied were found to be CMV-positive by PCR technique in blood and urine samples at a median of 29 days after BMT. In 33 of these 46 patients, CMV could be cultured from urine samples and 16 of the 46 had culture-positive viremia. Twenty-eight of these 46 PCR-positive patients developed CMV disease. Whereas PCR assays showed an optimal negative predictive value and sensitivity for the development of CMV disease, their positive predictive value was 61% and could not be remarkably increased when culture-proven viruria (64%) and viremia (69%) were considered. Acute graft-versus-host disease (GVHD) grade 2 to 4 (P < .05), but not underlying disease, conditioning therapy, or GVHD prophylaxis, was associated with CMV infection. On day +49, a remarkable decrease (P < .001) in the lymphocyte count, as well as in the absolute number of CD4+, CD8+, and CD56+ lymphocytes, occurred only among the patients who later developed CMV disease. The decrease of all of these cell counts, but predominantly the CD4+ T cells, to less than 100/microL on day +49 after BMT showed a very high positive predictive value (100%) for the development of CMV disease in patients with PCR-proven viremia. Persisting CD4 lymphopenia after antiviral therapy was only observed in patients who finally died of CMV disease. Thus, immunophenotyping of the patients after BMT in addition to a highly sensitive virus detection assay might help to identify patients at high risk to develop CMV disease and indicate the need for additional adoptive immunotherapy.
 ...
PMID:Lymphocytopenia as an unfavorable prognostic factor in patients with cytomegalovirus infection after bone marrow transplantation. 839 13

Murine graft versus host (GVH) disease takes two forms depending on the parental/F1 strain combination employed. Acute lethal GVH disease is characterized by anemia, lymphopenia, hypogammaglobulinemia, profound anti-F1 cytotoxicity, and the loss of cytotoxic potential against third-party alloantigen. In contrast to this, chronic GVH disease is characterized by polyclonal B cell activation, auto-antibody production, no anti-F1 cytotoxicity, and retained cytotoxicity against allotargets. We now report that this marked disparity in disease expression results from a radio-sensitive host mechanism which protects the F1 mouse from parental anti-F1 cytotoxicity in mice undergoing chronic GVH disease. Cellular analysis revealed that protection in chronic GVH disease is mediated by a phenotypically complex system of genetically unrestricted radiosensitive T cells of F1 origin. These cells fail to functionally emerge in mice undergoing acute lethal GVH disease.
 ...
PMID:The host response in graft versus host disease. I. Radiosensitive T cells of host origin inhibit parental anti-F1 cytotoxicity in murine chronic graft versus host disease. 840 29

Murine graft versus host (GVH) disease takes two forms depending on the parental/F1 strain combination employed. In an accompanying paper (Singh et al., Clin. Immunol. 151, 1993) many of the clinical features of these two forms of GVH disease are described. In addition to these clinical characteristics, acute lethal GVH (ALGVH) disease is characterized by diminished natural killer cell activity, whereas chronic GVH disease is characterized by normal or increased natural killer cell activity. Previously we have reported that this marked disparity in disease expression can be attributed to radiosensitive host cells which protect the F1 mouse from parental anti-F1 cytotoxicity (CTX) in mice undergoing chronic GVH (CGVH) disease. These cells fail to functionally emerge in mice undergoing ALGVH disease. We now report that the background genome, presumably the minor lymphocyte stimulatory loci, of the donor cells determines whether these host cells emerge and thereby dictates the form of GVH disease which is induced. C57BL/6 (B6) cells (H-2b, minor lymphocyte stimulatory locus (Mls)b) and B10.D2 cells (H-2d, Mlsb) were found to induce ALGVH disease when adoptively transferred to [C57BL/6xDBA/2]F1 (B6D2) (H-2b/d, Mls-1a/b, Mls-2a/b) recipient mice. DBA/2 cells (H-2d, Mls-1a, Mls-2a) and Balb/c cells (H-2d, Mls-1a, Mls-2b) induced CGVH disease in B6D2 mice. Using Mls congenic strains we have demonstrated that donor cell reactivity against Mls-2a was necessary and sufficient to induce ALGVH disease as determined by anemia, lymphopenia, anti-F1 cytotoxicity, and loss of cytotoxicity against allogeneic targets. Such Mls-2a reactivity correlated with the impaired induction of a host protective cell capable of vetoing self-directed CTX. Failure of this host protective cell to emerge in turn correlated with donor anti-host CTX and the emergence of ALGVH disease.
 ...
PMID:The host response in graft versus host disease. II. The emergence of host protective cells is in part determined by background genomic compatibility. 840 30

Purine nucleoside analogues are a new class of drugs with activity against non-dividing lymphocytes. They should thus play a major role in the treatment of low grade lymphoid malignancies. These drugs have been shown to have strong effect in DNA synthesis on actively dividing cells, mainly through interference with DNA polymerases and ribonucleotide reductase. However, the cell cycle kinetics of low grade lymphocytic lymphomas is characterized by the presence of very low growth fractions. Hence, the action of these drugs in slowly progressing lymphoid malignancies cannot be accounted by the same mechanism observed in actively proliferating tumors and needs to be explained through activity against quiescent resting lymphocytes. Recent work has stressed the role of purine analogues in inducing programmed cell death of quiescent lymphocytes, which could be explained through the induction of accelerated DNA strand breaks. This process leads to consumption of NAD for poly(ADP-ribose) synthesis, which could induce critical depletion of ATP. As this action extends to normal resting lymphocytes deleterious effects related to their immunosuppressive action are also observed, i.e. prolonged lymphopenia predominating in T cells and especially in CD4 subset, increased frequency of opportunistic infections and perhaps increase in autoimmune complications like autoimmune hemolytic anemia. Nevertheless, beneficial effects of this immunosuppressive action have also been reported in the prevention of graft-versus-host disease, graft rejection and in some autoimmune diseases like multiple sclerosis. Work needs to be carried out to define better the mechanisms of action of these drugs on the different immunological effectors, as well as studies in animal models of transplantation and autoimmune diseases.
 ...
PMID:Adverse and beneficial immunological effects of purine nucleoside analogues. 913 60

Murine graft-versus-host (GVH) disease takes two forms depending upon the parental/F1 strain combination employed. Anemia, lymphopenia, hypogammaglobulinemia, profound anti-F1 cytotoxicity, and the loss of cytotoxic potential against third party alloantigen is seen in acute lethal GVH disease. In contrast to this, in chronic GVH disease there is polyclonal B cell activation, auto-antibody production, no anti-F1 cytotoxicity, and retained cytotoxicity against allotargets. We have previously reported that this marked disparity in disease expression results from a radiosensitive host veto cell which protects the F1 mouse from parental anti-F1 cytotoxicity in mice undergoing CGVH disease. This cell could be induced in vitro or in vivo in CGVH disease. Using an in vitro system, we now demonstrate that a CD4(+), radiation-sensitive, T cell does emerge in acute lethal GVH disease which is capable of down-regulating cytotoxicity. The cell does not appear to be a veto cell in that it attenuates cytotoxicity directed against nonself alloantigen. The function of this cell does not appear to be influenced by minor lymphocyte stimulatory gene products. We further report that, in ALGVH disease, regulation by this cell is not readily apparent due to the emergence of a CD8(+) T cell of parental (B6) origin, which opposes its action.
 ...
PMID:CD8(+), radiosensitive T cells of parental origin, oppose cells capable of down-regulating cytotoxicity in murine acute lethal graft-versus-host disease. 983 96

Fludarabine phosphate, a purine analogue currently used in the therapy of hematological malignancies, is known to cause immunosuppression and long-lasting T cell lymphopenia. In this study, the effect of fludarabine on murine graft-versus-host disease occurring after marrow transplantation across major and minor histocompatibility barriers was evaluated. Survival of (BALB/c x C57BL/6)F1 mice irradiated and transplanted across the major histocompatibility barrier with C57BL/6 spleen cells, and subsequently treated with fludarabine was significantly longer than that of the control animals (P < 0.0001). On the other hand, fludarabine had no effect on the graft-versus-host disease and survival of CBA mice transplanted by B10.BR and of BALB/c mice transplanted by B10.D2 spleen cells across the minor histocompatability barrier. The results indicate that in certain murine models, particularly a major mismatch, fludarabine has the potential to induce bilateral tolerance and stable chimerism after marrow transplantation. Bone Marrow Transplantation (2000) 25, 263-266.
 ...
PMID:The prophylactic potential of fludarabine monophosphate in graft-versus-host disease after bone marrow transplantation in murine models. 1067 97

Lymphopenia and immune deficiency are significant problems following allogeneic hematopoietic cell transplantation (HCT). It is largely assumed that delayed immune reconstruction is due to a profound decrease in thymus-dependent lymphopoiesis, especially in older patients, but apoptosis is also known to play a significant role in lymphocyte homeostasis. Peripheral T cells from patients who received HCT were studied for evidence of increased cell death. Spontaneous apoptosis was measured in CD3(+) T cells following a 24-hour incubation using 7-amino-actinomycin D in conjunction with the dual staining of cell surface antigens. Apoptosis was significantly greater among CD3(+) T cells taken from patients 19-23 days after transplantation (30.4% +/- 12.5%, P <.05), and 1 year after transplantation (9.7% +/- 2.8%, P <.05) compared with healthy controls (4.0% +/- 1.5%). Increased apoptosis occurred preferentially in HLA (human leukocyte antigen)-DR positive cells and in both CD3(+)/CD4(+) and CD3(+)/CD8(+) T-cell subsets, while CD56(+)/CD3(-) natural killer cells were relatively resistant to apoptosis. The extent of CD4(+) T-cell apoptosis was greater in patients with grade II-IV acute graft-versus-host disease (GVHD) (33. 9% +/- 11.3%) compared with grade 0-I GVHD (14.6 +/- 6.5%, P <.05). T-cell apoptosis was also greater in patients who received transplantations from HLA-mismatched donors (39.5% +/- 10.4%, P <. 05) or HLA-matched unrelated donors (32.1% +/- 11.4%, P <.05) compared with patients who received transplantations from HLA-identical siblings (19.6% +/- 6.7%). The intensity of apoptosis among CD4(+) T cells was significantly correlated with a lower CD4(+) T-cell count. Together, these observations suggest that activation of T cells in vivo, presumably by alloantigens, predisposes the cells to spontaneous apoptosis, and this phenomenon is associated with lymphopenia. Activation-induced T-cell apoptosis may contribute to delayed immune reconstitution following HCT. (Blood. 2000;95:3832-3839)
 ...
PMID:Increased apoptosis of peripheral blood T cells following allogeneic hematopoietic cell transplantation. 1084 17

Antibody-based treatment is a novel, effective management strategy for a variety of diseases. Alemtuzumab (CAMPATH) is an example of a monoclonal antibody (mAb) that was initially developed in the laboratory and has completed its journey by being approved for therapeutic use in humans. The main clinical applications of alemtuzumab include treatment of lymphoid malignancies, particularly chronic lymphocytic leukaemia (CLL) and T-cell prolymphocytic leukaemia (T-PLL) and prevention of graft versus host disease (GVHD) and graft rejection in bone marrow and solid organ transplant recipients. Alemtuzumab administration is accompanied by a characteristic first-dose reaction due to cytokine release that consists of fever, rigors, rash and, at times, dyspnea and hypotension. The most significant toxic effect is profound, prolonged lymphopenia and the subsequent increased risk of opportunistic infections; antibiotic prophylaxis is recommended for patients undergoing alemtuzumab treatment. Alemtuzumab has demonstrated clinical activity as a single agent and has an acceptable toxicity profile. It has significant therapeutic potential, especially against lymphoid malignancies.
 ...
PMID:Alemtuzumab: a novel monoclonal antibody. 1172 36


<< Previous 1 2 3 4 5 6 7 8 Next >>