In vitro study on interaction between human nucleus pulposus cells and mesenchymal stem cells through paracrine stimulation.
METHODS
Coculture of human nucleus pulposus (NP) cells and mesenchymal stem cells (MSCs) using a noncontact system.


OBJECTIVE
To investigate the interaction between NP cells and MSCs through paracrine stimulation.


BACKGROUND
Cell-based therapies have a potential role in the treatment of intervertebral disc degeneration. Upregulating the viability of NP cells and differentiating MSCs into NP-like cells are potential alternatives to achieve viable cells.


METHODS
Culture plates and inserts were used to coculture MSCs and NP cells without direct contact or exchange of cellular components. Cellular proliferation and RNA expression of selected genes were then evaluated after coculture.


RESULTS
Coculturing slightly promoted the proliferation of MSCs, and expression of collagen I and Fas-associated death domain protein significantly decreased. MSCs, which initially expressed no collagen II, started to show collagen II expression after coculturing; the expression level was highest when the cells were cultured with a higher number of NP cells. On the converse, proliferation of NP cells significantly rose even after cocultured with a few MSCs. Increasing the number of cocultured MSCs did not further enhance proliferation of NP cells. Expression of aggrecan in the NP cells significantly increased when the cells were cultured with a higher number of MSCs.


CONCLUSIONS
The results showed a possible mechanism of interaction between MSCs and NP cells mediated by secreted factors. The most significant effect on NP cells was enhancement of cellular proliferation when they were cocultured with even a small number of MSCs. To differentiate MSCs into NP-like cells with heightened collagen II expression, MSCs must be in an environment containing numerous NP cells.
Yang
Shu-Hua
SH
Department of Orthopedic Surgery, National Taiwan University Hospital Yun-Lin Branch, Douliou City, Yunlin County, Taiwan.
Wu
Chang-Chin
CC
Shih
Tiffany Ting-Fang
TT
Sun
Yuan-Hui
YH
Lin
Feng-Huei
FH
D000328:Adult; D002450:Cell Communication / Q000502:physiology; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D018920:Coculture Techniques / Q000379:methods*; D006801:Humans; D007403:Intervertebral Disc / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D019899:Paracrine Communication / Q000187:drug effects / Q000502:physiology; D016212:Transforming Growth Factor beta / Q000494:pharmacology
D016212:Transforming Growth Factor beta