Effects of thrombopoietin receptor agonists on procoagulant state in patients with immune thrombocytopenia.
Thrombopoietin receptor agonists (TPO-RA) have recently been introduced for the treatment of immune thrombocytopenia (ITP), an anti-platelet-antibodies autoimmune disease. The observation of a low frequency of bleeding episodes despite their thrombocytopenia suggests the existence of a compensatory mechanism. This study aimed to evaluate the effect of TPO-RA treatment on platelet function and on the procoagulant state in ITP patients before (ITP-bR) and after responding (ITP-aR) to treatment. Plasma- and microparticle (MP)-associated procoagulant capacity from ITP patients was similar before and after responding to the TPO-RA regimen but higher than the healthy control values. High MP-associated procoagulant activity did not seem to be due to increased platelet activation, since platelet stimulation by agonists was reduced in ITP-bR and ITP-aR patients. It could be related to increased platelet apoptosis, evaluated in terms of surface phosphatidylserine (PS), observed in both ITP groups. In summary, TPO-RA treatment increased platelet count but did not ameliorate their function and did not change plasma- and MP-associated procoagulant state of ITP patient responders to this therapy.
M T
MT
Alvarez Román
I
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Fernández Bello
E G
EG
Arias-Salgado
M I
MI
Rivas Pollmar
V
V
Jiménez Yuste
M
M
Martín Salces
Nora V. Butta, Unidad de Hematología, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046, Madrid, Spain, Tel.: +34 917277000 x 42258, Fax: +34 3582211, E-mail: nora.butta@salud.madrid.org.
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NV
Butta
D000328:Adult; D000368:Aged; D017209:Apoptosis / Q000187:drug effects; D001323:Autoantibodies / Q000378:metabolism; D001565:Benzoates / Q000008:administration & dosage* / Q000009:adverse effects; D001777:Blood Coagulation / Q000187:drug effects; D001792:Blood Platelets / Q000187:drug effects* / Q000276:immunology; D055252:Cell-Derived Microparticles / Q000378:metabolism; D005260:Female; D006801:Humans; D006834:Hydrazines / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D010949:Plasma / Q000378:metabolism; D015539:Platelet Activation / Q000187:drug effects; D011446:Prospective Studies; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000188:drug therapy*; D011720:Pyrazoles / Q000008:administration & dosage* / Q000009:adverse effects; D011961:Receptors, Fc / Q000008:administration & dosage*; D053628:Receptors, Thrombopoietin / Q000819:agonists; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage* / Q000009:adverse effects; D013926:Thrombopoietin / Q000008:administration & dosage* / Q000009:adverse effects
D001323:Autoantibodies; D001565:Benzoates; D006834:Hydrazines; D011720:Pyrazoles; D011961:Receptors, Fc; D053628:Receptors, Thrombopoietin; D011993:Recombinant Fusion Proteins; D013926:Thrombopoietin; C488777:romiplostim; C520809:eltrombopag
Thrombopoietin receptor agonists; microparticle-associated procoagulant state; platelets; thrombin generation