title: Role of the adhesion molecule CD99 in platelet-neutrophil interactions.
abstract: The interaction of platelets with neutrophils plays an important role in inflammation and thrombosis and is coordinated by multiple adhesive interactions. The adhesion molecule CD99 is a key mediator of neutrophil migration across the endothelium but whether it is involved in platelet-neutrophil adhesive interactions has not previously been addressed. We found that platelet CD99 is predominantly localized on the cell surface and is not shed following platelet activation. Blocking of either platelet or neutrophil CD99 significantly diminished neutrophil migration across surface-adherent activated platelets in a quantitatively equivalent manner. In contrast, the blocking of CD99 affected neither neutrophil adhesion to surface-adherent activated platelets nor formation of circulating platelet-neutrophil conjugates. Thus, homophilic CD99 interaction mediates neutrophil transplatelet migration but is not involved or is redundant in neutrophil adhesion to surface-adherent or circulating platelets.
authors.affiliation: Institute of Immunology, Moscow, Russia; National Hematology Research Centre, Moscow, Russia.
authors.forename: Boris K
authors.initials: BK
authors.lastname: Pliyev
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Shepelev
authors.forename: Anna V
authors.initials: AV
authors.lastname: Ivanova
mesh_terms: D000071443:12E7 Antigen; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D001792:Blood Platelets / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D002448:Cell Adhesion / Q000187:drug effects; D015815:Cell Adhesion Molecules / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D002450:Cell Communication / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D018920:Coculture Techniques; D015870:Gene Expression; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000494:pharmacology; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D015539:Platelet Activation / Q000187:drug effects
chemical_list: D000071443:12E7 Antigen; D015703:Antigens, CD; C061828:CD99 protein, human; D015815:Cell Adhesion Molecules; D007140:Immunoglobulin Fab Fragments
keywords: CD99; adhesion; neutrophil; platelet; transmigration