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N Borregaard

Publications and source records attributed to N Borregaard.

148 records · Page 9Linked to original sources

Cytochrome b is present in neutrophils from patients with chronic granulomatous disease.

Analysis of dithionite difference spectra demonstrated that cytochrome b was present in neutrophil homogenates from a 17-year-old girl and her 25-year-old brother who had the autosomal recessive form of chronic granulomatous disease, and from an 18-year-old boy with the X-linked form of chronic granulomatous disease. These results indicate that the postulated importance of cytochrome b in the oxygen burst during phagocytosis is questionable.

Adolescent↗

Polymorphonuclear leucocyte dysfunction during short term metabolic changes from normo- to hyperglycemia in type 1 (insulin dependent) diabetic patients.

Polymorphonuclear leucocyte (PMN) ingestion of particles coated with lipopolysaccharide (LPS) from Escherichia coli was compared to other PMN functions in seven patients with insulin dependent diabetes mellitus (IDDM) during short-term controlled metabolic changes from normo- to hyperglycemia without ketoacidosis. Factors known to interfere with PMN functions were excluded. PMN ingestion of particles coated with both LPS and bovine serum albumin became reduced from normo- to hyperglycemia. PMN motility was impaired in IDDM, but did not seem to be affected by short-term changes in metabolic control. PMN metabolism did not change from normo-to hyperglycemia. Particle-uptake by diabetic PMN is impaired after short term hyperglycemia in the range normally occurring in diabetics in every-day life.

Adult↗

Reduced function of neutrophils during routine postoperative glucose infusion.

Postoperative infusion of carbohydrate solution leads to moderate fall in the serum concentration of inorganic phosphate. The possible significance of this fall for cellular function as expressed by the neutrophils was investigated in 16 patients undergoing elective cholecystectomy. On postoperative day 2 all received 1 l 10% glucose intravenously to which in eight (randomly chosen) cases 10 mmol phosphate buffer/l had been added. Blood was sampled preoperatively and before and after the infusion. The group without phosphate supplement showed the expected significant fall in serum phosphate during the glucose infusion. The phosphate supplement prevented this fall. The hypophosphatemia was associated with significant reduction of neutrophil phagocytosis, intracellular killing, consumption of oxygen and generation of superoxide during phagocytosis. No parameter expressing neutrophil function was affected in the group with phosphate supplement. The obligatory fall in serum concentration of inorganic phosphate during postoperative carbohydrate infusion was concluded to be a cause of cellular dysfunction, the clinical importance of which is unknown.

Adult↗

YKL-40, a mammalian member of the chitinase family, is a matrix protein of specific granules in human neutrophils.

YKL-40, also called human cartilage glycoprotein-39 (HC gp-39), is a member of family 18 glycosyl hydrolases. YKL-40 is secreted by chondrocytes, synovial cells, and macrophages, and recently it has been reported that YKL-40 has a role as an autoantigen in rheumatoid arthritis (RA). The function of YKL-40 is unknown, but the pattern of its expression in normal and disease states suggests that it could function in remodeling or degradation of the extracellular matrix. High levels of YKL-40 are found in synovial fluid from patients with active RA. Neutrophils are abundant in synovial fluid of patients with RA, and the cells are assumed to play a role in joint destruction in that disorder. Therefore, we examined whether neutrophils are a source of YKL-40. YKL-40 was found to colocalize and comobilize with lactoferrin (the most abundant protein of specific granules) but not with gelatinase in subcellular fractionation studies on stimulated and unstimulated neutrophils. Double-labeling immunoelectron microscopy confirmed the colocalization of YKL-40 and lactoferrin in specific granules of neutrophils. Immunohistochemistry on bone marrow cells showed that neutrophil precursors begin to synthesize YKL-40 at the myelocyte-metamyelocyte stage, the stage of maturation at which other specific granule proteins are formed. Assuming that YKL-40 has a role as an autoantigen in RA by inducing T cell-mediated autoimmune response, YKL-40 released from neutrophils in the inflamed joint could be essential for this response. In RA and other inflammatory diseases, YKL-40 released from specific granules of neutrophils may be involved in tissue remodeling or degradation.

Adipokines↗