Scholarly Works, Large Animal Clinical Sciences

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https://hdl.handle.net/10919/24343
Research articles, presentations, and other scholarship

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Browsing Scholarly Works, Large Animal Clinical Sciences by Department "Biomedical Sciences and Pathobiology"

Now showing 1 - 6 of 6
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    Establishing an immunocompromised porcine model of human cancer for novel therapy development with pancreatic adenocarcinoma and irreversible electroporation
    Hendricks-Wenger, Alissa; Aycock, Kenneth N.; Nagai-Singer, Margaret A.; Coutermarsh-Ott, Sheryl; Lorenzo, Melvin F.; Gannon, Jessica; Uh, Kyungjun; Farrell, Kayla; Beitel-White, Natalie; Brock, Rebecca M.; Simon, Alexander; Morrison, Holly A.; Tuohy, Joanne L.; Clark-Deener, Sherrie; Vlaisavljevich, Eli; Davalos, Rafael V.; Lee, Kiho; Allen, Irving C. (Nature Research, 2021-04-07)
    New therapies to treat pancreatic cancer are direly needed. However, efficacious interventions lack a strong preclinical model that can recapitulate patients’ anatomy and physiology. Likewise, the availability of human primary malignant tissue for ex vivo studies is limited. These are significant limitations in the biomedical device field. We have developed RAG2/IL2RG deficient pigs using CRISPR/Cas9 as a large animal model with the novel application of cancer xenograft studies of human pancreatic adenocarcinoma. In this proof-of-concept study, these pigs were successfully generated using on-demand genetic modifications in embryos, circumventing the need for breeding and husbandry. Human Panc01 cells injected subcutaneously into the ears of RAG2/IL2RG deficient pigs demonstrated 100% engraftment with growth rates similar to those typically observed in mouse models. Histopathology revealed no immune cell infiltration and tumor morphology was highly consistent with the mouse models. The electrical properties and response to irreversible electroporation of the tumor tissue were found to be similar to excised human pancreatic cancer tumors. The ample tumor tissue produced enabled improved accuracy and modeling of the electrical properties of tumor tissue. Together, this suggests that this model will be useful and capable of bridging the gap of translating therapies from the bench to clinical application.
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    Increased and prolonged human norovirus infection in RAG2/IL2RG deficient gnotobiotic pigs with severe combined immunodeficiency
    Lei, Shaohua; Ryu, Junghyun; Wen, Ke; Twitchell, Erica; Bui, Tammy; Ramesh, Ashwin; Weiss, Mariah; Li, Guohua; Samuel, Helen; Clark-Deener, Sherrie; Jiang, Xi; Lee, Kiho; Yuan, Lijuan (Nature Publishing Group, 2016-04-27)
    Application of genetically engineered (GE) large animals carrying multi-allelic modifications has been hampered by low efficiency in production and extended gestation period compared to rodents. Here, we rapidly generated RAG2/IL2RG double knockout pigs using direct injection of CRISPR/Cas9 system into developing embryos. RAG2/IL2RG deficient pigs were immunodeficient, characterized by depletion of lymphocytes and either absence of or structurally abnormal immune organs. Pigs were maintained in gnotobiotic facility and evaluated for human norovirus (HuNoV) infection. HuNoV shedding lasted for 16 days in wild type pigs, compared to 27 days (until the end of trials) in RAG2/IL2RG deficient pigs. Additionally, higher HuNoV titers were detected in intestinal tissues and contents and in blood, indicating increased and prolonged HuNoV infection in RAG2/IL2RG deficient pigs and the importance of lymphocytes in HuNoV clearance. These results suggest that GE immunodeficient gnotobiotic pigs serve as a novel model for biomedical research and will facilitate HuNoV studies.
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    Macrophage Activation in the Synovium of Healthy and Osteoarthritic Equine Joints
    Menarim, Bruno C.; Gillis, Kiersten H.; Oliver, Andrea; Ngo, Ying; Werre, Stephen R.; Barrett, Sarah H.; Rodgerson, Dwayne H.; Dahlgren, Linda A. (2020-11-26)
    Synovitis is a major component of osteoarthritis and is driven primarily by macrophages. Synovial macrophages are crucial for joint homeostasis (M2-like phenotype), but induce inflammation (M1-like) when regulatory functions become overwhelmed. Macrophage phenotypes in synovium from osteoarthritic and healthy joints are poorly characterized; however, comparative knowledge of their phenotypes during health and disease is paramount for developing targeted treatments. This study compared patterns of macrophage activation in healthy and osteoarthritic equine synovium and correlated histology with cytokine/chemokine profiles in synovial fluid. Synovial histology and immunohistochemistry for M1-like (CD86), M2-like (CD206, IL-10), and pan macrophage (CD14) markers were performed on biopsies from 29 healthy and 26 osteoarthritic equine joints. Synovial fluid cytokines (MCP-1, IL-10, PGE(2), IL-1 beta, IL-6, TNF-alpha, IL-1ra) and growth factors (GM-CSF, SDF-1 alpha+beta, IGF-1, and FGF-2) were quantified. Macrophage phenotypes were not as clearly defined in vivo as they are in vitro. All macrophage markers were expressed with minimal differences between OA and normal joints. Expression for all markers increased proportionate to synovial inflammation, especially CD86. Synovial fluid MCP-1 was higher in osteoarthritic joints while SDF-1 and IL-10 were lower, and PGE(2) concentrations did not differ between groups. Increased CD14/CD86/CD206/IL-10 expression was associated with synovial hyperplasia, consistent with macrophage recruitment and activation in response to injury. Lower synovial fluid IL-10 could suggest that homeostatic mechanisms from synovial macrophages became overwhelmed preventing inflammation resolution, resulting in chronic inflammation and OA. Further investigations into mechanisms of arthritis resolution are warranted. Developing pro-resolving therapies may provide superior results in the treatment of OA.
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    A new paraprobiotic-based treatment for control of Haemonchus contortus in sheep
    Sanders, John; Xie, Yue; Gazzola, David; Li, Hanchen; Abraham, Ambily; Flanagan, Kelly; Rus, Florentina; Miller, Melanie; Hu, Yan; Guynn, Sierra; Draper, Austin; Vakalapudi, Sridhar; Petersson, Katherine H.; Zarlenga, Dante; Li, Robert W.; Urban, Joseph F., Jr.; Ostroff, Gary R.; Zajac, Anne M.; Aroian, Raffi, V (2020-12)
    Haemonchus contortus is a critical parasite of goats and sheep. Infection by this blood-feeding gastrointestinal nematode (GIN) parasite has significant health consequences, especially in lambs and kids. The parasite has developed resistance to virtually all known classes of small molecule anthelmintics used to treat it, giving rise in some areas to multidrug resistant parasites that are very difficult to control. Thus, new anthelmintics are urgently needed. Bacillus thuringiensis (Bt) crystal protein 5B (Cry5B), a naturally occurring protein made by a bacterium widely and safely used around the world as a bioinsecticide, represents a new non-small molecule modality for treating GINs. Cry5B has demonstrated anthelmintic activities against parasites of monogastric animals, including some related to those that infect humans, but has not yet been studied in a ruminant. Here we show that H. contortus adults are susceptible to Cry5B protein in vitro. Cry5B produced in its natural form as a sporecrystal lysate against H. contortus infections in goats had no significant efficacy. However, a new Active Pharmaceutical Ingredient (API) paraprobiotic form of Cry5B called IBaCC (Inactivated Bacterium with Cytosolic Crystals), in which Cry5B crystals are encapsulated in dead Bt cell wall ghosts, showed excellent efficacy in vitro against larval stages of H. contortus and relative protein stability in bovine rumen fluid. When given to sheep experimentally infected with H. contortus as three 60 mg/kg doses, Cry5B IBaCC resulted in significant reductions in fecal egg counts (90%) and parasite burdens (72%), with a very high impact on female parasites (96% reduction). These data indicate that Cry5B IBaCC is a potent new treatment tool for small ruminants in the battle against H. contortus.
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    Polymicrobial Biofilm Interaction Between Histophilus somni and Pasteurella multocida
    Petruzzi, Briana; Dickerman, Allan W.; Lahmers, Kevin K.; Scarratt, William K.; Inzana, Thomas J. (2020-07-10)
    Histophilus somni and Pasteurella multocida are two of multiple agents responsible for bovine respiratory disease (BRD) in cattle. Following respiratory infection of calves withH. somni,P. multocidamay also be isolated from the lower respiratory tract. BecauseH. somnimay form a biofilm during BRD, we sought to determine ifP. multocidacan co-exist withH. somniin a polymicrobial biofilmin vitroandin vivo. Interactions between the two species in the biofilm were characterized and quantified by fluorescencein situhybridization (FISH). The biofilm matrix of each species was examined using fluorescently tagged lectins (FTL) specific for the exopolysaccharide (EPS) using confocal laser scanning microscopy. Bacterial interactions were determined by auto-aggregation and biofilm morphology.Pasteurella multocidaandH. somniwere evenly distributed in thein vitrobiofilm, and both species contributed to the polymicrobial biofilm matrix. The average biomass and biofilm thickness, and the total carbohydrate and protein content of the biofilm, were greatest when both species were present. Polymicrobial bacterial suspensions auto-aggregated faster than single species suspensions, suggesting physical interactions between the two species. Almost 300P. multocidagenes were significantly differentially regulated when the bacteria were in a polymicrobial biofilm compared to a mono-species biofilm, as determined by RNA-sequencing. As expected, host genes associated with inflammation and immune response were significantly upregulated at the infection site followingH. somnichallenge. EncapsulatedP. multocidaisolates not capable of forming a substantial biofilm enhanced anin vitropolymicrobial biofilm withH. somni, indicating they contributed to the polymicrobial biofilm matrix. Indirect evidence indicated that encapsulatedP. multocidaalso contributed to a polymicrobial biofilmin vivo. Only the EPS ofH. somnicould be detected by FTL staining of bovine tissues following challenge withH. somni. However, both species were isolated and an immune response to the biofilm matrix of both species was greater than the response to planktonic cells, suggesting encapsulatedP. multocidamay take advantage of theH. somnibiofilm to persist in the host during chronic BRD. These results may have important implications for the management and prevention of BRD.
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    Variation in Eimeria oocyst count and species composition in weanling beef heifers
    Lucas, A. S.; Swecker, William S.; Scaglia, G.; Lindsay, David S.; Zajac, Anne M. (American Society of Parasitology, 2006-10)
    Rectal fecal samples were collected daily on 10 consecutive days in November 2004 from I I weaned beef heifers to assess daily variation in fecal oocyst count and species composition. Subsequent samples were collected from the same animals on 15 April 2005 and 9 June 2005. Oocyst numbers were determined by the modified McMaster's test, and species were identified by examination of oocysts recovered with the Wisconsin sugar flotation technique. Soil samples were collected from the heifer pasture on 8 June 2005, and oocysts were quantified and identified to species. Mean fecal oocyst counts varied little at all sampling dates ranging from 134-377 oocysts/g. Ten Eimeria spp. were identified in fecal samples collected in November and April and 11 in June. Eimeria bovis was the most common species identified at all samplings. Mean species composition showed little variation during the 10-day sampling period in November, remained similar in April, and varied slightly in June. Twelve Eimeria spp. were identified in soil samples in proportions similar to those seen in fecal samples. The results indicate that clinically normal weanling beef heifers are likely to be infected with a diverse, but relatively stable, community of Eimeria spp.