Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The mechanisms underlying induction of immune dysregulation and chronic fungal infection by a transient tumor necrosis factor alpha (TNF-alpha) deficiency remain to be defined. The objective of our studies was to determine the potential contribution of neutropenia and immature dendritic cells to the immune deviation. Administration of an anti-TNF-alpha monoclonal antibody at day 0 neutralized TNF-alpha only during the first week of a pulmonary Cryptococcus neoformans infection. Transient neutralization of TNF-alpha resulted in transient depression of interleukin-12 (IL-12), monocyte chemotactic protein 1 (MCP-1), and gamma interferon (IFN-gamma) production but permanently impaired long-term clearance of the infection from the lungs even after the levels of these cytokines increased and a vigorous inflammatory response developed. Early neutrophil recruitment was defective in the absence of TNF-alpha. However, as demonstrated by neutrophil depletion studies, this did not account for the decrease in IL-12 and IFN-gamma levels and did not play a role in establishing chronic pulmonary cryptococcal infection. Transient TNF-alpha neutralization also produced a deficiency in CD11c(+) MHC II(+) cells and IL-12 in the lymph nodes, potentially implicating a defect in mature dendritic cell trafficking. Transfer of cryptococcal antigen-pulsed immature dendritic cells into naive mice prior to intratracheal challenge resulted in the development of a nonprotective immune response to C. neoformans that was similar to that observed in anti-TNF-alpha-treated mice (increased IL-4, IL-5, and IL-10 levels, pulmonary eosinophilia, and decreased clearance). Thus, stimulation of an antifungal response by immature dendritic cells can result in an immune deviation similar to that produced by transient TNF-alpha deficiency, identifying a new mechanism by which a chronic fungal infection can occur in an immunocompetent host.
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PMID:Transient neutralization of tumor necrosis factor alpha can produce a chronic fungal infection in an immunocompetent host: potential role of immature dendritic cells. 1561 39

T-cell large granular lymphocytes (LGL) proliferations range from reactive expansions of activated T cells to T-cell leukemias and show variable clinical presentation and disease course. The vast majority of T-LGL proliferations express TCRalphabeta. Much less is known about the characteristics and pathogenesis of TCRgammadelta+ cases. We evaluated 44 patients with clonal TCRgammadelta+ T-LGL proliferations with respect to clinical data, immunophenotype and TCR gene rearrangement pattern. TCRgammadelta+ T-LGL leukemia patients had similar clinical presentations as TCRalphabeta+ T-LGL leukemia patients. Their course was indolent and 61% of patients were symptomatic. The most common clinical manifestations were chronic cytopenias - neutropenia (48%), anemia (23%), thrombocytopenia (9%), pancytopenia (2%) - and to a lesser extent splenomegaly (18%). Also multiple associated autoimmune (34%) and hematological (14%) disorders were found. Leukemic LGLs were predominantly positive for CD2, CD5, CD7, CD8, and CD57, whereas variable expression was seen for CD16, CD56, CD11b, and CD11c. The Vgamma9/Vdelta2 immunophenotype was found in 48% of cases and 43% of cases was positive for Vdelta1, reflecting the TCR-spectrum of normal TCRgammadelta+ T-cells in adult PB. Identification of the well-defined post-thymic Vdelta2-Jdelta1 selection determinant in all evaluable Vgamma9+/Vdelta2+ patients, is suggestive of common (super)antigen involvement in the pathogenesis of these TCRgammadelta+ T-LGL leukemia patients.
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PMID:TCRgammadelta+ large granular lymphocyte leukemias reflect the spectrum of normal antigen-selected TCRgammadelta+ T-cells. 1643 45

An 8-year-old castrated male Golden Retriever was evaluated for decreased appetite, lethargy, and labored breathing of 1-week duration. Bilateral pulmonary infiltrates, hepatomegaly, and splenomegaly were present. Results of a CBC revealed marked leukocytosis (62,600/microL; reference interval 4000-15,500/microL) and large numbers of atypical cells (30,700/microL) with abundant cytoplasm. There was no concurrent anemia, neutropenia, or thrombocytopenia. Morphology of the atypical cells was most consistent with a histiocytic origin. Similar cells were identified in bone marrow aspirates, and were morphologically suggestive of the macrophage variant of disseminated histiocytic sarcoma. However, flow cytometry of the abnormal circulating cells revealed CD1c, CD11c, and major histocompatibility complex (MHC) Class II expression without expression of CD11d or lymphoid markers, consistent with myeloid dendritic antigen-presenting cells. At necropsy, the splenic architecture was effaced by neoplastic histiocytes that were also infiltrating lung, liver, an abdominal lymph node, myocardium, an bone marrow. Immunohistochemistry of the splenic neoplastic cells confirmed dendritic cell origin (CD1c+, CD11c+, MHC II+, no expression of CD11d and lymphoid markers). To the authors' knowledge, this is the first report of canine dendritic cell leukemia-in this instance accompanied by marked tissue infiltration.
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PMID:Dendritic cell leukemia in a Golden Retriever. 1853 19

Hairy-cell leukemia is a chronic B-cell malignancy seen in adults. The presenting manifestations consist of splenomegaly, pancytopenia, and characteristic monocyte depletion. The presence in peripheral blood or bone marrow of hairy cells exhibiting the CD19(+) CD20(+) CD25(+) CD11c(+) phenotype establishes the diagnosis. Rarely, patients present with inaugural joint manifestations related either to the hematological malignancy or to immune dysfunction. The resulting polymorphic polyarticular symptoms may cause diagnostic wanderings. Monocytopenia is a valuable diagnostic clue. The identification of hairy cells in the joint fluid establishes the diagnosis of leukemia-related arthritis. The treatment rests on purine analogs. One of the main differential diagnoses is Felty's syndrome, which combines rheumatoid arthritis, splenomegaly, and neutropenia. Felty's syndrome is usually caused by T-cell lymphoproliferative disorders. Among 27 patients with hairy-cell leukemia managed at our institution, 1 presented with joint manifestations. We describe this case.
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PMID:Hairy-cell leukemia with inaugural joint manifestations. 1954 26

Hairy cell leukaemia (HCL) is a rare, clonal, chronic lymphoproliferative disorder commonly seen in males in the middle years of life. Pancytopaenia with moderate to massive splenomegaly is the most common clinical presentation. Diagnosis is made on detecting the lymphocytes with abundant cytoplasm which spread into hair-like processes on peripheral blood and bone marrow smears, thus giving the name, "hairy cell leukaemia". The bone marrow aspirate is frequently a dry tap. The trephine biopsy has the characteristic features of a honey comb appearance and flow cytometry is typically CD103, CD25, FMC7, CD11c, gamma or kappa light chain positive with the classic B lymphocyte markers CD19, CD20, CD79a. Purine analogues followed by granulocyte-colony stimulating factor (G-CSF) to manage the febrile neutropenia is currently the treatment of choice. A 10 year disease free survival is recorded with these management strategies. Experimental use of anti CD20 and CD22 has also shown promising results in the treatment of this disease. We report four cases of HCL diagnosed in a span of two years at the Royal Hospital, Muscat, Oman.
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PMID:Hairy Cell Leukaemia in Oman: Four cases. 2174 80


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