Body weight, hind-paw volume and arthritis score were determined
weekly in all the studied groups. On day 28 post-induction,
animals were anaesthetized by an intramuscular injection of
ketamine (90 mg/kg; Merial, Lyon, France) and xylazine (10 mg/kg;
Bayer HealthCare, Kiel, Germany), and peritoneal macrophages,
as immune cells involved in the systemic inflammation, and the
spleen, as immune cell storage and secondary lymphoid tissue,
were obtained. Spleen fragments were immediately frozen at
−80 ◦C until analysis.