Mesenchymal stem cells (MSC) hold great potential for regenerative medicine because of their ability for self-renewal and differentiation into tissue-specific cells such as osteoblasts, chondrocytes, and adipocytes. MSCs orchestrate tissue development, maintenance and repair, and are useful for musculoskeletal regenerative therapies to treat age-related orthopedic degenerative diseases and other clinical conditions. Importantly, MSCs produce secretory factors that play critical roles in tissue repair that support both engraftment and trophic functions (autocrine and paracrine). The development of uniform protocols for both preparation and characterization of MSCs, including standardized functional assays for evaluation of their biological potential, are critical factors contributing to their clinical utility. Quality control and release criteria for MSCs should include cell surface markers, differentiation potential, and other essential cell parameters. For example, cell surface marker profiles (surfactome), bone-forming capacities in ectopic and orthotopic models, as well as cell size and granularity, telomere length, senescence status, trophic factor secretion (secretome), and immunomodulation, should be thoroughly assessed to predict MSC utility for regenerative medicine. We propose that these and other functionalities of MSCs should be characterized prior to use in clinical applications as part of comprehensive and uniform guidelines and release criteria for their clinical-grade production to achieve predictably favorable treatment outcomes for stem cell therapy. Stem Cells Translational Medicine 2017;6:2173-2185.

/pdf/concise-review-multifaceted-characterization-of-human-2rcqfk9c60.pdf

Concise Review: Multifaceted Characterization of Human Mesenchymal Stem Cells for Use in Regenerative Medicine.

Osteochondral tissue engineering: Current strategies and challenges

https://www.jstage.jst.go.jp/article/jpr/56/3/56_S1883-1958-12-00060-6/_pdf

Stem cells in dentistry – Part I: Stem cell sources

Bone regeneration mediated by biomimetic mineralization of a nanofiber matrix.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/jor.21230

Bridging the gap: Bone marrow aspiration concentrate reduces autologous bone grafting in osseous defects

Purpose:To evaluate the influence of bone marrow aspirate added to xenograft or alloplast graft matrix scaffold to produce bone.Materials:A maximum of 4 cc bone marrow was aspirated from the anterior iliac crest of 5 patients to saturate the matrix scaffold prior to bone graft. Seven graft sites eva

A histomorphogenic analysis of bone grafts augmented with adult stem cells.

Many edentulous posterior maxilla are found to be encumbered by alveolar resorption and increased pneumatization of the sinus. These factors limit the quantity and quality of bone necessary for successful implant placement in these areas. One solution is to use shorter implants, but this often results in an unfavorable crown-root ratio. To create an improved environment in such regions, the classic sinus floor elevation with bone augmentation is a well-accepted technique. However, when the edentulous area is limited to a zone between 1 and 2 teeth, lifting the membrane becomes difficult and may subject it to iatrogenic injury. The antral membrane balloon elevation technique, which is introduced in this preliminary report, is a modification of the currently used sinus lift. It elevates the membrane easily and makes the antral floor accessible for augmentation with grafting materials.

Antral Membrane Balloon Elevation

Bone regeneration requires an orchestrated interaction between various cells and other biological components. The synthesis of bone matrix with the release of cellular cytokines and growth factors facilitates and regulates cell growth. This leads to the maturation of bone that can support functional implants. Bone-marrow aspirate is a rich source of cells, cytokines, and growth factors needed for bone formation. Harvesting the marrow from the anterior iliac crest is a simple, safe, and cost-effective procedure. Mixing it with a resorbable scaffold and transplanting it to a site can predictably enhance bone regeneration. This article explores the anatomy of the bone marrow and describes the necessary elements for successful bone grafts, such as cells, bone matrix, and cellular regulators (both soluble and insoluble).

Bone marrow: orchestrated cells, cytokines, and growth factors for bone regeneration.

Background:The advent of monoclonal antibody stem cell marker technology has made it possible to identify a variety of human stem cells and their progeny. Specific markers exist for cells related to bone healing and bone regeneration. These include but are not limited to hematopoietic, mesenchymal,

Toward the identification of mesenchymal stem cells in bone marrow and peripheral blood for bone regeneration.

Purpose To evaluate the influence of bone marrow aspirate when added to bone block allograft to repair osseous defects. Background Bone-marrow aspirate has been combined with xenograft and allograft particulate material and has produced a significant quantity of new bone growth. However, the use of allograft bone blocks has advantages in some clinical situations. This article discusses cell-based therapies by means of in vivo transplantation of stem cells derived from bone-marrow aspirate and incorporated into allograft corticocancellous bone block for bone regeneration. Materials A technique for combining bone-marrow aspirate with block allografts was developed. To evaluate its influence in repairing osseous defects, a maximum of 3 to 4 mL of bone marrow was aspirated from the anterior iliac crest of 5 patients who had severely atrophic maxillary and mandibular ridges. Five sites were grafted with allograft bone blocks saturated with bone-marrow aspirate and secured with bone screws (ACE Surgical Supply Company, Inc. Brockton, MA). At one of the sites a core specimen was taken 4 months after implant placement and submitted for standard histologic and histomorphometric analysis. Results After 4 to 8 months of healing, all the grafts had integrated into the recipient bone. Implants were placed at all 5 sites and osseointegrated successfully. Examination of the bone core showed the graft to be well-integrated, with 54% of the core consisting of bone and 46% of marrow. Eighty-nine percent of the bone was vital. Conclusion Impregnation of bone-marrow aspirate into allograft bone block activates the body's ability to form new bone. The bone-marrow aspiration technique is less invasive than harvesting autogenous bone from a second surgical site, offers predictable results, and is cost effective.

Dennis Smiler

Papers

A histomorphogenic analysis of bone grafts augmented with adult stem cells.

Antral Membrane Balloon Elevation

Bone marrow: orchestrated cells, cytokines, and growth factors for bone regeneration.

Toward the identification of mesenchymal stem cells in bone marrow and peripheral blood for bone regeneration.

Bone block allograft impregnated with bone marrow aspirate.