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Study Objective: To assess the feasibility of a noncontact radio sensor as an objective measurement tool to study postoperative recovery from endometriosis surgery.Design: Prospective cohort pilot study.Setting: Center for minimally invasive gynecologic surgery at an academically affiliated community hospital in conjunction with in-home monitoring.Patients: Patients aged above 18 years who sleep independently and were scheduled to have laparoscopy for the diagnosis and treatment of suspected endometriosis.Interventions: A wireless, noncontact sensor, Emerald, was installed in the subjects' home and used to capture physiologic signals without body contact. The device captured objective data about the patients' movement and sleep in their home for 5 weeks before surgery and approximately 5 weeks postoperatively. The subjects were concurrently asked to complete a daily pain assessment using a numeric rating scale and a free text survey about their daily symptoms.Measurements and Main Results: Three women aged 23 years to 39 years and with mild to moderate endometriosis participated in the study. Emerald-derived sleep and wake times were contextualized and corroborated by select participant comments from retrospective surveys. In addition, self-reported pain levels and 1 sleep variable, sleep onset to deep sleep time, showed a significant (p <.01), positive correlation with next-day-pain scores in all 3 subjects: r = 0.45, 0.50, and 0.55. In other words, the longer it took the subject to go from sleep onset to deep sleep, the higher their pain score the following day.Conclusion: A patient's experience with pain is challenging to meaningfully quantify. This study highlights Emerald's unique ability to capture objective data in both preoperative functioning and postoperative recovery in an endometriosis population. The utility of this uniquely objective data for the clinician-patient relationship is just beginning to be explored. [ABSTRACT FROM AUTHOR]

Because tissues are characterized by a well-defined three-dimensional arrangement of cells, tissue engineering scaffolds that facilitate the organization and differentiation of new tissue will have improved performance in comparison to scaffolds that only provide surfaces for cell attachment and growth. We hypothesize that instructions for cells can be incorporated into tissue engineering scaffolds by patterning the scaffold''s architecture and surface chemistry. Our goals for the presented work were to collect data about cell response to three-dimensional, porous scaffolds with uniformly modified surfaces chemistries, and to demonstrate patterning of cell response by patterning surface chemistry.Our system was osteoblast response to poly(l-lactide-co-glycolide) scaffolds modified with poly(ethylene oxide) (PEO). Scaffolds were fabricated using the Three-Dimensional Printing™ (3DP™) process which has control over scaffolds properties to a resolution of ∼100 μm in all three dimensions. At higher PEO concentrations, adhesion, growth rates, and migration of rat osteoblasts were reduced; alkaline phosphate activity was increased, and cells were less spread and had microvilli. Patterned regions of low and high cell adhesion were demonstrated on scaffolds fabricated with 1 mm thick stripes of PEO and non-PEO regions. [Copyright &y& Elsevier]

Abstract: Biomimetic scaffolds have been proposed as a means to facilitate tissue regeneration by multi-potent stromal cells (MSCs). Effective scaffold colonization requires a control of multiple MSC responses including survival, proliferation, differentiation, and migration. As MSC migration is relatively unstudied in this context, we present here a multi-level approach to its understanding and control, integratively tuning cell speed and directional persistence to achieve maximal mean free path (MFP) of migration. This approach employs data-driven computational modeling to ascertain small molecule drug treatments that can enhance MFP on a given materials substratum. Using poly(methyl methacrylate)-graft-poly(ethylene oxide) polymer surfaces tethered with epidermal growth factor (tEGF) and systematically adsorbed with fibronectin, vitronectin, or collagen-I to present hTERT-immortalized human MSCs with growth factor and extracellular matrix cues, we measured cell motility properties along with signaling activities of EGFR, ERK, Akt, and FAK on 19 different substrate conditions. Speed was consistent on collagen/tEGF substrates, but low associated directional persistence limited MFP. Decision tree modeling successfully predicted that ERK inhibition should enhance MFP on collagen/tEGF substrates by increasing persistence. Thus, we demonstrated a two-tiered approach to control MSC migration: materials-based “coarse-graining” complemented by small molecule “fine-tuning”. [Copyright &y& Elsevier]

Three-dimensional micro-physiological in vitro representations of human tissues and organs are emerging as important models of human pathophysiology and stand to make a significant impact on the process of drug discovery and development. An enduring need is to create microvascular networks within such 3D models, particularly for tissues with high metabolic demand such as the liver, pancreas, and the central nervous system. Here we report a facile approach to drive angiogenesis in nascent 3D culture models by embedding degradable hydrogel microbeads coated with induced pluripotent stem cell-derived endothelial cells (MB-iPSC-ECs) in a dense epithelial tissue. Specifically, we describe an approach to optimize microbead scaffold cues, independent of the external environment, by evaluating the iPSC-EC to microbead adhesion properties and how they influence the propensity of cells to both coat microbeads uniformly and undergo sprouting angiogenesis. We encapsulated MB-iPSC-ECs in PEG hydrogels, systematically varied the relative concentration of integrin-targeting peptide motifs in the microbead and surrounding environment, and found that an optimal microbead scaffold ligand regime of 0.1–0.25 mM promotes iPSC-EC monolayer formation and subsequent invasion into the synthetic matrix. We used these results to predict the regime of adhesion ligand required to promote angiogenesis of MB-iPSC-ECs in a co-culture hepatocarcinoma (HEPG2) microtissue model. This modular degradable microbead platform has the potential to promote angiogenic sprouting, which may ultimately support vascularization of a variety of cell-dense tissues. [ABSTRACT FROM AUTHOR]

Active matrix metalloproteases (MMPs) play a significant role in the pathogenesis of many diseases including osteoarthritis (OA), which involves progressive proteolytic degradation of cartilage. Clinical success of OA interventions that target MMPs has been limited by a lack of information about the presence and activity of specific disease-related proteases. We therefore developed a chemoproteomics approach based on MS to characterize the release and activity of MMPs in an in vitro model of the early inflammatory phase of posttraumatic OA (PTOA). We designed and synthesized chemical activity-based probes (ABPs) to identify active MMPs in bovine cartilage explants cultured for 30 days with the proinflammatory cytokine, interleukin- 1α. Using these probes in an activity-based protein profiling- multidimensional identification technology (ABPP-MudPIT) approach, we identified active MMP-1, -2, -3, -7, -9, -12, and -13 in the medium after 10 days of culture, the time at which irreversible proteolysis of the collagen network in the explant was detected using proteolytic activation of FRET-quenched MMP substrates. Total MMP levels were quantified by shotgun proteomics, which, taken with ABPP-MudPIT data, indicated the presence of predominantly inactive MMPs in the culture medium. The selectivity of the ABPP-MudPIT approach was further validated by detection of specific endogenous MMPs activated de novo with 4-aminophenylmurcuric acetate. The utility of the new ABPP-MudPIT approach for detecting molecular biomarkers of PTOA disease initiation and potential targets for therapeutics motivates possible application in other diseases involving MMP activity. [ABSTRACT FROM AUTHOR]

In vitro human small intestine models play a crucial part in preclinical drug development. Although conventional 2D systems possess many advantages, such as facile accessibility and high-throughput capability, they can also provide misleading results due to their relatively poor recapitulation of in vivo physiology. Significant progress has recently been made in developing 3D human small intestine models, suggesting that more-reliable preclinical results could be obtained by recreating the 3D intestinal microenvironment in vitro . Although there are still many challenges, 3D human small intestine models have the potential to facilitate drug screening and drug development. [ABSTRACT FROM AUTHOR]

Highlights: [•] Reliable in vitro models for human disease are needed. [•] Human cell-based models including iPS cell-based models are emerging. [•] Biomimetic matrices and substrates are crucial to recapitulate microenvironment. [•] Microfluidics and microfabrication technologies enable dynamic organ models. [•] Systems biology and multidisciplinary approaches are crucial to drug discovery. [Copyright &y& Elsevier]

Large-scale expansion of highly functional adult human mesenchymal stem cells (aMSCs) remains technologically challenging as aMSCs lose self renewal capacity and multipotency during traditional long-term culture and their quality/quantity declines with donor age and disease. Identification of culture conditions enabling prolonged expansion and rejuvenation would have dramatic impact in regenerative medicine. aMSC-derived decellularized extracellular matrix (ECM) has been shown to provide such microenvironment which promotes MSC self renewal and “stemness”. Since previous studies have demonstrated superior proliferation and osteogenic potential of human fetal MSCs (fMSCs), we hypothesize that their ECM may promote expansion of clinically relevant aMSCs. We demonstrated that aMSCs were more proliferative (∼1.6×) on fMSC-derived ECM than aMSC-derived ECMs and traditional tissue culture wares (TCPS). These aMSCs were smaller and more uniform in size (median ± interquartile range: 15.5 ± 4.1 μm versus 17.2 ± 5.0 μm and 15.5 ± 4.1 μm for aMSC ECM and TCPS respectively), exhibited the necessary biomarker signatures, and stained positive for osteogenic, adipogenic and chondrogenic expressions; indications that they maintained multipotency during culture. Furthermore, fMSC ECM improved the proliferation (∼2.2×), size (19.6 ± 11.9 μm vs 30.2 ± 14.5 μm) and differentiation potential in late-passaged aMSCs compared to TCPS. In conclusion, we have established fMSC ECM as a promising cell culture platform for ex vivo expansion of aMSCs. [ABSTRACT FROM AUTHOR]

Prodomains of A disintegrin and metalloproteinase (ADAM) metallopeptidases can act as highly specific intra- and intermolecular inhibitors of ADAM catalytic activity. The mouse ADAM9 prodomain (proA9; amino acids 24-204), expressed and characterized from Escherichia coli, is a competitive inhibitor of human ADAM9 catalytic/disintegrin domain with an overall inhibition constant of 280 ± 34 nm and high specificity toward ADAM9. In SY5Y neuroblastoma cells overexpressing amyloid precursor protein, proA9 treatment reduces the amount of endogenous ADAM10 enzyme in the medium while increasing membrane-bound ADAM10, as shown both by Western and activity assays with selective fluorescent peptide substrates using proteolytic activity matrix analysis. An increase in membrane-bound ADAM10 generates higher levels of soluble amyloid precursor protein α in the medium, whereas soluble amyloid precursor protein β levels are decreased, demonstrating that inhibition of ADAM9 increases α-secretase activity on the cell membrane. Quantification of physiological ADAM10 substrates by a proteomic approach revealed that substrates, such as epidermal growth factor (EGF), HER2, osteoactivin, and CD40-ligand, are increased in the medium of BT474 breast tumor cells that were incubated with proA9, demonstrating that the regulation of ADAM10 by ADAM9 applies for many ADAM10 substrates. Taken together, our results demonstrate that ADAM10 activity is regulated by inhibition of ADAM9, and this regulation may be used to control shedding of amyloid precursor protein by enhancing α-secretase activity, a key regulatory step in the etiology of Alzheimer disease. [ABSTRACT FROM AUTHOR]

The ErbB receptor family is dysregulated in many cancers, and its therapeutic manipulation by targeted antibodies and kinase inhibitors has resulted in effective chemotherapies. However, many malignancies remain refractory to current interventions. We describe a new approach that directs ErbB receptor interactions, resulting in biased signaling and phenotypes. Due to known receptor-ligand affinities and the necessity of ErbB receptors to dimerize to signal, bivalent ligands, formed by the synthetic linkage of two neuregulin-1β (NRG) moieties, two epidermal growth factor (EGF) moieties, or an EGF and a NRG moiety, can potentially drive homotypic receptor interactions and diminish formation of HER2-containing heterodimers, which are implicated in many malignancies and are a prevalent outcome of stimulation by native, monovalent EGF, or NRG. We demonstrate the therapeutic potential of this approach by showing that bivalent NRG (NN) can bias signaling in HER3-expressing cancer cells, resulting in some cases in decreased migration, inhibited proliferation, and increased apoptosis, whereas native NRG stimulation increased the malignant potential of the same cells. Hence, this new approach may have therapeutic relevance in ovarian, breast, lung, and other cancers in which HER3 has been implicated. [ABSTRACT FROM AUTHOR]

Abstract: The composition, presentation, and spatial orientation of extracellular matrix molecules and growth factors are key regulators of cell behavior. Here, we used self-assembling peptide nanofiber gels as a modular scaffold to investigate how fibronectin-derived adhesion ligands and different modes of epidermal growth factor (EGF) presentation synergistically regulate multiple facets of primary rat hepatocyte behavior in the context of a soft gel. In the presence of soluble EGF, inclusion of dimeric RGD and the heparin binding domain from fibronectin (HB) increased hepatocyte aggregation, spreading, and metabolic function compared to unmodified gels or gels modified with a single motif, but unlike rigid substrates, gels failed to induce DNA synthesis. Tethered EGF dramatically stimulated cell aggregation and spreading under all adhesive ligand conditions and also preserved metabolic function. Surprisingly, tethered EGF elicited DNA synthesis on gels with RGD and HB. Phenotypic differences between soluble and tethered EGF stimulation of cells on peptide gels are correlated with differences in expression and phosphorylation the EGF receptor and its heterodimerization partner ErbB2, and activation of the downstream signaling node ERK1/2. These modular matrices reveal new facets of hepatocellular biology in culture and may be more broadly useful in culture of other soft tissues. [Copyright &y& Elsevier]

Abstract: Strategies to combine aspirated marrow cells with scaffolds to treat connective tissue defects are gaining increasing clinical attention and use. In situations such as large defects where initial survival and proliferation of transplanted connective tissue progenitors (CTPs) are limiting, therapeutic outcomes might be improved by using the scaffold to deliver growth factors that promote the early stages of cell function in the graft. Signaling by the epidermal growth factor receptor (EGFR) plays a role in cell survival and has been implicated in bone development and homeostasis. Providing epidermal growth factor (EGF) in a scaffold-tethered format may sustain local delivery and shift EGFR signaling to pro-survival modes compared to soluble ligand. We therefore examined the effect of tethered EGF on osteogenic colony formation from human bone marrow aspirates in the context of three different adhesion environments using a total of 39 donors. We found that tethered EGF, but not soluble EGF, increased the numbers of colonies formed regardless of adhesion background, and that tethered EGF did not impair early stages of osteogenic differentiation. [Copyright &y& Elsevier]

Abstract: Bone graft performance can be enhanced by addition of connective tissue progenitors (CTPs) from fresh bone marrow in a manner that concentrates the CTP cell population within the graft. Here, we used small peptide adhesion ligands presented against an otherwise adhesion-resistant synthetic polymer background in order to illuminate the molecular basis for the attachment and colony formation by osteogenic CTPs from fresh human marrow, and contrast the behavior of fresh marrow to many commonly used osteogenic cell sources. The linear GRGDSPY ligand was as effective as tissue culture polystyrene in fostering attachment of culture-expanded porcine CTPs. Although this GRGDSPY peptide was more effective than control peptides in fostering alkaline phosphatase (AP)-positive colony formation from primary human marrow in 5 of the 7 patients tested, GRGDSPY was as effective as the control glass substrate in only one patient of 7. Thus, the peptide appears capable of enabling osteoblastic development from only a subpopulation of CTPs in marrow. The bone sialoprotein-derived peptide FHRRIKA was ineffective in fostering attachment of primary culture-expanded pig CTPs, although it was as effective as GRGDSPY in fostering AP-positive colonies from fresh human marrow. This study provides insights into integrin-mediated behaviors of CTPs and highlights differences between freshly isolated marrow and culture-expanded cells. [Copyright &y& Elsevier]

Epithelial organoids derived from human donor tissues are important tools in fields ranging from regenerative medicine to drug discovery. Organoid culture requires expansion of stem/progenitor cells in Matrigel, a tumor-derived extracellular matrix (ECM). An alternative completely synthetic ECM could improve reproducibility, clarify mechanistic phenomena, and enable human implantation of organoids. We designed synthetic ECMs with tunable biomolecular and biophysical properties to identify gel compositions supporting human tissue-derived stem/progenitor epithelial cells as enteroids and organoids starting with single cells rather than tissue fragments. The synthetic ECMs consist of 8-arm PEG-macromers modified with ECM-binding peptides and different combinations of integrin-binding peptides, crosslinked with peptides susceptible to matrix metalloprotease (MMP) degradation, and tuned to exhibit a range of biophysical properties. A gel containing an α2β1 integrin-binding peptide (GFOGER) and matrix binder peptides grafted to a 20 kDa 8-arm PEG macromer showed the most robust support of human duodenal and colon enteroids and endometrial organoids. In this synthetic ECM, human intestinal enteroids and endometrial organoids emerge from single cells and show cell-specific and apicobasal polarity markers upon differentiation. Intestinal enteroids, in addition, retain their proliferative capacity, are functionally responsive to basolateral stimulation, express canonical markers of intestinal crypt cells including Paneth cells, and can be serially passaged. The success of this synthetic ECM in supporting human postnatal organoid culture from multiple different donors and from both the intestine and endometrium suggests it may be broadly useful for other epithelial organoid culture. [ABSTRACT FROM AUTHOR]

In vitro tissue engineered models are poised to have significant impact on disease modeling and preclinical drug development. Reliable methods to induce microvascular networks in such microphysiological systems are needed to improve the size and physiological function of these models. By systematically engineering several physical and biomolecular properties of the cellular microenvironment (including crosslinking density, polymer density, adhesion ligand concentration, and degradability), we establish design principles that describe how synthetic matrix properties influence vascular morphogenesis in modular and tunable hydrogels based on commercial 8-arm poly (ethylene glycol) (PEG8a) macromers. We apply these design principles to generate endothelial networks that exhibit consistent morphology throughout depths of hydrogel greater than 1 mm. These PEG8a-based hydrogels have relatively high volumetric swelling ratios (>1.5), which limits their utility in confined environments such as microfluidic devices. To overcome this limitation, we mitigate swelling by incorporating a highly functional PEG-grafted alpha-helical poly (propargyl- l -glutamate) (PPLGgPEG) macromer along with the canonical 8-arm PEG8a macromer in gel formation. This hydrogel platform supports enhanced endothelial morphogenesis in neutral-swelling environments. Finally, we incorporate PEG8a-PPLGgPEG gels into microfluidic devices and demonstrate improved diffusion kinetics and microvascular network formation in situ compared to PEG8a-based gels. [ABSTRACT FROM AUTHOR]

Objective: Our aim was to characterize peritoneal cytokine profiles in patients with infertility, with and without endometriosis, to illuminate potential differences in immune profiles that may reflect mechanistic differences between these two patient populations.Design: Cross-sectional study.Setting: University hospital and research center.Patient(s): Women undergoing laparoscopy for infertility investigation (n = 107).Intervention(s): Peritoneal fluid was collected during surgery. Clinical characteristics were registered preoperatively.Main Outcome Measure(s): We determined the concentration of 48 different cytokines from the peritoneal fluid with multiplex immunoassays. Associations between cytokines and clinical findings were assessed with logistic regression and partial least squares discriminant analyses (PLS-DA).Result(s): Concentrations of SCGF-β, IL-8, HGF, and MCP-1 were significantly higher, while IL-13 was significantly lower in the endometriosis group compared with the group without endometriosis. Multiple stepwise logistic regression identified a combination of SCGF-β, IL-13, and G-CSF concentrations that predicted the presence of endometriosis with 86% sensitivity and 67% specificity. PLS-DA identified a class of 11 cytokines (SCGF-β, HGF, IL-13, MCP-1, CTACK, MCP-3, M-CSF, LIF, IL-5, IL-9, and IFN-a2) that were more characteristic of endometriosis than nonendometriosis patients.Conclusion(s): By combining univariate and multivariate analyses, profiles of cytokines more likely to be enriched or depleted in infertility patients with endometriosis compared with those without endometriosis were identified. These findings may inform future analyses of pathophysiological mechanisms of endometriosis in infertile patients, including dysregulated Th1/Th2 response and mobilization and proliferation of hematopoietic stem cells. [ABSTRACT FROM AUTHOR]

Successful delivery of DNA is a crucial first step in attaining effective gene therapy. While vectors based upon recombinant viruses have shown high transfection efficiencies, they may also pose health risks to patients and can be difficult to target to specific cell types. Non-viral (NV) vectors look to offer a safer alternative and can be engineered to more effectively treat a specific cell type or pathology, but these vectors are plagued with low transfection levels. Many barriers exist in the successful trafficking of these NV complexes to the nucleus. Current evaluations of NV gene delivery treatments in more clinical settings often focus on a single barrier at a time and may not lead to an overall improvement in gene delivery. Concurrently, more quantitative or systematic in vitro studies may not correlate well with in vivo data.Our combined approach of quantitative vector trafficking and expression assays coupled with simulation of vector specific mathematical models that describe each step of the delivery process has shown that a systems level approach can reveal the most rate- limiting steps for a given vector. These studies have shown that different vectors have different rate limiting steps and that these results can be counterintuitive when only one step is examined at a time. Established NV vectors have been compared to novel polymer carriers and adenovirus to show how synthetic carriers differ from a viral vector in in vitro culture. Ensuing model analysis has given added insight into how each vector is mechanistically different and how these carriers could be improved to obtain more effective NV therapeutics.These studies have now been extended to primary liver, coupled with device development to attain a more clinically relevant model system and more spatial resolution to study intracellular vector trafficking and localization. A scaled up and improved 3-D, perfused bioreactor has been built that allows for the long-term culture of primary hepatocytes. Within the microfabricated reactor flow channels, cells self assemble over time into tissue structures that more closely mimic hepatic morphology and phenotype than conventional 2-D cultures. This bioreactor allows for multiplexed, high-throughput assays that are not possible in animal models, and provides the micro-scale circulation and tissue structure that are lacking in traditional in vitro culture. By studying NV gene delivery in this system, quantitative experiments and experimentally-driven computational models have been developed that may better describe how a vector will perform in vivo. Gene delivery efficiency, kinetics and transgene expression in this system have been directly compared to 2-D culture systems. A newly constructed density gradient electrophoresis device can separate and collect the vesicular organelles that play an important role in gene delivery. Combined with quantitative assays for the complexed DNA plasmid or viral vector of interest, vector dynamics are tracked at cell entry, through the stages of vesicular trafficking and escape, and at nuclear import, providing data sets to generate more accurate and predictive mathematical models for vector enhancement.Molecular Therapy (2006) 13, S151–S152; doi: 10.1016/j.ymthe.2006.08.458 [ABSTRACT FROM AUTHOR]

An abstract of the article "Quantitative Analysis of Non-Viral Gene Therapy in a Three-Dimensional Liver Bioreactor," by Nathan C. Tedford, Jennifer Fang, Bonnie Huang, Karel Domansky, Linda G. Griffith and Douglas A. Lauffenburger is presented.