Human Bone-Marrow-Derived Stem-Cell-Seeded 3D Chitosan-Gelatin-Genipin Scaffolds Show Enhanced Extracellular Matrix Mineralization When Cultured under a Perfusion Flow in Osteogenic Medium

Tissue-engineered bone tissue grafts are a promising alternative to the more conventional use of natural donor bone grafts. However, choosing an appropriate biomaterial/scaffold to sustain cell survival, proliferation, and differentiation in a 3D environment remains one of the most critical issues in this domain. Recently, chitosan/gelatin/genipin (CGG) hybrid scaffolds have been proven as a more suitable environment to induce osteogenic commitment in undifferentiated cells when doped with graphene oxide (GO). Some concern is, however, raised towards the use of graphene and graphene-related material in medical applications. The purpose of this work was thus to check if the osteogenic potential of CGG scaffolds without added GO could be increased by improving the medium diffusion in a 3D culture of differentiating cells. To this aim, the level of extracellular matrix (ECM) mineralization was evaluated in human bone-marrow-derived stem cell (hBMSC)-seeded 3D CGG scaffolds upon culture under a perfusion flow in a dedicated custom-made bioreactor system. One week after initiating dynamic culture, histological/histochemical evaluations of CGG scaffolds were carried out to analyze the early osteogenic commitment of the culture. The analyses show the enhanced ECM mineralization of the 3D perfused culture compared to the static counterpart. The results of this investigation reveal a new perspective on more efficient clinical applications of CGG scaffolds without added GO.

Peripheral blood mononuclear cells contribute to myogenesis in a 3D bioengineered system of bone marrow mesenchymal stem cells and myoblasts

In this work, a 3D environment obtained using fibrin scaffold and two cell populations, such as bone marrow-derived mesenchymal stem cells (BM-MSCs), and primary skeletal muscle cells (SkMs), was assembled. Peripheral blood mononuclear cells (PBMCs) fraction obtained after blood filtration with HemaTrate^® filter was then added to the 3D culture system to explore their influence on myogenesis. The best cell ratio into a 3D fibrin hydrogel was 1:1 (BM-MSCs plus SkMs:PBMCs) when cultured in a perfusion bioreactor; indeed, excellent viability and myogenic event induction were observed. Myogenic genes were significantly overexpressed when cultured with PBMCs, such as MyoD1 of 118-fold at day 14 and Desmin 6-fold at day 21. Desmin and Myosin Heavy Chain were also detected at protein level by immunostaining along the culture. Moreover, the presence of PBMCs in 3D culture induced a significant downregulation of pro-inflammatory cytokine gene expression, such as IL6. This smart biomimetic environment can be an excellent tool for investigation of cellular crosstalk and PBMC influence on myogenic processes.

Myogenic commitment of human stem cells by myoblasts Co-culture: a static vs. a dynamic approach

An in-vitro model of human bone marrow mesenchymal stem cells (hBM-MSCs) myogenic commitment by synergic effect of a differentiation media coupled with human primary skeletal myoblasts (hSkMs) co-culture was developed adopting both conventional static co-seeding and perfused culture systems. Static co-seeding provided a notable outcome in terms of gene expression with a significant increase of Desmin (141-fold) and Myosin heavy chain II (MYH2, 32-fold) at day 21, clearly detected also by semi-quantitative immunofluorescence. Under perfusion conditions, myogenic induction ability of hSkMs on hBM-MSCs was exerted by paracrine effect with an excellent gene overexpression and immunofluorescence detection of MYH2 protein; furthermore, due to the dynamic cell culture in separate wells, western blot data were acquired confirming a successful cell commitment at day 14. A significant increase of anti-inflammatory cytokine gene expression, including IL-10 and IL-4 (15-fold and 11-fold, respectively) at day 14, with respect to the pro-inflammatory cytokines IL-12A (7-fold at day 21) and IL-1β (1.4-fold at day 7) was also detected during dynamic culture, confirming the immunomodulatory activity of hBM-MSCs along with commitment events. The present study opens interesting perspectives on the use of dynamic culture based on perfusion as a versatile tool to study myogenic events and paracrine cross-talk compared to the simple co-seeding static culture.

Fiber Thickness and Porosity Control in a Biopolymer Scaffold 3D Printed through a Converted Commercial FDM Device

3D printing has opened exciting new opportunities for the in vitro fabrication of biocompatible hybrid pseudo-tissues. Technologies based on additive manufacturing herald a near future when patients will receive therapies delivering functional tissue substitutes for the repair of their musculoskeletal tissue defects. In particular, bone tissue engineering (BTE) might extensively benefit from such an approach. However, designing an optimal 3D scaffold with adequate stiffness and biodegradability properties also guaranteeing the correct cell adhesion, proliferation, and differentiation, is still a challenge. The aim of this work was the rewiring of a commercial fuse deposition modeling (FDM) 3D printer into a 3D bioplotter, aiming at obtaining scaffold fiber thickness and porosity control during its manufacturing. Although it is well-established that FDM is a fast and low-price technology, the high temperatures required for printing lead to limitations in the biomaterials that can be used. In our hands, modifying the printing head of the FDM device with a custom-made holder has allowed to print hydrogels commonly used for embedding living cells. The results highlight a good resolution, reproducibility and repeatability of alginate/gelatin scaffolds obtained via our custom 3D bioplotter prototype, showing a viable strategy to equip a small-medium laboratory with an instrument for manufacturing good-quality 3D scaffolds for cell culture and tissue engineering applications.

Design of a custom-made device for real-time optical measurement of differential mineral concentrations in three-dimensional scaffolds for bone tissue engineering

Monitoring bone tissue engineered (TEed) constructs during their maturation is important to ensure the quality of applied protocols. Several destructive, mainly histochemical, methods are conventionally used to this aim, requiring the sacrifice of the investigated samples. This implies (i) to plan several scaffold replicates, (ii) expensive and time consuming procedures and (iii) to infer the maturity level of a given tissue construct from a cognate replica. To solve these issues, non-destructive techniques such as light spectroscopy-based methods have been reported to be useful. Here, a miniaturized and inexpensive custom-made spectrometer device is proposed to enable the non-destructive analysis of hydrogel scaffolds. Testing involved samples with a differential amount of calcium salt. When compared to a reference standard device, this custom-made spectrometer demonstrates the ability to perform measurements without requiring elaborate sample preparation and/or a complex instrumentation. This preliminary study shows the feasibility of light spectroscopy-based methods as useful for the non-destructive analysis of TEed constructs. Based on these results, this custom-made spectrometer device appears as a useful option to perform real-time/in-line analysis. Finally, this device can be considered as a component that can be easily integrated on board of recently prototyped bioreactor systems, for the monitoring of TEed constructs during their conditioning.

3D Biomimetic Scaffold for Growth Factor Controlled Delivery: An In-Vitro Study of Tenogenic Events on Wharton's Jelly Mesenchymal Stem Cells

The present work described a bio-functionalized 3D fibrous construct, as an interactive teno-inductive graft model to study tenogenic potential events of human mesenchymal stem cells collected from Wharton’s Jelly (hWJ-MSCs). The 3D-biomimetic and bioresorbable scaffold was functionalized with nanocarriers for the local controlled delivery of a teno-inductive factor, i.e., the human Growth Differentiation factor 5 (hGDF-5). Significant results in terms of gene expression were obtained. Namely, the up-regulation of Scleraxis (350-fold, p ≤ 0.05), type I Collagen (8-fold), Decorin (2.5-fold), and Tenascin-C (1.3-fold) was detected at day 14; on the other hand, when hGDF-5 was supplemented in the external medium only (in absence of nanocarriers), a limited effect on gene expression was evident. Teno-inductive environment also induced pro-inflammatory, (IL-6 (1.6-fold), TNF (45-fold, p ≤ 0.001), and IL-12A (1.4-fold)), and anti-inflammatory (IL-10 (120-fold) and TGF-β1 (1.8-fold)) cytokine expression upregulation at day 14. The presented 3D construct opens perspectives for the study of drug controlled delivery devices to promote teno-regenerative events.

Development of an electrical impedance tomography set-up for the quantification of mineralization in biopolymer scaffolds

Objective. 3D cell cultures are becoming a fundamental resource forin-vitrostudies, as they mimic more closelyin-vivobehavior. The analysis of these constructs, however, generally rely on destructive techniques, that prevent the monitoring over time of the same construct, thus increasing the results variability and the resources needed for each experiment.Approach. In this work, we focus on mineralization, a crucial process during maturation of artificial bone models, and propose electrical impedance tomography (EIT) as an alternative non-destructive approach. In particular, we discuss the development of an integrated hardware/software system capable of acquiring experimental data from 3D scaffolds and reconstructing the corresponding conductivity maps. We also show how the same software can test how the measurement is affected by biological features such as scaffold shrinking during the culture.Main results. An initial validation, comprising the acquisition of both a non-conductive phantom and alginate/gelatin scaffolds with known calcium content will be presented, together with thein-silicostudy of a cell-induced mineralization process. This analysis will allow for an initial verification of the systems functionality while limiting the effects of biological variability due to cell number and activity.Significance. Our results show the potential of EIT for the non-destructive quantification of matrix mineralization in 3D scaffolds, and open to the possible long term monitoring of this fundamental hallmark of osteogenic differentiation in hybrid tissue engineered constructs.

Chondrogenic Commitment of Human Bone Marrow Mesenchymal Stem Cells in a Perfused Collagen Hydrogel Functionalized with hTGF-β1-Releasing PLGA Microcarrier

Tissue engineering strategies can be relevant for cartilage repair and regeneration. A collagen matrix was functionalized with the addition of poly-lactic-co-glycolic acid microcarriers (PLGA-MCs) carrying a human Transforming Growth Factor β1 (hTFG-β1) payload, to provide a 3D biomimetic environment with the capacity to direct stem cell commitment towards a chondrogenic phenotype. PLGA-MCs (mean size 3 ± 0.9 μm) were prepared via supercritical emulsion extraction technology and tailored to sustain delivery of payload into the collagen hydrogel for 21 days. PLGA-MCs were coseeded with human Bone Marrow Mesenchymal Stem Cells (hBM-MSCs) in the collagen matrix. Chondrogenic induction was suggested when dynamic perfusion was applied as indicated by transcriptional upregulation of COL2A1 gene (5-fold; p < 0.01) and downregulation of COL1A1 (0.07-fold; p < 0.05) and COL3A1 (0.11-fold; p < 0.05) genes, at day 16, as monitored by qRT-PCR. Histological and quantitative-immunofluorescence (qIF) analysis confirmed cell activity by remodeling the synthetic extracellular matrix when cultured in perfused conditions. Static constructs lacked evidence of chondrogenic specific gene overexpression, which was probably due to a reduced mass exchange, as determined by 3D system Finite Element Modelling (FEM) analysis. Proinflammatory (IL-6, TNF, IL-12A, IL-1β) and anti-inflammatory (IL-10, TGF-β1) cytokine gene expression by hBM-MSC was observed only in dynamic culture (TNF and IL-1β 10-fold, p < 0.001; TGF-β1 4-fold, p < 0.01 at Day 16) confirming the cells’ immunomodulatory activity mainly in relation to their commitment and not due to the synthetic environment. This study supports the use of 3D hydrogel scaffolds, equipped for growth factor controlled delivery, as tissue engineered models for the study of in vitro chondrogenic differentiation and opens clinical perspectives for injectable collagen-based advanced therapy systems.

Perfusion Flow Enhances Viability and Migratory Phenotype in 3D-Cultured Breast Cancer Cells

Conventional 2D cell culture, a traditional tool in pre-clinical studies, can hardly be regarded as a representation of a natural cell microenvironment. In this respect, it might result in altered cellular behaviors. To overcome such a limitation, different approaches have been tested to conduct more representative in vitro studies. In particular, the use of 3D cell culture introduces variables, such as cell-cell and cell-extracellular matrix interactions; cell features such as survival, proliferation and migration are consequently influenced. For an example, an enhanced drug resistance and increased invasiveness are shown by cancer cells when cultured in 3D versus 2D conventional culture models. In this setting however, non-uniform cell distribution and biological behaviors appear throughout the scaffold, due to reduced diffusion of oxygen and nutrients. Perfusion in bioreactor systems can be used to improve medium transport. In this line of reasoning, this study proposes a breast cancer cell culture model sustained by an integrated approach that couples a 3D environment and a fluid perfusion. This model improves viability and uniformness of cell distribution, while inducing morphological, functional and molecular cancer cell remodeling.

Tendon and Cytokine Marker Expression by Human Bone Marrow Mesenchymal Stem Cells in a Hyaluronate/Poly-Lactic-Co-Glycolic Acid (PLGA)/Fibrin Three-Dimensional (3D) Scaffold

We developed a (three-dimensional) 3D scaffold, we named HY-FIB, incorporating a force-transmission band of braided hyaluronate embedded in a cell localizing fibrin hydrogel and poly-lactic-co-glycolic acid (PLGA) nanocarriers as transient components for growth factor controlled delivery. The tenogenic supporting capacity of HY-FIB on human-Bone Marrow Mesenchymal Stem Cells (hBM-MSCs) was explored under static conditions and under bioreactor-induced cyclic strain conditions. HY-FIB elasticity enabled to deliver a mean shear stress of 0.09 Pa for 4 h/day. Tendon and cytokine marker expression by hBM-MSCs were studied. Results: hBM-MSCs embedded in HY-FIB and subjected to mechanical stimulation, resulted in a typical tenogenic phenotype, as indicated by type 1 Collagen fiber immunofluorescence. RT-qPCR showed an increase of type 1 Collagen, scleraxis, and decorin gene expression (3-fold, 1600-fold, and 3-fold, respectively, at day 11) in dynamic conditions. Cells also showed pro-inflammatory (IL-6, TNF, IL-12A, IL-1β) and anti-inflammatory (IL-10, TGF-β1) cytokine gene expressions, with a significant increase of anti-inflammatory cytokines in dynamic conditions (IL-10 and TGF-β1 300-fold and 4-fold, respectively, at day 11). Mechanical signaling, conveyed by HY-FIB to hBM-MSCs, promoted tenogenic gene markers expression and a pro-repair cytokine balance. The results provide strong evidence in support of the HY-FIB system and its interaction with cells and its potential for use as a predictive in vitro model.

Analysis of Intracellular Magnesium and Mineral Depositions during Osteogenic Commitment of 3D Cultured Saos2 Cells

In this study, we explore the behaviour of intracellular magnesium during bone phenotype modulation in a 3D cell model built to mimic osteogenesis. In addition, we measured the amount of magnesium in the mineral depositions generated during osteogenic induction. A two-fold increase of intracellular magnesium content was found, both at three and seven days from the induction of differentiation. By X-ray microscopy, we characterized the morphology and chemical composition of the mineral depositions secreted by 3D cultured differentiated cells finding a marked co-localization of Mg with P at seven days of differentiation. This is the first experimental evidence on the presence of Mg in the mineral depositions generated during biomineralization, suggesting that Mg incorporation occurs during the bone forming process. In conclusion, this study on the one hand attests to an evident involvement of Mg in the process of cell differentiation, and, on the other hand, indicates that its multifaceted role needs further investigation.

A dynamic culture platform enhances the efficiency of the 3D HUVEC-based tube formation assay

Cell-based in vitro biological models traditionally use monolayer cell cultures grown over plastic surfaces bathing in static media. Higher fidelity to a natural biological tissue is expected to result from growing the cells in a three-dimensional (3D) matrix. However, due to the decreased rate of diffusion inherent to increased distances within a tridimensional space, proper fluidic conditions are needed in this setting to better approximate a physiological environment. To this aim, we here propose a prototypal dynamic cell culture platform for the automatic medium replacement, via periodic perfusion flow, in a human umbilical vein endothelial cell (HUVECs) culture seeded in a Geltrex™ matrix. A state-of-the-art angiogenesis assay performed in these dynamic conditions showed sizable effects with respect to conventional static control cultures, with significantly enhanced pro-(dual antiplatelet therapy [DAPT]) and anti-(EDTA) angiogenic compound activity. In particular, dynamic culture conditions (a) enhance the 3D-organization of HUVECs into microtubule structure; (b) accelerate and improve endothelial tube formation by HUVECs in the presence of DAPT; (c) are able to completely revert the blocking effects of EDTA. These evidence emphasize the need of setting proper fluidic conditions for a better approximation of a physiological environment as an appropriate evolution of current cell culture paradigms.

A standalone bioreactor system to deliver compressive load under perfusion flow to hBMSC-seeded 3D chitosan-graphene templates

The availability of engineered biological tissues holds great potential for both clinical applications and basic research in a life science laboratory. A prototype standalone perfusion/compression bioreactor system was proposed to address the osteogenic commitment of stem cells seeded onboard of 3D chitosan-graphene (CHT/G) templates. Testing involved the coordinated administration of a 1 mL/min medium flow rate together with dynamic compression (1% strain at 1 Hz; applied twice daily for 30 min) for one week. When compared to traditional static culture conditions, the application of perfusion and compression stimuli to human bone marrow stem cells using the 3D CHT/G template scaffold induced a sizable effect. After using the dynamic culture protocol, there was evidence of a larger number of viable cells within the inner core of the scaffold and of enhanced extracellular matrix mineralization. These observations show that our novel device would be suitable for addressing and investigating the osteogenic phenotype commitment of stem cells, for both potential clinical applications and basic research.

Mechanical Actuation Systems for the Phenotype Commitment of Stem Cell-Based Tendon and Ligament Tissue Substitutes

High tensile forces transmitted by tendons and ligaments make them susceptible to tearing or complete rupture. The present standard reparative technique is the surgical implantation of auto- or allografts, which often undergo failure.Currently, different cell types and biomaterials are used to design tissue engineered substitutes. Mechanical stimulation driven by dedicated devices can precondition these constructs to a remarkable degree, mimicking the local in vivo environment. A large number of dynamic culture instruments have been developed and many appealing results collected. Of the cells that have been used, tendon stem cells are the most promising for a reliable stretch-induced tenogenesis, but their reduced availability represents a serious limitation to upscaled production. Biomaterials used for scaffold fabrication include both biological molecules and synthetic polymers, the latter being improved by nanotechnologies which reproduce the architecture of native tendons. In addition to cell type and scaffold material, other variables which must be defined in mechanostimulation protocols are the amplitude, frequency, duration and direction of the applied strain. The ideal conditions seem to be those producing intermittent tension rather than continuous loading. In any case, all physical parameters must be adapted to the specific response of the cells used and the tensile properties of the scaffold. Tendon/ligament grafts in animals usually have the advantage of mechanical preconditioning, especially when uniaxial cyclic forces are applied to cells engineered into natural or decellularized scaffolds. However, due to the scarcity of in vivo research, standard protocols still need to be defined for clinical applications.

Isolation of a novel gene, TSP50, by a hypomethylated DNA fragment in human breast cancer

A novel gene, testes-specific protease 50 (TSP50), was isolated from a human testes cDNA library by using a genomic DNA probe, BR50. BR50 was isolated by a modified representational difference analysis (RDA) technique due to its hypomethylated feature in a breast cancer biopsy. This altered DNA methylation status was also detected by BR50 in other breast and some ovarian cancer tissues. The TSP50 gene product is a homologue to several human proteases, which indicates that it may encode a protease-like protein. Northern analysis of 16 different types of normal human tissues suggests that TSP50 was highly and specifically expressed in human testes, which indicates that it might possess a unique biological function(s) in that organ. Methylation status analysis in normal human testes and other tissues showed a correlation between DNA methylation and gene expression. Most importantly, reverse transcription-PCR analysis of 18 paired breast cancer tissues found that in 28% of the cancer samples, the TSP50 gene was differentially expressed. The possibility that TSP50 may be an oncogene is presently under investigation.

Pelvic control following external beam radiation for surgical stage I endometrial adenocarcinoma

PURPOSE

To determine if postoperative external pelvic radiation (EBRT), without vaginal brachytherapy, is sufficient to prevent vaginal cuff and pelvic recurrences in patients with surgical Stage I endometrial adenocarcinoma (ACA).

METHODS AND MATERIALS

The records of 122 patients with surgical Stage I endometrial cancer were reviewed. There were 87 patients with ACA who received EBRT alone and are the subject of this study. Their radiation records were reviewed. All patients underwent exploration, total abdominal hysterectomy, and bilateral salpingo-oophorectomy (TAH BSO), and pelvic and paraaortic lymph node sampling. They were staged according to the FIGO 1988 surgical staging system recommendations. Postoperatively, pelvic EBRT was administered by megavoltage equipment using four fields, to a total dose of 45 to 50.4 Gy. Actuarial survival and disease free survival were calculated according to Kaplan-Meier Method.

RESULTS

Twenty-seven patients with Stage IA Grade 1 or 2 ACA with less than one-third myometrial invasion, who did not receive EBRT, and eight patients with histology other than adenocarcinoma (i.e., serous papillary, mucinous, etc.) were not included in the study. For the remaining 87 patients who are in the study group, the median follow-up was 52 months (range: 12-82 months). The 5-year overall survival for these 87 patients was 92%, with a disease-free survival of 83%. There were no tumor recurrences in the upper vagina or in the pelvis. Two patients developed small bowel obstruction (no surgery required), and one patient developed chronic enteritis.

CONCLUSION

Adjuvant external pelvic radiation, without vaginal brachytherapy, prevents pelvic and vaginal cuff recurrences in surgical Stage I endometrial ACA.

Pharmacokinetic evaluation of zeniplatin in humans

Zeniplatin, a more water-soluble organoplatinum than cisplatin, was evaluated for clinical pharmacology in the context of a phase II trial in previously treated patients with ovarian carcinoma. A total of 12 patients were given zeniplatin at 120 mg/m2 by rapid intravenous infusion over 90 min, with both blood and urine being sampled. All platinum moieties were analyzed in whole blood, plasma, plasma ultrafiltrate, and urine by atomic absorption, and free zeniplatin was analyzed in plasma ultrafiltrate by specific high-performance liquid chromatography (HPLC). In a comparison of the platinum-time concentration curve, AUC (area under the curve) values indicated that approximately 90% of platinum moieties were bound to circulating plasma proteins. There was no evidence of drug accumulation after repetitive dosing. The terminal half-life (t1/2) of this drug in plasma ultrafiltrate (3.7-7.2 h.) as measured by HPLC was slightly longer than that of carboplatin, whereas total platinum moieties in plasma displayed a long t1/2 (124-154 h). Approximately 60% of platinum moieties could be recovered in the urine within 24 h. These findings suggest that zeniplatin has a pharmacokinetic profile similar to that of carboplatin.

Comprehensive management including interstitial brachytherapy for locally advanced or recurrent gynecologic malignancies

Radical therapy for locally advanced or recurrent gynecologic malignancies (LARGM) may include interstitial brachytherapy (IB) when intracavitary brachytherapy is impossible or inadequate and external beam teletherapy would be limited by surrounding normal tissue tolerance. Sixteen women received IB as all or part of their treatment at North Shore University Hospital for the treatment of locally advanced primary or recurrent tumors of gynecologic origin from May 1988 through September 1990. Primary sites included the vulva (3), vagina (2), cervix (7), and endometrium (4). Radiosensitizing chemotherapy was used in 8 patients. With a median follow-up of 23 months (range, 12-44 months), 11 patients (69%) have experienced continuous local control of their tumor and 4 patients (25%) have experienced severe complications. While significant risks may attend the use of IB, IB is an integral part of management for select patients with LARGM.

Use of cisplatin for elderly patients

The ageing of the population has resulted in a greater emphasis on cancer treatment effects in elderly patients. This population has often had arbitrary dose modification of chemotherapy owing to fear of excessive side-effects. A review was undertaken to evaluate cisplatin toxicity in patients of 70 years of age or older. Thirty-four patients were evaluated. Their mean age was 72.8 years and 85.3% were women. Fourteen of 34 (41%) patients completed the planned therapy. Treatment was terminated because of disease progression (35%), renal toxicity (9%) and non-renal toxicity (15%). Our conclusion is that cisplatin can safely be administered to elderly patients. Arbitrary dose modification or elimination of cisplatin from a treatment programme on the grounds of patient age alone is not justified.

Acute peripheral arterial occlusion associated with surgery for gynecologic cancer

Four cases are described of acute peripheral arterial occlusion associated with surgery for gynecologic cancer during the 5 years 1979 to 1983 at the University of Miami, Jackson Memorial Hospital Center. No such cases were recorded during the preceding 5 years. The probable underlying etiologic factors are discussed and recommendations made regarding the evaluation and management of such patients.