@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{moatti_connard_de britto_dunn_rastogi_rai_schnabel_ligler_hutson_fitzpatrick_et al._2024, title={Surgical procedure of intratympanic injection and inner ear pharmacokinetics simulation in domestic pigs}, volume={15}, ISSN={["1663-9812"]}, DOI={10.3389/fphar.2024.1348172}, abstractNote={Introduction: One major obstacle in validating drugs for the treatment or prevention of hearing loss is the limited data available on the distribution and concentration of drugs in the human inner ear. Although small animal models offer some insights into inner ear pharmacokinetics, their smaller organ size and different barrier (round window membrane) permeabilities compared to humans can complicate study interpretation. Therefore, developing a reliable large animal model for inner ear drug delivery is crucial. The inner and middle ear anatomy of domestic pigs closely resembles that of humans, making them promising candidates for studying inner ear pharmacokinetics. However, unlike humans, the anatomical orientation and tortuosity of the porcine external ear canal frustrates local drug delivery to the inner ear.Methods: In this study, we developed a surgical technique to access the tympanic membrane of pigs. To assess hearing pre- and post-surgery, auditory brainstem responses to click and pure tones were measured. Additionally, we performed 3D segmentation of the porcine inner ear images and used this data to simulate the diffusion of dexamethasone within the inner ear through fluid simulation software (FluidSim).Results: We have successfully delivered dexamethasone and dexamethasone sodium phosphate to the porcine inner ear via the intratympanic injection. The recorded auditory brainstem measurements revealed no adverse effects on hearing thresholds attributable to the surgery. We have also simulated the diffusion rates for dexamethasone and dexamethasone sodium phosphate into the porcine inner ear and confirmed the accuracy of the simulations using in-vivo data.Discussion: We have developed and characterized a method for conducting pharmacokinetic studies of the inner ear using pigs. This animal model closely mirrors the size of the human cochlea and the thickness of its barriers. The diffusion time and drug concentrations we reported align closely with the limited data available from human studies. Therefore, we have demonstrated the potential of using pigs as a large animal model for studying inner ear pharmacokinetics.}, journal={FRONTIERS IN PHARMACOLOGY}, author={Moatti, Adele and Connard, Shannon and De Britto, Novietta and Dunn, William A. and Rastogi, Srishti and Rai, Mani and Schnabel, Lauren V. and Ligler, Frances S. and Hutson, Kendall A. and Fitzpatrick, Douglas C. and et al.}, year={2024}, month={Jan} }