2.1. Mice and reagents
Approval for animal study was obtained from the animal ethics committee of Erciyes University. The Balb/c mice were housed under specific pathogen-free conditions. Six groups of mice were created. These groups were (1) control, (2) Vit D, (3) MTX, (4) IL-22, (5) MTX + Vit D and (6) MTX + IL-22. Vit D was diluted in sunflower oil, thus, sunflower oil was given to controls as vehicle. Daily weight loss was checked and recorded. On Day 4th of MTX treatment, mice were sacrificed. After euthanization, brain, spleen, blood, poop, kidney, liver, esophagus, stomach, ~1cm piece from intestine, jejunum, ileum, proximal and distal colon were taken. Mice lymphocytes from lymph nodes and spleen were isolated. The serum of the blood was separated by a centrifugation at 6000 g for 10 min.