@article{hedgespeth_snider_bitting_cruse_2023, title={The exon-skipping oligonucleotide, KitStop, depletes tissue-resident mast cells in vivo to ameliorate anaphylaxis}, volume={14}, ISSN={["1664-3224"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85148252370&partnerID=MN8TOARS}, DOI={10.3389/fimmu.2023.1006741}, abstractNote={IntroductionAnaphylaxis represents the most extreme and life-threatening form of allergic disease and is considered a medical emergency requiring immediate intervention. Additionally, some people with mastocytosis experience recurrent episodes of anaphylaxis during normal daily activities without exposure to known triggers. While acute therapy consists primarily of epinephrine and supportive care, chronic therapy relies mostly on desensitization and immunotherapy against the offending allergen, which is a time-consuming and sometimes unsuccessful process. These treatments also necessitate identification of the triggering allergen which is not always possible, and thus highlighting a need for alternative treatments for mast cell-mediated diseases.MethodsThe exon-skipping oligonucleotide KitStop was administered to mice intradermally, intraperitoneally, or systemically at a dose of 12.5 mg/kg. Local mast cell numbers were enumerated via peritoneal lavage or skin histology, and passive systemic anaphylaxis was induced to evaluate KitStop’s global systemic effect. A complete blood count and biochemistry panel were performed to assess the risk of acute toxicity following KitStop administration.ResultsHere, we report the use of an exon-skipping oligonucleotide, which we have previously termed KitStop, to safely reduce the severity and duration of the anaphylactic response via mast cell depopulation in tissues. KitStop administration results in the integration of a premature stop codon within the mRNA transcript of the KIT receptor—a receptor tyrosine kinase found primarily on mast cells and whose gain-of-function mutation can lead to systemic mastocytosis. Following either local or systemic KitStop treatment, mice had significantly reduced mast cell numbers in the skin and peritoneum. In addition, KitStop-treated mice experienced a significantly diminished anaphylactic response using a model of passive systemic anaphylaxis when compared with control mice.DiscussionKitStop treatment results in a significant reduction in systemic mast cell responses, thus offering the potential to serve as a powerful additional treatment modality for patients that suffer from anaphylaxis.}, journal={FRONTIERS IN IMMUNOLOGY}, author={Hedgespeth, Barry A. A. and Snider, Douglas B. and Bitting, Katie J. and Cruse, Glenn}, year={2023}, month={Jan} }
 @article{bitting_hedgespeth_ehrhardt-humbert_arthur_schubert_bradding_tilley_cruse_2022, title={Identification of redundancy between human Fc epsilon RI beta and MS4A6A proteins points toward additional complex mechanisms for Fc epsilon RI trafficking and signaling}, volume={12}, ISSN={["1398-9995"]}, url={https://doi.org/10.1111/all.15595}, DOI={10.1111/all.15595}, abstractNote={AbstractBackgroundAllergic diseases are triggered by signaling through the high‐affinity IgE receptor, FcεRI. In both mast cells (MCs) and basophils, FcεRI is a tetrameric receptor complex comprising a ligand‐binding α subunit (FcεRIα), a tetraspan β subunit (FcεRIβ, MS4A2) responsible for trafficking and signal amplification, and a signal transducing dimer of single transmembrane γ subunits (FcεRIγ). However, FcεRI also exists as presumed trimeric complexes that lack FcεRIβ and are expressed on several cell types outside the MC and basophil lineages. Despite known differences between humans and mice in the presence of the trimeric FcεRI complex, questions remain as to how it traffics and whether it signals in the absence of FcεRIβ. We have previously reported that targeting FcεRIβ with exon‐skipping oligonucleotides eliminates IgE‐mediated degranulation in mouse MCs, but equivalent targeting in human MCs was not effective at reducing degranulation.ResultsHere, we report that the FcεRIβ‐like protein MS4A6A exists in human MCs and compensates for FcεRIβ in FcεRI trafficking and signaling. Human MS4A6A promotes surface expression of FcεRI complexes and facilitates degranulation. MS4A6A and FcεRIβ are encoded by highly related genes within the MS4A gene family that cluster within the human gene loci 11q12‐q13, a region linked to allergy and asthma susceptibility.ConclusionsOur data suggest the presence of either FcεRIβ or MS4A6A is sufficient for degranulation, indicating that MS4A6A could be an elusive FcεRIβ‐like protein in human MCs that performs compensatory functions in allergic disease.}, number={5}, journal={ALLERGY}, author={Bitting, Katie and Hedgespeth, Barry and Ehrhardt-Humbert, Lauren C. and Arthur, Greer K. and Schubert, Alicia G. and Bradding, Peter and Tilley, Stephen L. and Cruse, Glenn}, year={2022}, month={Dec} }
 @article{hedgespeth_birkenheuer_friedenberg_olby_meurs_2021, title={A novel missense mutation of the NAT10 gene in a juvenile Schnauzer dog with chronic respiratory tract infections}, volume={35}, ISSN={["1939-1676"]}, url={https://doi.org/10.1111/jvim.16100}, DOI={10.1111/jvim.16100}, abstractNote={AbstractAn 18‐month‐old intact male Schnauzer dog was evaluated for chronic, lifelong respiratory tract infections that were unresponsive to administration of a variety of antibiotics and corticosteroids. The dog developed persistent vomiting and diarrhea around 1 year of age that was minimally responsive to diet change, antibiotics, and corticosteroids. Despite supportive care, the dog was ultimately euthanized at 20 months of age due to persistent respiratory and gastrointestinal disease. Whole genome sequencing discovered a deleterious missense A/C mutation within the NAT10 gene, a gene essential for microtubule acetylation, appropriate ciliary development, and cytokinesis. Pipeline analysis of the genomes of 579 dogs from 55 breeds did not detect this mutation. Though never described in veterinary medicine, NAT10 mutation occurs in humans with ciliary aplasia, suggesting a pathophysiological mechanism for this dog and highlighting an associated mutation or possible novel genetic cause of chronic respiratory infections in dogs.}, number={3}, journal={JOURNAL OF VETERINARY INTERNAL MEDICINE}, author={Hedgespeth, Barry A. and Birkenheuer, Adam J. and Friedenberg, Steven G. and Olby, Natasha J. and Meurs, Kathryn M.}, year={2021}, month={May}, pages={1542–1546} }
 @article{bierlein_hedgespeth_azcarate-peril_stauffer_gookin_2021, title={Dysbiosis of fecal microbiota in cats with naturally occurring and experimentally induced Tritrichomonas foetus infection}, volume={16}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0246957}, abstractNote={The protozoal pathogen Tritrichomonas foetus infects the colon of domestic cats and is a major cause of chronic colitis and diarrhea. Treatment failure is common, but antibiotics may improve clinical signs in a subset of cats, leading researchers to question involvement of the colonic microbiota in disease pathogenesis. Studies performed in women with venereal Trichomonas vaginalis infections have revealed that dysbiosis of host microbiota contributes to pathogenicity with similar findings also found in mice with intestinal Tritrichomonas musculis The aim of this study was to characterize differences in the fecal microbiota of cats with and without naturally occurring T. foetus infection and in a group of kittens prior to and after experimentally induced infection. Archived fecal DNA from cats undergoing testing for T. foetus infection (n = 89) and experimentally infected kittens (n = 4; at pre-, 2 weeks, and 9 weeks post-infection) were analyzed by sequencing of 16S rRNA genes. Amongst the naturally infected population, the genera Megamonas and Helicobacter were significantly increased in prevalence and abundance in cats testing positive for T. foetus infection. In the group of four experimentally infected kittens, fecal samples post-infection had significantly lower abundance of genus Dialister and Megamonas and greater abundance of the class Betaproteobacteria and family Succinivibrionaceae. We hypothesize that T. foetus promotes dysbiosis by competition for fermentable substrates used by these bacteria and that metabolic byproducts may contribute to the pathogenesis of colonic inflammation and diarrhea. Future studies are warranted for the measurement of fecal concentrations of microbial and protozoal metabolites in cats with T. foetus infection for the identification of potential therapeutic targets.}, number={2}, journal={PLOS ONE}, author={Bierlein, Metzere and Hedgespeth, Barry A. and Azcarate-Peril, M. Andrea and Stauffer, Stephen H. and Gookin, Jody L.}, year={2021}, month={Feb} }
 @article{kong_bennett_jania_chason_german_adouli_budney_oby_heusden_lazarowski_et al._2021, title={Identification of an ATP/P2X7/mast cell pathway mediating ozone-induced bronchial hyperresponsiveness}, volume={6}, ISSN={["2379-3708"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85118886921&partnerID=MN8TOARS}, DOI={10.1172/jci.insight.140207}, abstractNote={Ozone is a highly reactive environmental pollutant with well-recognized adverse effects on lung health. Bronchial hyperresponsiveness (BHR) is one consequence of ozone exposure, particularly for individuals with underlying lung disease. Our data demonstrated that ozone induced substantial ATP release from human airway epithelia in vitro and into the airways of mice in vivo and that ATP served as a potent inducer of mast cell degranulation and BHR, acting through P2X7 receptors on mast cells. Both mast cell–deficient and P2X7 receptor–deficient (P2X7–/–) mice demonstrated markedly attenuated BHR to ozone. Reconstitution of mast cell–deficient mice with WT mast cells and P2X7–/– mast cells restored ozone-induced BHR. Despite equal numbers of mast cells in reconstituted mouse lungs, mice reconstituted with P2X7–/– mast cells demonstrated significantly less robust BHR than mice reconstituted with WT mast cells. These results support a model where P2X7 on mast cells and other cell types contribute to ozone-induced BHR.}, number={21}, journal={JCI INSIGHT}, author={Kong, Xiaomei and Bennett, William C. and Jania, Corey M. and Chason, Kelly D. and German, Zachary and Adouli, Jennifer and Budney, Samuel D. and Oby, Brandon T. and Heusden, Catharina and Lazarowski, Eduardo R. and et al.}, year={2021}, month={Nov} }
 @article{hedgespeth_stauffer_robertson_gookin_2020, title={Association of fecal sample collection technique and treatment history with Tritrichomonas foetus polymerase chain reaction test results in 1717 cats}, volume={34}, ISSN={["1939-1676"]}, url={http://dx.doi.org/10.1111/jvim.15727}, DOI={10.1111/jvim.15727}, abstractNote={AbstractBackgroundFecal polymerase chain reaction (PCR) testing for Tritrichomonas foetus is considered the most sensitive means for diagnosis of infection but results could be influenced by fecal collection technique and prior use of antimicrobial drugs.ObjectivesTo establish any association between fecal collection technique or treatment history and results of fecal PCR testing for T. foetus.AnimalsFecal samples from 1717 cats submitted by veterinarians between January 2012 and December 2017.MethodsThis study used a retrospective analysis. T. foetus PCR test results from 1808 fecal samples submitted for diagnostic testing were examined for their association with method of fecal collection and prior antimicrobial treatments. Data were collected from sample submission form.ResultsPositive T. foetus PCR test results were obtained for 274 (16%) cats. Fecal samples collected via fecal loop had increased probability of positive PCR test results (odds ratio [OR] 2.04, 95% confidence interval [CI] 1.31‐3.17, P = .002) compared to samples collected by colonic flush. There was no association between PCR test results and treatment history, treatment type, or prior treatment with ronidazole. After an initial positive PCR test, 4/19 (21%; 95% CI 2.7%‐39.4%) cats treated with ronidazole had a second positive test result.Conclusions and Clinical ImportanceResults of this study support that fecal samples collected by loop might be better for PCR diagnosis of T. foetus infection. Lack of association of ronidazole with PCR test results and a 21% all‐potential‐causes failure rate of ronidazole in cats with preconfirmed infection are important limitations to use of this drug.}, number={2}, journal={JOURNAL OF VETERINARY INTERNAL MEDICINE}, author={Hedgespeth, Barry A. and Stauffer, Stephen H. and Robertson, James B. and Gookin, Jody L.}, year={2020}, month={Mar}, pages={734–741} }