Optimization of induction and cryopreservation methods for mouse bone marrow-derived macrophages
10.3969/j.issn.1000-4718.2025.03.024
- VernacularTitle:小鼠骨髓源性巨噬细胞诱导及冻存方法的优化
- Author:
Qiong WEI
1
;
Mengzhu ZHAO
;
Xu CHENG
;
Menghua LIU
;
Dongmei ZHANG
Author Information
1. 北京中医药大学东直门医院,北京 100700
- Publication Type:Journal Article
- Keywords:
mouse bone marrow-derived macrophages;
primary cells;
fibroblasts;
macrophage colony-stimu-lating factor
- From:
Chinese Journal of Pathophysiology
2025;41(3):611-618
- CountryChina
- Language:Chinese
-
Abstract:
AIM:To explore suitable methods for the induction and cryopreservation of mouse bone marrow-derived macrophages(BMDMs).METHODS:Mouse fibroblasts(L929 cells)were cultured under varying conditions of temperature,seeding density,and serum concentration.The concentration of macrophage colony-stimulating factor(M-CSF)in the cell supernatant was measured using ELISA to determine the optimal conditions.Mouse bone marrow cells were extracted,and a differential adherence method was employed to pre-culture the bone marrow cells for 4 h,followed by flow cytometry to assess the proportion of resident macrophages.Flow cytometry was utilized to assess the ratio of F4/80 positive cells among the suspended and adherent cells.Induction of BMDMs was conducted using L929 cell supernatant or recombinant M-CSF for 7 d,and flow cytometry was applied to evaluate the proportion of F4/80 and CD11b double-positive cells.The morphologic changes during cell induction were observed under an inverted microscope,and the phagocytic ca-pacity and inflammatory response levels of BMDMs derived from C57BL/6N and C57BL/6J mice were evaluated using neu-tral red and ELISA methods.The cells were immediately cryopreserved after extraction,and then induced after recovery,or cryopreserved after successful induction and recovered.The cell morphology was observed under an inverted micro-scope,cell viability was assessed using the CCK-8 method,and phagocytic ability was measured using the neutral red method.RESULTS:The M-CSF concentration in the supernatant from L929 cells cultured at 33℃,10%fetal bovine se-rum(FBS)for 7 d was rich.Following 4 h of pre-culture,the proportion of F4/80 positive cells in adherent cells was sig-nificantly higher than that in suspended cells(P＜0.01).After 7 d of induction with L929 cell supernatant or recombinant M-CSF,the proportions of F4/80+CD11b+cells showed no significant difference(P＞0.05).Compared with the BMDMs derived from C57BL/6J mice,those from C57BL/6N mice exhibited stronger phagocytic capacity(P＜0.01),and released lower levels of TNF-α(P＜0.01)and IL-6(P＜0.05),and higher levels of IL-1β(P＜0.05).Compared with the BMDMs that were induced after recovery from initial cryopreservation,those cryopreserved immediately after extraction and in-duced upon recovery exhibited better macrophage morphology,higher cell viability(P＜0.01),and enhanced phagocytic ability(P＜0.01).CONCLUSION:The supernatant from L929 cells cultured at 33℃,10%FBS for 7 d is rich in M-CSF,successfully inducing bone marrow cells to differentiate into mouse BMDMs.The differential adherence method for pre-culturing can eliminate resident macrophages from the original bone marrow.The phagocytic capacity and inflammato-ry response levels differ between BMDMs derived from the C57BL/6N and C57BL/6J mouse subtypes.Cryopreserving bone marrow cells immediately after extraction and subsequently inducing them upon recovery is a preferable method for BMDM cryopreservation.
