Regenerative Potential of Human Schneiderian Membrane: Progenitor Cells and Epithelial‐Mesenchymal Transition

Abstract

An innate osteogenic potential of the Schneiderian membrane (SM) is progressively assessed in studies ranging from non-human species to human subjects. It has relevance for endosteal placement and osseointegration. Nestin-expressing osteogenic progenitor cells are allegedly involved in bone formation and remodelling. Nestin phenotype was not assessed previously in human SM. We therefore aimed to fill that particular gap in the literature. Bioptic samples of human adult SM were obtained during surgery from eight adult patients, operated for nonmalignant pathologies. Immunohistochemistry on paraffin-embedded tissue samples used primary antibodies against nestin, CD45, CD146, cytokeratin 7 (CK7), and alpha-smooth muscle actin (a-SMA). Nestin expression was consistently found in endothelial cells, and was scarcely encountered in pericytes, putative stromal stem/progenitor cells, as well as in glandular epithelial cells. Moreover, woven bone formation in the periosteal layer of the SM can also be regarded as evidence of the osteogenic potential of this membrane. Nestin and CD45 expression in cells of the primary bone supports the osteogenic potential of SM nestinexpressing cells and a possible involvement of hematopoietic stem cells in maxillary sinus floor remodeling. CD146, a known inducer of epithelial-mesenchymal transition (EMT), was expressed in epithelia, as was CK7. Isolated stromal cells were found expressing CD146, CK7 and a-SMA, suggesting that regenerative processes happening in the SM may also involve processes of EMT which generate stem/progenitor cells.

Radiographic and Histomorphometric Evaluation of Biomaterials Used for Lateral Sinus Augmentation: A Systematic Review on the Effect of Residual Bone Height and Vertical Graft Size on New Bone Formation and Graft Shrinkage

“…It has long been shown that NBF occurs in the maxillary sinus via sinus mucosa lifting without using any graft type [ 76 , 77 , 78 ], supporting the thesis of the osteogenic capability of the Schneiderian membrane. Although the debate is ongoing, this hypothesis has been confirmed by in vivo and in vitro studies [ 79 , 80 ] that also demonstrated the presence of mesenchymal progenitor cells and cells committed to the osteogenic lineage in the membrane itself [ 81 , 82 ]. The obtained results suggested that a lower Schneiderian membrane elevation may be sufficient to trigger its osteogenic potential efficiently, as compared to grafting a greater amount of biomaterial, which would be counterproductive.…”

A Synopsis of Signaling Crosstalk of Pericytes and Endothelial Cells in Salivary Gland

“…Moreover, HNC-EXOs can bolster the malignant behavior of tumor cells by the distribution of SHH, initiating the non-canonical RHO/ROCK signaling cascade, enhancing the expression of MMP9, and being positively affiliated with MVD [ 243 ]. Isolated CD146 + CK7 + alpha-SMA stromal cells in the Schneiderian membrane may be involved in EMT-related regenerative processes [ 244 ]. Considering their role as potential disease biomarkers, SGT-EXOs present dissimilarities compared with healthy individuals [ 245 ].…”

Nestin Expression Is Associated with Relapses in Head and Neck Lesions

“…Also, nestin staining may even indicate that human oral mucosa can be an effective source for hard tissue regeneration [ 7 ] and tooth tissue engineering applications [ 8 ]. In relation to the maxillary sinus, the regenerative potential of the Scheneiderian membrane has been postulated, associated with the presence of progenitor cells that express nestin [ 6 , 26 ], but the authors have not found any studies that analyse expression in lesions located in the nasosinus region. Luo et al [ 19 ], studied the expression of embryonic stem cell markers (SOX2, OCT4 and NANOg) in nasopharyngeal lesions, with the aim of analysing EMT.…”