BACKGROUND: Alpha and beta-tryptase levels in serum are clinical tools for the evaluation of systemic anaphylaxis and systemic mastocytosis. Basophils and mast cells are known to produce these proteins. OBJECTIVE: The current study examines the effect of the alpha,beta-tryptase genotype on basophil tryptase levels and the type of tryptase stored in these cells. METHODS: Tryptase extracted from purified peripheral blood basophils from 20 subjects was examined by using ELISAs measuring mature and total tryptase and by using an enzymatic assay with tosyl-Gly-Pro-Lys-p-nitroanilide. Tryptase genotypes (4:0, 3:1, and 2:2 beta/alpha ratios) were assessed by using a hot-stop PCR technique with alpha,beta-tryptase-specific primers. Total alpha,beta-tryptase mRNA was measured by means of competitive RT-PCR, and ratios of alpha to beta-tryptase mRNA were measured by means of hot-stop RT-PCR. RESULTS: Tryptase in all but one of the basophil preparations was mature and enzymatically active. Tryptase quantities in basophils were less than 1% of those in tissue mast cells. Tryptase genotypes (beta/alpha) among the 20 donors were 4:0 in 7, 3:1 in 7, and 2:2 in 6. Tryptase protein and mRNA levels per basophil were not affected by the tryptase genotype. CONCLUSION: Basophils from healthy subjects contain modest amounts of mature and enzymatically active tryptase unaffected by the tryptase genotype.
BACKGROUND: Alpha and beta-tryptase levels in serum are clinical tools for the evaluation of systemic anaphylaxis and systemic mastocytosis. Basophils and mast cells are known to produce these proteins. OBJECTIVE: The current study examines the effect of the alpha,beta-tryptase genotype on basophil tryptase levels and the type of tryptase stored in these cells. METHODS: Tryptase extracted from purified peripheral blood basophils from 20 subjects was examined by using ELISAs measuring mature and total tryptase and by using an enzymatic assay with tosyl-Gly-Pro-Lys-p-nitroanilide. Tryptase genotypes (4:0, 3:1, and 2:2 beta/alpha ratios) were assessed by using a hot-stop PCR technique with alpha,beta-tryptase-specific primers. Total alpha,beta-tryptase mRNA was measured by means of competitive RT-PCR, and ratios of alpha to beta-tryptase mRNA were measured by means of hot-stop RT-PCR. RESULTS: Tryptase in all but one of the basophil preparations was mature and enzymatically active. Tryptase quantities in basophils were less than 1% of those in tissue mast cells. Tryptase genotypes (beta/alpha) among the 20 donors were 4:0 in 7, 3:1 in 7, and 2:2 in 6. Tryptase protein and mRNA levels per basophil were not affected by the tryptase genotype. CONCLUSION: Basophils from healthy subjects contain modest amounts of mature and enzymatically active tryptase unaffected by the tryptase genotype.
Authors: Stephen J Galli; Mindy Tsai; Thomas Marichal; Elena Tchougounova; Laurent L Reber; Gunnar Pejler Journal: Adv Immunol Date: 2015-02-07 Impact factor: 3.543
Authors: Peter Valent; Cem Akin; Patrizia Bonadonna; Karin Hartmann; Knut Brockow; Marek Niedoszytko; Boguslaw Nedoszytko; Frank Siebenhaar; Wolfgang R Sperr; Joanna N G Oude Elberink; Joseph H Butterfield; Ivan Alvarez-Twose; Karl Sotlar; Andreas Reiter; Hanneke C Kluin-Nelemans; Olivier Hermine; Jason Gotlib; Sigurd Broesby-Olsen; Alberto Orfao; Hans-Peter Horny; Massimo Triggiani; Michel Arock; Lawrence B Schwartz; Dean D Metcalfe Journal: J Allergy Clin Immunol Pract Date: 2019-02-05