title: Circulating levels of platelet α-granule cytokines in trauma patients.
abstract: OBJECTIVE
  To elucidate whether platelets differentiate cytokine release following trauma, we prospectively measured three major platelet-derived cytokines in 213 trauma patients on hospital arrival.
  
  
  METHODS
  We measured plasma levels of the anti-inflammatory β-thromboglobulins (βTGs), transforming growth factor-β1 (TGFβ1) and the pro-inflammatory platelet factor 4 (PF4) cytokines. We also measured soluble glycoprotein VI (sGPVI), procoagulant platelet microparticles (PMPs) and white blood cell (WBC) counts, and evaluated in vitro platelet function in primary and secondary haemostasis by aggregometry and thromboelastometry, respectively. We evaluated associations of each cytokine by multivariate regression including injury severity score (ISS), WBC counts, sGPVI and platelet counts as explanatory variables.
  
  
  RESULTS
  Severely injured patients (ISS > 15) had higher levels of βTGs and TGFβ1 (both p < 0.01) but lower levels of PF4 (p = 0.02). GPVI and PMPs levels correlated with TGFβ1 and PF4 whereas we found no significant association between cytokine levels and measures of haemostasis. By multivariate regression, a high WBC count was associated with high levels of TGFβ1 (p = 0.01) and βTGs (p < 0.01) but with low levels of PF4 (p = 0.03).
  
  
  CONCLUSIONS
  Severely injured patients had higher levels of βTGs and TGFβ1 but lower levels of the PF4; a high WBC count predicted this anti-inflammatory profile of platelet cytokines.
authors.affiliation: Department of Anaesthesia, Centre of Head and Orthopaedics, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark, nis.windelov@gmail.com.
authors.forename: N A
authors.initials: NA
authors.lastname: Windeløv
authors.forename: S R
authors.initials: SR
authors.lastname: Ostrowski
authors.forename: P I
authors.initials: PI
authors.lastname: Johansson
authors.forename: M
authors.initials: M
authors.lastname: Wanscher
authors.forename: C F
authors.initials: CF
authors.lastname: Larsen
authors.forename: A M
authors.initials: AM
authors.lastname: Sørensen
authors.forename: L S
authors.initials: LS
authors.lastname: Rasmussen
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D010978:Platelet Factor 4 / Q000097:blood*; D010980:Platelet Membrane Glycoproteins / Q000378:metabolism; D012044:Regression Analysis; D012189:Retrospective Studies; D012720:Severity of Illness Index; D053773:Transforming Growth Factor beta1 / Q000097:blood*; D014947:Wounds and Injuries / Q000097:blood* / Q000473:pathology; D001620:beta-Thromboglobulin / Q000378:metabolism*
chemical_list: D010980:Platelet Membrane Glycoproteins; D053773:Transforming Growth Factor beta1; D001620:beta-Thromboglobulin; C098341:platelet membrane glycoprotein VI; D010978:Platelet Factor 4