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)

A 79-year-old woman of Mediterranean ascent suffered from corticosteroid-dependent chronic obstructive lung disease, hypogammaglobulinemia (IgG 1 and 2), decreased CD16 natural killer cell function and non-HIV related CD4 and CD8 lymphopenia. Such immunodeficiency could be either a variant of common variable immunodeficiency or an early stage of the idiopathic CD4 + T lymphocytopenia syndrome. She developed bilateral lesions of Kaposi's sarcoma on the lower extremities resembling the classic European type of the disease. The tumors contained both CD34 + and Factor XIIIa + cells. The HLA-DR5 haplotype was not found. Weekly low intravenous dosages of vinblastine improved the lesions but the patient died from pontic infarction.
 ...
PMID:[Kaposi's disease in a female patient with acquired HIV-negative immunodeficiency]. 783 Dec 65

Fludarabine phosphate selectively eliminates normal and malignant mononuclear cells in large animals and man through the inhibition of DNA synthesis. The drug depletes mononuclear cells from culture within 24 hours of initial exposure, CD4 and CD8 T cells being more sensitive than either CD20 B cells or CD34 bone marrow precursors. Mitogenic activation of lymphocytes enhances cellular elimination from culture. Fludarabine inhibits PHA-induced T-cell proliferation by >90 per cent and mixed lymphocyte reactions (allogeneic and xenogeneic) by >95 per cent. Fludarabine exerts its cytolytic effects through the induction of endonuclease-independent apoptosis. A 5-day course of fludarabine (50 mg/m2 intravenously once daily) induces both T- and B-cell lymphopenia in Cynomolgus monkeys and Papio baboons. Transient neutropenia was the only side-effect seen in experimental animals. Pretreatment of Cynomolgus monkeys with this regimen of fludarabine causes a prolongation of ABO-compatible skin allograft survival from 8 days (control) to 16 days (drug treated group). Secondary allotransplantation into presensitized recipients showed a similar prolongation of graft survival with fludarabine pretreatment (8 days vs 5 days control). Fludarabine promises to be a potent immunosuppressive agent with low clinical toxicity.
 ...
PMID:Fludarabine phosphate: A DNA synthesis inhibitor with potent immunosuppressive activity and minimal clinical toxicity. 865 23

A 75-year-old woman presenting with myelodysplastic syndrome showed cyclic oscillations in her white blood cell and platelet counts. Each cycle lasted for 5 to 6 months, with 4 cycles occurring over the course of a 2-year period. During successive cycles, the white blood cell count fluctuated from 10.1 to 2.6; 13.8 to 1.8; 11.0 to 1.6, and 8.6 to 1.3 x 10(9)/L. The platelet count fluctuated from 242 to 38, 199 to 11, 110 to 5, and 75 to 3 x 10(9)/L. The patient underwent red blood cell transfusions because of red blood cell aplasia; the frequency of the transfusions and the erythropoietin concentration in serum were inversely correlated. The number of circulating granulocyte-macrophage colony-forming units and CD34-positive cells in peripheral blood oscillated in phase with the white blood cell and platelet counts. These patterns suggested a periodic influx of progenitor cells from hematopoietic stem cells. The ratio of neutrophils to mononuclear cells remained essentially constant throughout the clinical course. Lymphocyte subset assessments using monoclonal antibodies showed an inverse CD4/CD8 ratio (less than 1) and extreme B cell lymphopenia throughout the fourth cycle. The percentage of CD3-positive cells oscillated inversely, suggesting that the cyclic cytopenia had an immune mechanism involving T lymphocytes.
 ...
PMID:Adult onset cyclic hematopoiesis in a patient with myelodysplastic syndrome. 1072 92

We studied 57 childhood acute lymphoblastic leukaemia (ALL) patients who remained in continuous complete remission after treatment according to the Dutch Childhood Leukaemia Study Group ALL-8 protocols. The patients were monitored at 18 time points during and after treatment [640 bone marrow (BM) and 600 blood samples] by use of cytomorphology and immunophenotyping for the expression of TdT, CD34, CD10 and CD19. Additionally, 60 BM follow-up samples from six patients were subjected to clonality assessment via heteroduplex polymerase chain reaction (PCR) analysis of immunoglobulin VH-JH gene rearrangements. We observed substantial expansions of normal precursor B cells in regenerating BM not only after maintenance therapy but also during treatment. At the end of the 2-week intervals after consolidation and reinduction treatment, B-cell-lineage regeneration was observed in BM with a large fraction of immature CD34+/TdT+ B cells. In contrast, in regenerating BM after cessation of maintenance treatment, the more mature CD19+/CD10+ B cells were significantly increased, but the fraction of immature CD34+/TdT+ B cells was essentially smaller. Blood samples showed a profound B-cell lymphopenia during treatment followed by a rapid normalization of blood B cells after treatment, with a substantial CD10+ fraction (10-30%). Heteroduplex PCR analysis confirmed the polyclonal origin of the expanded precursor B cells in regenerating BM. This information regarding the regeneration of BM is essential for the correct interpretation of minimal residual disease studies.
 ...
PMID:Regenerating normal B-cell precursors during and after treatment of acute lymphoblastic leukaemia: implications for monitoring of minimal residual disease. 1093 Sep 91

By flow cytometry (FC) and an extensive panel of markers we characterized leukemia cells from the peripheral blood (PB) and bone marrow (BM) of 13 symptomatic patients with hairy cell leukemia (HCL). Hairy cells (HCs) identified in the large cell gate always expressed B-cell markers - CD19, CD20, CD22, HLA-DR, and 'HCL-restricted' markers - CD22+CD11c, CD25 and CD103. Other markers, not followed regularly, were occasionally expressed, such as CD34, CD38, CD71, CD15, CD10 and kappa/lambda light chains. Furthermore, in one patient with suspect but not proved HCL in PB or BM, neither morphologically nor immunologically, we confirmed the diagnosis of HCL. Only the immunophenotyping of splenic cells after splenectomy confirmed HCL diagnosis. Flow cytometry was repeated at 3-5 month intervals, after treatment with 2-Chlorodeoxyadenosine (CdA) or less frequently alpha-interferon (IFN). We investigated serially lymphocyte subsets after treatment and we found profound and persistent CD4+ lymphopenia in majority of studied patients after CdA treatment. Simultaneously we investigated the value of FC to detect minimal residual disease (MRD) and to establish, whether MRD+ could predict relapse. Detection of MRD in our series predicted hematological relapse only in one case with persistent MRD+, in majority of cases with occasionally found MRD+ phenotype, did not. Using quantitative immunophenotyping we observed significantly higher values of molecule numbers of hairy cell B-cell markers, comparing to B-cells in nonleukemic gate of the same sample. Our study showed 1) the diagnostic value of FC in management of HCL patients, 2) long-lasting response in the majority of patients after CdA, 3) a profound and persistent CD4+ lymphopenia in CdA treated patients, 4) some correlation between persistent MRD staining and hematological relapse, and 5) further, till now not described activated feature of HCs, given by the increased values of molecular numbers (molecules of equivalent soluble fluoresceine - MESF) in B-cell antigens of HCL.
 ...
PMID:Flow cytometry of peripheral blood and bone marrow cells from patients with hairy cell leukemia: phenotype of hairy cells, lymphocyte subsets and detection of minimal residual disease after treatment. 1184 78

The incidence of postengraftment invasive aspergillosis (IA) in hematopoietic stem cell transplant (HSCT) recipients increased during the 1990s. We determined risks for IA and outcomes among 1682 patients who received HSCTs between January 1993 and December 1998. Risk factors included host variables (age, underlying disease), transplant variables (stem cell source), and late complications (acute and chronic graft-versus-host disease [GVHD], receipt of corticosteroids, secondary neutropenia, cytomegalovirus [CMV] disease, and respiratory virus infection). We identified risk factors associated with IA early after transplantation (<or= 40 days) and after engraftment (41-180 days). Older patient age was associated with an increased risk during both periods. Chronic myelogenous leukemia (CML) in chronic phase was associated with low risk for early IA compared with other hematologic malignancies, aplastic anemia, and myelodysplastic syndrome. Multiple myeloma was associated with an increased risk for postengraftment IA. Use of human leukocyte antigen (HLA)-matched related (MR) peripheral blood stem cells conferred protection against early IA compared with use of MR bone marrow, but use of cord blood increased the risk of IA early after transplantation. Factors that increased risks for IA after engraftment included receipt of T cell-depleted or CD34-selected stem cell products, receipt of corticosteroids, neutropenia, lymphopenia, GVHD, CMV disease, and respiratory virus infections. Very late IA (> 6 months after transplantation) was associated with chronic GVHD and CMV disease. These results emphasize the postengraftment timing of IA; risk factor analyses verify previously recognized risk factors (GVHD, receipt of corticosteroids, and neutropenia) and uncover the roles of lymphopenia and viral infections in increasing the incidence of postengraftment IA in the 1990s.
 ...
PMID:Invasive aspergillosis in allogeneic stem cell transplant recipients: changes in epidemiology and risk factors. 1239 25

The period of immunodeficiency following autologous hematopoietic stem cell transplantation is characterized by transient expansions of CD8+CD45RO+CD57+ T lymphocytes, displaying markers of an activated phenotype. Most evidence suggests that this early reconstitution results from proliferation of mature T cells that have survived conditioning or were transferred with the graft. Although homeostatic mechanisms are thought to act in maintaining total T-cell numbers, the degree to which antigen-driven expansions contribute and the nature of the stimulating antigens remain unclear. CD34 selection of stem cell grafts reduces the available T-cell pool, potentially delaying immune reconstitution and resulting in increased infective complications. In the allogeneic transplantation setting, lymphopenia has been associated with cytomegalovirus (CMV) infection risk and, if persistent, with adverse outcome. We prospectively studied patients undergoing CD34-selected (n = 13) or unselected (n = 13) autologous hematopoeitic stem cell transplantation for immune reconstitution and CMV infection. No significant differences were demonstrated between graft types with respect to lymphocyte subset recovery, T-cell receptor beta-chain variable region spectratype diversity, or CMV DNA detection rates (45% versus 40%). CMV infection was associated with a trend toward higher rather than lower CD8+ counts at 6 weeks posttransplantation (P =.08) that became significant by 3 months (P=.007), and that was associated with decreased T-cell receptor beta-chain variable region spectratype diversity (P =.01). CMV-specific HLA-tetramer analysis demonstrated transient expansions with CDR3 lengths corresponding to those of some of the major posttransplantation T-cell expansions demonstrated by spectratype analysis suggesting that CMV-specific T cells contribute to the pattern of immune reconstitution.
 ...
PMID:Reconstitution of T-cell repertoire after autologous stem cell transplantation: influence of CD34 selection and cytomegalovirus infection. 1265 71

IL-7 is a critical component of thymopoiesis in animals and has recently been shown to play an important role in T cell homeostasis. Although there is increasing interest in the use of IL-7 for the treatment of lymphopenia caused by the HIV type 1, evidence that IL-7 may accelerate HIV replication has raised concerns regarding its use in this setting. We sought to identify the effects of IL-7 on human thymocyte survival and to determine the impact of IL-7 administration on in vivo HIV infection of the human thymus. Using in vitro analysis, we show that IL-7 provides potent anti-apoptotic and proliferative signals to early thymocyte progenitors. Analysis of CD34(+) subpopulations demonstrates that surface IL-7 receptor is expressed on most CD34(high)CD5(+)CD1a(-) thymocytes and that this subpopulation appears to be one of the earliest maturation stages responsive to the effects of IL-7. Thus, IL-7 provides survival signals to human thymocytes before surface expression of CD1a. CD4(+)CD8(+) thymocytes are relatively unresponsive to IL-7, although IL-7 protects these cells from dexamethasone-induced apoptosis. IL-7 has a predominantly proliferative effect on mature CD4(+)CD3(+)CD8(-) and CD8(+)CD3(+)CD4(-) thymocytes. In contrast to the in vitro findings, we observe that in vivo administration of IL-7 to SCID-hu Thy/Liv mice does not appear to enhance thymocyte survival nor does it appear to accelerate HIV infection. Given the growing interest in the use of IL-7 for the treatment of human immunodeficiency, these findings support additional investigation into its in vivo effects on thymopoiesis and HIV infection.
 ...
PMID:Effects of IL-7 on early human thymocyte progenitor cells in vitro and in SCID-hu Thy/Liv mice. 1284 29

Dendritic cells (DCs) can be utilized either as vectors or as targets for therapy. Patients with metastatic melanoma received CD34-DC vaccine that contains Langerhans' cells and interstitial DCs. DCs were pulsed with MART1, tyrosinase, MAGE3, gp100 and Flu-MP peptides, and KLH. DCs induced an immune response to control antigens in 16/18 patients. An enhanced immune response to 1 or more melanoma antigens (MelAgs) was seen in these 16 patients. The two patients failing to respond experienced rapid tumour progression. Six out of seven patients with immunity to two or fewer MelAgs had progressive disease 10 weeks after study entry, in contrast to tumour progression in only 1/10 patients with immunity to > two MelAgs. Since tumour immunotherapy targets autologous antigens we can learn from systemic autoimmunity such as systemic lupus erythematosus (SLE). As opposed to normal monocytes, SLE monocytes induce proliferation of allogeneic CD4+ T cells. SLE sera induce monocyte differentiation towards DCs in an IFNalpha-dependent mechanism. Spiking autologous serum with IFNalpha reproduces DC differentiation. 50% of SLE patients have high serum levels of IFNalpha, which could explain T/B lymphopenia. Yet, plasmacytoid DCs, a major IFNalpha source, are 80% decreased. pDCs and IFNalpha may play a role in SLE pathogenesis and therapy.
 ...
PMID:Dendritic cells: controllers of the immune system and a new promise for immunotherapy. 1460 22

To ascertain the consequences of severe leukopenia and the tempo of recovery, we studied the immunity of 56 adult patients treated for multiple sclerosis or systemic sclerosis with autologous CD34 cell transplantation using extremely lymphoablative conditioning. NK cell, monocyte, and neutrophil counts recovered to normal by 1 month; dendritic cell and B cell counts by 6 months; and T cell counts by 2 years posttransplant, although CD4 T cell counts remained borderline low. Initial peripheral expansion was robust for CD8 T cells but only moderate for CD4 T cells. Subsequent thymopoiesis was slow, especially in older patients. Importantly, levels of antibodies, including autoantibodies, did not drop substantially. Infections were frequent during the first 6 months, when all immune cells were deficient, and surprisingly rare (0.21 per patient year) at 7-24 months posttransplant, when only T cells (particularly CD4 T cells) were deficient. In conclusion, peripheral expansion of CD8 but not CD4 T cells is highly efficient. Prolonged CD4 lymphopenia is associated with relatively few infections, possibly due to antibodies produced by persisting pretransplant plasma cells.
 ...
PMID:Recovery from and consequences of severe iatrogenic lymphopenia (induced to treat autoimmune diseases). 1550 94


1 2 Next >>