A murine distal femoral epiphysis ischemia model reveals spatiotemporal stratification of necrotic bone marrow clearance and associated inflammatory responses.

ABSTRACT:

Background

Efficient clearance of necrotic marrow is essential for repair after epiphyseal ischemia, yet the tissue-level spatiotemporal evolution of this process and its immunoregulatory mechanisms remain incompletely defined.

Methods

Using a refined juvenile ischemic osteonecrosis (JIO) model of the murine distal femoral epiphysis-with medial plus lateral approaches guided by mapped vascular entry points-we fully interrupted epiphyseal perfusion and harvested tissue at postoperative days 1-28. Coronal sections along the vascular entry axis underwent H&E/TUNEL and zonal IHC/IF (Ly6G, myeloperoxidase (MPO), F4/80, EMCN, iNOS, CD206). An in-vitro assay tested whether recombinant MPO (1 μg/mL) modulates LPS + IFN-γ-induced M1 polarization in RAW264.7 cells.

Results

We c

SUBMITTER: Zhao M 

PROVIDER: S-EPMC12750857 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature