title: Coordinated release of tissue factor and tissue factor pathway inhibitor in VLBW infants.
abstract: OBJECTIVE
  Tissue factor (TF), a mediator between coagulation and inflammation, is upregulated in alveolar compartment and circulation in very low birthweight (VLBW) infants. We investigated the contribution of TF to systemic regulation of coagulation in VLBW infants.
  
  
  METHODS
  We measured TF, total and free tissue factor pathway inhibitor (TFPIt, TFPIf), prothrombin fragment (F1 + 2), and thrombin-antithrombin complexes (TAT) in plasma from 51 VLBW infants during their first week of life.
  
  
  RESULTS
  F1 + 2 in cord plasma was high (1385 pmol/mL) and decreased postnatally to 17% (p = 0.002). TAT decreased from a high cord concentration to 3% postnatally (p < 0.001). Plasma TF increased and peaked on day 3, showing no correlation with F1 + 2 or TAT. TFPIt and TFPIf increased postnatally, correlating with TF (day 1 TFPIf: R = 0.595, p < 0.001, day 3 TFPIf: R = 0.582, p < 0.001). Based on the TF/TFPIf ratio, a relative excess of plasma TF over TFPIf probably prevailed on day 3.
  
  
  CONCLUSIONS
  In VLBW infants plasma TF fails to associate with thrombin formation. This is partly explained by release of TFPI. Despite TFPI, the newborn VLBW infant is subjected to a substantial circulating pool of TF with potential proinflammatory effects.
authors: Children's Hospital, University of Helsinki, and Helsinki University Central Hospital, Helsinki, Finland. anniina.palojarvi@gmail.com
authors: Anniina
authors: A
authors: Palojärvi
authors: Sture
authors: S
authors: Andersson
authors: Satu
authors: S
authors: Långström
authors: Jari
authors: J
authors: Petäjä
mesh_terms: D000990:Antithrombin III; D001777:Blood Coagulation / Q000502:physiology*; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis; D006801:Humans; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight / Q000097:blood*; D008074:Lipoproteins / Q000378:metabolism*; D010446:Peptide Fragments / Q000097:blood; D010447:Peptide Hydrolases / Q000097:blood; D011446:Prospective Studies; D011516:Prothrombin; D013925:Thromboplastin / Q000378:metabolism*
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; D008074:Lipoproteins; D010446:Peptide Fragments; C046193:antithrombin III-protease complex; C036309:fibrin fragment D; C051928:lipoprotein-associated coagulation inhibitor; C045879:prothrombin fragment 1.2; D000990:Antithrombin III; D011516:Prothrombin; D013925:Thromboplastin; D010447:Peptide Hydrolases