Enzyme-Mediated Nerve Growth Factor Release from Nanofibers Using Gelatin Microspheres.

Spinal cord injury is a complex environment, with many conflicting growth factors present at different times throughout the injury timeline. Delivery of multiple growth factors has received mixed results, highlighting a need to consider the timing of delivery for possibly antagonistic growth factors. Cell-mediated degradation of delivery vehicles for delayed release of growth factors offers an attractive way to exploit the highly active immune response in the spinal cord injury environment. In this study, growth factor-loaded gelatin microspheres (GMS) combined with methacrylated hyaluronic acid (MeHA) were electrospun to create GMS fibers (GMSF) for delayed release of growth factors (GFs). GMS were successfully combined with MeHA while electrospinning, with an average fiber diameter of 365 ± 10 nm and 44% ± 8% fiber alignment. GMSF with nerve growth factor (NGF) was tested on dissociated chick dorsal root ganglia cells. We further tested the effect of M1 macrophage-conditioned media (M1CM) to simulate macrophage invasion after spinal cord injury for cell-mediated degradation. We hypothesized that neurons grown on GMSF with loaded NGF would exhibit longer neurites in M1CM, showing a release of functional NGF, as compared with controls. GMSF in M1CM was significantly different from MeHA in serum-free media (SFM) and M0-conditioned media (M0CM), as well as GMSF in M0CM (p < 0.05). Moreover, GMSF + NGF in all media conditions were significantly different from MeHA in SFM and M0CM (p < 0.05). The goal of this study was to develop a biomaterial system where drug delivery is triggered by immune response, allowing for more control and longer exposure to encapsulated drugs. The spinal cord injury microenvironment is known to have a robust immune response, making this immune-medicated drug release system particularly significant for directed repair.

Chitosan-based scaffolds as drug delivery systems in bone tissue engineering.

The bone tissue engineering approach for treating large bone defects becomes necessary when the tissue damage surpasses the threshold of the inherent regenerative ability of the human body. A myriad of natural biodegradable polymers and scaffold fabrication techniques have emerged in the last decade. Chitosan (CS) is especially attractive as a bone scaffold material to support cell attachment and proliferation and mineralization of the bone matrix. The primary amino groups in CS are responsible for properties such as controlled drug release, mucoadhesion, in situ gelation, and transfection. CS-based smart drug delivery scaffolds that respond to environmental stimuli have been reported to have a localized sustained delivery of drugs in the large bone defect area. This review outlines the recent advances in the fabrication of CS-based scaffolds as a pharmaceutical carrier to deliver drugs such as antibiotics, growth factors, nucleic acids, and phenolic compounds for bone tissue regeneration.

Enhanced photodegradation of rifampicin and co-trimoxazole by ZnO/ZnMn2O4/ZnS-PVA and its genotoxicity studies on Allium cepa.

Oxygen vacancies and its associated defect states have a great influence on the electronic and structural aspects of semiconductor photocatalysts, yet there is paucity of investigations about the influence of the defect states on their photocatalytic properties. Herein, this study reports the hierarchical fabrication of oxygen vacancy enriched ZnO/ZnMn2O4/ZnS-PVA nanocomposite (NCs) for the enhanced photodegradation of rifampicin and co-trimoxazole. The formation of lattice expansion induced oxygen vacancies and its associated Urbach tail energy, and n-p-n heterojunction-based S-scheme charge transfer path synergistically contributed to the boosted photocatalytic performance of the as prepared NCs. The photocatalytic performance of the nanomaterial towards rifampicin and co-trimoxazole has been determined to be 80% and 90% under visible light irradiation, respectively. Furthermore, various operating parameters including the concentration of NCs and drug, pH and interference of various ions have been evaluated. The degraded product intermediates have been elucidated by GC-MS analysis. The toxicity of the as-prepared nanomaterials has been evaluated by treating the samples with root tips of Allium cepa, where the NCs was found to be non-toxic. The study provides a new-fangled insight on the preparation and fabrication of non-toxic and defect rich nanomaterials which may help stimulate this area of research.

Sunlit expeditious visible light-mediated photo-fenton degradation of ciprofloxacin by exfoliation of NiCo2O4 and Zn0·3Fe2·7O4 over g-C3N4 matrix: A brief insight on degradation mechanism, degraded product toxicity, and genotoxic evaluation in Allium cepa.

Pharmaceutical pollutant in the environmental water bodies has become a major concern, which causes adverse effect to aquatic entities. This study provides an incisive insight on the photocatalytic degradation of ciprofloxacin (CIP) and the development of rationally engineered g-C3N4-NiCo2O4-Zn0.3Fe2·7O4 nanocomposite for boosted photocatalytic performance under visible light irradiation. The g-C3N4-NiCo2O4-Zn0.3Fe2·7O4 nanocomposite was synthesized via ultrasonication-assisted hydrothermal method. The characterization of the as-prepared material was evaluated by XPS, SEM, HR-TEM, PL, FT-IR, EIS, ESR, XRD, BET, and UV-Vis DRS techniques. Furthermore, the effect of catalytic dosage, drug dosage, and pH changes was explored, where g-C3N4-NiCo2O4-Zn0.3Fe2·7O4-10% unveiled excellent visible light photo-Fenton degradation of 92% for CIP at 140 min. The hydroxyl radicals (OH.) served as the predominant radical species on the photodegradation of CIP, which was confirmed by performing a radical scavenging test. Furthermore, the degradation efficiency was determined by six consecutive cycle tests, where the nanomaterial exhibited excellent stability with 98.5% reusable efficiency. The degradation of CIP was further scrutinized by GC-MS analysis, where the degraded intermediate products and the possible pathway were elucidated. The degraded product toxicity was determined by ECOSAR program, where the degraded products haven't exhibited any considerable toxic effects. In addition, the genotoxicity of the nanomaterial was determined by treating them with root tips of A. cepa, where it was found to be non-toxic. Here, the prepared g-C3N4-NiCo2O4-Zn0.3Fe2·7O4 nanocomposite (CNZ NCs) shows eco-friendly and excellent photo-Fenton activity for environmental applications.

A novel SPR based Fe@Ag core-shell nanosphere entrapped on starch matrix an optical probe for sensing of mercury(II) ion: A nanomolar detection, wide pH range and real water sample application.

Recent trends in nanotechnology paved a way for the development of detection systems for heavy metals, toxins and environmental pollutants. The present study focused on Hg2+ detection by a core shell Fe@Ag-starch nanosphere phenylalanine conjugate. The characterization of core shell Fe@Ag-starch nanosphere was performed by using TEM, zetasizer, particlesize analyzer, UV-visible absorption spectrophotometer, EDAX, FTIR and TGA. The NPs showed λmax at 408 nm. The effective diameter of synthesized nanosphere was 37 ± 2 nm and it possessed the surfaces charge of -36.12 ± 2.5 mV. The Fe@Ag-starch-phenylalanine conjugate reacted with Hg2+, the yellow colour of the nanosphere phenylalanine conjugate became colourless. The real water sample was collected and the amount of Hg2+ was calculated by using the prepared nanosphere. The detection of Hg2+ at different conditions including various saline concentrations, temperature and pH were also studied and the detection was found to be effective at 40 °C, pH 5 and 0.1% of saline concentration. The LOD of Hg2+ ions by Fe@Ag-starch nanosphere were calculated to be 1.84 nM. The influence of other metal ions present in the analyte did not show any interference on Hg2+ detection. In addition, the photocatalytic and antibacterial activities of Fe@Ag-starch nanosphere were also studied. The study confirmed that the core shell nanosphere can also be used for environmental cleanup and disinfection.

An Enigmatic Elevation of Troponin in a Patient With Seizures.

A 64-year-old African American male, with past medical history of hypertension, depression, and seizure disorder, presented with an episode of generalized tonic-clonic seizure. He was treated for seizures, and after 48 hours seizure-free, the patient started complaining of chest tightness and troponin levels were found to be 34.71 ng/mL. No evidence of myocardial infarction was found after extensive diagnostic workup, including cardiac catheterization. We suspect alternative causes of elevated troponin including post-seizure and transient takosubo cardiomyopathy.

Mechanical, topographical and chemical cues combined with physical therapy for peripheral nerve injuries.

Aim: The aim of this paper is to evaluate biomaterial cues combined with physical therapy (PT) on functional recovery in a rat sciatic nerve injury model. Materials & methods: Nerve growth conduits were filled with longitudinally aligned hyaluronic acid fibers and microspheres containing neurotrophic factor (growth factor [GF]). All animals received behavior and functional testing throughout the study, which concluded with measurement of compound muscle action potentials and contractile force of the gastrocnemius muscle. Results & conclusion: Including GF improved recovery of gross motor function and increased sensory pain sensation. During the 4 weeks that animals participated in PT, these groups showed higher static sciatic index scores. Including GF and PT has the potential to improve clinical outcomes following peripheral nerve injury.

Heparin-hyaluronic acid nanofibers for growth factor sequestration in spinal cord repair.

Growth factor (GF) delivery is a common strategy for spinal cord injury repair, however, GF degradation can impede long-term therapies. GF sequestration via heparin is known to protect bioactivity after delivery. We tested two heparin modifications, methacrylated heparin and thiolated heparin, and electrospun these with methacrylated hyaluronic acid (MeHA) to form HepMAHA and HepSHHA nanofibers. For loaded conditions, MeHA, HepMAHA, and HepSHHA fibers were incubated with soluble basic fibroblast growth factor (bFGF) or nerve growth factor (NGF) and rinsed with PBS. Control groups were hydrated in PBS. L929 fibroblast proliferation was analyzed after 24 hr of culture in either growth media or bFGF-supplemented media. Dissociated chick dorsal root ganglia neurites were measured after 3 days of cell culture in serum free media (SFM) or NGF-supplemented SFM (SFM + NGF). In growth media, fibroblast proliferation was significantly increased in loaded HepMAHA (α < .05) compared to other groups. In SFM, loaded HepMAHA had the longest average neurite length compared to all other groups. In SFM + NGF, HepMAHA and HepSHHA had increased neurite lengths compared to MeHA, regardless of loading (α < .01), suggesting active sequestration of soluble NGF. HepMAHA is a promising biomaterial for sequestering released GFs in a spinal cord injury environment and will be combined with GF filled microspheres for future studies.

Advances in Molecular Mechanisms of Wheat Allergenicity in Animal Models: A Comprehensive Review.

The prevalence of wheat allergy has reached significant levels in many countries. Therefore, wheat is a major global food safety and public health issue. Animal models serve as critical tools to advance the understanding of the mechanisms of wheat allergenicity to develop preventive and control methods. A comprehensive review on the molecular mechanisms of wheat allergenicity using animal models is unavailable at present. There were two major objectives of this study: To identify the lessons that animal models have taught us regarding the molecular mechanisms of wheat allergenicity and to identify the strengths, challenges, and future prospects of animal models in basic and applied wheat allergy research. Using the PubMed and Google Scholar databases, we retrieved and critically analyzed the relevant articles and excluded celiac disease and non-celiac gluten sensitivity. Our analysis shows that animal models can provide insight into the IgE epitope structure of wheat allergens, effects of detergents and other chemicals on wheat allergenicity, and the role of genetics, microbiome, and food processing in wheat allergy. Although animal models have inherent limitations, they are critical to advance knowledge on the molecular mechanisms of wheat allergenicity. They can also serve as highly useful pre-clinical testing tools to develop safer genetically modified wheat, hypoallergenic wheat products, novel pharmaceuticals, and vaccines.

T-blocker: a simple and robust probe-free quantitative PCR assay to detect somatic mutations down to 0.1% frequency.

We have developed a simple and robust probe-free quantitative PCR (qPCR) assay method that can detect minor mutant alleles with a frequency as low as 0.1% in a heterogeneous sample by introducing a novel T-blocker concept to the allele-specific PCR method. Four new KRAS and BRAF mutation detection assays were developed and their performance was demonstrated by testing a large number of replicates, utilizing a customized PCR protocol. Highly efficient and specific mutant amplification in conjunction with selective wild-type suppression by the T-blocker concept enabled 0.1% detection sensitivity using the intercalating dye-based qPCR chemistry instead of more complex target-specific dye-labeled probes. Excellent consistency in sensitivity and specificity of the T-blocker assay concept was demonstrated.

Biomaterial Cues to Direct a Pro-regenerative Phenotype in Macrophages and Schwann Cells.

Following peripheral nerve injury (PNI), inflammatory cues impede repair. We have previously demonstrated that spinal cord matrix (SCM) proteins and hyaluronic acid (HA) nanofibers mitigate chondroitin sulfate proteoglycan (CSPG) inhibition and promote growth in peripheral neurons. In this study, we evaluated the effects of a characteristic CSPG, chondroitin sulfate A (CSA), SCM, and HA fibers on macrophages and Schwann cells (SCs). We hypothesized that our cues would accelerate the macrophages' return to rest following classical activation (M1/pro-inflammatory) with lipopolysaccharide (LPS; 1 µg/mL) and would accelerate the transformation of SCs from an immature state following injury to a mature/pro-myelinating phenotype. LPS stimulation of the macrophages caused upregulation of inducible nitric oxide synthase (iNOS; M1 gene) and led to significantly increased cell area and decreased circularity. However, the SCM and HA nanofibers mitigated this effect, significantly reducing iNOS expression. SCs on the fibers had significantly reduced area and increased elongation. These morphological changes may have polarized the cells leading to decreased GFAP (immature gene) and increased Oct6 and Krox 20 (promyelin genes) expression. Antibody arrays were used to measure relative levels of inflammatory cytokines released by the cells. The arrays confirmed that anti-inflammatory cytokines are released from the cells when cultured with our biomaterial cues and helped identify targets for future investigation including vascular endothelial growth factor (VEGF), interleukin (IL)-10, monocyte colony stimulating factor (M-CSF) from the macrophages, Agrin, ciliary neurotrophic factor (CNTF), tissue inhibitor metalloproteinases (TIMPs)-1 from SCs, and IL-2 from both cell types. In conclusion, these results suggest that our biomaterial cues have pro-regenerative effects on both cell types and if combined may trigger cells toward regenerative programs.

Combining growth factor releasing microspheres within aligned nanofibers enhances neurite outgrowth.

Current treatments for peripheral nerve injuries include autografts, the gold standard, and commercially available nerve growth conduits (NGCs). Autografts have several drawbacks including donor site morbidity and nerve size mismatch, which lead to incomplete recovery. However, even with these drawbacks, autografts work better then commercially available NGCs that lack sufficient cues to promote complete regeneration. This study evaluated a combination of biomaterial components that can be added to the hollow internal space of a NGC to promote and direct nerve regeneration; specifically, mechanical, chemical, and topographical cues. Methacrylated hyaluronic acid (MeHA, mechanical cue) is electrospun into aligned fibers (topographical cue), with poly-lactic-co-glycolic acid microspheres to deliver nerve growth factor (NGF, chemical cue). The properties of the scaffold were evaluated under physiological conditions using environmental scanning electron microscopy and mechanical testing. The resulting scaffolds have hydrated porosities of 35-55% and Young's modulus in the range of 0.43-2.86 MPa. Enzyme-linked immunosorbent assay showed that NGF is released from the microspheres for up to 4 weeks. Dorsal root ganglia (DRG) neurons showed that the released NGF is bioactive. DRG testing on the scaffolds also showed that the combination of NGF released from the microspheres and the aligned nanofibers significantly enhanced neurite outgrowth. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 17-25, 2018.

Positive and negative cues for modulating neurite dynamics and receptor expression.

Many current peripheral nerve repair strategies focus on delivering positive, growth promoting cues (e.g. extracellular matrix, ECM) while eliminating negative, growth inhibiting cues (e.g. chondroitin sulfate proteoglycans, CSPGs) at the injury site. We hypothesized that recapitulating the positive and negative cues of the peripheral nerve injury microenvironment would improve regeneration. First, we tested the effects of a characteristic CSPG, chondroitin sulfate A (CSA) on neurite dynamics of dissociated chick embryo dorsal root ganglion (DRG) neurons using time lapse video microscopy. DRG growth was recorded on different adhesive substrates, including a novel, porcine-derived spinal cord matrix (SCM). The SCM significantly increased frequency of neurite extension coordinated by a significant reduction in the neurites' time spent stalled. The SCM also mitigated inhibitory effects of CSA, producing longer neurites than the controls without CSA treatment. Next we aimed to elucidate receptors involved in mediating this behavior by testing the ability of CSA to upregulate cell-substrate binding receptors using flow cytometry. Our results showed a significant increase in syndecan-3 receptor expression in neurons treated with CSA. Furthermore, syndecans would most likely bind to the sulfated glycosaminoglycans measured in the SCM. Finally, we evaluated neurite growth on biomaterial scaffolds featuring CSA and SCM cues. Our results showed significantly increased neurite outgrowth on electrospun hyaluronic acid fibers with SCM and low levels of CSA. Higher incorporation of CSA maintained its inhibitory properties. Future work will evaluate coupling CSPGs with growth-permissive ECM to assess the combined effect on neurite outgrowth.

Psychosocial factors associated with reverse smoking: A qualitative research.

OBJECTIVES: Reverse smoking is a peculiar form of smoking in which the smoker puts the lit end of the cigarette into the mouth and then inhales the smoke. There may be many predisposing factors that influence an individual to cultivate this habit, of which psychosocial habits could be the predominating factor. Hence, the present study was undertaken to evaluate the psychosocial factors that influence an individual to undertake this peculiar habit of reverse smoking. MATERIALS AND METHODS: A total of 128 habitual reverse smokers were included in the study, out of which 121 were females and 7 were males. A pretested open-ended questionnaire was used for data collection. Data was collected by direct interview method. Snowball sampling technique was employed in collecting the information regarding regular reverse smokers. Interviews were continued until new information did not provide further insights into the categories. The people who could not understand verbal commands and questions and who did not give an informed consent were excluded from the study. Statistical analysis was done using MS Office Excel using Chi-square test of Goodness of fit. RESULTS: In contrast to the conventional smokers, various new reasons were identified for starting reverse smoking, of which the most important was that they had learned this habit from their mothers. This was followed by other reasons such as peer pressure, friendship, and cold climatic conditions. CONCLUSION: This study provided an insight into the various factors that could influence an individual to take up this peculiar habit of reverse smoking.

Role played by Prx1-dependent extracellular matrix properties in vascular smooth muscle development in embryonic lungs.

Although there are many studies focusing on the molecular pathways underlying lung vascular morphogenesis, the extracellular matrix (ECM)-dependent regulation of mesenchymal cell differentiation in vascular smooth muscle development needs better understanding. In this study, we demonstrate that the paired related homeobox gene transcription factor Prx1 maintains the elastic ECM properties, which are essential for vascular smooth muscle precursor cell differentiation. We have found that Prx1(null) mouse lungs exhibit defective vascular smooth muscle development, downregulated elastic ECM expression, and compromised transforming growth factor (TGF)-ß localization and signaling. Further characterization of ECM properties using decellularized lung ECM scaffolds derived from Prx1 mice demonstrated that Prx1 is required to maintain lung ECM stiffness. The results of cell culture using stiffness-controlled 2-D and 3-D synthetic substrates confirmed that Prx1-dependent ECM stiffness is essential for promotion of smooth muscle precursor differentiation for effective TGF-ß stimulation. Supporting these results, both decellularized Prx1(null) lung ECM and Prx1(WT) (wild type) ECM scaffolds with blocked TGF-ß failed to support mesenchymal cell to 3-D smooth muscle cell differentiation. These results suggest a novel ECM-dependent regulatory pathway of lung vascular development wherein Prx1 regulates lung vascular smooth muscle precursor development by coordinating the ECM biophysical and biochemical properties.

An Adjuvant-Free Mouse Model of Transdermal Sensitization and Oral Elicitation of Anaphylaxis to Shellfish.

BACKGROUND: Shellfish (SF) allergy is a leading cause of systemic anaphylaxis in humans. An adjuvant-free mouse model to evaluate allergenicity and oral anaphylaxis to SF is currently unavailable. Here, we tested the hypothesis that transdermal exposure (TDE) to SF protein extract (SFPE) not only elicits a systemic allergic immune response but also will clinically sensitize mice for oral anaphylaxis. METHODS: Adult BALB/c female mice (6-8 weeks of age) were exposed to saline or SFPE once a week for 4 weeks using a transdermal sensitization method. Systemic SF-specific IgE, IgG1 and IgG2a and total (t)IgE responses were measured using ELISA. Systemic anaphylaxis upon oral SFPE administration was assessed according to clinical symptoms and the hypothermia shock response (HSR). Using individual mouse data, the correlation between the readouts of allergenicity was determined using Pearson's analysis. Spleen-cell IL-4 and IFN-x03B3; responses were determined using primary cell culture and ELISA. RESULTS: TDE to SFPE resulted in marked systemic specific (s)IgE, tIgE, IgG1 and IgG2a responses. Oral challenge with SFPE in sensitized mice (but not controls) elicited systemic anaphylactic clinical reactions and HSR. A strong correlation was observed between sIgE, tIgE and HSR. Spleen cells isolated from allergic mice (but not controls) exhibited memory IL-4 and IFN-x03B3; cytokine responses. CONCLUSION: We report a novel adjuvant-free mouse model of SF allergy with robust quantifiable and correlated readouts of allergenicity that may be used in basic biomedical, preclinical and applied food/nutrition research on SF allergy.

Electrospinning growth factor releasing microspheres into fibrous scaffolds.

This procedure describes a method to fabricate a multifaceted substrate to direct nerve cell growth. This system incorporates mechanical, topographical, adhesive and chemical signals. Mechanical properties are controlled by the type of material used to fabricate the electrospun fibers. In this protocol we use 30% methacrylated Hyaluronic Acid (HA), which has a tensile modulus of ~500 Pa, to produce a soft fibrous scaffold. Electrospinning on to a rotating mandrel produces aligned fibers to create a topographical cue. Adhesion is achieved by coating the scaffold with fibronectin. The primary challenge addressed herein is providing a chemical signal throughout the depth of the scaffold for extended periods. This procedure describes fabricating poly(lactic-co-glycolic acid) (PLGA) microspheres that contain Nerve Growth Factor (NGF) and directly impregnating the scaffold with these microspheres during the electrospinning process. Due to the harsh production environment, including high sheer forces and electrical charges, protein viability is measured after production. The system provides protein release for over 60 days and has been shown to promote primary nerve cell growth.

Directed migration in neural tissue engineering.

Directed cell migration is particularly important in neural tissue engineering, where the goal is to direct neurons and support cells across injured nerve gaps. Investigation of the gradients present in the body during development provides an approach to guiding cells in peripheral and central nervous system tissue, but many different types of gradients and patterns can accomplish directed migration. The focus of this review is to describe current research paradigms in neural tissue gradients and review their effectiveness for directed migration. The review explores directed migration achieved through the use of chemical, adhesive, mechanical, topographical, and electrical types of gradients. Few studies investigate combined gradients, though it is known that a combination of therapies is necessary for reconnection of neuronal circuitry. To date, there has been no systematic review of gradient approaches to neural tissue engineering. By looking at effectiveness of various scaffold cue presentation and methods to combine these strategies, the potential for nerve repair is increased.

Jagged1 immobilization to an osteoconductive polymer activates the Notch signaling pathway and induces osteogenesis.

Treatment of nonunion fractures is a significant problem. Common therapeutics, including autologous bone grafts and bone morphogenetic proteins, show well-established limitations. Therefore, a need persists for the identification of novel clinical therapies to promote healing. The Notch signaling pathway regulates bone development. Clinically, loss-of-function mutations to the Notch ligand Jagged1 decrease bone mass and increase fracture risk. Jagged1 is also the most highly upregulated ligand during fracture repair, identifying it as a potential target to promote bone formation. Therefore, the objective of this study was to develop a clinically translatable construct comprised of Jagged1 and an osteoconductive scaffold, and characterize its activity in human mesenchymal stem cells (hMSC). We first evaluated the effects of Jagged1 directly immobilized to a novel poly(ß-amino ester) relative to indirect coupling via antibody. Direct was more effective at activating hMSC Notch target gene expression and osteogenic activity. We then found that directly immobilized Jagged1 constructs induced osteoblast differentiation. This is the first study to demonstrate that Jagged1 delivery transiently activates Notch signaling and increases osteogenesis. A positive correlation was found between Jagged1-induced Notch and osteogenic expression. Collectively, these results indicate that Jagged1 coupled to an osteogenic biomaterial could promote bone tissue formation during fracture healing.

Fiber alignment directs cell motility over chemotactic gradients.

The ability of tissue engineered scaffolds to direct cell behavior is paramount for scaffold design. Cell migration can be directed by various methods including chemical, adhesive, mechanical, and topographical cues. Electrospinning has emerged as a popular method to control topography and create fibrous scaffolds similar to that found in extracellular matrix. One major hurdle is limited cell infiltration and several studies have explored methods to alter electrospun materials to increase scaffold porosity; however, uniform cell distributions within scaffolds is still limited. Towards this, we investigated the motility of HUVECs on a model system of electrospun hyaluronic acid fibers under a gradient of VEGF and found that topographical cues dominate cell motility direction. Using time-lapse microscopy, cell aspect ratio, and migration angle were measured; cells were directed in a chemical gradient and/or on aligned electrospun fibers. Measurements of the persistence time demonstrated an additive effect of the chemical gradient and fiber alignment. However, when fibers were aligned perpendicular to a chemical gradient, cells were directed by fiber alignment and there was no effect of the chemical gradient. These results suggest that topographical cues may be more influential than chemical cues in directing cell motility and should be considered in material design.