@article{davis_koch_watson_scull_brown_schnabel_fisher_2024, title={Controlled Stiffness of Direct-Write, Near-Field Electrospun Gelatin Fibers Generates Differences in Tenocyte Morphology and Gene Expression}, volume={146}, ISSN={0148-0731 1528-8951}, url={http://dx.doi.org/10.1115/1.4065163}, DOI={10.1115/1.4065163}, abstractNote={Abstract Tendinopathy is a leading cause of mobility issues. Currently, the cell–matrix interactions involved in the development of tendinopathy are not fully understood. In vitro tendon models provide a unique tool for addressing this knowledge gap as they permit fine control over biochemical, micromechanical, and structural aspects of the local environment to explore cell–matrix interactions. In this study, direct-write, near-field electrospinning of gelatin solution was implemented to fabricate micron-scale fibrous scaffolds that mimic native collagen fiber size and orientation. The stiffness of these fibrous scaffolds was found to be controllable between 1 MPa and 8 MPa using different crosslinking methods (EDC, DHT, DHT+EDC) or through altering the duration of crosslinking with EDC (1 h to 24 h). EDC crosslinking provided the greatest fiber stability, surviving up to 3 weeks in vitro. Differences in stiffness resulted in phenotypic changes for equine tenocytes with low stiffness fibers (∼1 MPa) promoting an elongated nuclear aspect ratio while those on high stiffness fibers (∼8 MPa) were rounded. High stiffness fibers resulted in the upregulation of matrix metalloproteinase (MMPs) and proteoglycans (possible indicators for tendinopathy) relative to low stiffness fibers. These results demonstrate the feasibility of direct-written gelatin scaffolds as tendon in vitro models and provide evidence that matrix mechanical properties may be crucial factors in cell–matrix interactions during tendinopathy formation.}, number={9}, journal={Journal of Biomechanical Engineering}, publisher={ASME International}, author={Davis, Zachary G. and Koch, Drew W. and Watson, Samantha L. and Scull, Grant M. and Brown, Ashley C. and Schnabel, Lauren V. and Fisher, Matthew B.}, year={2024}, month={Apr} }
 @article{scull_aligwekwe_rey_koch_nellenbach_sheridan_pandit_sollinger_pierce_flick_et al._2024, title={Fighting fibrin with fibrin: Vancomycin delivery into coagulase-mediated <i>Staphylococcus aureus</i> biofilms via fibrin-based nanoparticle binding}, volume={6}, ISSN={["1552-4965"]}, DOI={10.1002/jbm.a.37760}, abstractNote={Abstract Staphylococcus aureus skin and soft tissue infection is a common ailment placing a large burden upon global healthcare infrastructure. These bacteria are growing increasingly recalcitrant to frontline antimicrobial therapeutics like vancomycin due to the prevalence of variant populations such as methicillin‐resistant and vancomycin‐resistant strains, and there is currently a dearth of novel antibiotics in production. Additionally, S. aureus has the capacity to hijack the host clotting machinery to generate fibrin‐based biofilms that confer protection from host antimicrobial mechanisms and antibiotic‐based therapies, enabling immune system evasion and significantly reducing antimicrobial efficacy. Emphasis is being placed on improving the effectiveness of therapeutics that are already commercially available through various means. Fibrin‐based nanoparticles (FBNs) were developed and found to interact with S. aureus through the clumping factor A (ClfA) fibrinogen receptor and directly integrate into the biofilm matrix. FBNs loaded with antimicrobials such as vancomycin enabled a targeted and sustained release of antibiotic that increased drug contact time and reduced the therapeutic dose required for eradicating the bacteria, both in vitro and in vivo. Collectively, these findings suggest that FBN‐antibiotic delivery may be a novel and potent therapeutic tool for the treatment of S. aureus biofilm infections.}, journal={JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A}, author={Scull, Grant and Aligwekwe, Adrian and Rey, Ysabel and Koch, Drew and Nellenbach, Kimberly and Sheridan, Ana and Pandit, Sanika and Sollinger, Jennifer and Pierce, Joshua G. and Flick, Matthew J. and et al.}, year={2024}, month={Jun} }
 @article{koch_froneberger_berglund_connard_souther_v. schnabel_2024, title={IL-1β + TGF-β2 dual-licensed mesenchymal stem cells have reduced major histocompatibility class I expression and positively modulate tenocyte migration, metabolism, and gene expression}, volume={262}, ISSN={["1943-569X"]}, DOI={10.2460/javma.23.12.0708}, abstractNote={Abstract OBJECTIVE The study objectives were to 1) determine the mesenchymal stem cell (MSC) surface expression of major histocompatibility complex (MHC) class I and transcriptome-wide gene expression changes following IL-1β + TGF-β2 dual licensing and 2) evaluate if IL-1β + TGF-β2 dual-licensed MSCs had a greater ability to positively modulate tenocyte function compared to naive MSCs. SAMPLES Equine bone marrow–derived MSCs from 6 donors and equine superficial digital flexor tenocytes from 3 donors. METHODS Experiments were performed in vitro. Flow cytometry and bulk RNA sequencing were utilized to determine naive and dual-licensed MSC phenotype and transcriptome-wide changes in gene expression. Conditioned media were generated from MSCs and utilized in tenocyte cell culture assays as a method to determine the effect of MSC paracrine factors on tenocyte function. RESULTS Dual-licensed MSCs have a reduced expression of MHC class I and exhibit enrichment in functional pathways associated with the extracellular matrix, cell signaling, and tissue development. Additionally, dual-licensed MSC-conditioned media significantly improved in vitro tenocyte migration and metabolism to a greater degree than naive MSC-conditioned media. In tenocytes exposed to IL-1β, dual-licensed conditioned media also positively modulated tenocyte gene expression. CLINICAL RELEVANCE Our data indicate that conditioned media containing paracrine factors secreted from dual-licensed MSCs significantly modulates in vitro tenocyte function, which may confer benefits in vivo to healing tendons following injury. Additionally, due to reduced MHC class I expression in dual-licensed MSCs, this technique may also provide an avenue to provide an effective “off-the-shelf” allogenic source of MSCs.}, journal={JAVMA-JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION}, author={Koch, Drew W. and Froneberger, Anna and Berglund, Alix and Connard, Shannon and Souther, Alexis and V. Schnabel, Lauren}, year={2024}, month={Jun} }
 @article{connard_gaesser_clarke_linardi_even_engiles_koch_peffers_ortved_2024, title={Plasma and synovial fluid extracellular vesicles display altered microRNA profiles in horses with naturally occurring post-traumatic osteoarthritis: an exploratory study}, volume={262}, ISSN={["1943-569X"]}, DOI={10.2460/javma.24.02.0102}, abstractNote={Abstract OBJECTIVE The objective of this study was to characterize extracellular vesicles (EVs) in plasma and synovial fluid obtained from horses with and without naturally occurring post-traumatic osteoarthritis (PTOA). ANIMALS EVs were isolated from plasma and synovial fluid from horses with (n = 6) and without (n = 6) PTOA. METHODS Plasma and synovial fluid EVs were characterized with respect to quantity, size, and surface markers. Small RNA sequencing was performed, and differentially expressed microRNAs (miRNAs) underwent bioinformatic analysis to identify putative targets and to explore potential associations with specific biological processes. RESULTS Plasma and synovial fluid samples from horses with PTOA had a significantly higher proportion of exosomes and a lower proportion of microvesicles compared to horses without PTOA. Small RNA sequencing revealed several differentially expressed miRNAs, including miR-144, miR-219-3p, and miR-199a-3l in plasma and miR-199a-3p, miR-214, and miR-9094 in synovial fluid EVs. Bioinformatics analysis of the differentially expressed miRNAs highlighted their potential role in fibrosis, differentiation of chondrocytes, apoptosis, and inflammation pathways in PTOA. CLINICAL RELEVANCE We have identified dynamic molecular changes in the small noncoding signatures of plasma and synovial fluid EVs in horses with naturally occurring PTOA. These findings could serve to identify promising biomarkers in the pathogenesis of PTOA, to facilitate the development of targeted therapies, and to aid in establishing appropriate translational models of PTOA.}, journal={JAVMA-JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION}, author={Connard, Shannon S. and Gaesser, Angela M. and Clarke, Emily J. and Linardi, Renata L. and Even, Kayla M. and Engiles, Julie B. and Koch, Drew W. and Peffers, Mandy J. and Ortved, Kyla F.}, year={2024}, month={Jun}, pages={83–96} }
 @article{nellenbach_mihalko_nandi_koch_shetty_moretti_sollinger_moiseiwitsch_sheridan_pandit_et al._2024, title={Ultrasoft platelet-like particles stop bleeding in rodent and porcine models of trauma}, volume={16}, ISSN={["1946-6242"]}, DOI={10.1126/scitranslmed.adi4490}, abstractNote={Uncontrolled bleeding after trauma represents a substantial clinical problem. The current standard of care to treat bleeding after trauma is transfusion of blood products including platelets; however, donated platelets have a short shelf life, are in limited supply, and carry immunogenicity and contamination risks. Consequently, there is a critical need to develop hemostatic platelet alternatives. To this end, we developed synthetic platelet-like particles (PLPs), formulated by functionalizing highly deformable microgel particles composed of ultralow cross-linked poly ( N -isopropylacrylamide) with fibrin-binding ligands. The fibrin-binding ligand was designed to target to wound sites, and the cross-linking of fibrin polymers was designed to enhance clot formation. The ultralow cross-linking of the microgels allows the particles to undergo large shape changes that mimic platelet shape change after activation; when coupled to fibrin-binding ligands, this shape change facilitates clot retraction, which in turn can enhance clot stability and contribute to healing. Given these features, we hypothesized that synthetic PLPs could enhance clotting in trauma models and promote healing after clotting. We first assessed PLP activity in vitro and found that PLPs selectively bound fibrin and enhanced clot formation. In murine and porcine models of traumatic injury, PLPs reduced bleeding and facilitated healing of injured tissue in both prophylactic and immediate treatment settings. We determined through biodistribution experiments that PLPs were renally cleared, possibly enabled by ultrasoft particle properties. The performance of synthetic PLPs in the preclinical studies shown here supports future translational investigation of these hemostatic therapeutics in a trauma setting.}, number={742}, journal={SCIENCE TRANSLATIONAL MEDICINE}, author={Nellenbach, Kimberly and Mihalko, Emily and Nandi, Seema and Koch, Drew W. and Shetty, Jagathpala and Moretti, Leandro and Sollinger, Jennifer and Moiseiwitsch, Nina and Sheridan, Ana and Pandit, Sanika and et al.}, year={2024}, month={Apr} }
 @article{willette_gerras_sledge_koch_2023, title={A Case Report of Uterine Body Constriction Precluding Normal Parturition Leading to Dystocia in a Mare}, volume={10}, ISSN={["2306-7381"]}, DOI={10.3390/vetsci10020139}, abstractNote={A 13-year-old multiparous Quarter Horse mare was presented to the Michigan State University’s, Large Animal Emergency service for dystocia. Clinical evaluation revealed a minimally dilated cervix on vaginal examination, with a palpable deceased fetus. Postmortem evaluation following owner-elected humane euthanasia revealed a circumferential, tan, fibrous band at the base of the uterine body that constricted the uterus and was adhered to the left and right ovaries. A routine histologic section of the incarcerating cord attached to the ovary consisted predominately of dense fibrous connective tissue, large blood vessels, and a central oviduct suggestive of a rent in the broad ligament. To the authors’ knowledge, this is the first case report to describe uterine body constriction that precluded vaginal delivery of a fetus in a late gestation mare.}, number={2}, journal={VETERINARY SCIENCES}, author={Willette, Jaclyn and Gerras, Allison and Sledge, Dodd and Koch, Drew}, year={2023}, month={Feb} }
 @article{koch_schnabel_2023, title={Mesenchymal stem cell licensing: enhancing MSC function as a translational approach for the treatment of tendon injury}, volume={84}, ISSN={["1943-5681"]}, DOI={10.2460/ajvr.23.07.0154}, abstractNote={Abstract Tendon injuries are common in both veterinary and human clinical patients and result in morbidity, pain, and lost athletic performance. Consequently, utilizing naturally occurring injuries in veterinary patients as a comparative model could inform the development of novel therapies and increase translation for the treatment of human tendon injuries. Mesenchymal stem cells (MSCs) have shown considerable efficacy for the treatment of experimental and clinical superficial digital flexor tendon injury in the horse; however, the reinjury rate following treatment can remain high and MSC efficacy in treating other tendons is less well known. Additionally, the translation of MSC therapy to human tendon injury has remained poor. Recent evidence indicates that naïve MSC function can be enhanced through exogenous stimulation or manipulation of their environment. This stimulation or activation, herein termed MSC licensing, markedly alters MSC functions associated with immunomodulation, extracellular matrix remodeling, vascular development, bioactive factor production, and endogenous stromal/progenitor cell support. Additionally, a variety of licensing strategies has proven to influence MSC-secreted factors that have positively influenced outcome parameters in both in vitro and in vivo disease models separate from musculoskeletal tissues. Therefore, identifying the optimal licensing strategy for MSCs could ultimately provide an avenue for reliable and repeatable treatment of a broad range of tendon injuries of both veterinary and human clinical patients. This article details current evidence on the effects of licensed MSCs in both in vitro and in vivo disease models of different species and provides commentary on how those effector functions identified may be translated to the treatment of tendon injuries.}, number={10}, journal={AMERICAN JOURNAL OF VETERINARY RESEARCH}, author={Koch, Drew W. and Schnabel, Lauren V}, year={2023}, month={Oct} }
 @article{koch_schnabel_reynolds_berry_2023, title={Pneumatic compression therapy using the EQ Press accelerates lymphatic flow in healthy equine forelimbs as determined by lymphoscintigraphy}, volume={84}, ISSN={["1943-5681"]}, DOI={10.2460/ajvr.22.12.0214}, abstractNote={Abstract

OBJECTIVE
Limb lymphedema in horses can be debilitating and painful. Pneumatic compression therapy has shown significant benefits for people suffering from lymphedema. The objective of this study was to determine the effect of a novel, equine-specific pneumatic compression device on the lymphatic flow of healthy horse forelimbs as determined by Tc-99m sulfur colloid lymphoscintigraphy.


ANIMALS
6 healthy Thoroughbreds.


PROCEDURES
In a randomized crossover design, horses underwent bilateral forelimb lymphoscintigraphy following subcutaneous injection of Tc-99m sulfur colloid at the coronary band as untreated control or with pneumatic compression therapy using the EQ Press. Lateral, static images were obtained of the distal limb (time 0 to 60 minutes) and proximal limb (time 30 to 60 minutes) using a standard gamma camera. Lymphatic flow was determined by assigning a score to the time point at which Tc-99m sulfur colloid was first visualized at the level of the accessory carpal bone (1 to 7) in the distal limb and the cubital lymph node (1 to 4) in the proximal limb.


RESULTS
EQ Press treatment led to a significantly faster lymphatic flow of Tc-99m sulfur colloid to the predetermined anatomic locations of the accessory carpal bone (P = .002) in the distal limb and the cubital lymph node (P = .001) in the proximal limb.


CLINICAL RELEVANCE
Pneumatic compression therapy as provided by an equine-specific device encouraged lymphatic flow in healthy, nonedematous equine forelimbs. These data support further study of the EQ Press for pneumatic compression therapy in horses clinically affected by lymphedema and lymphatic drainage disorders.
}, number={4}, journal={AMERICAN JOURNAL OF VETERINARY RESEARCH}, author={Koch, Drew W. and Schnabel, Lauren V and Reynolds, Justin and Berry, Clifford R.}, year={2023}, month={Apr} }
 @article{v. schnabel_koch_2023, title={Use of mesenchymal stem cells for tendon healing in veterinary and human medicine: getting to the "core" of the problem through a one health approach}, volume={261}, ISSN={["1943-569X"]}, DOI={10.2460/javma.23.07.0388}, abstractNote={Abstract
The purpose of this manuscript, which is part of the Currents in One Health series, is to take a comparative approach to stem cell treatment for tendon injury and consider how the horse might inform treatment in other veterinary species and humans. There is increasing experimental and clinical evidence for the use of bone marrow–derived mesenchymal stem cells to treat tendon injuries in the horse. The same evidence does not currently exist for other species. This manuscript will review why the equine superficial digital flexor tendon core lesion might be considered optimal for stem cell delivery and stem cell interaction with the injury environment and will also introduce the concept of stem cell licensing for future evaluation. The companion Currents in One Health by Koch and Schnabel, AJVR, October 2023, addresses in detail what is known about stem cell licensing for the treatment of other diseases using rodent models and how this information can potentially be applied to tendon healing.}, number={10}, journal={JAVMA-JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION}, author={V. Schnabel, Lauren and Koch, Drew W.}, year={2023}, month={Oct}, pages={1435–1442} }
 @article{koch_berglund_messenger_gilbertie_ellis_schnabel_2022, title={Interleukin-1 beta in tendon injury enhances reparative gene and protein expression in mesenchymal stem cells}, volume={9}, ISSN={["2297-1769"]}, DOI={10.3389/fvets.2022.963759}, abstractNote={Tendon injury in the horse carries a high morbidity and monetary burden. Despite appropriate therapy, reinjury is estimated to occur in 50–65% of cases. Although intralesional mesenchymal stem cell (MSC) therapy has improved tissue architecture and reinjury rates, the mechanisms by which they promote repair are still being investigated. Additionally, reevaluating our application of MSCs in tendon injury is necessary given recent evidence that suggests MSCs exposed to inflammation (deemed MSC licensing) have an enhanced reparative effect. However, applying MSC therapy in this context is limited by the inadequate quantification of the temporal cytokine profile in tendon injury, which hinders our ability to administer MSCs into an environment that could potentiate their effect. Therefore, the objectives of this study were to define the temporal cytokine microenvironment in a surgically induced model of equine tendon injury using ultrafiltration probes and subsequently evaluate changes in MSC gene and protein expression following in vitro inflammatory licensing with cytokines of similar concentration as identified in vivo. In our in vivo surgically induced tendon injury model, IL-1β and IL-6 were the predominant pro-inflammatory cytokines present in tendon ultrafiltrate where a discrete peak in cytokine concentration occurred within 48 h following injury. Thereafter, MSCs were licensed in vitro with IL-1β and IL-6 at a concentration identified from the in vivo study; however, only IL-1β induced upregulation of multiple genes beneficial to tendon healing as identified by RNA-sequencing. Specifically, vascular development, ECM synthesis and remodeling, chemokine and growth factor function alteration, and immunomodulation and tissue reparative genes were significantly upregulated. A significant increase in the protein expression of IL-6, VEGF, and PGE2 was confirmed in IL-1β-licensed MSCs compared to naïve MSCs. This study improves our knowledge of the temporal tendon cytokine microenvironment following injury, which could be beneficial for the development and determining optimal timing of administration of regenerative therapies. Furthermore, these data support the need to further study the benefit of MSCs administered within the inflamed tendon microenvironment or exogenously licensed with IL-1β in vitro prior to treatment as licensed MSCs could enhance their therapeutic benefit in the healing tendon.}, journal={FRONTIERS IN VETERINARY SCIENCE}, author={Koch, Drew W. W. and Berglund, Alix K. K. and Messenger, Kristen M. M. and Gilbertie, Jessica M. M. and Ellis, Ilene M. M. and Schnabel, Lauren V. V.}, year={2022}, month={Aug} }
 @article{koch_schnabel_ellis_bates_berglund_2022, title={TGF-beta 2 enhances expression of equine bone marrow-derived mesenchymal stem cell paracrine factors with known associations to tendon healing}, volume={13}, ISSN={["1757-6512"]}, DOI={10.1186/s13287-022-03172-9}, abstractNote={Abstract
                Background
                Mesenchymal stem cells (MSCs) secrete paracrine factors and extracellular matrix proteins that contribute to their ability to support tissue healing and regeneration. Both the transcriptome and the secretome of MSCs can be altered by treating the cells with cytokines, but neither have been thoroughly investigated following treatment with the specific cytokine transforming growth factor (TGF)-β2.
              
                Methods
                RNA-sequencing and western blotting were used to compare gene and protein expression between untreated and TGF-β2-treated equine bone marrow-derived MSCs (BM-MSCs). A co-culture system was utilized to compare equine tenocyte migration during co-culture with untreated and TGF-β2-treated BM-MSCs.
              
                Results
                TGF-β2 treatment significantly upregulated gene expression of collagens, extracellular matrix molecules, and growth factors. Protein expression of collagen type I and tenascin-C was also confirmed to be upregulated in TGF-β2-treated BM-MSCs compared to untreated BM-MSCs. Both untreated and TGF-β2-treated BM-MSCs increased tenocyte migration in vitro.
              
                Conclusions
                Treating equine BM-MSCs with TGF-β2 significantly increases production of paracrine factors and extracellular matrix molecules important for tendon healing and promotes the migration of tenocytes in vitro.
              }, number={1}, journal={STEM CELL RESEARCH & THERAPY}, author={Koch, Drew W. and Schnabel, Lauren V and Ellis, Ilene M. and Bates, Rowan E. and Berglund, Alix K.}, year={2022}, month={Sep} }