Samer Srouji

Technion - Israel Institute of Technology, H̱efa, Haifa District, Israel

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Publications (38)101.99 Total impact

  • S. Srouji · R. Gasper · M. Gustavo
    International Journal of Oral and Maxillofacial Surgery 10/2013; 42(10):1268. DOI:10.1016/j.ijom.2013.07.329 · 1.36 Impact Factor
  • S. SROUJI
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    ABSTRACT: Objectives: Maxillary sinus membrane lifting is a common procedure aimed at increasing the volume of the maxillary sinus osseous floor prior to inserting dental implants. Recently we proved in vitro and in vivo assay the osteogenic potential of Schneiderian membrane. The purpose of this study was to evaluate the amount of bone formation under a sinus Schneiderian membrane tented with implants without bone graft material. Methods: fifteen patients (20 sinus augmentations, 42 dental implants of MIS Ltd. system) were consecutively treated with sinus floor elevation via the lateral window approach with minimum 4 mm subantral bone. Osteotomy made with round Drill 5 mm radius in the anterior wall of the sinus, and the sinus membrane was elevated to make a new compartment. To achieve implant stability in of remaining levels of vertical subantral bone, the protocol of installing the MIS system dental implant was modified in its last preparation step. The compartment around the implants under the sinus mucosal lining in the sinus floor filled with blood from surrounding bleeding. And dental membrane (MIS Ltd.) placed on the open window. All patients recalled for Clinical and X-ray fellow up till the time of the dental implant uncovering. In all cases, samples were taken for biopsy at the time of second stage surgery. Results: An average of 6.9 months after the sinus augmentation, new bone consolidation in the maxillary sinus was observed by radiographic and histologic evaluation. Vital bone formation was 71.4% according to the histomorphometric data. Of the 42 implants placed, 3 failed. The overall implant survival rate was 92.9%. Conclusions: This clincal study supports our previous in vivo and in vitro studies and suggests that simultaneous placement of dental implants and blood clot as graft material appears to be safe and predictable alternative procedure for maxillary sinus augmentation.
    IADR Israeli Division Meeting 2013; 06/2013
  • J. HAJ · H. KARMAN · S. SROUJI
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    ABSTRACT: Objectives: As bone is the second most frequently transplanted tissue in humans, extensive research efforts are being focused on developing an ideal structure of bone generated of cell-based scaffold in vitro. The objective of the present study was to create a novel biocompatible hybrid scaffold composed of electrospun polymeric nanofibers that is combined with osteoconductive ceramic. The unique composition and architecture of such scaffold has the ability to support osteogenic differentiation of human MSCs leading to bone production. Material and Methods: To produce the hybrid scaffold made of both nanofibers and ceramic particles (Preosteon), an apparatus was built consisting of a particles' disperser which scattered the ceramic particles on the nanofibers while they were being produced by the electrospinning technique. The scaffold was characterized by defining the morphology, porosity and mechanical properties. Bone marrow derived human MSCs were isolated and expanded in alphaMEM medium containing osteogenic reagents or factors. MSCs were thereafter seeded onto the hybrid scaffold. Adhesion and proliferation of seeded cells was assessed by the standard protocol of Alamar Blue assay. Also, scanning electron microscopy (SEM) and histological examination were employed to test integration of cells within the scaffold. Results: The images of SEM have revealed a 3D meshed structure of the hybrid scaffolds containing nano-scale fibers and micro-scale of ceramic particles. The scaffold exhibited high porosity and thereby cells could easily migrate and adhere onto the nanofibers and ceramic particles, as well as grow and proliferate as determined by techniques of SEM and histological H&E staining. Conclusion: The fabricated hybrid scaffold has exhibited a 3D meshed structure comprised of nano- and micro-scale fibers imitating the extracellular matrix of bone tissue. The scaffold supports proliferation of MSCs as well as their differentiation to osteoprogenitors. The hybrid scaffold can be utilized for cell-based therapy of bone tissue engineering.
    IADR Israeli Division Meeting 2013; 06/2013
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    ABSTRACT: Bone repair strategies utilizing resorbable biomaterial implants aim to stimulate endogenous cells in order to gradually replace the implant with functional repair tissue. These biomaterials should therefore be biodegradable, osteoconductive, osteoinductive, and maintain their integrity until the newly formed host tissue can contribute proper function. In recent years there has been impressive clinical outcomes for this strategy when using osteoconductive hydrogel biomaterials in combination with osteoinductive growth factors such as human recombinant bone morphogenic protein (hrBMP-2). However, the success of hrBMP-2 treatments is not without risks if the factor is delivered too rapidly and at very high doses because of a suboptimal biomaterial. Therefore, the aim of this study was to evaluate the use of a PEGylated fibrinogen (PF) provisional matrix as a delivery system for low-dose hrBMP-2 treatment in a critical size maxillofacial bone defect model. PF is a semi-synthetic hydrogel material that can regulate the release of physiological doses of hrBMP-2 based on its controllable physical properties and biodegradation. hrBMP-2 release from the PF material and hrBMP-2 bioactivity were validated using in vitro assays and a subcutaneous implantation model in rats. Critical size calvarial defects in mice were treated orthotopically with PF containing 8 μg/ml hrBMP-2 to demonstrate the capacity of these bioactive implants to induce enhanced bone formation in as little as 6 weeks. Control defects treated with PF alone or left empty resulted in far less bone formation when compared to the PF/hrBMP-2 treated defects. These results demonstrate the feasibility of using a semi-synthetic biomaterial containing small doses of osteoinductive hrBMP-2 as an effective treatment for maxillofacial bone defects.
    Biomaterials 01/2013; 34(12). DOI:10.1016/j.biomaterials.2013.01.035 · 8.31 Impact Factor
  • W. HAJ · S. SROUJI
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    ABSTRACT: Objectives: Burning mouth syndrome(BMS) is a chronic disorder that is characterized by continuous burning sensation located in the apparent­ly normal oral mucosa. The different treatments used to date without clearly successful results. The aim of this study was to evaluate the clinical charac­teristics of the syndrome, and the improvement obtained as a result of different treatment modalities. Methods: A retrospective study was conducted by reviewing the medical records of 72 patients with BMS who presented at the Carmel Medical Center’s Department of Oral and Maxillofacial Surgery from April 2009 to February 2012. The clinical variables examined included age, gender, duration, onset, location of the burning sensation, daily variations, relationship with meals, accompanying oral manifestations, and other chronic pain. Pain intensity was measured using a visual analog scale (VAS) applied at baseline and after four weeks of treatment. Results: Mean patient age was 71.75±18.52 years, women to men ratio was 11:1, mean duration of the syndrome was 4.65±2.52 years. 40.28% had onset after dental treatment. The tongue was the most frequently affected location(94.44%). 61.11% had minimal burning intensity at morning and exacerbation during the day, 48.61% reported improvement during meals, 36.11% had concomitant complaint of taste alteration and 29.16% xerostomia, 68.05% had another chronic pain. Conversation with the patients and explanation about the syndrome gave the best results. Anxiolytic drugs and Alpha lipoic acid also showed significant differences in recorded VAS score. Conclusions: patients with BMS usually referred from one health care professional to another without effective management, a thing that has a significant emotional impact on them, so the first line of treatment should be patient reassurance by understanding their problem, giving them a full explanation about it, and make them realize that it's real, and not of their imagination. Clonazepam and Alpha lipoic acid seems to be partially effective.
    PER/IADR Congress 2012; 09/2012
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    ABSTRACT: AimSinus augmentation procedures commonly employ osteoconductive scaffolding materials to stimulate and support bone formation. The aim of this study was to develop a simple screening methodology for the evaluation of the osteoconductive potential of various bone graft materials prior to clinical use. Materials and methodsMaterials tested were Bio-Oss, Bi-Ostetic, OraGraft, and ProOsteon. These Simple and composite bone substitutes were embedded with osteoprogenitor cells derived from either the human maxillary sinus schneiderian membrane (hMSSM) or from maxillary tuberosity bone marrow and then monitored both in vitro and in vivo. ResultsCell adherence and proliferation was most pronounced in OraGraft, followed by ProOsteon. In vivo bone formation, within the bone graft, was also observed, with most marked results in OraGraft and ProOsteon grafts. Conclusions The proposed osteoconductivity testing method proved simple, informative, and reliable for the purpose of screening candidate biomaterials for sinus lifting or sinus augmentation.
    Clinical Oral Implants Research 08/2012; 24(12). DOI:10.1111/j.1600-0501.2012.02571.x · 3.12 Impact Factor
  • Adi Rachmiel · Samer Srouji · Omri Emodi · Dror Aizenbud
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    ABSTRACT: Obstructive sleep apnea (OSA) in pediatric populations is often associated with congenital craniofacial malformations resulting in decreased pharyngeal airway, which in severe cases leads to tracheostomy dependence. The purpose of this study was to use distraction osteogenesis to improve the airway and decannulate the tracheostomy. This study involved 11 OSA tracheostomy-dependent patients (age range, 4 months to 6 years) who underwent bilateral distraction in the mandibular body using extraoral distraction devices. Following a latency period of 4 days, gradual distraction at a rate of 1 mm/d was performed followed by a consolidation period of 10 weeks. Three-dimensional computed tomography reconstruction of the face and neck before and after the mandibular lengthening aided in quantitative volumetric evaluation of mandibular volume and airway volume. The results demonstrated mandibular elongation of a mean of 30 mm on each side, an increase in mandibular volume by an average of 29.19%, and increase in pharyngeal airway by an average of 70.53%. Two to 3 months following the last lengthening, all 11 patients were decannulated with improvement of signs and symptoms of OSA and elimination of oxygen requirement. Mean follow-up was 2.0 years. The oxygen saturation level rose to more than 95%, and the apnea index respiratory disturbance index was less than 2 episodes per hour for all patients. Bilateral mandibular distraction is a useful method in younger children to decannulate permanent tracheostomy expanding the hypoplastic mandible and concomitantly advance the base of tongue and hyoid bone increasing the pharyngeal airway.
    The Journal of craniofacial surgery 03/2012; 23(2):459-63. DOI:10.1097/SCS.0b013e3182413db8 · 0.68 Impact Factor
  • Erella Livne · Samer Srouji
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    ABSTRACT: The need for tissue repair is one of the major concerns of reconstructive surgery and in aging and disease. Fracture healing is regulated by osteogenic cells and growth factors. The ability to enhance healing of bone defects and fractures can contribute to prevent the complications of long-term immobilization that are especially fatal in old age. Three-dimensional scaffold provides the necessary support for cells to proliferate and maintain their differentiated function and its architecture defines the shape of the newly formed bone. At the same time the scaffold is biodegraded providing space for the newly formed tissue. Skeletal tissue such as bone is organized into three-dimensional structure (3D) in the body. The 3D scaffold can be used as a temporary device containing the osteogenic cells. This could provide the initial conditions for bone repair. Biodegradable scaffold contains committed osteogenic stem cells and growth factors which serve as a graft substitute for bone and cartilage repair. Bone marrow stem cells (MSCs) are selected as the osteogenic subpopulations cultured in medium supplemented with osteogenic supplements. The selected osteogenic subpopulation is identified using osteogenic markers (Alizarin red, von Kossa staining, osteocalcin, osteonectin, osteopontin, immunolocalization, and mineral-hydroxyapatite (HA) deposition).
    Principles of Bone Regeneration, 01/2012: pages 97-117; , ISBN: 978-1-4614-2058-3
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    ABSTRACT: Tissue engineering sustains the need of a three-dimensional (3D) scaffold to promote the regeneration of tissues in volume. Usually, scaffolds are seeded with an adequate cell population, allowing their growth and maturation upon implantation in vivo. Previous studies obtained by our group evidenced significant growth patterns and osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) when seeded and cultured on melt-based porous chitosan fibre mesh scaffolds (cell constructs). Therefore, it is crucial to test the in vivo performance of these in vitro 3D cell constructs. In this study, chitosan-based scaffolds were seeded and cultured in vitro with hBMSCs for 3 weeks under osteogenic stimulation conditions and analysed for cell adhesion, proliferation and differentiation. Implantation of 2 weeks precultured cell constructs in osteogenic culture conditions was performed into critical cranial size defects in nude mice. The objective of this study was to verify the scaffold integration and new bone formation. At 8 weeks of implantation, scaffolds were harvested and prepared for micro-computed tomography (µCT) analysis. Retrieved implants showed good integration with the surrounding tissue and significant bone formation, more evident for the scaffolds cultured and implanted with human cells. The results of this work demonstrated that chitosan-based scaffolds, besides supporting in vitro proliferation and osteogenic differentiation of hBMSCs, induced bone formation in vivo. Thus, their osteogenic potential in orthotopic location in immunodeficient mice was validated, evidencing good prospects for their use in bone tissue-engineering therapies.
    Journal of Tissue Engineering and Regenerative Medicine 01/2012; 6(1):21-8. DOI:10.1002/term.391 · 4.43 Impact Factor
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    ABSTRACT: Abstract Adult human mesenchymal stromal cells (hMSCs) are an important source for tissue repair in regenerative medicine. Notably, targeted gene therapy in hMSCs to promote osteogenic differentiation may help in the development of novel therapeutic approaches for bone repair. We recently showed that α5 integrin (ITGA5) promotes osteoblast differentiation in bone marrow-derived hMSCs. Here, we determined whether lentiviral (LV)-mediated expression of ITGA5 in hMSCs derived from the bone-marrow stroma of healthy individuals may promote bone repair in vivo in two relevant critical-size bone defects in the mouse. In a first series of experiments, control or LV-ITGA5-transduced hMSCs were seeded on collagen-based gelatin sponge and transplanted in a cranial critical-size defect (5 mm) in Nude-Foxn1nu mice. Microcomputed tomography and quantitative histological analyses after 8 weeks showed no or little de novo bone formation in defects implanted with collagen sponge alone or with hMSCs, respectively. In contrast, implantation of collagen sponge with LV-ITGA5-transduced hMSCs showed greater bone formation compared with control hMSCs. We also tested the bone-repair potential of LV-mediated ITGA5 expression in hMSCs in a critical-size long-bone defect (2 mm) in femur in Nude-Foxn1nu mice. Bone remnants were stabilized with external fixation, and control or LV-ITGA5-transduced hMSCs mixed with coral/hydroxyapatite particles were transplanted into the critical-size long-bone defect. Histological analysis after 8 weeks showed that LV-ITGA5-transduced hMSCs implanted with particles induced 85% bone regeneration and repair. These results demonstrate that repair of critical-size mouse cranial and long-bone defects can be induced using LV-mediated ITGA5 gene expression in hMSCs, which provides a novel gene therapy for bone regeneration.
    Human gene therapy 09/2011; 23(2):167-72. DOI:10.1089/hum.2011.059 · 3.62 Impact Factor
  • S. Srouji · J. McCain
    Journal of Oral and Maxillofacial Surgery 09/2011; 69(9). DOI:10.1016/j.joms.2011.06.086 · 1.28 Impact Factor
  • Bone 05/2011; 48. DOI:10.1016/j.bone.2011.03.387 · 4.46 Impact Factor
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    ABSTRACT: Animal models for preclinical functionality assays lie midway between in vitro systems such as cell culture and actual clinical trials. We have developed a novel external fixation device for femoral critical size defect (CSD) in the femurs of immunodeficient mice as an experimental model for studying bone regeneration and bone tissue engineering. The external fixation device comprises four pointed rods and dental acrylic paste. A segmental bone defect (2 mm) was created in the midshaft of the mouse femur. The CSD in the femur of the mice were either left untreated or treated with a bone allograft, a cell-scaffold construct, or a scaffold-only construct. The repair and healing processes of the CSD were monitored by digital x-ray radiography, microcomputed tomography, and histology. Repair of the femoral CSD was achieved with the bone allografts, and partial repair of the femoral CSD was achieved with the cell scaffold and the scaffold-only constructs. No repair of the nongrafted femoral CSD was observed. Our results establish the feasibility of this new mouse femoral model for CSD repair of segmental bone using a simple stabilized external fixation device. The model should prove especially useful for in vivo preclinical proof-of-concept studies that involve cell therapy-based technologies for bone tissue engineering applications in humans.
    Tissue Engineering Part C Methods 05/2011; 17(5):597-606. DOI:10.1089/ten.TEC.2010.0501 · 4.64 Impact Factor
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    ABSTRACT: The design of mat-like scaffolds slow-releasing bone morphogenetic protein-2 (BMP-2) retaining bone regeneration functions has been a major challenge in tissue engineering. This study aimed to develop core-shell fiber scaffolds releasing BMP-2 to support bone regeneration. BMP-2 was incorporated in an aqueous core solution of poly(ethylene oxide), whereas the shell solution was made of polycaprolactone blended with poly(ethylene glycol). This blending induced pores in the shell, which pronouncedly affected the movement of proteins out of the fibers. BMP-2 release profiles were monitored. In vitro bioactivity of BMP-2 released from the scaffolds was assessed using human mesenchymal stem cells by measuring alkaline phosphatase activity. Bone regeneration capabilities were demonstrated by implanting the BMP-2-embedded scaffolds in rat cranial defect model followed by micro-computed tomography analysis. The degree of fiber's shell porosity, highly correlative with the slow- and fast-release patterns of BMP-2, were found to be dependent on the relative amount of poly(ethylene glycol) within the shell. In vitro assays of scaffolds manifesting the slow-release pattern have revealed significant (∼9-fold) increase in alkaline phosphatase activity, compared to fast BMP-2 releasing scaffolds. Likewise, in vivo studies have revealed significant bone regeneration in cranial defects of scaffold implants with recombinant human BMP-2 with slow-release pattern.
    Tissue Engineering Part A 02/2011; 17(3-4):269-77. DOI:10.1089/ten.TEA.2010.0250 · 4.64 Impact Factor
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    ABSTRACT: Bone is the second most frequently transplanted tissue in humans and efforts are focused on developing cell-scaffold constructs which can be employed for autologous implantation in place of allogenic transplants. The objective of the present study was to examine the efficacy of a gelatin-based hydrogel scaffold to support osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (MSCs) and its application in a cranial defect model. MSCs which were cultured on hydrogel under osteogenic conditions demonstrated typical osteogenic differentiation which included cluster formation with positive Alizarin Red S staining, sedimentation of calcium phosphate as defined by SEM and EDS spectroscopy and expression of mRNA osteogenic markers. Empty scaffolds or those containing either differentiated cells or naïve cells were implanted into cranial defects of athymic nude mice and the healing process was followed by μCT. Substantial bone formation (65%) was observed with osteogenic cell-scaffold constructs when compared to the naïve cell construct (25%) and the cell free scaffold (10%). Results demonstrated the potential of hydrogel scaffolds to serve as a supportive carrier for bone marrow-derived MSCs.
    Journal of cranio-maxillo-facial surgery: official publication of the European Association for Cranio-Maxillo-Facial Surgery 10/2010; 39(5):364-71. DOI:10.1016/j.jcms.2010.09.001 · 2.60 Impact Factor
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    ABSTRACT: The use of stem cells for tissue engineering (TE) encourages scientists to design new platforms in the field of regenerative and reconstructive medicine. Human embryonic stem cells (hESC) have been proposed to be an important cell source for cell-based TE applications as well as an exciting tool for investigating the fundamentals of human development. Here, we describe the efficient derivation of connective tissue progenitors (CTPs) from hESC lines and fetal tissues. The CTPs were significantly expanded and induced to generate tendon tissues in vitro, with ultrastructural characteristics and biomechanical properties typical of mature tendons. We describe a simple method for engineering tendon grafts that can successfully repair injured Achilles tendons and restore the ankle joint extension movement in mice. We also show the CTP's ability to differentiate into bone, cartilage, and fat both in vitro and in vivo. This study offers evidence for the possibility of using stem cell-derived engineered grafts to replace missing tissues, and sets a basic platform for future cell-based TE applications in the fields of orthopedics and reconstructive surgery.
    Tissue Engineering Part A 10/2010; 16(10):3119-37. DOI:10.1089/ten.TEA.2009.0716 · 4.64 Impact Factor
  • S. SROUJI · D. BEN DAVID · M. RIMINNUCI · P. BIANCO
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    ABSTRACT: Objectives: Maxillary sinus membrane lifting is a common procedure aimed at increasing the volume of the maxillary sinus osseous floor prior to inserting dental implants. However, the biological nature of bone regeneration and the role of Schneiderian membrane in sinus lifting procedures are unclear. The aim of this work was to test the osteogenic potential of human maxillary sinus Schneiderian membrane (hMSSM) using both in vitro and in vivo assays. Methods: Samples of hMSSM were used for deriving cells cultured for histological studies. Analyses of flow cytometry were performed on various passages of cell cultures (P0, P1, and P2) using known markers of mesenchymal progenitor cells e.g. CD 105, CD 146, CD 71, CD 73, and CD 166. The ability of hMSSM-derived cells to undergo osteogenic differentiation in culture was analyzed using relevant assays in vitro. The inherent osteogenic potential of hMSSM was also strengthened by experiments in vivo: 1. Sinus membrane-derived cells were implanted subcutaneously in an immunodeficient mouse. 2. A pocket-like structure of folded membrane was transplanted subcutaneously in immunodeficient mice for 8 weeks, aiming to mimic natural clinical conditions. Results: Results have shown that hMSSM cells could be induced to express alkaline phosphatase, bone morphogenic protein-2, osteopontin, osteonectin, and osteocalcin as well as to mineralize their extracellular matrix. Inherent osteogenic potential of hMSSM-derived cells was further proven by in vivo experiments. Bone formation was demonstrated hisologically at ectopic sites following transplantation of hMSSM-derived cells in conjunction with an osteoconductive ceramic as well as within the pocket-like structure of folded hMSSM. Conclusions: This study provides further biological insights for understanding the clinical phenomenon of maxillary sinus membrane lifting. Our results show a genuine osteogenic potential of hMSSM which can contribute to successful sinus augmentation techniques.
    IADR General Session 2010; 07/2010
  • S Srouji · D Ben-David · R Lotan · M Riminucci · E Livne · P Bianco
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    ABSTRACT: Maxillary sinus membrane lifting is a common procedure aimed at increasing the volume of the maxillary sinus osseous floor prior to inserting dental implants. Clinical observations of bone formation in sinus lifting procedures without grafting bone substitutes were observed, but the biological nature of bone regeneration in sinus lifting procedures is unclear. This study tested whether this osteogenic activity relies on inherent osteogenic capacity residing in the sinus membrane by simulating the in vivo clinical condition of sinus lifting in an animal model. Maxillary sinus membrane cells were cultured in alpha-MEM medium containing osteogenic supplements (ascorbic acid, dexamethasone). Cultured cells revealed alkaline phosphatase activity and mRNA expression of osteogenic markers (alkaline phosphatase, bone sialoprotein, osteocalcin and osteonectin) verifying the osteogenic potential of the cells. Fresh tissue samples demonstrated positive alkaline phosphatase enzyme activity situated along the membrane-bone interface periosteum-like layer. To simulate the in vivo clinical conditions, the membranes were folded to form a pocket-like structure and were transplanted subcutaneously in immunodeficient mice for 8 weeks. New bone formation was observed in the transplants indicating the innate osteogenic potential within the maxillary Schneiderian sinus membrane and its possible contribution to bone regeneration in sinus lifting procedures.
    International Journal of Oral and Maxillofacial Surgery 04/2010; 39(8):793-801. DOI:10.1016/j.ijom.2010.03.009 · 1.36 Impact Factor
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    ABSTRACT: Adult human mesenchymal stromal cells (hMSCs) have the potential to differentiate into chondrogenic, adipogenic, or osteogenic lineages, providing a potential source for tissue regeneration. An important issue for efficient bone regeneration is to identify factors that can be targeted to promote the osteogenic potential of hMSCs. Using transcriptome analysis, we found that integrin alpha5 (ITGA5) expression is up-regulated during dexamethasone-induced osteoblast differentiation of hMSCs. Gain-of-function studies showed that ITGA5 promotes the expression of osteoblast phenotypic markers and in vitro osteogenesis of hMSCs. Down-regulation of endogenous ITGA5 using specific shRNAs blunted osteoblast marker gene expression and osteogenic differentiation. Molecular analyses showed that the enhanced osteoblast differentiation induced by ITGA5 was mediated by activation of focal adhesion kinase/ERK1/2-MAPKs and PI3K signaling pathways. Remarkably, activation of endogenous ITGA5 using agonists such as a specific antibody that primes the integrin or a peptide that specifically activates ITGA5 was sufficient to enhance ERK1/2-MAPKs and PI3K signaling and to promote osteoblast differentiation and osteogenic capacity of hMSCs. Importantly, we demonstrated that hMSCs engineered to overexpress ITGA5 exhibited a marked increase in their osteogenic potential in vivo. Taken together, these findings not only reveal that ITGA5 is required for osteoblast differentiation of adult hMSCs but also provide a targeted strategy using ITGA5 agonists to promote the osteogenic capacity of hMSCs. This may be used for tissue regeneration in bone disorders where the recruitment or capacity of hMSCs is compromised.
    Proceedings of the National Academy of Sciences 11/2009; 106(44):18587-91. DOI:10.1073/pnas.0812334106 · 9.81 Impact Factor
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    ABSTRACT: Recent studies successfully demonstrated induction of new bone formation in the maxillary sinus by mucosal membrane lifting without the use of any graft material. The aim of this work was to test the osteogenic potential of human maxillary sinus Schneiderian membrane (hMSSM) using both in vitro and in vivo assays. Samples of hMSSM were used for establishment of cell cultures and for histological studies. Flow cytometry analysis was performed on P(0), P(1), and P(2) cultures using established mesenchymal progenitor cell markers (CD 105, CD 146, CD 71, CD 73, CD 166), and the ability of hMSSM cells to undergo osteogenic differentiation in culture was analyzed using relevant in vitro assays. Results showed that hMSSM cells could be induced to express alkaline phosphatase, bone morphogenic protein-2, osteopontin, osteonectin, and osteocalcin and to mineralize their extracellular matrix. Inherent osteogenic potential of hMSSM-derived cells was further proven by in vivo experiments, which demonstrated the formation of histology-proven bone at ectopic sites following transplantation of hMSSM-derived cells in conjunction with an osteoconductive scaffold. This study provides the biological background for understanding the observed clinical phenomena in sinus lifting. Our results show that a genuine osteogenic potential is associated with the hMSSM and can contribute to development of successful sinus augmentation techniques.
    Calcified Tissue International 02/2009; 84(2):138-45. DOI:10.1007/s00223-008-9202-x · 2.75 Impact Factor

Publication Stats

778 Citations
101.99 Total Impact Points

Institutions

  • 2009–2013
    • Technion - Israel Institute of Technology
      • Faculty of Mechanical Engineering
      H̱efa, Haifa District, Israel
    • Sapienza University of Rome
      • Laboratory of Experimental Medicine and Pathology Environmental
      Roma, Latium, Italy
  • 2004–2013
    • Carmel Medical Center
      H̱efa, Haifa, Israel
  • 2002–2005
    • Rambam Medical Center
      • Department of Oral and Maxillofacial Surgery
      H̱efa, Haifa District, Israel