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Flow Cytometry Analysis of Tissue Factor Expression in Human Platelets
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Coordinated release of tissue factor and tissue factor pathway inhibitor in VLBW infants

Anniina Palojärvi1, Sture Andersson, Satu Långström

  • 1Children's Hospital, University of Helsinki, and Helsinki University Central Hospital, Helsinki, Finland. anniina.palojarvi@gmail.com

Acta Paediatrica (Oslo, Norway : 1992)
|March 6, 2013
PubMed

Insights

In very low birthweight (VLBW) infants, plasma tissue factor (TF) does not correlate with thrombin generation. Despite TF pathway inhibitor (TFPI) release, a significant circulating TF pool persists, potentially causing inflammation.

Area of Science:

  • Neonatal physiology
  • Coagulation and inflammation
  • Perinatal medicine

Background:

  • Tissue factor (TF) is a key mediator linking coagulation and inflammation.
  • TF is upregulated in the alveolar compartment and circulation of very low birthweight (VLBW) infants.
  • The role of TF in systemic coagulation regulation in VLBW infants requires further investigation.

Purpose of the Study:

  • To investigate the contribution of tissue factor (TF) to the systemic regulation of coagulation in very low birthweight (VLBW) infants.
  • To assess the relationship between TF, thrombin generation markers, and TF pathway inhibitor (TFPI) in VLBW neonates.

Main Methods:

  • Plasma samples from 51 VLBW infants were analyzed during the first week of life.
  • Measurements included tissue factor (TF), total and free tissue factor pathway inhibitor (TFPIt, TFPIf), prothrombin fragment F1+2, and thrombin-antithrombin complexes (TAT).

Main Results:

  • Prothrombin fragment F1+2 and TAT levels were high at birth and decreased significantly postnatally.
  • Plasma TF levels increased postnatally, peaking on day 3, but did not correlate with F1+2 or TAT.
  • TFPI levels increased postnatally and correlated with TF, suggesting a regulatory role, though a relative excess of TF over TFPIf was observed on day 3.

Conclusions:

  • In VLBW infants, plasma TF does not directly associate with thrombin formation, partly due to TFPI release.
  • Despite TFPI, VLBW infants possess a substantial circulating TF pool with potential proinflammatory effects.
  • This highlights a complex interplay between coagulation and inflammation in VLBW neonates.
Abstract

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