Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We present a patient with myelodysplastic syndromes (MDS) whose neutrophils exhibited defective expression of complement receptor type 1 (CR1). A 73-year-old man was admitted with an evolution of MDS from RA into RAEBT according to the FAB classification of MDS. The neutrophil alkaline phosphatase (NAP) score was zero. The surface expression of membrane effector molecules on neutrophils was determined by indirect immunofluorescence using flow cytometry and monoclonal antibodies. The expression of CR1 on neutrophils as identified by staining with CD35 was defective in the patient, and the expression of other complement receptors (CR3 and CR4), Fc receptors and adhesion molecules was normal. CR1 deficiency and defective NAP score on neutrophils in the patient might account for impairment of common storage pool, presumably novel intracellular secretory vesicles.
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PMID:Complement receptor type 1 (CR1) deficiency on neutrophils in myelodysplastic syndrome. 780 93

Infections, an important determining factor in the clinical course of myelodysplastic syndromes (MDS), result in activation of myelomonocytic cells. In this study we demonstrate activation-associated immunophenotypic changes of cell surface antigens on monocytes and granulocytes observed in two groups of MDS patients, one with low and another one with high clinical risk, and compared them to healthy individuals. Significantly changed expression of the complement receptors 1 (CD35) and 3 (CD11b), the Fc gamma receptor I (CD64), the leucocyte-homing receptor (CD44) and the activation associated membrane proteins CD67 and M5 were found on monocytes and/or granulocytes of MDS patients. In low-risk MDS patients we observed activation-associated phenotypic changes only in monocytes, whereas in high-risk MDS patients, both monocytes and granulocytes showed such changes. Additionally, we performed respiratory burst experiments and observed an impaired response of monocytes and granulocytes derived from MDS patients. Despite the fact that all patients were free of infection by clinical criteria, cell surface phenotyping as well as the reduced respiratory burst capacity of myelomonocytic cells suggests in vivo preactivation of these cells.
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PMID:Immunophenotypic characterization of myelomonocytic cells in patients with myelodysplastic syndrome. 810 71

CD43, a sialylated glycoprotein expressed on the surface of most hematopoietic cells, has been implicated in cell adhesion and signaling. The reduced expression of this antigen in patients with Wiscott-Aldrich syndrome, in which progressive immunodeficiency is a major problem, raised the question whether abnormal expression of this molecule could affect the susceptibility to infections in patients with myelodysplastic syndromes (MDS). We studied the expression of this antigen on the monocytes of ten patients with chronic myelomonocytic leukemia (CMML) and compared the results with 67 patients suffering from other MDS syndromes and with 18 healthy individuals. We chose this series as it plays an important role in MDS patients where in most cases the neutrophils are defective. We also examined the following antigens as indicative of activation and adhesion of the monocytes in these patients: CD11b, CD18, CD35, CD38, CD44, CD69. We found decreased expression of CD43 on the monocytes of the RA, RAS, RAEB, and RAEB-t patients compared with the CMML and controls. The other activation molecules studied were found to be upregulated, suggesting the existence of activated monocytes in these patients. The increased levels of soluble vascular cell adhesion molecule in these patients suggest vascular endothelial activation in the absence of infection. Further experiments are needed to investigate the significance of CD43 downregulation in these patients, its role in cell adherence and tissue migration, and the correlation of the phenomenon to the increased susceptibility to infections observed in these patients.
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PMID:Aberrant expression of the major sialoglycoprotein (CD43) on the monocytes of patients with myelodysplastic syndromes. 1083 7

CD43 (also known as leukosialin and sialophorin) is a surface sialoglycoprotein expressed at high levels on most leukocytes implicated in adhesion, antiadhesion, and activation/proliferation mechanisms. We studied the expression of this molecule on the leukocytes of patients with myelodysplastic syndromes (MDSs) in an effort to detect acquired deficiencies of this molecule. We used immunofluorescence flow cytometry in analyzing whole blood and isolated neutrophils from 49 MDS patients, 33 men and 16 women aged 33 to 85 years (median, 75 years), and 18 healthy individuals aged 35 to 80 years (median, 72 years). According to French-American-British classification criteria, 13 patients had refractory anemia, 18 had refractory anemia with ringed sideroblasts, 9 had refractory anemia with excess of blasts, 4 had refractory anemia with excess of blasts in transformation to acute leukemia, and 5 had chronic myelomonocytic leukemia. We found decreased expression of CD43 on the neutrophils of these patients, and we correlated this finding with the activation status of these cells as it is defined by their phenotypes. We studied the expression of CD11b, CD18, CD35, CD67, CD69, CD44, and CD53 molecules known to be changed in the activated form of neutrophils. CD43 expression correlated positively with CD53 and CD44 expression and negatively with CD11b, CD18, CD35, CD67, and CD69 expression. Additionally, increased levels of soluble vascular cell adhesion molecules were detected in these patients, suggesting endothelial cell activation. In conclusion, we believe that the decreased expression of CD43 on the neutrophils of MDS patients is associated with activation of these cells and is probably due to cleavage of the molecule from the cell surface and that the same mechanism is possibly responsible for the parallel down-regulation of CD44 and CD53.
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PMID:Reduced CD43 expression on the neutrophils of MDS patients correlates with an activated phenotype of these cells. 1150 63

Flow cytometry studies of surface markers of neutrophils have been performed mostly on peripheral blood, and for a limited spectrum of diseases. Studying maturation defects on developing neutrophils in the bone marrow (BM) may be helpful in BM diseases, such as myelodysplastic syndromes and Shwachman-Diamond syndrome. We applied an expanded panel of antibodies to examine normal maturation patterns in 26 control samples of BM together with microscopic correlation. Promyelocytes correlated well with the CD24(-) and CD11b(-) populations, and metamyelocytes correlated well with the CD16(+) population (intermediate positivity). An excellent correlation was also identified between the sum of bands and segmented neutrophils and each of the following: CD16(++) (strong positivity), CD35(+), CD87(+), and CD64(-). Although visually identified segmented neutrophils paralleled CD10 positivity, there was an appreciable difference between both methods. We conclude that neutrophilic granulocyte maturation in the BM is accompanied by a change in surface antigens that reflects certain stages of development. A successful strategy for detecting maturation defects is to include several antibodies that are known to be expressed or absent at the same stage of maturation, such as CD16, CD35, CD64, and CD87.
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PMID:Flow cytometric study of neutrophilic granulopoiesis in normal bone marrow using an expanded panel of antibodies: correlation with morphologic assessments. 1473 May 56

Erythroid dysplasia is a common feature of myelodysplastic syndromes (MDS). Currently available information about the immunophenotypic features of normal and dysplastic erythropoiesis is scarce and restricted to relatively few markers. Here we studied the expression of CD117, CD35 and CD44 throughout the normal (n=16) and dysplastic (n=48) bone marrow erythroid maturation. CD35 emerged as an early marker of CD34(+) erythroid-committed precursors, which is expressed before CD105 and remains positive thereafter. MDS patients (with and without morphologic dyserythropoiesis) displayed overall increased expression of CD44, associated with slight alterations on CD35 expression, suggesting that phenotypic alterations in MDS may precede morphologic dysplasia. In turn, MDS patients with anemia showed increased expression of CD117.
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PMID:Expression of CD44 and CD35 during normal and myelodysplastic erythropoiesis. 2558 85