Lysosomal elastase and cathepsin G in beige mice. Neutrophils of beige (Chediak-Higashi) mice selectively lack lysosomal elastase and cathepsin G.

Abstract

A profound decrease in activities of the two lysosomal serine proteinases, elastase, and cathepsin G, was found in neutrophils of four independent beige mutants. Elastase and cathepsin G activities were assayed with the specific synthetic substrates MeO-Suc-Ala-Ala-Pro-Val-MCA and Suc-Ala-Ala-Pro-Phe-pNA, respectively. The defect is intrinsic to cells of beige mice, since transplantation of bone marrow from normal to mutant mice restored normal proteinase activity, and normal mice transplanted with beige marrow produced neutrophils with a deficiency of proteinase activity. The loss of elastase and cathepsin G activity was confirmed by separation of [3H]diisopropylfluorophosphate-labeled proteins on denaturing gels, which also revealed that other serine proteinases are at normal levels in beige neutrophil extracts. The deficiency of lysosomal proteinase activity appears specific, in that four other common neutrophil lysosomal enzymes, plus the spectrum of major neutrophil proteins are not affected by the beige mutation. The deficiency of proteinase activity is likely not the primary genetic alteration of the beige mutation, since more than one proteinase is affected, and heterozygous F1 mice have normal rather than intermediate levels of both proteinases. The lowered proteinase activity may contribute to the high susceptibility of beige mice and Chediak-Higashi patients to infection.

Microbicidal/cytotoxic proteins of neutrophils are deficient in two disorders: Chediak-Higashi syndrome and "specific" granule deficiency.

“…2). More recent studies in beige mnice, using specific enzymatic substrates, determined that both elastase and cathepsin t enzymatic activities were deficient (13). In this study, we observed the same type of dual deficiency in human CHS PMN, and were able to show by Western blotting for elastase and cathepsin G that the enzymatic deficiency paralleled a deficiency of the respective immunoreactive proteins.…”

Passive transfer studies with type II collagen antibody in b10.D2/old and new line and C57b1/6 normal and beige (chediak‐higashi) strains: evidence of important roles for C5 and multiple inflammatory cell types in the development of erosive arthritis

“…As reviewed by Weissmann et a1 (12), C5a will not only stimulate chemotaxis, but will also induce inflammatory cells to release proinflammatory mediators and degradative enzymes. The resistance seen in B6 beige mice may reflect this dual role of C5a, since neutrophils in these mice are not only chemotactically defective (7), but degradative enzymes, cathepsin G and elastase, are absent (13).…”

Regulation of Innate Immune Response toCandida albicansInfections by αMβ2-Pra1p Interaction

“…To compare WT and ⌬␣ M PMN degranulation in response to C. albicans, the level of intracellular ␤-glucuronidase retained in PMNs granules upon activation was determined by modification of described methods (57,93). C. albicans ( 10 7 ) of either CAI-12 or ⌬Pra1 strains were allowed to germinate overnight in 1 ml of RPMI 1640 medium; 10 6 peritoneal or peripheral blood PMNs, either WT or ⌬␣ M derived, were then added in 0.5 ml of HBSS-HEPES (pH 7.4) containing 2 mM CaCl 2 and 2 mM MgCl 2 , followed by incubation at 37°C in 5% CO 2 for 30 min.…”