Natural killer cells do not mediate facial motoneuron survival after facial nerve transection.
The goal of the current study was to determine if natural killer (NK) cells mediate facial motoneuron (FMN) survival following injury. Wild-type (WT), perforin/recombinase activating gene-2 knockout (pfp/RAG-2 KO), and common gamma-chain (gammac)/RAG-2 KO mice received a right facial nerve axotomy. In WT mice, FMN survival was 86+/-1.0% relative to the contralateral control side. In contrast, pfp/RAG-2 and gammac/RAG-2 KO mice exhibited significant decreases in FMN survival ( approximately 20% and approximately 30%, respectively), relative to WT. Reconstitution of pfp/RAG-2 and gammac/RAG-2 KO mice with normal NK cells alone, failed to restore FMN survival levels to those of WT, but did restore functional lytic activity against YAC-1 cells. Reconstitution of pfp/RAG-2 and gammac/RAG-2 KO mice with splenocytes, and pfp/RAG-2 KO mice with CD4+ T-lymphocytes alone or in combination with NK cells, restored FMN survival levels to those of WT. Thus, NK cells appear to not be a component of immune cell-mediated rescue of motoneurons from axotomy induced cell death.
Department of Cell Biology, Neurobiology and Anatomy, Loyola University Medical Center, 2160 South First Avenue, Maywood, IL 60153, USA. scoers@lumc.edu
Susanna C
SC
Byram
Craig J
CJ
Serpe
Stephen B
SB
Pruett
Virginia M
VM
Sanders
Kathryn J
KJ
Jones
D000818:Animals; D019771:Axotomy; D001402:B-Lymphocytes / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002470:Cell Survival / Q000276:immunology; D005154:Facial Nerve / Q000166:cytology / Q000276:immunology*; D020220:Facial Nerve Injuries / Q000276:immunology* / Q000473:pathology; D005260:Female; D007111:Immunity, Cellular / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009046:Motor Neurons / Q000166:cytology / Q000276:immunology*; D015213:Neuroimmunomodulation / Q000502:physiology; D013154:Spleen / Q000166:cytology / Q000276:immunology