Characterization of laryngeal muscle stem cell survival and proliferation.
OBJECTIVE
Laryngeal muscle and skeletal muscle stem cells (MSC) have been shown to differ in physiological basal activity and responsiveness to stimuli. Given these differences, it is the purpose of this investigation to characterize the in vitro proliferation and survival of laryngeal and skeletal MSC to determine whether intrinsic differences exist that may account for differences noted in vivo.


METHODS
Basic science experiment utilizing rat MSC.


METHODS
Cultures of both laryngeal and skeletal MSC were harvested and equal numbers from both groups were expanded under similar conditions, quantifying cellular population to determine proliferation rate for each population. Increased proliferative potential was confirmed using Western blot analysis of extracellular signal-regulated kinase phosphorylation. As per standard survival assay protocol, cultures were placed in serum-deprived medium and cell survival was assessed by terminal uridine deoxynucleotidyl transferase-mediated dUTP nick end labeling assay at 72 hours.


RESULTS
Our results demonstrated increased proliferation of laryngeal MSC relative to the skeletal MSC when cultured under similar conditions. Western blot demonstrated increased activation of the proliferation pathway, extracellular signal-regulated kinase, in the laryngeal group. There was no detectable difference in the MSC survival between the two groups.


CONCLUSIONS
Compared with skeletal MSC, laryngeal MSC demonstrate increased proliferation and regenerative capacity. This may explain some of the differences in physiological role and responses involved in each cell population's tissue of origin.
Walz
Patrick C
PC
Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.
Hiatt
Kelly K
KK
Naidu
Moumita
M
Halum
Stacey L
SL
D000818:Animals; D017209:Apoptosis; D049109:Cell Proliferation; D002478:Cells, Cultured; D004789:Enzyme Activation; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D007821:Laryngeal Muscles / Q000166:cytology* / Q000201:enzymology; D032448:Myoblasts, Skeletal / Q000166:cytology*; D051381:Rats; D017208:Rats, Wistar; D032496:Satellite Cells, Skeletal Muscle / Q000166:cytology* / Q000201:enzymology
D048049:Extracellular Signal-Regulated MAP Kinases