Open AccessLymphocytes Are Not Required for Neurogenic Heterotopic Ossification Development after Spinal Cord Injury
Author(s) -
Kylie A. Alexander,
HsuWen Tseng,
Irina Kulina,
Whitney Fleming,
Cédryck Vaquette,
F. Genêt,
Marc J. Ruitenberg,
JeanPierre Lévesque
Publication year - 2022
Publication title -
neurotrauma reports
Language(s) - English
Resource type - Journals
ISSN - 2689-288X
DOI - 10.1089/neur.2021.0072
Subject(s) - pathogenesis , heterotopic ossification , ossification , medicine , spinal cord , immune system , spinal cord injury , spleen , pathology , immunology , anatomy , psychiatry
Neurogenic heterotopic ossifications (NHOs) are incapacitating complications of traumatic brain and spinal cord injuries (SCI) that manifest as abnormal bone formation in periarticular muscles. Using a unique model of NHO after SCI in genetically unmodified mice, we have previously established that the innate immune system plays a key driving role in NHO pathogenesis. The role of adaptive immune cells in NHO pathogenesis, however, remains unexplored in this model. Here we established that B lymphocytes were reduced in the spleen and blood after SCI and increased in muscles of mice in which NHO develops, whereas minimal changes in T cell frequencies were noted. Interestingly, Rag1 -/- mice lacking mature T and B lymphocytes, developed NHO, similar to wild-type mice. Finally, mice that underwent splenectomy before SCI and muscle damage also developed NHO to the same extent as non-splenectomized SCI controls. Overall, our findings show that functional T and B lymphocytes have minimal influence or dispensable contributions to NHO development after experimental SCI in mice.