摘要:

Abstract:Defensins are a family of small, variably cationic proteins which are highly abundant in the granules of mammalian phagocytes. Three defensins, HNP‐1, 2, and 3, comprise 30–50% of total protein in azurophil granules of human neutrophils. Some defensins are broadly antimicrobial, antiviral and cytotoxic, while others are chemotactic, opsonic, or may modulate hormonal responses. The defensin molecule typically consists of 29–34 amino acids with a conserved pattern of disulfide linkage among its 6 cysteines. The three‐dimensional fold of defensins forms a highly amphiphilic molecule. Microbicidal and cytotoxic properties of defensins are most likely a consequence of their ability to insert into biological membranes and to generate pores. Defensins are synthesized by phagocytes or their precursors as a 94–95 amino acid charge‐neutralized preprodefensin, an arrangement which may avoid cytotoxic injury to the phagocyte. Although defensins were recognized only recently, the existence of homologs in certain invertebrates suggests that they are ancestral components of the host def

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00339.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:A new malignant human T‐cell line‐labelled PFI‐285‐has been isolated from a boy with malignant lymphoma. Morphologically, the cells had characteristics of malignant lymphoid cells. The cells presented surface antigens as early cortical lymphocytes and proliferated non‐adherently as single cells, independent of T‐cell growth factor (IL‐2), in liquid culture. The cells had undetectable levels of receptors for IL‐2, were not clonogenic in soft agar, but did form tumors in nude mice. Their establishment and continuous growthin vitrowas dependent on the number of cells inoculated and on the growth medium used. Cytogenetic alteration, HTLV‐1 or reverse transcriptase activity were not detected. The production of known T‐cell derived lymphokines such as IL‐2, B‐cell growth factor(s), α‐interferon or granulocyte/macrophage colony stimulating or inhibiting factor(s) was not detected. The cells had 5–8% natural killer (NK)‐cell activity against NK‐cell sensitive target cells (K562) and were not sensitive for NK cells. A most unusual characteristic was the pronounced sensitivity of the cells to ascorbic acid. Concentrations down to 50 μmo

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00340.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:Pernicious anemia appears to be autoimmune in origin and is associated with immune disorders of several organ systems. We report 4 patients with pernicious anemia and immune cytopenias, an association that may sometimes pose diagnostic problems unless specifically considered. Pernicious anemia coexisted with or was closely followed by idiopathic thrombocytopenic purpura in 3 patients and by autoimmune hemolytic anemia in a 4th patient. In addition to cobalamin therapy, all patients required corticosteroids (2 also received danazol), while 1 also required splenectomy. All 4 patients were women. The 3 patients with idiopathic thrombocytopenic purpura were also blood group O and were iron‐deficient. Autoimmune cytopenias may occur in patients with treated or untreated pernicious anemia and require specific therap

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00341.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:Blast cells from 26 cases of acute myeloid leukaemia (AML) were examined, by single and “two‐colour” flow cytometry, for relationships between membrane CD11b (monoclonal antibody OKM1), CD11c (KB90) and CD14 (Leu‐M3). Increased expression of all three determinants was associated with myelomonocytic leukaemias, with their relative diagnostic value in discriminating monocytic (M4 and M5) from non‐monocytic (M1, M2 and M3) subtypes being CD14>CD11c>CD11b. However, the results also indicated, because of the heterogenous expression of CD11c in particular, and to a lesser extent CD11b, that the patterns or histograms of fluorescent staining were potentially more informative than an empirical subdivision of blasts into positive and negative sub‐populations. In addition, analysis of phenotypic correlations by simultaneous two‐colour fluorescence showed that the expression of CD11b and CD11c determinants by leukaemic myeloid blasts was highly correlated, in contrast to the expression of CD14 and CD11c which were relatively independent. Consequently, CD11c + myeloid blasts almost always co‐expressed CD11b whereas CD14 + cases of AML often comprised CD14 + CD11c + and CD14 + CD11c‐ subpopulations. It is concluded from these observations that CD11c immunophenotyping is a useful supplementary investigation, particularly in CD14‐ cases of myelomonocytic leukaemia. However, it is also apparent that the presence of membrane CD11cper seis not lineage‐specific and that the level of expression is perhaps a more

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00342.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:Ineffective erythropoiesis is an early feature of the myelodysplastic syndromes (MDS), usually accompanying an hypercellular marrow. In a previous study, concentrations of serum erythropoietin (EPO) in MDS have been shown to correlate inversely both with haemoglobin concentration and with% bone marrow erythroblasts. We have measured erythroid production using a radioisotopic technique in 20 patients with MDS. Although haemoglobin concentration shows a weak inverse relationship with serum EPO concentration there is considerable variation in EPO concentration at a given haemoglobin level. There is no correlation between serum EPO and total erythroid production, though there is a weak correlation with effective erythropoiesis. The data suggests that control mechanisms of erythropoiesis in patients with MDS are complex.

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00343.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:Bone marrow morphology in 39 symptomatic patients with myeloproliferative disorders (polycythaemia vera 15, essential thrombocythaemia 14, idiopathic myelofibrosis 9, myeloproliferative syndrome 1) and elevated platelet counts was studied before and after a median of 18 months of continuous treatment with hydroxyurea. We found a significant reduction of bone marrow fibrosis, believed to be mediated by suppression of thrombopoiesis by hydroxyurea.

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00344.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:We determined immune function parameters in 41 newly diagnosed patients with chronic lymphocytic leukaemia (CLL) and correlated these findings with the clinical data and the subsequent course of the disease. The ratio of helper to suppressor T cells (CD4/CD8), the proportion of circulating natural killer (NK) cells and the NK activity were significantly low in clinical stage B and C patients. Among patients presenting with advanced disease, those who subsequently had a more severe course, characterised mainly by frequent respiratory infections, were found to have at presentation a significantly lower CD4/CD8 ratio (× ± SEM = 0.95 ± 0.09,vs1.28 ± 0.14), a very low proportion of NK cells (4.78 ± 0.85,vs11.75 ± 2.1%) and decreased amount of γ‐globulins (0.66 ± 0.08,vs0.97 ± 0.09 g/dl), in comparison with patients with a much milder later course. These simple parameters of immune function seem to have prognostic value for patient

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00345.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:We measured the calmodulin content in platelets in 13 normal persons and in 62 patients with hematological diseases. The level of platelet calmodulin was higher in patients with idiopathic thrombocytopenic purpura (ITP), systemic lupus erythematosus, myeloproliferative disorders, acute leukemia in a recovery phase, aplastic anemia, thrombosis and hyper‐splenism as compared to the controls. Among the patients with ITP, calmodulin was lower in responders than in nonresponders and those at the initial diagnosis. We also measured the volume, life‐span and aggregation of the platelets and demonstrated a significant relationship between the calmodulin level and the platelet volume, and a negative relationship between the calmodulin level and platelet life‐span, there was no correlation between the calmodulin level and platelet aggregation. We thus conclude that platelet calmodulin is inversely correlated with platelet tur

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00346.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:We have previously shown that normal mouse serum contains two activities that increase the number of erythroid colonies obtained from murine bone marrow colony‐forming units‐erythroid (CFU‐E) cultured in the presence of saturating Epo concentrations (0.2 U/ml). These activities could be separated by gel filtration and were referred to as peak I and peak II. We report here that peak I increases the number of erythroid colonies in cultures of adult bone marrow cells depleted of cells expressing Mac‐1 antigen. On the contrary, peak II has no stimulating effect in these cultures unless Mac‐1‐positive cells are added to the culture. This synergistic effect is mediated by an activity released in the culture medium by Mac‐1

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00347.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Abstract:Iron‐related changes in peripheral blood and variations in liver and spleen iron concentrations during alternating periods of hypoxia and normoxia have been investigated in iron‐supplemented mice by chemical and histological methods. During hypoxia, packed cell volume increased from 40 to 70%. The iron content of the liver increased during the first hypoxic and the following normoxic period, while an increase in spleen iron started after the first hypoxic period. Transferrin saturation fell from about 60 to about 20% during hypoxia and normalized during normoxia. Hypoxia together with iron supplementation led to increased erythropoiesis and parenchymal iron deposition in liver. The reduction in transferrin saturation may be attributed to the effective uptake of iron by hepatocytes simultaneously with the erythropoiesis. The spleen seemed to participate in the production of red cells during hypoxia. The increase in spleen iron during normoxia can be explained by the role of the spleen in the catabolism of excess erythrocy

ISSN:0902-4441    

DOI:10.1111/j.1600-0609.1990.tb00348.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY