title: Density of platelet collagen receptors glycoprotein VI and alpha2beta1 and prior myocardial infarction in human subjects, a pilot study.
abstract: BACKGROUND
  Prior studies evaluating whether platelet collagen receptors affect risk of myocardial infarction (MI) have used common polymorphisms thought to affect receptor density, and have yielded conflicting results. Our objective in the current pilot study was to obtain preliminary information on the relationship between platelet collagen receptor density and prior MI.
  
  
  METHODS
  We measured glycoprotein VI (GPVI) and integrin alpha2beta1 density by flow cytometry using FITC-conjugated monoclonal antibodies in consecutive subjects from an outpatient cardiology practice. We used a case-control design to match 77 patients with prior MI to 77 control patients. Matching was performed on the basis of traditional risk factors for MI.
  
  
  RESULTS
  The mean GPVI density was 14% higher in those with prior MI (P = 0.098), and the alpha2beta1 density was 6% higher in those with prior MI (P = 0.49). A GPVI or alpha2beta1 density within the lowest decile was associated with a lower MI prevalence (OR = 6.3, 95% CI: 1.3-29.2 P = 0.009).
  
  
  CONCLUSIONS
  Our preliminary data suggests that platelet collagen receptor density, when measured directly, may be related to prior myocardial infarction. An appropriately sized clinical study using this methodology is warranted to further investigate whether collagen receptor density serves as a novel risk factor for myocardial infarction.
authors.affiliation: Philadelphia Veterans Affairs Medical Center, University of Pennsylvania Health System, 19104, USA.
authors.forename: Frederick F
authors.initials: FF
authors.lastname: Samaha
authors.forename: Christopher
authors.initials: C
authors.lastname: Hibbard
authors.forename: Jay
authors.initials: J
authors.lastname: Sacks
authors.forename: Hong
authors.initials: H
authors.lastname: Chen
authors.forename: Michael A
authors.initials: MA
authors.lastname: Varello
authors.forename: Thomas
authors.initials: T
authors.lastname: George
authors.forename: Mark L
authors.initials: ML
authors.lastname: Kahn
mesh_terms: D000368:Aged; D001792:Blood Platelets / Q000378:metabolism; D016022:Case-Control Studies; D005434:Flow Cytometry; D005838:Genotype; D006801:Humans; D038982:Integrin alpha2beta1 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000235:genetics / Q000276:immunology*; D010865:Pilot Projects; D010980:Platelet Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D011110:Polymorphism, Genetic; D038981:Receptors, Collagen / Q000097:blood* / Q000235:genetics
chemical_list: D038982:Integrin alpha2beta1; D010980:Platelet Membrane Glycoproteins; D038981:Receptors, Collagen; C098341:platelet membrane glycoprotein VI