Synthesis, in vitro characterization, and anti-tumor effects of novel polystyrene-poly(amide-ether-ester-imide) co-polymeric micelles for delivery of docetaxel in breast cancer in Balb/C mice.

OBJECTIVE: The goal of the present work was to make novel co-polymeric micellar carriers for the delivery of docetaxel (DTX). SIGNIFICANCE: Co-polymeric micelles can not only solubilize DTX and eliminate the need for toxic surfactants to dissolve it, but also cause passive targeting of the drug to the tumor and reduce its toxic side effects. METHODS: Poly(styrene-maleic acid) (SMA) was conjugated to poly (amide-ether-ester-imide)-poly ethylene glycol (PAEEI-PEG). Copolymer synthesis was proven by Fourier transform infrared (FTIR) and 1H-nuclear magnetic resonance (1H-NMR). The SMA-PAEEI-PEG micelles loaded with DTX were prepared and their critical micelle concentration (CMC), zeta potential, particle size, entrapment efficiency, and their release efficiency were studied. MCF-7 and MDA-MB231 breast cancer cells were used to evaluate the cellular uptake and cytotoxicity of the micelles. The antitumor activity of the DTX-loaded nanomicelles was measured in Balb/c mice. RESULTS: The FTIR and HNMR spectroscopy confirmed successful conjugation of SMA and PAEEI-PEG. The drug loading efficiency was in the range of 34.01-72.75% and drug release lasted for 120 h. The CMC value of the micelles was affected by the SMA/PAEEI-PEG ratio and was in the range of 29.85-14.28 µg/ml. The DTX-loaded micelles showed five times more cytotoxicity than the free drug. The DTX loaded micelles were more effective in tumor growth suppression in vivo and the animals showed an enhanced rate of survival. CONCLUSION: The results show that the SMA-PAEEI-PEG micelles of DTX could potentially provide a suitable parenteral formulation with more stability, higher cytotoxicity, and improved antitumor activity.

The effect of progesterone and 17-ß estradiol on membrane-bound HLA-G in adipose derived stem cells.

Membrane-bound HLA-G (mHLA-G) discovery on adipose derived stem cells (ADSCs) as a tolerogenic and immunosuppressive molecule was very important. Many documents have shown that HLA-G expression can be controlled via some hormones such as progesterone (P4) and estradiol (E2). Therefore, this study was designed to evaluate progesterone and estradiol effects on mHLA-G in ADSCs at restricted and combination concentrations. Three independent cell lines were cultured in complete free phenol red DMEM and subcultured to achieve suffi cient cells. These cells were treated with P4, E2 and P4 plus E2 at physiologic and pregnancy concentrations for 3 days in cell culture conditions. The HLA-G positive ADSCs was measured via monoclonal anti HLA-G-FITC/MEMG-09 by means of flow cytometry in nine groups. Data were analyzed by one way ANOVA and Tukey's post hoc tests. There were no signifi cant values of the mean percentage of HLA-G positive cells in E2-treated and the combination of P4 plus E2-treated ADSCs compared to control cells (p value>0.05) but P4 had a signifi cant increase on mHLA-G in ADSCs (p value<0.05). High P4 concentration increased mHLA-G but E2 and the combination of P4 plus E2 could not change mHLA-G on ADSCs.

Evaluation of neural gene expression in serum treated embryonic stem cells in Alzheimer's patients.

BACKGROUND: Previous studies confirmed that neural gene expression in embryonic stem cells (ESC) could influence by chemical compounds through stimulating apoptotic pathway. We aimed to use ESCs-derived neural cells by embryoid body formation as an in vitro model for determination of neural gene expression changes in groups that treated by sera from Alzheimer's patients and compare with healthy individuals. MATERIALS AND METHODS: ESC line which was derived from the C57BL/6 mouse strain was used throughout this study. ESC-derived neural cells were treated with serum from Alzheimer's patient and healthy individual. Neural gene expression was assessed in both groups by quantitative real-time polymerase chain reaction analysis. The data was analyzed by SPSS Software (version 18). RESULTS: Morphologically, the reducing in neurite out-growth was observed in neural cells in group, which treated by serum from Alzheimer's patient, while neurite growth was natural in appearance in control group. Microtubule-associated protein 2 and glial fibrillary acidic protein expression significantly reduced in the Alzheimer's patient group compared with the control group. Nestin expression did not significantly differ among the groups. CONCLUSION: Neural gene expression could be reduced in serum treated ESC in Alzheimer's patients.

Tissue Distribution and Systemic Toxicity Evaluation of Raloxifene Targeted Polymeric Micelles of Poly (Styrene-Maleic Acid)-Poly (Amide- Ether-Ester-Imide)-Poly (Ethylene Glycol) Loaded With Docetaxel in Breast Cancer Bearing Mice.

BACKGROUND: Due to the low water solubility of Docetaxel (DTX), it is formulated with ethanol and Tween 80 with lots of side effects. For this reason, special attention has been paid to formulate it in new drug nano-carriers. OBJECTIVE: The goal of this study was to evaluate the safety, antitumor activity and tissue distribution of the novel synthesized Raloxifene (RA) targeted polymeric micelles. METHODS: DTX-loaded RA-targeted polymeric micelles composed of poly(styrene-maleic acid)- poly(amide-ether-ester-imide)-poly(ethylene glycol) (SMA-PAEE-PEG) were prepared and their antitumor activity was studied in MC4-L2 tumor-bearing mice compared with non-targeted micelles and free DTX. Safety of the micelles was studied by Hematoxylin and Eosin (H&E) staining of tumors and major organs of the mice. The drug accumulation in the tumor and major organs was measured by HPLC method. RESULTS: The results showed better tumor growth inhibition and increased survival of mice treated with DTX-loaded in targeted micelles compared to the non-targeted micelles and free DTX. Histopathological studies, H&E staining of tumors and immunohistochemical examination showed the potential of DTX-loaded RA-targeted micelles to inhibit tumor cells proliferation. The higher accumulation of the DTX in the tumor tissue after injection of the micelles compared to the free DTX may indicate the higher uptake of the targeted micelles by the G-Protein-Coupled Estrogen Receptors (GPER). CONCLUSION: The results indicate that RA-conjugated polymeric micelles may be a strong and effective drug delivery system for DTX therapy and uptake of the drug into tumor cells, and overcome the disadvantages and side effects of conventional DTX.

Atorvastatin lipid nanocapsules and gold nanoparticles embedded in injectable thermo-gelling hydrogel scaffold containing adipose tissue extracellular matrix for myocardial tissue regeneration.

This study aimed to prepare, optimise, and characterise the novel hybrid hydrogel scaffold containing atorvastatin lipid nanocapsules (LNCs) and gold nanoparticles (NPs) to improve cardiomyoblasts proliferation and regeneration of myocardium. A thermo-responsive aminated guaran (AGG) hydrogel was prepared to encompass extracellular matrix (ECM) fetched from human adipose tissue. Emulsion phase-inversion technique was used to obtain LNCs. Biocompatibility, tensile strength, conductivity, and proliferation of human myocardial cells of the optimised formulation were studied. The LNCs have a spherical shape, and the optimised formulation showed a mean particle size of 18.79 nm, the zeta potential of - 11.4 mV, drug loading of 99.99%, and release efficiency percent over 72 h was 18.73%. The injectable thermo-sensitive hydrogel prepared using 1 w/v% of AGG, 35 w/w% of ECM, ∼0.5 mg/ml of gold NPs and atorvastatin loaded LNCs showed the best physical characteristics. The hybrid scaffold loaded with atorvastatin and gold NPs improved the proliferation of cardiomyoblasts more than sevenfold with enhanced cell attachment to the scaffold. The tensile strength and the conductivity of the scaffold were 300 kPa and 0.14 S/m, respectively. Injectable hybrid adipose tissue prepared by ECM and AGG hydrogel loaded with atorvastatin and gold NPs showed promising physical characteristics for myocardial tissue engineering.

Cytotoxicity assessment of polyhydroxybutyrate/chitosan/nano- bioglass nanofiber scaffolds by stem cells from human exfoliated deciduous teeth stem cells from dental pulp of exfoliated deciduous tooth.

BACKGROUND: The aim of this study was to compare the cytotoxicity and the biocompatibility of three different nanofibers scaffolds after seeding of stem cells harvested from human deciduous dental pulp. Given the importance of scaffold and its features in tissue engineering, this study demonstrated the construction of polyhydroxybutyrate (PHB)/chitosan/nano-bioglass (nBG) nanocomposite scaffold using electrospinning method. MATERIALS AND METHODS: This experimental study was conducted on normal exfoliated deciduous incisors obtained from 6-year-old to 11-year-old healthy children. The dental pulp was extracted from primary incisor teeth which are falling aseptically. After digesting the tissue with 4 mg/ml of type I collagenase, the cells were cultured in medium solution. Identification of stem cells from human exfoliated deciduous teeth was performed by flowcytometry using CD19, CD14, CD146, and CD90 markers. Then, 1 × 104 stem cells were seeded on the scaffold with a diameter of 10 mm × 0.3 mm. Cell viability was evaluated on days 3, 5, and 7 through methyl thiazol tetrazolium techniques (P < 0.05) on different groups that they are groups included (1) PHB scaffold (G1), (2) PHB/chitosan scaffold (G2), (3) the optimal PHB/chitosan/nBG scaffold (G3), (4) mineral trioxide aggregate (MTA), and (5) the G3 + MTA scaffold (G3 + MTA). Data were analyzed with two-way ANOVA at significance level of P < 0.05. RESULTS: The results indicated that the PHB/chitosan/nBG scaffold and PHB/chitosan/nBG scaffold + MTA groups showed significant difference compared with the PHB/chitosan scaffold and PHB scaffold groups on the 7th day (P < 0.05). CONCLUSION: Thus, it can be concluded that the scaffold with nBG nanoparticles is more biocompatible than the other scaffolds and can be considered as a suitable scaffold for growth and proliferation of stem cells.

Exposure to Global System for Mobile Communication 900 MHz Cellular Phone Radiofrequency Alters Growth, Proliferation and Morphology of Michigan Cancer Foundation-7 Cells and Mesenchymal Stem Cells.

BACKGROUND: Today, using cellular phone and its harmful effects in human life is growing. The aim of this study is to investigate the effect of the global system for mobile communication (GSM) 900 MHz cellular phone radiofrequency waves on growth, morphology, and proliferation rate of mesenchymal stem cells and Michigan Cancer Foundation (MCF-7) cells within the specific distance and intensity. METHODS: MCF-7 and human adipose-derived stem cells (HADSCs) were exposed to GSM cellular phones 900 MHz frequency with intensity of 354.6 µW/cm2 during different exposure times 6, 21, 51, and 101 min/day with an interval of 10 min for each subsequent radiation exposure for 3 and 5 days at 10 and 20 cm distances from antenna. 3-(4,5-dimethythiazol- 2-yl)-2,5-diphenyl tetrazolium bromide assay and trypan blue test were used to determine the growth of cells and cell viability, respectively. Statistical analyses were carried out using three-way ANOVA. Differences were significant when P < 0.05. RESULTS: The proliferation rates of both MCF-7 and HADSCs cells in all exposure groups were significantly lower than controls (P < 0.05). There was a significant effect on the percentage of cell survival with increase the period of time from 3 to 5 days for MCF-7 (P < 0.01) and HADSCs (P = 0.02), respectively. Variations in distance had no significant effect on the percentage of cell survival (P = 0.35) on MCF-7 (P = 0.02) and HADSCs (P = 0.09) cells, respectively. CONCLUSIONS: The results showed that radiation of GSM 900 MHz cellular phone may be reduced cell viability and proliferation rates of both cells. It is recommended to reduce exposure time, increase distance from antenna, and reserve the use of cell phones for shorter conversations to prevent its biological and harmful effects. Further studies with other intensities and frequencies on different cells are recommended.

Preparation and in vitro evaluation of novel cross-linked chondroitin sulphate nanoparticles by aluminium ions for encapsulation of green tea flavonoids.

Chondroitin sulphate is a sulphated glycosaminoglycan biopolymer composed over 100 individual sugars. Chondroitin sulphate nanoparticles (NPs) loaded with catechin were prepared by an ionic gelation method using AlCl3 and optimised for polymer and cross-linking agent concentration, curing time and stirring speed. Zeta potential, particle size, loading efficiency, and release efficiency over 24 h (RE24%) were evaluated. The surface morphology of NPs was investigated by scanning electron microscopy and their thermal behaviour by differential scanning calorimetric. Antioxidant effect of NPs was determined by chelating activity of iron ions. The cell viability of mesenchymal stem cells was determined by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide assay and the calcification of osteoblasts was studied by Alizarin red staining. The optimised NPs showed particle size of 176 nm, zeta potential of -20.8 mV, loading efficiency of 93.3% and RE24% of 80.6%. The chatechin loaded chondroitin sulphate NPs showed 70-fold more antioxidant activity, 3-fold proliferation effect and higher calcium precipitation in osteoblasts than free catechin.

Synthesis and In vitro/In vivo Characterization of Raloxifene Grafted Poly(Styrene Maleic Acid)-Poly(Amide-Ether-Ester-Imide) Micelles for Targeted Delivery of Docetaxel in G Protein-Coupled Estrogen Receptor Breast Cancer.

BACKGROUND: To reduce the nonspecifically distribution of chemotherapeutic agents throughout the whole body, which causes severe toxicity in normal tissues, targeting them towards a receptor overexpressed on tumor tissue, is a promising method for cancer therapy. OBJECTIVE: The aim of the present study was development of novel copolymeric micelles of raloxifene targeted Styrene Maleic Acid-Poly Amide Ether Ester Imide-Poly Ethylene Glycol (SMA-PAEEI-PEG-RA) and loading them with Docetaxel (DTX). METHODS: Successful synthesis of the targeted copolymer was confirmed by FTIR and C-NMR spectroscopy. The micelles physicochemical properties like morphology, particle size, poly dispersity index, zeta potential, drug loading, release, stability, in vitro cytotoxicity and cellular uptake were analyzed. The in vivo antitumor activity of DTX-loaded micelles were assessed and compared with free DTX and non-targeted micelles in breast cancer bearing Balb-c mice. RESULTS: Particle sizes, zeta potentials and the encapsulation efficiency of the drug in targeted micelles were 115.9- 142.8 nm, -4.9 to -12.9 mV, and 54.1-67.8%, respectively. Cell toxicity tests showed that IC50 of DTX-loaded SMAPAEEI- PEG-RA micelles increased five-fold as compared with free DTX. Survival rate of the mice improved more effectively than free DTX so that, the percentage of increase in lifespan (ILS%) and the tumor inhibition ratio (TIR) changed from 41.66% and 51.19% in free drug to 83.33% and 78.57% in the targeted micelles, respectively. CONCLUSION: Therefore, the raloxifene conjugated PEG-derived micelles may provide a novel and effective delivery system for DTX in breast cancer.

Tissue engineering: Dentin - pulp complex regeneration approaches (A review).

Dental pulp is a highly specialized tissue that preserves teeth. It is important to maintain the capabilities of dental pulp before a pulpectomy by creating a local restoration of the dentin-pulp complex from residual dental pulp. The articles identified were selected by two reviewers based on entry and exit criteria. All relevant articles indexed in PubMed, Springer, Science Direct, and Scopus with no limitations from 1961 to 2016 were searched. Factors investigated in the selected articles included the following key words: Dentin-Pulp Complex, Regeneration, Tissue Engineering, Scaffold, Stem Cell, and Growth Factors. Of the 233 abstracts retrieved, the papers which were selected had evaluated the clinical aspects of the application of dentin-pulp regeneration. Generally, this study has introduced a new approach to provoke the regeneration of the dentin-pulp complex after a pulpectomy, so that exogenous growth factors and the scaffold are able to induce cells and blood vessels from the residual dental pulp in the tooth root canal. This study further presents a new strategy for local regeneration therapy of the dentin-pulp complex. This review summarizes the current knowledge of the potential beneficial effects derived from the interaction of dental materials with the dentin-pulp complex as well as potential future developments in this exciting field.

Indoleamine 2,3-Dioxygenase Is Dispensable for The Immunomodulatory Function of Stem Cells from Human Exfoliated Deciduous Teeth.

OBJECTIVE: In this study, we sought to better understand the immunoregulatory function of stem cells derived from human exfoliated deciduous teeth (SHED). We studied the role of the interferon gamma (IFN-γ)-indoleamine 2,3-dioxygenase (IDO)-axis in immunoregulation of SHED compared to bone marrow derived mesenchymal stem cells (BMMSCs) under the same conditions. MATERIALS AND METHODS: In this cross-sectional study, recently isolated human T cells were stimulated either by mitogen or inactivated allogeneic peripheral blood mononuclear cells (PBMCs). These T cells were subsequently co-cultured with, either SHED or BMMSCs in the presence or absence of 1-methyl-tryptophan (1-MT) or neutralizing anti- human-IFN-γ antibodies. In all co-cultures we evaluated lymphocyte activation as well as IDO activity. RESULTS: SHED, similar to conventional BMMSCs, had anti-proliferative effects on stimulated T cells and reduced their cytokine production. This property of SHED and BMMSCs was changed by IFN-γ neutralization. We detected IDO in the immunosuppressive supernatant of all co-cultures. Removal of IDO decreased the immunosuppression of BMMSCs. CONCLUSION: SHED, like BMMSCs, produced the IDO enzyme. Although IFN-γ is one of inducer of IDO production in SHED, these cells were not affected by IFN-γ in the same manner as BMMSCs. Unlike BMMSCs, the IDO enzyme did not contribute to their immunosuppression and might have other cell-type specific roles.

Injectable natural polymer compound for tissue engineering of intervertebral disc: In vitro study.

Intervertebral disc degeneration is recognized to be the leading cause for chronic low-back pain. Injectable hydrogel is one of the great interests for tissue engineering and cell encapsulation specially for intervertebral (IVD) affecting rate of regeneration success, in this study we assessed viscoelastic properties of a Chitosan-ß glycerophosphate-hyaluronic acid, Chondroitin-6-sulfate, type 2 of Collagen, gelatin, fibroin silk (Ch-ß-GP-HA-CS-Col-Ge-FS) hydrogel which was named as NP hydrogel that is natural extracellular matrix of IVD. Chitosan-based hydrogel was made in the ratio of 1.5%: 7%: 1%:1%:1%-1.5%-1% (Ch: ß-GP: HA-CS-Col-Ge-FS). Gelation time and other rheological properties were studied using amplitude sweep and frequency sweep tests. Also, the cytotoxicity of the hydrogel invitro assessed by MTT and trypan blue tests. Morphology of the hydrogel and attachment of NP cells were evaluated by SEM. Our result showed that NP hydrogel in 4°C is an injectable transparent solution. It started gelation in 37°C after about 30min. Gelation temperature of NP hydrogel was 37°C. Storage modulus (G') of this hydrogel at 37°C was almost constant over a wide range of strain. MTT and trypan blue tests showed hydrogel was cytocompatible. The obtained results suggest that this hydrogel would be a natural and cytocompatible choice as an injectable scaffold for using in vivo study of IVD regeneration.

Biodegradable nanocomposite coatings accelerate bone healing: In vivo evaluation.

BACKGROUND: The aim of this study was to evaluate the interaction of bioactive and biodegradable poly (lactide-co-glycolide)/bioactive glass/hydroxyapatite (PBGHA) and poly (lactide-co-glycolide)/bioactive glass (PBG) nanocomposite coatings with bone. MATERIALS AND METHODS: Sol-gel derived 58S bioactive glass nanoparticles, 50/50 wt% poly (lactic acid)/poly (glycolic acid) and hydroxyapatite nanoparticles were used to prepare the coatings. The nanocomposite coatings were characterized by scanning electron microscopy, X-ray diffraction and atomic force microscopy. Mechanical stability of the prepared nanocomposite coatings was studied during intramedullary implantation of coated Kirschner wires (K-wires) into rabbit tibia. Titanium mini-screws coated with nanocomposite coatings and without coating were implanted intramedullary in rabbit tibia. Bone tissue interaction with the prepared nanocomposite coatings was evaluated 30 and 60 days after surgery. The non-parametric paired Friedman and Kruskal-Wallis tests were used to compare the samples. For all tests, the level of significance was P < 0.05. RESULTS: The results showed that nanocomposite coatings remained stable on the K-wires with a minimum of 96% of the original coating mass. Tissue around the coated implants showed no adverse reactions to the coatings. Woven and trabecular bone formation were observed around the coated samples with a minimum inflammatory reaction. PBG nanocomposite coating induced more rapid bone healing than PBGHA nanocomposite coating and titanium without coating (P < 0.05). CONCLUSION: It was concluded that PBG nanocomposite coating provides an ideal surface for bone formation and it could be used as a candidate for coating dental and orthopedic implants.

The effect of stem cell from human exfoliated deciduous teeth on T lymphocyte proliferation.

BACKGROUND: Mesenchymal stem cells (MSC), a specific type of adult tissue stem cell; have the immunosuppressive effects that make them valuable targets for regenerative medicine and treatment of many human illnesses. Hence, MSC have been the subject of numerous studies. The classical source of MSC is adult bone marrow (BM). Due to many shortcomings of harvesting MSC from BM, finding the alternative sources for MSC is an urgent. Stem cells from human exfoliated deciduous teeth (SHED) are relative new MSC populations that fulfill these criteria but their potential immunosuppressive effect has not been studied enough yet. Thus, in this work the effect of SHED on the proliferation of in vitro activated T lymphocytes were explored. MATERIALS AND METHODS: In this study, both mitogen and alloantigen activated T cells were cultured in the presence of different numbers of SHED. In some co-cultures, activated T cells were in direct contact to MSCs and in other co-cultures; they were separated from SHED by a permeable membrane. In all co-cultures, the proliferation of T cells was measured by ELISA Bromodeoxyuridine proliferation assay. RESULTS: In general, our results showed that SHED significantly suppress the proliferation of activated T cells in a dose-dependent manner. Moreover, the suppression was slightly stronger when MSCs were in physical contact to activated T cells. CONCLUSION: This study showed that SHED likewise other MSC populations can suppress the activation of T lymphocytes, which can be used instead of BM derived MSCs in many investigational and clinical applications.

Comparing the immunoregulatory effects of stem cells from human exfoliated deciduous teeth and bone marrow-derived mesenchymal stem cells.

Stem cells from human exfoliated deciduous teeth (SHED) have been introduced recently and possess characteristics similar to mesenchymal stem cells (MSCs). Because of their convenient accessibility and safety of harvest, SHED can be a preferable source for the ever-increasing MSCs' applications  While they are new, their immunoproperties have not been adequately studied. In this study, we aimed to explore the effect of SHED on T lymphocytes and compare it to conventional MSCs (BMMSCs).At first the isolated T lymphocytes were activated specifically/nonspecifically in vitro and cocultured with SHED or BMMSCs under the same conditions, subsequently their proliferation and cytokine secretion (IL-2 and IFN-γ) were measured.In our experiment, BMMSCs and SHED inhibit the proliferation and cytokine production of both PHA and alloantigen stimulated T lymphocytes in a dose-dependent manner. In direct and indirect contact to T lymphocytes, the inhibition of BMMSCs (but not of SHED) was significantly different The cytokine production from activated T cells was affected differently by two types of MSCs. The inhibition decreased by the separation of lymphocytes and MSCs by a semipermeable membrane, but it was not abolished.This study showed that SHED suppress the activation of human T lymphocytes in vitro like other MSCs. Compared to BMMSCs, this suppression was alleviated. In the equal conditions, the pattern of immune-modulation of BMMSCs and SHED was different, suggesting that SHED do not exert the exact mechanisms of BMMSCs' immunosuppression., This finding should be verified by further studies focused on the detailed mechanisms  of the immunomodulation of SHED and also BMMSCs.

Adipose derived stem cells for treatment of mandibular bone defects: An autologous study in dogs.

BACKGROUND: The aim of this research was to evaluate the effect of adipose derived stem cells on bone repair in through and through mandibular bone defects of canine. MATERIALS AND METHODS: In this prospective comparative study, adipose-derived stem cells were isolated from subcutaneous fat of lateral thoracic area of 4 dogs. The isolated cells were cultured and expanded through 3 passages. The undifferentiated stem cells were seeded in Collatamp and transferred into mandibular bone through-and-through defects. Similar defects on control group were filled with cell-free Collatamp. After 6 weeks, biopsies were taken and histomorphometric analysis was performed. The percentage of new bone formation was measured in each case. The data were subject to statistical analysis using the Wilcoxon test. Differences at P≤0.05 were considered significant. RESULTS: H and E staining of decalcified samples revealed more bone formation in the group, which stem cells were seeded. Cell-free collatamp group revealed an average bone regeneration of %41±13.21, while adipose derived stem cell-seeded collatamp group showed %49±8.24. CONCLUSION: The use of stem cell seeded collatamp scaffold in mandibular defects caused more bone regeneration.

Phenotypic characterizations and comparison of adult dental stem cells with adipose-derived stem cells.

OBJECTIVES: Mesenchymal stem cells or "multipotent stromal cells" are heterogeneous cell population with self-renewal and multilinage differentiation. The aim of this study was to examine and compare the expression of important stem cell surface markers on two populations of mesenchymal stem cells, one derived from human exfoliated deciduous teeth and the other derived from human adipose tissue. These new stem cells will offer a promising avenue for prevention and reversal of many human diseases such as type 1 diabetes and prevention of liver fibrotic process. METHODS: Mesenchymal stem cells were isolated and cultured from human adipose tissue and dental pulp of human exfoliated deciduous teeth. The cultured cells then were harvested and stained by different fluorescent labeled monoclonal antibodies against surface markers and were analyzed using flow cytometry. RESULTS: Both different cell populations expressed CD44, CD90 and CD13 (stem cell markers) with similar intensity. They did not express hematopoietic markers (CD11b, CD19 and CD34), and lymphocyte or leukocyte antigens CD3, CD7, CD20, CD14, CD45, CCR5 (CD195), CD11b and CD10 on their surfaces. Two different cell types demonstrated different levels of expression in CD56 and CD146. Mesenchymal stem cells from human exfoliated deciduous teeth were positive for CD105 and were negative for CCR3 and CCR4 expression. CONCLUSIONS: Both cell populations derived from adipose tissue and dental pulp showed common phenotypic markers of mesenchymal stem cells. In conclusion, mesenchymal stem cells could be isolated and cultured successfully from dental pulp of human exfoliated deciduous teeth, they are very good candidates for treatment and prevention of human diseases.