[EngO5] English Session5

[EngO5-3] Circulating activated protein C levels in septic patients treated with recombinant human soluble thrombomodulin

Takuro Arishima¹, Takashi Ito^1,2, Tomotsugu Yasuda¹, Nozomi Yashima³, Chinatsu Kamikokuryo³, Hiroaki Furubeppu¹, Takahiro Futatsuki¹, Hiroyuki Haraura¹, Ikuro Maruyama², Yasuyuki Kakihana^1,3 (1.Emergency and Critical Care Center, Kagoshima University Hospital, Japan, 2.Systems Biology in Thromboregulation, Kagoshima University Graduate School of Medical and Dental Sciences, Japan, 3.Emergency and Intensive Care Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Japan)

Background: Recombinant thrombomodulin (rTM) mainly exerts its anticoagulant effects through an activated protein C (APC)-dependent mechanism, but the circulating APC levels after rTM treatment have not been clarified.
Objectives: This prospective observational study investigated plasma APC levels after rTM treatment.
Methods: Plasma levels of soluble thrombomodulin, thrombin-antithrombin complex (TAT), protein C, and APC were measured in eight septic patients treated with rTM.
Results: rTM significantly increased thrombin-mediated APC generation in vitro. In septic patients, soluble thrombomodulin levels were significantly increased during a 30–60-min period of rTM treatment and TAT levels were decreased. However, APC activity was not increased during the treatment period.
Conclusions: Plasma APC activity is not increased in septic patients treated with rTM. It is possible that APC acts locally and does not circulate systemically.