Vacutainer tm tubes

Plasma was collected in EDTA BD Vacutainer^TM tubes (BD, 362799), whereas serum was collected in silica BD Vacutainer^TM tubes (BD, 367820) and left to clot for 15 min. Plasma and serum tubes were then centrifuged at 2000×g for 15 min. Infectious samples were then transferred to a containment level 3 facility for safe inactivation. Samples destined for RNA extraction were inactivated by the addition of 100 µL of serum or plasma to 500 µL QIAzol (Qiagen, 79306), followed by 40 s of vortexing and 5 min incubation at room temperature. Samples destined for protein analysis were inactivated by the addition of 1% (v/v) Triton X-100 (Sigma, T8787) and 1% (v/v) tributyl phosphate (Sigma, 00675), followed by 15 s of vortexing and 4 h incubation at room temperature. Heat treatment was not performed to avoid protein precipitation. All samples were then frozen at −80 °C until further processing.

Human whole blood was collected from healthy volunteers via veni-puncture into siliconized Vacutainer^TM tubes (Becton Dickinson, Le Pont de Claix, France), containing buffered sodium citrate.Blood was then treated to prepare the platelet poor plasma (PPP), serving for the coagulation assays, as described by Ben Mansour et al. [49 (link)]. The anticoagulant activity was conducted based on three assays: the activated partial thromboplastin time (aPTT), the prothrombin ratio (PR) and the thrombin time (TT). Analyses were performed using a semi-automatic line (STart^® analyzer, Diagnostica Stago, France). All samples were dissolved in physiological saline solution, and tested in triplicate.

Synovial fluids (SF) were collected from active knee PsA and age- and sex-matched patients with knee osteoarthritis (OA). Exclusion criteria for SF analysis were local intra-articular corticosteroid injection within 5 weeks before SF aspiration. SF was collected via joint aspiration in association with therapeutic arthrocentesis. Approximately 2–4 ml of SF was collected in sodium heparin-coated Vacutainer^TM tubes (Becton-Dickinson); samples contaminated with blood were discarded. Immediately after collection, samples were centrifuged at 1,000g for 15 min at 4°C, and the resulting supernatants were stored at −80°C. Plasma from PsA, psoriasis and HD subjects were collected following standard protocol and stored at −80°C. Synovial tissues were collected from Consecutive patients fulfilling the classification criteria for Psoriatic Arthritis [PsA; (55 (link))] undergoing ultrasound guided synovial minimally invasive tissue biopsy following the published protocol using a 14G needle (Precisa 1410-HS Hospital Service Spa, Italy) (56 (link)). Once collected ST specimens were fixed in 10% neutral-buffered formalin and embedded in paraffin for Immunohistochemistry (IHC) or immunofluorescence staining.