Mouse bone marrow-derived MSCs were generally isolated from the tibia and femoral marrow compartments and were identified by flow cytometry as described previously.18 (link) The cells cultured in MSC culture medium (Science Cell, 7501) with 1% mesenchymal stem cell growth supplement (Science Cell,7552), 5% fetal bovine serum (Science Cell,0025) and 1% Penicillin/Streptomycin (Science Cell,0503). The cell incubator was maintained at 37°C with 5% CO2 and 95% humidity. Every 2–3 days the culture medium was changed and Trypsin-EDTA (0.25%) (Gibco, 25200056) was used for passaging.
Neutrophils were isolated from bone marrow of 4-week-old C57BL/6J mice. The femur and tibia were resected intactly and cut the two ends of the bone in a clean bench to flush the bone marrow out. After treatment with red cell lysis buffer, the neutrophils were isolated using Mouse neutrophil isolation kit (Miltenyi Biotec, 130–097-658) according to the manual. The isolated neutrophils were cultured in RPMI1640 medium supplemented with 10%FBS for future use.