In VitroCharacterization of Multipotent Mesenchymal Stromal Cells Isolated from Palatal Subepithelial Tissue Grafts

Abstract

The aim of this study was to analyze whether the mesenchymal stromal cells (MSCs) isolated from palatal tissue grafts harvested in order to cover gingival recessions have the basic characteristics of stem cells. The palatal tissue cells were processed using a special culture medium that stimulated the development of only undifferentiated cellular lines. Cells at passage 4 were evaluated by flow cytometry to examine the expression of specific surface markers and were tested for multilineage differentiation capacity. These cells collected at passage 4 were also investigated for the capacity to cluster into embryoid body aggregates. Palatal MSCs displayed positive staining for the mesenchymal markers CD29, CD73, CD105, CD 49e, and CD44, but did not express hematopoietic markers CD34/45. The palatal MSCs successfully differentiated into osteogenic, adipogenic, and chondrogenic lineages. When seeded in special conditions, palatal MSCs propagated into unattached spheres resembling embryoid body aggregates consisting both of differentiated and undifferentiated cells as revealed at the ultrastructural evaluation. It is concluded that the isolated palatal MSCs fulfilled the basic criteria defining the stem cells. This new source of stem cells characterized here for the first time opens new perspectives on possible applications in basic research and in regenerative medicine.

Comparison of Different Sources of Mesenchymal Stem Cells: Palatal versus Lipoaspirated Adipose Tissue

“…Stem cells have also been isolated from new, more accessible sources, including gingiva [Yang et al, 2013], oral mucosa, palatal connective tissue [Roman et al, 2013], and palatal periosteum [Caballero et al, 2010]. The main goal of the present study was to characterize and compare a novel stem cell population obtained from PAT-and LAT-derived stem cells.…”

“…Its capability for rapid regeneration may be explained by the potential presence of at least one stem cell type within the tissue or by the existence of growth factors, such as basic fibroblast growth factor, in saliva [Grimm et al, 2014]. Previous research suggested that PAT provided an accessible source of MSCs, which could be used for tissue engineering and tissue regeneration of extraoral tissues in periodontal disease [Roman et al, 2013]. Research also showed that stem cells derived from palatal tissue could be of enormous benefit in regenerative processes.…”

“…In a previous study, MSCs, including adipose tissuederived MSCs, were isolated from a split-thickness connective tissue graft and harvested from the palatal premolar region [Roman et al, 2013]. In the present study, MSCs were isolated from adipose tissue using a different method, and adipose-derived stem cells were obtained from PAT and lipoaspirated adipose tissue (LAT).…”

“…To date, stem cells have been isolated from a variety of oral tissues, including gingiva [Zhang et al, 2009], periodontal ligament (PDL) [Seo et al, 2004;Hakki et al, 2014], and palatal connective tissue [Roman et al, 2013;Grimm et al, 2014]. They have also been isolated from dental tissues, such as dental papilla [Ikeda et al, 2006], dental follicles [Morsczeck et al, 2005], dental pulp from natal teeth [Karaöz et al, 2010], deciduous teeth [Gronthos et al, 2000;Miura et al, 2003], and adult teeth [Hakki et al, 2015].…”

“…The characteristics of palatal tissue-derived cells, which are also called progenitor-like cells, were first described by Roman et al [2012]. In later work, they demonstrated that these cells possessed basic characteristics of mesenchymal stem cells (MSCs) [Roman et al, 2013].…”