The significance of diminished sTWEAK and P-selectin content in platelets of patients with pulmonary arterial hypertension

• Published in: Cytokine (Philadelphia, Pa.) Pa.), 2018-07, Vol.107, p.52-58
• Main Authors: Kazimierczyk, Remigiusz, Błaszczak, Piotr, Kowal, Krzysztof, Jasiewicz, Małgorzata, Knapp, Małgorzata, Szpakowicz, Anna, Ptaszyńska-Kopczyńska, Katarzyna, Sobkowicz, Bożena, Waszkiewicz, Ewa, Grzywna, Ryszard, Musial, Włodzimierz J., Kamiński, Karol A.
• Format: Article
• Language: English
• Subjects: P-selectin; Platelets; Prognosis; Pulmonary arterial hypertension; sTWEAK
• ISSN: 1043-4666; 1096-0023
• DOI: 10.1016/j.cyto.2017.11.014

•Patients with PAH present comparable serum sTWEAK concentrations as controls.•Platelet content of TWEAK and P-selectin is diminished in patients with PAH.•Lower platelet TWEAK is associated with clinical indices of more advanced disease.•Patients with lowest platelet TWEAK more frequently develop detoriation of PAH.•sTWEAK secreted by platelets may affect PAH progression and prognosis. Pulmonary arterial hypertension (PAH) is a progressive disease characterized by proliferative changes in pulmonary arteries. There is growing evidence suggesting that soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) and P-selectin could be involved in PAH development and progression. Here we investigate whether circulating platelets may be a source of sTWEAK and contribute to diminished availability of sTWEAK and P-selectin in PAH patients. We have prospectively enrolled two independent study groups of stable patients with confirmed PAH and age matched controls: derivation (10 PAH; 15 controls) and validation (20 PAH; 12 controls). P-selectin and sTWEAK concentrations were measured in platelet-poor plasma and platelet lysate. To avoid procedural bias, in each group we employed different protocols for platelet isolation. Consistently, both in derivation and validation groups PAH patients presented significantly lower sTWEAK content in platelets than control group with no significant differences in plasma levels. Similarly, patients presented comparable to controls plasma P-selectin concentrations and lower concentration in platelet lysate. Kaplan-Meier analysis revealed that patients with low platelet sTWEAK/total protein concentration ratio had more frequently detoriation of PAH in the follow-up (16.51 ± 3.32 months), log-rank test, p = .03. Patients diagnosed with pulmonary arterial hypertension present diminished sTWEAK and P-selectin storage capacity in platelets. Thrombocytes appear to be a major source of sTWEAK that could be released upon local injury and its decreased availability could have an impact on pathophysiology and prognosis in PAH.