Distribution of bone marrow-derived cells in the vestibular end organs and the endolymphatic sac.
CONCLUSIONS
Bone marrow-derived cells (BMDCs) are constitutively present in the vestibular end organs and in the endolymphatic sac, and may play a role in the maintenance of inner ear homeostasis.


OBJECTIVE
The aim was to examine the distribution and characteristics of BMDCs in the vestibular end organs and in the endolymphatic sac.


METHODS
Bone marrow-chimeric mice were generated by bone marrow transplantation from mice genetically labeled with enhanced green fluorescent protein to C57 Bl/6 mice to visualize BMDCs. Three months after bone marrow transplantation, inner ear specimens were processed for histochemical analyses.


RESULTS
BMDCs were widely distributed in the vestibular end organs and the endolymphatic sac, whereas there were differences in the phenotype and the distribution between the vestibular end organs and the endolymphatic sac. A subpopulation of BMDCs in the vestibular end organs expressed antigen-presenting protein MHC class II. Moreover, the density of BMDCs in the vestibular end organs increased in response to local mechanical stress.
Okano
Takayuki
T
Department of Otolaryngology, Head and Neck Surgery, Kyoto University, Kyoto, Japan.
Nakagawa
Takayuki
T
Ito
Juichi
J
D000818:Animals; D001854:Bone Marrow Cells / Q000502:physiology*; D016026:Bone Marrow Transplantation; D002135:Calcium-Binding Proteins / Q000378:metabolism; D004712:Endolymphatic Sac / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D049452:Green Fluorescent Proteins; D017493:Leukocyte Common Antigens / Q000378:metabolism; D049408:Luminescent Agents; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008840:Microfilament Proteins
C491049:Aif1 protein, mouse; D002135:Calcium-Binding Proteins; D049408:Luminescent Agents; D008840:Microfilament Proteins; D049452:Green Fluorescent Proteins; D017493:Leukocyte Common Antigens