Collagen–PCL Sheath–Core Bicomponent Electrospun Scaffolds Increase Osteogenic Differentiation and Calcium Accretion of Human Adipose-Derived Stem Cells

Human adipose-derived stem cells (hASCs) are an abundant cell source capable of osteogenic differentiation, and have been investigated as an autologous stem cell source for bone tissue engineering applications. The objective of this study was to determine if the addition of a type-I collagen sheath to the surface of poly(ε-caprolactone) (PCL) nanofibers would enhance viability, proliferation and osteogenesis of hASCs. This is the first study to examine the differentiation behavior of hASCs on collagen–PCL sheath–core bicomponent nanofiber scaffolds developed using a co-axial electrospinning technique. The use of a sheath–core configuration ensured a uniform coating of collagen on the PCL nanofibers. PCL nanofiber scaffolds prepared using a conventional electrospinning technique served as controls. hASCs were seeded at a density of 20 000 cells/cm² on 1 cm² electrospun nanofiber (pure PCL or collagen–PCL sheath–core) sheets. Confocal microscopy and hASC proliferation data confirmed the presence of viable cells after 2 weeks in culture on all scaffolds. Greater cell spreading occurred on bicomponent collagen–PCL scaffolds at earlier time points. hASCs were osteogenically differentiated by addition of soluble osteogenic inductive factors. Calcium quantification indicated cell-mediated calcium accretion was approx. 5-times higher on bicomponent collagen–PCL sheath–core scaffolds compared to PCL controls, indicating collagen–PCL bicomponent scaffolds promoted greater hASC osteogenesis after two weeks of culture in osteogenic medium. This is the first study to examine the effects of collagen–PCL sheath–core composite nanofibers on hASC viability, proliferation and osteogenesis. The sheath–core composite fibers significantly increased calcium accretion of hASCs, indicating that collagen–PCL sheath–core bicomponent structures have potential for bone tissue engineering applications using hASCs.     

A comparative study of proliferation and osteogenic differentiation of adipose-derived stem cells on akermanite and beta-TCP ceramics

This study investigated the in vitro effects of akermanite, a new kind of Ca-, Mg-, Si-containing bioceramic, on the attachment, proliferation and osteogenic differentiation of human adipose-derived stem cells (hASCs). Parallel comparison of the cellular behaviors of hASCs on the akermanite was made with those on beta-tricalcium phosphate (beta-TCP). Scanning electron microscope (SEM) observation and fluorescent DiO labeling were carried out to reveal the attachment and growth of hASCs on the two ceramic surfaces, while the quantitative assay of cell proliferation with time was detected by DNA assay. Osteogenic differentiation of hASCs cultured on the akermanite and beta-TCP was assayed by ALP expression and osteocalcin (OCN) deposition, which was further confirmed by Real-time PCR analysis for markers of osteogenic differentiation. It was shown that hASCs attached and spread well on the akermanite as those on beta-TCP, and similar proliferation behaviors of hASCs were observed on the two ceramics. Both of them exhibited good compatibility to hASCs with only minor cytotoxicity as compared with the tissue culture plates. Interestingly, the osteogenic differentiation of hASCs could be enhanced on the akermanite compared with that on the beta-TCP when the culture time was extended to approximately 10 days. Thus, it can be ascertained that akermanite ceramics may serve as a potential scaffold for bone tissue engineering.     

New Adipose Tissue Formation by Human Adipose-Derived Stem Cells with Hyaluronic Acid Gel in Immunodeficient Mice

Background: Currently available injectable fillers have demonstrated limited durability. This report proposes the in vitro culture of human adipose-derived stem cells (hASCs) on hyaluronic acid (HA) gel for in vivo growth of de novo adipose tissue.Methods: For in vitro studies, hASCs were isolated from human adipose tissue and were confirmed by multi-lineage differentiation and flow cytometry. hASCs were cultured on HA gel. The effectiveness of cell attachment and proliferation on HA gel was surveyed by inverted light microscopy. For in vivo studies, HA gel containing hASCs, hASCs without HA gel, HA gel alone were allocated and subcutaneously injected into the subcutaneous pocket in the back of nude mice (n=6) in each group. At eight weeks post-injection, the implants were harvested for histological examination by hematoxylin and eosin (H&E) stain, Oil-Red O stain and immunohistochemical staining. The human-specific Alu gene was examined.Results: hASCs were well attachment and proliferation on the HA gel. In vivo grafts showed well-organized new adipose tissue on the HA gel by histologic examination and Oil-Red O stain. Analysis of neo-adipose tissues by PCR revealed the presence of the Alu gene. This study demonstrated not only the successful culture of hASCs on HA gel, but also their full proliferation and differentiation into adipose tissue.Conclusions: The efficacy of injected filler could be permanent since the reduction of the volume of the HA gel after bioabsorption could be replaced by new adipose tissue generated by hASCs. This is a promising approach for developing long lasting soft tissue filler.     

Fabrication and characterization of chitosan/OGP coated porous poly(ε-caprolactone) scaffold for bone tissue engineering

As one of the stimulators on bone formation, osteogenic growth peptide (OGP) improves both proliferation and differentiation of the bone cells in vitro and in vivo. The aim of this work was the preparation of three dimensional porous poly(ε-caprolactone) (PCL) scaffold with high porosity, well interpore connectivity, and then its surface was modified by using chitosan (CS)/OGP coating for application in bone regeneration. In present study, the properties of porous PCL and CS/OGP coated PCL scaffold, including the microstructure, water absorption, porosity, hydrophilicity, mechanical properties, and biocompatibility in vitro were investigated. Results showed that the PCL and CS/OGP-PCL scaffold with an interconnected network structure have a porosity of more than 91.5, 80.8%, respectively. The CS/OGP-PCL scaffold exhibited better hydrophilicity and mechanical properties than that of uncoated PCL scaffold. Moreover, the results of cell culture test showed that CS/OGP coating could stimulate the proliferation and growth of osteoblast cells on CS/OGP-PCL scaffold. These finding suggested that the surface modification could be a effective method on enhancing cell adhesion to synthetic polymer-based scaffolds in tissue engineering application and the developed porous CS/OGP-PCL scaffold should be considered as alternative biomaterials for bone regeneration.     

Exogenously added BMP-6, BMP-7 and VEGF may not enhance the osteogenic differentiation of human adipose stem cells

Abstract

In the present study bone morphogenetic protein (BMP)-6 alone or in synergy with BMP-7 and vascular endothelial growth factor (VEGF) were tested with human adipose stem cells (hASCs) seeded on cell culture plastic or 3D bioactive glass. Osteogenic medium (OM) was used as a positive control for osteogenic differentiation. The same growth factor groups were also tested combined with OM. None of the growth factor treatments could enhance the osteogenic differentiation of hASCs in 3D- or 2D-culture compared to control or OM. In 3D-culture OM promoted significantly total collagen production, whereas in 2D-culture OM induced high total ALP activity and mineralization compared to control and growth factors groups, but also high cell proliferation. In this study, hASCs did not respond to exogenously added growth although various parameters of the study set-up may have affected these findings contradictory to the previous literature.     

Enhancement of tenogenic differentiation of human adipose stem cells by tendon-derived extracellular matrix

Mesenchymal stem cells (MSCs) have gained increasing research interest for their potential in improving healing and regeneration of injured tendon tissues. Developing functional three-dimensional (3D) scaffolds to promote MSC proliferation and differentiation is a critical requirement in tendon tissue engineering. Tendon extracellular matrix has been shown to maintain the tenogenic potential of tendon stem cells and stimulate tenogenesis of human adipose stem cells (hASCs) in 2D culture. This study aims at characterizing the biological composition of urea-extracted fraction of tendon ECM (tECM) and its tenogenic effect on hASCs cultured in a 3D collagen scaffold under uniaxial tension. The tECM obtained was cell-free and rich in ECM proteins. hASCs seeded in tECM-supplemented scaffold exhibited significantly increased proliferation and tenogenic differentiation. The presence of tECM also greatly suppressed the osteogenic differentiation of hASCs triggered by uniaxial tension. In addition, tECM-supplemented constructs displayed enhanced mechanical strength, accompanied by reduced expression and activity of MMPs in the seeded hASCs, indicating a regulatory activity of tECM in cell-mediated scaffold remodeling. These findings support the utility of tECM in creating bio-functional scaffolds for tendon tissue engineering.     

Titania-hydroxyapatite nanocomposite coatings support human mesenchymal stem cells osteogenic differentiation

In addition to mechanical and chemical stability, the third design goal of the ideal bone-implant coating is the ability to support osteogenic differentiation of mesenchymal stem cells (MSCs). Plasma-sprayed TiO(2)-based bone-implant coatings exhibit excellent long-term mechanical properties, but their applications in bone implants are limited by their bioinertness. We have successfully produced a TiO(2) nanostructured (grain size <50 nm) based coating charged with 10% wt hydroxyapatite (TiO(2)-HA) sprayed by high-velocity oxy-fuel. On Ti64 substrates, the novel TiO(2)-HA coating bond 153× stronger and has a cohesive strength 4× higher than HA coatings. The HA micro- and nano-sized particles covering the TiO(2)-HA coating surface are chemically bound to the TiO(2) coating matrix, producing chemically stable coatings under high mechanical solicitations. In this study, we elucidated the TiO(2)-HA nanocomposite coating surface chemistry, and in vitro osteoinductive potential by culturing human MSCs (hMSCs) in basal and in osteogenic medium (hMSC-ob). We assessed the following hMSCs and hMSC-ob parameters over a 3-week period: (i) proliferation; (ii) cytoskeleton organization and cell-substrate adhesion; (iii) coating-cellular interaction morphology and growth; and (iv) cellular mineralization. The TiO(2) -HA nanocomposite coatings demonstrated 3× higher hydrophilicity than HA coatings, a TiO(2)-nanostructured surface in addition to the chemically bound HA micron- and nano-sized rod to the surface. hMSCs and hMSC-ob demonstrated increased proliferation and osteoblastic differentiation on the nanostructured TiO(2)-HA coatings, suggesting the TiO(2)-HA coatings nanostructure surface properties induce osteogenic differentiation of hMSC and support hMSC-ob osteogenic potential better than our current golden standard HA coating.     

Human urine-derived stem cells can be induced into osteogenic lineage by silicate bioceramics via activation of the Wnt/β-catenin signaling pathway

Human urine-derived stem cells (USCs) have great application potential for cytotherapy as they can be obtained by non-invasive and simple methods. Silicate bioceramics, including calcium silicate (CS), can stimulate osteogenic differentiation of stem cells. However, the effects of silicate bioceramics on osteogenic differentiation of USCs have not been reported. In this study, at first, we investigated the effects of CS ion extracts on proliferation and osteogenic differentiation of USCs, as well as the related mechanism. CS particles were incorporated into poly (lactic-co-glycolic acid) (PLGA) to obtain PLGA/CS composite scaffolds. USCs were then seeded onto these scaffolds, which were subsequently transplanted into nude mice to analyze the osteogenic differentiation of USCs and mineralization of extracellular matrix formed by USCs in vivo. The results showed that CS ion extracts significantly enhanced cell proliferation, alkaline phosphatase (ALP) activity, calcium deposition, and expression of certain osteoblast-related genes and proteins. In addition, cardamonin, a Wnt/β-catenin signaling inhibitor, reduced the stimulatory effects of CS ion extracts on osteogenic differentiation of USCs, indicating that the observed osteogenic differentiation of USCs induced by CS ion extracts involves Wnt/β-catenin signaling pathway. Furthermore, histological analysis showed that PLGA/CS composite scaffolds significantly enhanced the osteogenic differentiation of USCs in vivo. Taken together, these results suggest the therapeutic potential of combining USCs and PLGA/CS scaffolds in bone tissue regeneration.     

Characterization of zinc-releasing three-dimensional bioactive glass scaffolds and their effect on human adipose stem cell proliferation and osteogenic differentiation

While the addition of zinc ions to bioactive ceramics has been shown to enhance the proliferation and osteogenic differentiation of osteoblast-like cells, contradictory results have been found. Therefore, the effect of zinc-releasing ceramics on cell proliferation and differentiation into osteogenic lineages requires further clarification. The aim of this study was to evaluate the effects of zinc addition on the degradation profile of three-dimensional bioactive glass scaffold, and on the proliferation and osteogenesis of human adipose stem cells (hASCs) in these scaffolds. Bioactive glass scaffolds containing Na₂O, K₂O, MgO, CaO, B₂O₃, TiO₂, P₂O₅ and SiO₂ were prepared. The degradation was evaluated by weight loss measurement, scanning electron microscopy and elemental analysis. The degradation profile of bioactive glass was shown to slow down with the addition of zinc. Qualitative live/dead staining showed that zinc addition to bioactive glass inhibits cell spreading and proliferation of hASCs. However, zinc addition had no significant effect on DNA content, alkaline phosphatase activity and osteopontin concentration of hASCs when measured quantitatively. Our results suggest that the possible stimulatory effect of addition of zinc on hASC proliferation and osteogenesis was not detected because addition of zinc slowed down the degradation rate of the studied bioactive glass scaffolds.     

Nonintegrating knockdown and customized scaffold design enhances human adipose-derived stem cells in skeletal repair

An urgent need exists in clinical medicine for suitable alternatives to available techniques for bone tissue repair. Human adipose-derived stem cells (hASCs) represent a readily available, autogenous cell source with well-documented in vivo osteogenic potential. In this article, we manipulated Noggin expression levels in hASCs using lentiviral and nonintegrating minicircle short hairpin ribonucleic acid (shRNA) methodologies in vitro and in vivo to enhance hASC osteogenesis. Human ASCs with Noggin knockdown showed significantly increased bone morphogenetic protein (BMP) signaling and osteogenic differentiation both in vitro and in vivo, and when placed onto a BMP-releasing scaffold embedded with lentiviral Noggin shRNA particles, hASCs more rapidly healed mouse calvarial defects. This study therefore suggests that genetic targeting of hASCs combined with custom scaffold design can optimize hASCs for skeletal regenerative medicine.     

The stimulation of osteogenic differentiation of human adipose-derived stem cells by ionic products from akermanite dissolution via activation of the ERK pathway

Our previous study indicates that akermanite, a type of Ca-, Mg-, Si-containing bioceramic, can promote the osteogenic differentiation of hASCs. To elucidate the underlying mechanism, we investigated the effect of the extract from akermanite, on proliferation and osteogenic differentiation of hASCs. The original extract was obtained at 200 mg akermanite/ml LG-DMEM and further diluted with LG-DMEM. The final extracts were denoted as 1/2, 1/4, 1/8, 1/16, and 1/32 extracts based on the concentrations of the original extract. The LDH assay and live/dead stain were used to reveal the cytotoxicity of the different extracts on hASCs, while the DNA assay was carried out to quantitatively evaluate the proliferation of cells after being cultured with the extracts for 1, 3 and 7 days. Flow cytometry for cell cycle analysis was carried out on cells cultured in two media (GM and 1/2 extract) in order to further analyze the effect of the extract on cell proliferation behaviors. Osteogenic differentiation of hASCs cultured in the extracts was detected by ALP expression and calcium deposition, and further confirmed by real-time PCR analysis. It was shown that Ca, Mg and Si ions in the extract could suppress the LDH release and proliferation of hASCs, whereas promote their osteogenic differentiation. Such effects were concentration-dependent with the 1/4 extract (Ca 2.36 mM, Mg 1.11 mM, Si 1.03 mM) being the optimum in promoting the osteogenic differentiation of hASCs. An immediate increase in ERK was observed in cells cultured in the 1/4 extract and such osteogenic differentiation of hASCs promoted by released ions could be blocked by MEK1-specific inhibitor, PD98059. Briefly, Ca, Mg and Si ions extracted from akermanite in the concentrations of 2.36, 1.11, 1.03 mM, respectively, could facilitate the osteogenic differentiation of hASCs via an ERK pathway, and suppress the proliferation of hASCs without significant cytotoxicity.     

Hyaluronan expression as a significant prognostic factor in patients with malignant peripheral nerve sheath tumors

Hyaluronan (HA) regulates malignant tumor growth, invasion, and metastasis. However, few studies have focused on the roles of HA in tumorigenicity in malignant peripheral nerve sheath tumors (MPNST). In this study, we sought to clarify the prognostic value of HA in patients with MPNST. Specimens obtained from 15 patients with neurofibroma and 30 with MPNST were subjected to HA staining and scored as three grades. Protein expressions of HA synthase 1–3 were examined in the 22 MPNST tissue samples available. Statistically higher HA positivity was observed in MPNST as compared with neurofibroma (P = 0.020). The univariate analysis revealed that increased HA expression, age, neurofibromatosis type 1 (NF1) status, large tumor size, and histological grade were significantly associated with reduced overall survival of patients with MPNST; while increased HA expression, NF1 status, tumor size, and histological grade were correlated with disease-free survival. However, HA synthase 1–3 expression related to neither overall survival nor disease-free survival of these patients. In multivariate analysis, large tumor size (P = 0.022) was an independent prognostic factor for overall survival, and HA expression (P = 0.028) and tumor size (P = 0.002) were independent prognostic factors for disease-free survival. Statistically higher levels of HA in the human MPNST cells were observed compared with neurofibroma cells in vitro. Our results demonstrate that HA expression can be a useful marker in differentiating MPNST from neurofibroma, and in identifying patients with a poor prognosis. Hyaluronan-targeting therapy for patients with MPNST may have potential as a therapeutic tool.     

The osteogenic differentiation of SSEA-4 sub-population of human adipose derived stem cells using silicate nanoplatelets

How to surpass in vitro stem cell differentiation, reducing cell manipulation, and lead the in situ regeneration process after transplantation, remains to be unraveled in bone tissue engineering (bTE). Recently, we showed that the combination of human bone marrow stromal cells with bioactive silicate nanoplatelets (sNPs) promotes the osteogenic differentiation without the use of standard osteogenic inductors. Even more, using SSEA-4⁺ cell-subpopulations (SSEA-4⁺hASCs) residing within the adipose tissue, as a single-cellular source to obtain relevant cell types for bone regeneration, was also proposed. Herein, sNPs were used to promote the osteogenic differentiation of SSEA-4⁺hASCs. The interactions between SSEA-4⁺hASCs and sNPs, namely the internalization pathway and effect on cells osteogenic differentiation, were evaluated. SNPs below 100 μg/mL showed high cytocompatibility and fast internalization via clathrin-mediated pathway. SNPs triggered an overexpression of osteogenic-related markers (RUNX2, osteopontin, osteocalcin) accompanied by increased alkaline phosphatase activity and deposition of a predominantly collagen-type I matrix. Consequently, a robust matrix mineralization was achieved, covering >90% of the culturing surface area. Overall, we demonstrated the high osteogenic differentiation potential of SSEA-4⁺hASCs, further enhanced by the addition of sNPs in a dose dependent manner. This strategy endorses the combination of an adipose-derived cell-subpopulation with inorganic compounds to achieve bone matrix-analogs with clinical relevance.     

人骨髓间质干细胞与新型可降解材料生物相容性的实验研究

目的：本研究利用人骨髓间质干细胞（MSC）的增殖与分化潜能作为指标，对可降解偏磷酸钙（dCMP）材料和羟基磷灰石（HA）材料的生物相容性进行体外研究。 方法： 通过扫描电镜观察MSC在dCMP表面粘附的情况，并利用ICP和IC分析dCMP和HA的降解产物元素含量，同时采用FACS、ALP活性检测及ARS等方法对降解产物的毒性效应进行检测。 结果： dCMP对MSC的增殖有促进作用，且不影响MSC的成骨分化进程及分化后的矿化功能；而HA对MSC的成骨分化进程无影响，但对MSC的增殖和成骨分化后的矿化功能均有抑制作用。 结论： dCMP的生物相容性较HA为佳，更适合作为骨替代材料。     

A bioactive triphasic ceramic-coated hydroxyapatite promotes proliferation and osteogenic differentiation of human bone marrow stromal cells

Hydroxyapatite (HA) ceramics are widely used as bone graft substitutes because of their biocompatibility and osteoconductivity. However, to enhance the success of therapeutic application, many efforts are undertaken to improve the bioactivity of HA. We have developed a triphasic, silica-containing ceramic-coated hydroxyapatite (HASi) and evaluated its performance as a scaffold for cell-based tissue engineering applications. Human bone marrow stromal cells (hBMSCs) were seeded on both HASi and HA scaffolds and cultured with and without osteogenic supplements for a period of 4 weeks. Cellular responses were determined in vitro in terms of cell adhesion, viability, proliferation, and osteogenic differentiation, where both materials exhibited excellent cytocompatibility. Nevertheless, an enhanced rate of cell proliferation and higher levels of both alkaline phosphatase expression and activity were observed for cells cultured on HASi with osteogenic supplements. These findings indicate that the bioactivity of HA endowed with a silica-containing coating has definitely influenced the cellular activity, projecting HASi as a suitable candidate material for bone regenerative therapy.     

Embroidered and Surface Modified Polycaprolactone-Co-Lactide Scaffolds as Bone Substitute: <Emphasis Type="Italic">In Vitro</Emphasis> Characterization

The aim of this study was to evaluate an embroidered polycaprolactone-co-lactide (trade name PCL) scaffold for the application in bone tissue engineering. The surface of the PCL scaffolds was hydrolyzed with NaOH and coated with collagen I (coll I) and chondroitin sulfate (CS). It was investigated if a change of the surface properties and the application of coll I and CS could promote cell adhesion, proliferation, and osteogenic differentiation of human mesenchymal stem cells (hMSC). The porosity (80%) and pore size (0.2–1 mm) of the scaffold could be controlled by embroidery technique and should be suitable for bone ingrowth. The treatment with NaOH made the polymer surface more hydrophilic (water contact angle dropped to 25%), enhanced the coll I adsorption (up to 15%) and the cell attachment (two times). The coll I coated scaffold improved cell attachment and proliferation (three times). CS, as part of the artificial matrix, could induce the osteogenic differentiation of hMSC without other differentiation additives. The investigated scaffolds could act not just as temporary matrix for cell migration, proliferation, and differentiation in bone tissue engineering but also have a great potential as bioartificial bone substitute.     

Novel hydroxyapatite/chitosan bilayered scaffold for osteochondral tissue-engineering applications: Scaffold design and its performance when seeded with goat bone marrow stromal cells

Recent studies suggest that bone marrow stromal cells are a potential source of osteoblasts and chondrocytes and can be used to regenerate damaged tissues using a tissue-engineering (TE) approach. However, these strategies require the use of an appropriate scaffold architecture that can support the formation de novo of either bone and cartilage tissue, or both, as in the case of osteochondral defects. The later has been attracting a great deal of attention since it is considered a difficult goal to achieve. This work consisted on developing novel hydroxyapatite/chitosan (HA/CS) bilayered scaffold by combining a sintering and a freeze-drying technique, and aims to show the potential of such type of scaffolds for being used in TE of osteochondral defects. The developed HA/CS bilayered scaffolds were characterized by Fourier transform infra-red spectroscopy, X-ray diffraction analysis, micro-computed tomography, and scanning electron microscopy (SEM). Additionally, the mechanical properties of HA/CS bilayered scaffolds were assessed under compression. In vitro tests were also carried out, in order to study the water-uptake and weight loss profile of the HA/CS bilayered scaffolds. This was done by means of soaking the scaffolds into a phosphate buffered saline for 1 up to 30 days. The intrinsic cytotoxicity of the HA scaffolds and HA/CS bilayered scaffolds extract fluids was investigated by carrying out a cellular viability assay (MTS test) using Mouse fibroblastic-like cells. Results have shown that materials do not exert any cytotoxic effect. Complementarily, in vitro (phase I) cell culture studies were carried out to evaluate the capacity of HA and CS layers to separately, support the growth and differentiation of goat marrow stromal cells (GBMCs) into osteoblasts and chondrocytes, respectively. Cell adhesion and morphology were analysed by SEM while the cell viability and proliferation were assessed by MTS test and DNA quantification. The chondrogenic differentiation of GBMCs was evaluated measuring the glucosaminoglycans synthesis. Data showed that GBMCs were able to adhere, proliferate and osteogenic differentiation was evaluated by alkaline phosphatase activity and immunocytochemistry assays after 14 days in osteogenic medium and into chondrocytes after 21 days in culture with chondrogenic medium. The obtained results concerning the physicochemical and biological properties of the developed HA/CS bilayered scaffolds, show that these constructs exhibit great potential for their use in TE strategies leading to the formation of adequate tissue substitutes for the regeneration of osteochondral defects.     

Differential osteogenic activity of osteoprogenitor cells on HA and TCP/HA scaffold of tissue engineered bone

Biomaterial, an essential component of tissue engineering, serves as a scaffold for cell attachment, proliferation, and differentiation; provides the three dimensional (3D) structure and, in some applications, the mechanical strength required for the engineered tissue. Both synthetic and naturally occurring calcium phosphate based biomaterial have been used as bone fillers or bone extenders in orthopedic and reconstructive surgeries. This study aims to evaluate two popular calcium phosphate based biomaterial i.e., hydroxyapatite (HA) and tricalcium phosphate/hydroxyapatite (TCP/HA) granules as scaffold materials in bone tissue engineering. In our strategy for constructing tissue engineered bone, human osteoprogenitor cells derived from periosteum were incorporated with human plasma-derived fibrin and seeded onto HA or TCP/HA forming 3D tissue constructs and further maintained in osteogenic medium for 4 weeks to induce osteogenic differentiation. Constructs were subsequently implanted intramuscularly in nude mice for 8 weeks after which mice were euthanized and constructs harvested for evaluation. The differential cell response to the biomaterial (HA or TCP/HA) adopted as scaffold was illustrated by the histology of undecalcified constructs and evaluation using SEM and TEM. Both HA and TCP/HA constructs showed evidence of cell proliferation, calcium deposition, and collagen bundle formation albeit lesser in the former. Our findings demonstrated that TCP/HA is superior between the two in early bone formation and hence is the scaffold material of choice in bone tissue engineering.