[The involvement of ERK pathway in the cellular phenotype conversion in human mesenchymal stem cells cocultured with human sweat gland cells].
OBJECTIVE
To study the cellular phenotype conversion of human mesenchymal stem cells (MSCs) cocultured with human sweat gland cells (SGCs) and the contribution of extracellular signal-regulated kinase (ERK) pathway in the process.


METHODS
MSC and SGC were isolated, amplified , and identified with two-step immunohistochemistry method. The primary SGCs were heat-shocked at 47 degrees C. Then the supernatants were collected immediately and 24hr later. The 3rd passage of MSCs were divided into control, SGC supernatant (cells were cultured in DMEM/F12 medium containing 30% SGC supernatant), SGC supernatant + EGF (cells were cultured in DMEM/F12 medium containing 30% SGC supernatant and 50 microg/L EGF), and SGC supernatant + PD98059 (cells were cultured in DMEM/F12 medium containing 30% SGC supernatant and 10 micromol/L PD98059) groups. The positive expression of CK7and CEA in MSCs were detected on the 7th post-stimulation day (PSD) by flow cytometry. The expression of ERK and phosphorylated ERK were determined with Western blotting.


RESULTS
The positive expression rate of CK7 and CEA was (5.76 +/-0.10)%, (2.01 +/- 0.09)% in SGC supernatant group; (7.31 +/- 0.21)% and (7.27 +/- 0.12)% in SGC supernatant + EGF group; and (1.63 +/- 0.11)%, (1.54 +/- 0.07)% in SGC supernatant + PD98059 group; they were all obviously higher than that in control group (P < 0.01). Moreover, ERK expression was observed in all groups. The expression of pERK in SGC supernatant + EGF group was higher than that in SGC supernatant group, but almost no expression of pERK was found in the SGC supernatant + PD98059 and control groups.


CONCLUSIONS
Indirect coculture of MSCs with SGCs can induce the phenotype conversion of MSCs through ERK pathway.
Ouyang
Yun-shu
YS
Aesthetic and Plastic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100005 , P. R. China. oy81@163.com
Jia
Chi-yu
CY
Qi
Ke-ming
KM
Fu
Xiao-bing
XB
D000293:Adolescent; D001854:Bone Marrow Cells / Q000166:cytology; D002478:Cells, Cultured; D018920:Coculture Techniques; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D020935:MAP Kinase Signaling System; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D013545:Sweat Glands / Q000166:cytology / Q000378:metabolism*
D048049:Extracellular Signal-Regulated MAP Kinases