IADR Abstract Archives
Salivary Gland ECM Induces Differentiation of BM-MSCs to Epithelial-like Cells
Objectives: Salivary gland (SG) hypofunction is often associated with xerostomic drugs, radiation for head and neck cancer, or autoimmune diseases (e.g. Sjögren’s syndrome) and severely affects oral and systemic health and quality of life. At present, therapy is primarily symptomatic, consisting of saliva substitutes or stimulants, with no definitive cure. Recently, stem cell-based therapies have been proposed for regenerating damaged SG tissues, but little is known about the effect of SG extracellular matrix (ECM) (i.e. the SG cell microenvironment or niche) on multipotent stem cell function. The present study investigates whether SG-ECM can induce transdifferentiation of bone marrow-derived mesenchymal stem cells (BM-MSCs).
Methods: Passage 1 Lewis rat BM-MSCs were incubated (1hr at 37°C) with decellularized rat submandibular ECM (rSM-ECM) and washed with PBS. ECM-treated and untreated cells were then cultured for 7 or 14 days in α-MEM containing 20% FBS at 37°C and 5%CO2/95% air on tissue culture plastic (TCP). At the end of culture, immunohistochemistry and gene expression (RT-PCR) analyses for amylase and tight junction proteins (tjp-1, claudin-1 and -3, occludin), respectively, were performed. Cell aggregates were carefully released from rSM-ECM-treated cultures, and then subcultured on Matrigel-coated plates for an additional 21 days.
Results: After 7 days in culture, cells pretreated with rSM-ECM were a mixture of cell aggregates and a flat monolayer of cells, while the untreated BM-MSCs were predominantly a flat monolayer. After 14 days, Gene expression of the rSM-ECM-treated cells showed an increase in claudin-3 and occludin as compared to the untreated cells. Moreover, immunofluorescence staining for amylase was more intense in the rSM-ECM-treated group vs. the untreated controls. Cell aggregates from the rSM-ECM-treated cultures displayed duct-like structures after 3 weeks of culture on Matrigel.
Conclusions: Our findings suggest that SG-ECM proteins direct BM-MSC differentiation to the epithelial cell lineage.
Methods: Passage 1 Lewis rat BM-MSCs were incubated (1hr at 37°C) with decellularized rat submandibular ECM (rSM-ECM) and washed with PBS. ECM-treated and untreated cells were then cultured for 7 or 14 days in α-MEM containing 20% FBS at 37°C and 5%CO2/95% air on tissue culture plastic (TCP). At the end of culture, immunohistochemistry and gene expression (RT-PCR) analyses for amylase and tight junction proteins (tjp-1, claudin-1 and -3, occludin), respectively, were performed. Cell aggregates were carefully released from rSM-ECM-treated cultures, and then subcultured on Matrigel-coated plates for an additional 21 days.
Results: After 7 days in culture, cells pretreated with rSM-ECM were a mixture of cell aggregates and a flat monolayer of cells, while the untreated BM-MSCs were predominantly a flat monolayer. After 14 days, Gene expression of the rSM-ECM-treated cells showed an increase in claudin-3 and occludin as compared to the untreated cells. Moreover, immunofluorescence staining for amylase was more intense in the rSM-ECM-treated group vs. the untreated controls. Cell aggregates from the rSM-ECM-treated cultures displayed duct-like structures after 3 weeks of culture on Matrigel.
Conclusions: Our findings suggest that SG-ECM proteins direct BM-MSC differentiation to the epithelial cell lineage.