title: Platelet receptor expression and shedding: glycoprotein Ib-IX-V and glycoprotein VI.
abstract: Quantity, quality, and lifespan are 3 important factors in the physiology, pathology, and transfusion of human blood platelets. The aim of this review is to discuss the proteolytic regulation of key platelet-specific receptors, glycoprotein(GP)Ib and GPVI, involved in the function of platelets in hemostasis and thrombosis, and nonimmune or immune thrombocytopenia. The scope of the review encompasses the basic science of platelet receptor shedding, practical aspects related to laboratory analysis of platelet receptor expression/shedding, and clinical implications of using the proteolytic fragments as platelet-specific biomarkers in vivo in terms of platelet function and clearance. These topics can be relevant to platelet transfusion regarding both changes in platelet receptor expression occurring ex vivo during platelet storage and/or clinical use of platelets for transfusion. In this regard, quantitative analysis of platelet receptor profiles on blood samples from individuals could ultimately enable stratification of bleeding risk, discrimination between causes of thrombocytopenia due to impaired production vs enhanced clearance, and monitoring of response to treatment prior to change in platelet count.
authors.affiliation: Australian Centre for Blood Diseases, Monash University, Melbourne, Australia.
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Gardiner
authors.affiliation: Australian Centre for Blood Diseases, Monash University, Melbourne, Australia. Electronic address: rob.andrews@monash.edu.
authors.forename: Robert K
authors.initials: RK
authors.lastname: Andrews
mesh_terms: D001791:Blood Platelet Disorders / Q000175:diagnosis; D001792:Blood Platelets / Q000166:cytology* / Q000502:physiology*; D001803:Blood Transfusion / Q000379:methods; D005786:Gene Expression Regulation; D006801:Humans; D010976:Platelet Count; D019038:Platelet Glycoprotein GPIb-IX Complex / Q000378:metabolism*; D010980:Platelet Membrane Glycoproteins / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D013921:Thrombocytopenia / Q000628:therapy; D013927:Thrombosis / Q000175:diagnosis
chemical_list: D019038:Platelet Glycoprotein GPIb-IX Complex; D010980:Platelet Membrane Glycoproteins; C098341:platelet membrane glycoprotein VI
keywords: Glycoprotein Ib; Glycoprotein VI; Hemostasis; Platelets; Thrombosis