Faculty Collaboration Database

Microglia/macrophages are ultrastructurally altered by their proximity to spinal cord injury in adult female mice. J Neuroinflammation 2023 Nov 21;20(1):273

Date

11/22/2023

Pubmed ID

37990235

Pubmed Central ID

PMC10664529

DOI

10.1186/s12974-023-02953-0

Scopus ID

2-s2.0-85177459005 (requires institutional sign-in at Scopus site)

Abstract

Traumatic spinal cord injury can cause immediate physical damage to the spinal cord and result in severe neurological deficits. The primary, mechanical tissue damage triggers a variety of secondary damage mechanisms at the injury site which significantly contribute to a larger lesion size and increased functional damage. Inflammatory mechanisms which directly involve both microglia (MG) and monocyte-derived macrophages (MDM) play important roles in the post-injury processes, including inflammation and debris clearing. In the current study, we investigated changes in the structure and function of MG/MDM in the injured spinal cord of adult female mice, 7 days after a thoracic contusion SCI. With the use of chip mapping scanning electron microscopy, which allows to image large samples at the nanoscale, we performed an ultrastructural comparison of MG/MDM located near the lesion vs adjacent regions to provide novel insights into the mechanisms at play post-injury. We found that MG/MDM located near the lesion had more mitochondria overall, including mitochondria with and without morphological alterations, and had a higher proportion of altered mitochondria. MG/MDM near the lesion also showed an increased number of phagosomes, including phagosomes containing myelin and partiallydigested materials. MG/MDM near the injury interacted differently with the spinal cord parenchyma, as shown by their reduced number of direct contacts with synaptic elements, axon terminals and dendritic spines. In this study, we characterized the ultrastructural changes of MG/MDM in response to spinal cord tissue damage in mice, uncovering changes in phagocytic activity, mitochondrial ultrastructure, and inter-cellular interactions within the spinal cord parenchyma.

Author List

St-Pierre MK, González Ibáñez F, Kroner A, Tremblay MÈ

Author

Antje Kroner-Milsch MD, PhD Associate Professor in the Neurosurgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Female
Macrophages
Mice
Microglia
Phagocytes
Spinal Cord
Spinal Cord Injuries