title: Modulation of cellular annexin I in human leukocytes infiltrating DTH skin reactions.
abstract: Based on our previous studies showing endogenous annexin I being depleted from migrated neutrophils (PMN) in vitro, we have tested whether the levels of this glucocorticoid-regulated protein in PMN and mononuclear cells (PBMC) were modified after adhesion to endothelial monolayers in vitro and extravasation into skin blisters in vivo. In vitro, annexin I levels were depleted more significantly (-70%) in post-adherent PMNs than in monocytes (-25%) and lymphocytes (-50%, only in the positive fraction). In vivo, a significant time-dependent increase (approximately threefold, P < 0.05) in cell-associated annexin I was measured in PBMCs recovered from the blisters, whereas no significant changes were detected in extravasated PMNs. This was associated with annexin I release in the blister fluids (approximately 35 ng/mL), whereas no detectable protein was found in matched-paired plasmas. In conclusion, we report for the first time an activation of the annexin I pathway during an ongoing experimental inflammatory response in humans, which is differently regulated between PMNs and PBMCs.
authors.affiliation: Department of Biochemical Pharmacology, The William Harvey Research Institute, London, United Kingdom. m.perretti@qmw.ac.uk
authors.forename: M
authors.initials: M
authors.lastname: Perretti
authors.forename: S K
authors.initials: SK
authors.lastname: Wheller
authors.forename: R J
authors.initials: RJ
authors.lastname: Flower
authors.forename: S
authors.initials: S
authors.lastname: Wahid
authors.forename: C
authors.initials: C
authors.lastname: Pitzalis
mesh_terms: D000328:Adult; D017305:Annexin A1 / Q000097:blood / Q000378:metabolism*; D001768:Blister / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D002448:Cell Adhesion / Q000276:immunology; D002465:Cell Movement / Q000276:immunology*; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000276:immunology* / Q000473:pathology; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000378:metabolism*; D012867:Skin / Q000276:immunology* / Q000473:pathology
chemical_list: D017305:Annexin A1