Browsing by Author "Coutermarsh-Ott, Sheryl"

Now showing 1 - 20 of 33
  • Thumbnail Image
    Ablative and Immunostimulatory Effects of Histotripsy Ablation in a Murine Osteosarcoma Model
    Hay, Alayna N.; Imran, Khan Mohammad; Hendricks-Wenger, Alissa; Gannon, Jessica M.; Sereno, Jacqueline; Simon, Alex; Lopez, Victor A.; Coutermarsh-Ott, Sheryl; Vlaisavljevich, Eli; Allen, Irving C.; Tuohy, Joanne L. (MDPI, 2023-10-09)
    Background: Osteosarcoma (OS) is the most frequently occurring malignant bone tumor in humans, primarily affecting children and adolescents. Significant advancements in treatment options for OS have not occurred in the last several decades, and the prognosis remains grim with only a 70% rate of 5-year survival. The objective of this study was to investigate the focused ultrasound technique of histotripsy as a novel, noninvasive treatment option for OS. Methods: We utilized a heterotopic OS murine model to establish the feasibility of ablating OS tumors with histotripsy in a preclinical setting. We investigated the local immune response within the tumor microenvironment (TME) via immune cell phenotyping and gene expression analysis. Findings: We established the feasibility of ablating heterotopic OS tumors with ablation characterized microscopically by loss of cellular architecture in targeted regions of tumors. We observed greater populations of macrophages and dendritic cells within treated tumors and the upregulation of immune activating genes 72 h after histotripsy ablation. Interpretation: This study was the first to investigate histotripsy ablation for OS in a preclinical murine model, with results suggesting local immunomodulation within the TME. Our results support the continued investigation of histotripsy as a novel noninvasive treatment option for OS patients to improve clinical outcomes and patient prognosis.
  • Thumbnail Image
    ASC-Mediated Inflammation and Pyroptosis Attenuates Brucella abortus Pathogenesis Following the Recognition of gDNA
    Tupik, Juselyn D.; Coutermarsh-Ott, Sheryl; Benton, Angela H.; King, Kellie A.; Kiryluk, Hanna D.; Caswell, Clayton C.; Allen, Irving C. (MDPI, 2020-11-30)
    Brucella abortus is a zoonotic pathogen that causes brucellosis. Because of Brucella’s unique LPS layer and intracellular localization predominately within macrophages, it can often evade immune detection. However, pattern recognition receptors are capable of sensing Brucella pathogen-associated molecular patterns (PAMPS). For example, NOD-like receptors (NLRs) can form a multi-protein inflammasome complex to attenuate Brucella pathogenesis. The inflammasome activates IL-1β and IL-18 to drive immune cell recruitment. Alternatively, inflammasome activation also initiates inflammatory cell death, termed pyroptosis, which augments bacteria clearance. In this report, we assess canonical and non-canonical inflammasome activation following B. abortus infection. We conducted in vivo studies using Asc−/− mice and observed decreased mouse survival, immune cell recruitment, and increased bacteria load. We also conducted studies with Caspase-11−/− mice and did not observe any significant impact on B. abortus pathogenesis. Through mechanistic studies using Asc−/− macrophages, our data suggests that the protective role of ASC may result from the induction of pyroptosis through a gasdermin D-dependent mechanism in macrophages. Additionally, we show that the recognition of Brucella is facilitated by sensing the PAMP gDNA rather than the less immunogenic LPS. Together, these results refine our understanding of the role that inflammasome activation and pyroptosis plays during brucellosis.
  • Thumbnail Image
    Battling Bacteria: Characterizing the NOD-Like Receptor (NLR) Immune Response to Brucella abortus and Borrelia burgdorferi in Host-pathogen Interactions
    Tupik, Juselyn D. (Virginia Tech, 2024-08-19)
    The innate immune system is integral for defense against infectious diseases. Characterized by Pattern Recognition Receptors (PRRs), which sense conserved molecular motifs known as Pathogen-Associated Molecular Patterns (PAMPs), the innate immune system sets a system of checks and balances to regulate inflammation in host defense. In this dissertation, we focus on one class of PRRs known as the NOD-like Receptors (NLRs) in response to bacterial diseases. This class consists of pro-inflammatory receptors that form a multi-protein complex termed the inflammasome, as well as regulatory NLRs that modulate inflammation. Here, we investigated the roles of inflammasomes and negative regulatory NLRX1 in response to bacterial diseases. First, we studied brucellosis, a zoonotic, chronic disease often transmitted in unpasteurized dairy products from livestock. Using murine models and bone marrow-derived macrophages (BMDMs) challenged with Brucella abortus, we found that canonical inflammasomes in murine models were protective against brucellosis through the initiation of inflammatory cell death called pyroptosis. In contrast, the inhibition of inflammation by NLRX1 adversely led to increased pathology in the spleen and liver in infected murine models. Despite these contrasting results, Brucella genomic DNA was an effective PAMP for NLR recognition. These results suggest the importance of DNA recognition by NLRs during brucellosis. Second, we investigated NLRX1 regulation of Borrelia burgdorferi in Lyme arthritis using murine models. Characterized by persistent inflammation of the joints, Lyme arthritis is an enigmatic and difficult inflammatory condition to resolve. We found that NLRX1 was protective against arthritis. By characterizing changes in gene and protein expression of infected ankle joints, in addition to in vitro studies in BMDMs and fibroblasts, we found that NLRX1 enhances cell migration and regulates cell metabolism. Our results suggest that NLRX1 may metabolically shift macrophages toward a more favorable wound-healing environment for arthritis resolution. Ultimately, this work emphasizes the importance of balance in NLR signaling, which occurs within NLRs and from crosstalk with other inflammatory pathways. Further, NLR signaling is highly multifaceted and context-specific for the cell type and bacterial disease, showcasing the complexity of host-pathogen interactions when battling bacteria.
  • Thumbnail Image
    Caspase-11 Modulates Inflammation and Attenuates Toxoplasma gondii Pathogenesis
    Coutermarsh-Ott, Sheryl; Doran, John T.; Campbell, Caroline; Williams, Tere M.; Lindsay, David S.; Allen, Irving C. (Hindawi, 2016-06-09)
    Toxoplasma gondii is an obligate intracellular parasite that is the etiologic agent responsible for toxoplasmosis. Infection with T. gondii results in activation of nucleotide binding domain and leucine rich repeat containing receptors (NLRs). NLR activation leads to inflammasome formation, the activation of caspase-1, and the subsequent cleavage of IL-1β and IL-18. Recently, a noncanonical inflammasome has been characterized which functions through caspase-11 and appears to augment many biological functions previously considered to be dependent upon the canonical inflammasome. To better elucidate the function of this noncanonical inflammasome in toxoplasmosis, we utilized Asc−/− and Casp11−/− mice and infected these animals with T. gondii. Our data indicates that caspase-11 modulates the innate immune response to T. gondii through a mechanism which is distinct from that currently described for the canonical inflammasome. Asc−/− mice demonstrated increased disease pathogenesis during the acute phase of T. gondii infection, whereas Casp11−/− mice demonstrated significantly attenuated disease pathogenesis and reduced inflammation. This attenuated host response was associated with reduced local and systemic cytokine production, including diminished IL-1β. During the chronic phase of infection, caspase-11 deficiency resulted in increased neuroinflammation and tissue cyst burden in the brain. Together, our data suggest that caspase-11 functions to protect the host by enhancing inflammation during the early phase of infection in an effort to minimize disease pathogenesis during later stages of toxoplasmosis.
  • Thumbnail Image
    Characterizing the Ablative Effects of Histotripsy for Osteosarcoma: In Vivo Study in Dogs
    Ruger, Lauren N.; Hay, Alayna N.; Vickers, Elliana R.; Coutermarsh-Ott, Sheryl; Gannon, Jessica M.; Covell, Hannah S.; Daniel, Gregory B.; Laeseke, Paul F.; Ziemlewicz, Timothy J.; Kierski, Katharine R.; Ciepluch, Brittany J.; Vlaisavljevich, Eli; Tuohy, Joanne L. (MDPI, 2023-01-25)
    Osteosarcoma (OS) is a malignant bone tumor treated by limb amputation or limb salvage surgeries and chemotherapy. Histotripsy is a non-thermal, non-invasive focused ultrasound therapy using controlled acoustic cavitation to mechanically disintegrate tissue. Recent ex vivo and in vivo pilot studies have demonstrated the ability of histotripsy for ablating OS but were limited in scope. This study expands on these initial findings to more fully characterize the effects of histotripsy for bone tumors, particularly in tumors with different compositions. A prototype 500 kHz histotripsy system was used to treat ten dogs with suspected OS at an intermediate treatment dose of 1000 pulses per location. One day after histotripsy, treated tumors were resected via limb amputation, and radiologic and histopathologic analyses were conducted to determine the effects of histotripsy for each patient. The results of this study demonstrated that histotripsy ablation is safe and feasible in canine patients with spontaneous OS, while offering new insights into the characteristics of the achieved ablation zone. More extensive tissue destruction was observed after histotripsy compared to that in previous reports, and radiographic changes in tumor size and contrast uptake following histotripsy were reported for the first time. Overall, this study significantly expands our understanding of histotripsy bone tumor ablation and informs future studies for this application.
  • Thumbnail Image
    Clinical outcomes in dogs with localized splenic histiocytic sarcoma treated with splenectomy with or without adjuvant chemotherapy
    Latifi, Max; Tuohy, Joanne L.; Coutermarsh-Ott, Sheryl; Klahn, Shawna L.; Leeper, Haley; Dervisis, Nikolaos G. (Wiley, 2020-09-28)
    Background: Localized splenic histiocytic sarcoma (HS) in dogs is a poorly understood disease, and could have longer survival times than disseminated or hemophagocytic HS. Understanding the clinical behavior of localized splenic HS can refine treatment recommendations. Objective: To describe the clinical characteristics and outcomes of dogs with localized splenic HS. Animals: Fourteen client-owned dogs with histologically confirmed splenic HS that received splenectomy. Methods: Multi-institutional retrospective case series—medical records of dogs with splenic HS were reviewed. Dog signalment, clinicopathologic data, primary and adjuvant treatments, and outcomes were obtained. Survival data were calculated using Kaplan-Meier analysis. Dog variables such as age, weight, platelet counts were reported using descriptive statistics. The Cox proportional hazards regression method was used to determine whether potential risk factors (weight, age, albumin level, hematocrit, and platelet count) were associated with PFI. Results: Median survival time for the dogs in this study was 427 days. Twelve dogs received adjuvant lomustine-based chemotherapy. Five dogs (35.7%) were suspected or confirmed to have developed metastatic disease. Eleven dogs died of disease, 1 dog died of unrelated cause, and 2 dogs were alive at final follow-up. Conclusions and Clinical Significance: Histiocytic sarcoma in dogs can manifest as a localized form in the spleen. Dogs with localized splenic HS treated with surgery ± chemotherapy can experience survival times over a year.
  • Thumbnail Image
    Differential pathogenesis of Usutu virus isolates in mice
    Kuchinsky, Sarah C.; Hawks, Seth A.; Mossel, Eric C.; Coutermarsh-Ott, Sheryl; Duggal, Nisha K. (PLOS, 2020-10-12)
    Usutu virus (USUV; Flavivirus), a close phylogenetic and ecological relative of West Nile virus, is a zoonotic virus that can cause neuroinvasive disease in humans. USUV is maintained in an enzootic cycle between Culex mosquitoes and birds. Since the first isolation in 1959 in South Africa, USUV has spread throughout Africa and Europe. Reported human cases have increased over the last few decades, primarily in Europe, with symptoms ranging from mild febrile illness to severe neurological effects. In this study, we investigated whether USUV has become more pathogenic during emergence in Europe. Interferon α/β receptor knockout (Ifnar1-/-) mice were inoculated with recent USUV isolates from Africa and Europe, as well as the historic 1959 South African strain. The three tested African strains and one European strain from Spain caused 100% mortality in inoculated mice, with similar survival times and histopathology in tissues. Unexpectedly, a European strain from the Netherlands caused only 12% mortality and significantly less histopathology in tissues from mice compared to mice inoculated with the other strains. Viremia was highest in mice inoculated with the recent African strains and lowest in mice inoculated with the Netherlands strain. Based on phylogenetics, the USUV isolates from Spain and the Netherlands were derived from separate introductions into Europe, suggesting that disease outcomes may differ for USUV strains circulating in Europe. These results also suggest that while more human USUV disease cases have been reported in Europe recently, circulating African USUV strains are still a potential major health concern.
  • Thumbnail Image
    Effect of Salmonella enterica serovar Typhimurium VNP20009 and VNP20009 with restored chemotaxis on 4T1 mouse mammary carcinoma progression
    Coutermarsh-Ott, Sheryl; Broadway, Katherine M.; Scharf, Birgit E.; Allen, Irving C. (Impact Journals, 2017-05-16)
    A variety of bacterial strains have been evaluated as bio-therapeutic and immunomodulatory agents to treat cancer. One such strain, Salmonella enterica serovar Typhimurium VNP20009, which is attenuated by a purine auxotrophic mutation and modified lipid A, is characterized in previous models as a safely administered, tumor colonizing agent. However, earlier work tended to use less aggressive cancer cell lines and immunocompromised animal models. Here, we investigated the safety and efficacy of VNP20009 in a highly malignant murine model of human breast cancer. Additionally, as VNP20009 has recently been found to have a defective chemotaxis system, we tested whether restoring chemotaxis would improve anti-cancer properties in this model system. Exposure to VNP20009 had no significant effect on primary mammary tumor size or pulmonary metastasis, and the tumor colonizing process appeared chemotaxis independent. Moreover, tumor-bearing mice exposed to Salmonella exhibited increased morbidity that was associated with significant liver disease. Our results suggest that VNP20009 may not be safe or efficacious when used in aggressive, metastatic breast cancer models utilizing immunocompetent animals.
  • Thumbnail Image
    Enemy of My Enemy: A Novel Insect-Specific Flavivirus Offers a Promising Platform for a Zika Virus Vaccine
    Porier, Danielle L.; Wilson, Sarah N.; Auguste, Dawn I.; Leber, Andrew; Coutermarsh-Ott, Sheryl; Allen, Irving C.; Caswell, Clayton C.; Budnick, James A.; Bassaganya-Riera, Josep; Hontecillas, Raquel; Weger-Lucarelli, James; Weaver, Scott C.; Auguste, A. Jonathan (MDPI, 2021-10-07)
    Vaccination remains critical for viral disease outbreak prevention and control, but conventional vaccine development typically involves trade-offs between safety and immunogenicity. We used a recently discovered insect-specific flavivirus as a vector in order to develop an exceptionally safe, flavivirus vaccine candidate with single-dose efficacy. To evaluate the safety and efficacy of this platform, we created a chimeric Zika virus (ZIKV) vaccine candidate, designated Aripo/Zika virus (ARPV/ZIKV). ZIKV has caused immense economic and public health impacts throughout the Americas and remains a significant public health threat. ARPV/ZIKV vaccination showed exceptional safety due to ARPV/ZIKV’s inherent vertebrate host-restriction. ARPV/ZIKV showed no evidence of replication or translation in vitro and showed no hematological, histological or pathogenic effects in vivo. A single-dose immunization with ARPV/ZIKV induced rapid and robust neutralizing antibody and cellular responses, which offered complete protection against ZIKV-induced morbidity, mortality and in utero transmission in immune-competent and -compromised murine models. Splenocytes derived from vaccinated mice demonstrated significant CD4+ and CD8+ responses and significant cytokine production post-antigen exposure. Altogether, our results further support that chimeric insect-specific flaviviruses are a promising strategy to restrict flavivirus emergence via vaccine development.
  • Thumbnail Image
    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.
  • Thumbnail Image
    High intensity focused ultrasound for the treatment of solid tumors: a pilot study in canine cancer patients
    Carroll, Jennifer; Coutermarsh-Ott, Sheryl; Klahn, Shawna L.; Tuohy, Joanne L.; Barry, Sabrina L.; Allen, Irving C.; Hay, Alayna N.; Ruth, Jeffrey; Dervisis, Nikolaos G. (Taylor & Francis, 2022-01)
    Purpose: To investigate the safety, feasibility, and outcomes of High-Intensity Focused Ultrasound (HIFU) for the treatment of solid tumors in a spontaneous canine cancer model. Methods: Dogs diagnosed with subcutaneous solid tumors were recruited, staged and pretreatment biopsies were obtained. A single HIFU treatment was delivered to result in partial tumor ablation using a commercially available HIFU unit. Tumors were resected 3-6 days post HIFU and samples obtained for histopathology and immunohistochemistry. Total RNA was isolated from paired pre and post treated FFPE tumor samples, and quantitative gene expression analysis was performed using the nCounter Canine IO Panel. Results: A total of 20 dogs diagnosed with solid tumors were recruited and treated in the study. Tumors treated included Soft Tissue Sarcoma (n = 15), Mast Cell Tumor (n = 3), Osteosarcoma (n = 1), and Thyroid Carcinoma (n = 1). HIFU was well tolerated with only 1 dog experiencing a clinically significant adverse event. Pathology confirmed the presence of complete tissue ablation at the HIFU targeted site and immunohistochemistry indicated immune cell infiltration at the treated/untreated tumor border. Quantitative gene expression analysis indicated that 28 genes associated with T-cell activation were differentially expressed post-HIFU. Conclusions: HIFU appears to be safe and feasible for the treatment of subcutaneous canine solid tumors, resulting in ablation of the targeted tissue. HIFU induced immunostimulatory changes, highlighting the canine cancer patient as an attractive model for studying the effects of focal ablation therapies on the tumor microenvironment.
  • Thumbnail Image
    High-Frequency Irreversible Electroporation for Treatment of Primary Liver Cancer: A Proof-of-Principle Study in Canine Hepatocellular Carcinoma
    Partridge, Brittanie R.; O'Brien, Timothy J.; Lorenzo, Melvin F.; Coutermarsh-Ott, Sheryl; Barry, Sabrina L.; Stadler, Krystina L.; Muro, Noelle; Meyerhoeffer, Mitchell; Allen, Irving C.; Davalos, Rafael V.; Dervisis, Nikolaos G. (2020-03)
    Purpose: To determine the safety and feasibility of percutaneous high-frequency irreversible electroporation (HFIRE) for primary liver cancer and evaluate the HFIRE-induced local immune response. Materials and Methods: HFIRE therapy was delivered percutaneously in 3 canine patients with resectable hepatocellular carcinoma (HCC) in the absence of intraoperative paralytic agents or cardiac synchronization. Pre- and post-HFIRE biopsy samples were processed with histopathology and immunohistochemistry for CD3, CD4, CD8, and CD79a. Blood was collected on days 0, 2, and 4 for complete blood count and chemistry. Numeric models were developed to determine the treatment-specific lethal thresholds for malignant canine liver tissue and healthy porcine liver tissue. Results: HFIRE resulted in predictable ablation volumes as assessed by posttreatment CT. No detectable cardiac interference and minimal muscle contraction occurred during HFIRE. No clinically significant adverse events occurred secondary to HFIRE. Microscopically, a well-defined ablation zone surrounded by a reactive zone was evident in the majority of samples. This zone was composed primarily of maturing collagen interspersed with CD3(+)/CD4(-)/CD8(-) lymphocytes in a proinflammatory microenvironment. The average ablation volumes for the canine HCC patients and the healthy porcine tissue were 3.89 cm(3) +/- 0.74 and 1.56 cm(3) +/- 0.16, respectively (P = .03), and the respective average lethal thresholds were 710 V/cm +/- 28.2 and 957 V/cm +/- 24.4 V/cm (P = .0004). Conclusions: HFIRE can safely and effectively be delivered percutaneously, results in a predictable ablation volume, and is associated with lymphocytic tumor infiltration. This is the first step toward the use of HFIRE for treatment of unresectable liver tumors.
  • Thumbnail Image
    High-frequency irreversible electroporation is an effective tumor ablation strategy that induces immunologic cell death and promotes systemic anti-tumor immunity
    Ringel-Scaia, Veronica M.; Beitel-White, Natalie; Lorenzo, Melvin F.; Brock, Rebecca M.; Huie, Kathleen E.; Coutermarsh-Ott, Sheryl; Eden, Kristin; McDaniel, Dylan K.; Verbridge, Scott S.; Rossmeisl, John H. Jr.; Oestreich, Kenneth J.; Davalos, Rafael V.; Allen, Irving C. (2019-06)
    Background: Despite promising treatments for breast cancer, mortality rates remain high and treatments for metastatic disease are limited. High-frequency irreversible electroporation (H-FIRE) is a novel tumor ablation technique that utilizes high-frequency bipolar electric pulses to destabilize cancer cell membranes and induce cell death. However, there is currently a paucity of data pertaining to immune system activation following H-FIRE and other electroporation based tumor ablation techniques. Methods: Here, we utilized the mouse 4T1 mammary tumor model to evaluate H-FIRE treatment parameters on cancer progression and immune system activation in vitro and in vivo. Findings: H-FIRE effectively ablates the primary tumor and induces a pro-inflammatory shift in the tumor microenvironment. We further show that local treatment with H-FIRE significantly reduces 4T1 metastases. H-FIRE kills 4T1 cells through non-thermal mechanisms associated with necrosis and pyroptosis resulting in damage associated molecular pattern signaling in vitro and in vivo. Our data indicate that the level of tumor ablation correlates with increased activation of cellular immunity. Likewise, we show that the decrease in metastatic lesions is dependent on the intact immune system and H-FIRE generates 4T1 neoantigens that engage the adaptive immune system to significantly attenuate tumor progression. Interpretation: Cell death and tumor ablation following H-FIRE treatment activates the local innate immune system, which shifts the tumor microenvironment from an anti-inflammatory state to a pro-inflammatory state. The non-thermal damage to the cancer cells and increased innate immune system stimulation improves antigen presentation, resulting in the engagement of the adaptive immune system and improved systemic anti-tumor immunity. (C) 2019 The Authors. Published by Elsevier B.V.
  • Thumbnail Image
    Histotripsy ablation for the treatment of feline injection site sarcomas: a first-in-cat in vivo feasibility study
    Ruger, Lauren N.; Yang, Ester; Coutermarsh-Ott, Sheryl; Vickers, Elliana; Gannon, Jessica; Nightengale, Marlie; Hsueh, Andy; Ciepluch, Brittany; Dervisis, Nikolaos; Vlaisavljevich, Eli; Klahn, Shawna (Taylor & Francis, 2023)
    Purpose Feline soft tissue sarcoma (STS) and injection site sarcoma (fISS) are rapidly growing tumors with low metastatic potential, but locally aggressive behavior. Histotripsy is a non-invasive focused ultrasound therapy using controlled acoustic cavitation to mechanically disintegrate tissue. In this study, we investigated the in vivo safety and feasibility of histotripsy to treat fISS using a custom 1 MHz transducer. Materials and Methods Three cats with naturally-occurring STS were treated with histotripsy before surgical removal of the tumor 3 to 6 days later. Gross and histological analyses were used to characterize the ablation efficacy of the treatment, and routine immunohistochemistry and batched cytokine analysis were used to investigate the acute immunological effects of histotripsy. Results Results showed that histotripsy ablation was achievable and well-tolerated in all three cats. Precise cavitation bubble clouds were generated in all patients, and hematoxylin & eosin stained tissues revealed ablative damage in targeted regions. Immunohistochemical results identified an increase in IBA-1 positive cells in treated tissues, and no significant changes in cytokine concentrations were identified post-treatment. Conclusions Overall, the results of this study demonstrate the safety and feasibility of histotripsy to target and ablate superficial feline STS and fISS tumors and guide the clinical development of histotripsy devices for this application.
  • Thumbnail Image
    Histotripsy Ablation in Preclinical Animal Models of Cancer and Spontaneous Tumors in Veterinary Patients: A Review
    Hendricks-Wenger, Alissa; Arnold, Lauren; Gannon, Jessica; Simon, Alex; Singh, Neha; Sheppard, Hannah; Nagai-Singer, Margaret A.; Imran, Khan Mohammed; Lee, Kiho; Clark-Deener, Sherrie; Byron, Christopher R.; Edwards, Michael R.; Larson, Martha M.; Rossmeisl, John H. Jr.; Coutermarsh-Ott, Sheryl; Eden, Kristin; Dervisis, Nikolaos G.; Klahn, Shawna L.; Tuohy, Joanne L.; Allen, Irving C.; Vlaisavljevich, Eli (IEEE, 2021-09-03)
    New therapeutic strategies are direly needed in the fight against cancer. Over the last decade, several tumor ablation strategies have emerged as stand-alone or combination therapies. Histotripsy is the first completely noninvasive, nonthermal, and nonionizing tumor ablation method. Histotripsy can produce consistent and rapid ablations, even near critical structures. Additional benefits include real-time image guidance, high precision, and the ability to treat tumors of any predetermined size and shape. Unfortunately, the lack of clinically and physiologically relevant preclinical cancer models is often a significant limitation with all focal tumor ablation strategies. The majority of studies testing histotripsy for cancer treatment have focused on small animal models, which have been critical in moving this field forward and will continue to be essential for providing mechanistic insight. While these small animal models have notable translational value, there are significant limitations in terms of scale and anatomical relevance. To address these limitations, a diverse range of large animal models and spontaneous tumor studies in veterinary patients have emerged to complement existing rodent models. These models and veterinary patients are excellent at providing realistic avenues for developing and testing histotripsy devices and techniques designed for future use in human patients. Here, we provide a review of animal models used in preclinical histotripsy studies and compare histotripsy ablation in these models using a series of original case reports across a broad spectrum of preclinical animal models and spontaneous tumors in veterinary patients.
  • Thumbnail Image
    Histotripsy Ablation of Bone Tumors: Feasibility Study in Excised Canine Osteosarcoma Tumors
    Arnold, Lauren; Hendricks-Wenger, Alissa; Coutermarsh-Ott, Sheryl; Gannon, Jessica; Hay, Alayna N.; Dervisis, Nikolaos G.; Klahn, Shawna L.; Allen, Irving C.; Tuohy, Joanne L.; Vlaisavljevich, Eli (Elsevier, 2021-12)
    Osteosarcoma (OS) is a primary bone tumor affecting both dogs and humans. Histotripsy is a non-thermal, non-invasive focused ultrasound method using controlled acoustic cavitation to mechanically disintegrate tissue. In this study, we investigated the feasibility of treating primary OS tumors with histotripsy using a 500-kHz transducer on excised canine OS samples harvested after surgery at the Veterinary Teaching Hospital at Virginia Tech. Samples were embedded in gelatin tissue phantoms and treated with the 500-kHz histotripsy system using one- or two-cycle pulses at a pulse repetition frequency of 250 Hz and a dosage of 4000 pulses/point. Separate experiments also assessed histotripsy effects on normal canine bone and nerve using the same pulsing parameters. After treatment, histopathological evaluation of the samples was completed. To determine the feasibility of treating OS through intact skin/soft tissue, additional histotripsy experiments assessed OS with overlying tissues. Generation of bubble clouds was achieved at the focus in all tumor samples at peak negative pressures of 26.2 ± 4.5 MPa. Histopathology revealed effective cell ablation in treated areas for OS tumors, with no evidence of cell death or tissue damage in normal tissues. Treatment through tissue/skin resulted in generation of well-confined bubble clouds and ablation zones inside OS tumors. Results illustrate the feasibility of treating OS tumors with histotripsy. CORRIGENDUM: The authors regret that errors were present in the above article. The legend for Figure 5 on page 3441 should read “Fig. 5. Normal, healthy, non-neoplastic bone was excised from amputated canine limbs and subjected to histology. No histological differences were noted between untreated (a: magnification 4 x, b: magnification 40 x) and treated samples (c: magnification 4 x, d: magnification 40 x).” Also, the final section heading on page 3439 should read “Histotripsy ablation of ex vivo bone and nerve specimens.” Finally, the reference after the last complete sentence on page 3437 is incomplete and should read “Focal pressure waveforms for the 500-kHz transducer were measured using a custom-built fiberoptic hydrophone (FOPH) in degassed water at the focal point of each transducer (Parsons et al. 2006).” The authors would like to apologise for any inconvenience caused.
  • Thumbnail Image
    Histotripsy for the Treatment of Cholangiocarcinoma Liver Tumors: In Vivo Feasibility and Ex Vivo Dosimetry Study
    Hendricks-Wenger, Alissa; Weber, Peter; Simon, Alex; Saunier, Sofie; Coutermarsh-Ott, Sheryl; Grider, Douglas; Vidal-Jove, Joan; Allen, Irving C.; Luyimbazi, David; Vlaisavljevich, Eli (IEEE, 2021-09-01)
    Histotripsy is a noninvasive, nonionizing, and nonthermal focused ultrasound ablation method that is currently being developed for the treatment of liver cancer. Promisingly, histotripsy has been shown for ablating primary [hepatocellular carcinoma (HCC)] and metastatic [colorectal liver metastasis (CLM)] liver tumors in preclinical and early clinical studies. The feasibility of treating cholangiocarcinoma (CC), a less common primary liver tumor that arises from the bile ducts, has not been explored previously. Given that prior work has established that histotripsy susceptibility is based on tissue mechanical properties, there is a need to explore histotripsy as a treatment for CC due to its dense fibrotic stromal components. In this work, we first investigated the feasibility of histotripsy for ablating CC tumors in vivo in a patient-derived xenograft mouse model. The results showed that histotripsy could generate CC tumor ablation using a 1-MHz small animal histotripsy system with treatment doses of 250, 500, and 1000 pulses/point. The second set of experiments compared the histotripsy doses required to ablate CC tumors to HCC and CLM tumors ex vivo. For this, human tumor samples were harvested after surgery and treated ex vivo with a 700-kHz clinical histotripsy transducer. Results demonstrated that significantly higher treatment doses were required to ablate CC and CLM tumors compared to HCC, with the highest treatment dose required for CC tumors. Overall, the results of this study suggest that histotripsy has the potential to be used for the ablation of CC tumors while also highlighting the need for tumor-specific treatment strategies.
  • Thumbnail Image
    Host nutritional status affects alphavirus virulence, transmission, and evolution
    Weger-Lucarelli, James; Carrau, Lucia; Levi, Laura I.; Rezelj, Veronica V.; Vallet, Thomas; Blanc, Herve; Boussier, Jeremy; Megrian, Daniela; Coutermarsh-Ott, Sheryl; LeRoith, Tanya; Vignuzzi, Marco (2019-11)
    Malnourishment, specifically overweight/obesity and undernourishment, affects more than 2.5 billion people worldwide, with the number affected ever-increasing. Concurrently, emerging viral diseases, particularly those that are mosquito-borne, have spread dramatically in the past several decades, culminating in outbreaks of several viruses worldwide. Both forms of malnourishment are known to lead to an aberrant immune response, which can worsen disease outcomes and reduce vaccination efficacy for viral pathogens such as influenza and measles. Given the increasing rates of malnutrition and spread of arthropod-borne viruses (arboviruses), there is an urgent need to understand the role of host nutrition on the infection, virulence, and transmission of these viruses. To address this gap in knowledge, we infected lean, obese, and undernourished mice with arthritogenic arboviruses from the genus Alphavirus and assessed morbidity, virus replication, transmission, and evolution. Obesity and undernourishment did not consistently influence virus replication in the blood of infected animals except for reductions in virus in obese mice late in infection. However, morbidity was increased in obese mice under all conditions. Using Mayaro virus (MAYV) as a model arthritogenic alphavirus, we determined that both obese and undernourished mice transmit virus less efficiently to mosquitoes than control (lean) mice. In addition, viral genetic diversity and replicative fitness were reduced in virus isolated from obese compared to lean controls. Taken together, nutrition appears to alter the course of alphavirus infection and should be considered as a critical environmental factor during outbreaks.
  • Thumbnail Image
    Improved Therapeutic Delivery Targeting Clinically Relevant Orthotopic Human Pancreatic Tumors Engrafted in Immunocompromised Pigs Using Ultrasound-Induced Cavitation: A Pilot Study
    Imran, Khan Mohammad; Tintera, Benjamin; Morrison, Holly A.; Tupik, Juselyn D.; Nagai-Singer, Margaret A.; Ivester, Hannah; Council-Troche, McAlister; Edwards, Michael; Coutermarsh-Ott, Sheryl; Byron, Christopher; Clark-Deener, Sherrie; Uh, Kyungjun; Lee, Kiho; Boulos, Paul; Rowe, Cliff; Coviello, Christian; Allen, Irving C. (MDPI, 2023-05-24)
    Pancreatic tumors can be resistant to drug penetration due to high interstitial fluid pressure, dense stroma, and disarrayed vasculature. Ultrasound-induced cavitation is an emerging technology that may overcome many of these limitations. Low-intensity ultrasound, coupled with co-administered cavitation nuclei consisting of gas-stabilizing sub-micron scale SonoTran Particles, is effective at increasing therapeutic antibody delivery to xenograft flank tumors in mouse models. Here, we sought to evaluate the effectiveness of this approach in situ using a large animal model that mimics human pancreatic cancer patients. Immunocompromised pigs were surgically engrafted with human Panc-1 pancreatic ductal adenocarcinoma (PDAC) tumors in targeted regions of the pancreas. These tumors were found to recapitulate many features of human PDAC tumors. Animals were intravenously injected with the common cancer therapeutics Cetuximab, gemcitabine, and paclitaxel, followed by infusion with SonoTran Particles. Select tumors in each animal were targeted with focused ultrasound to induce cavitation. Cavitation increased the intra-tumor concentrations of Cetuximab, gemcitabine, and paclitaxel by 477%, 148%, and 193%, respectively, compared to tumors that were not targeted with ultrasound in the same animals. Together, these data show that ultrasound-mediated cavitation, when delivered in combination with gas-entrapping particles, improves therapeutic delivery in pancreatic tumors under clinically relevant conditions.
  • Thumbnail Image
    Investigation of High Frequency Irreversible Electroporation for Canine Spontaneous Primary Lung Tumor Ablation
    Hay, Alayna N.; Aycock, Kenneth N.; Lorenzo, Melvin F.; David, Kailee; Coutermarsh-Ott, Sheryl; Salameh, Zaid; Campelo, Sabrina N.; Arroyo, Julio P.; Ciepluch, Brittany; Daniel, Gregory; Davalos, Rafael V.; Tuohy, Joanne (MDPI, 2024-09-07)
    In this study, the feasibility of treating canine primary lung tumors with high-frequency irreversible electroporation (H-FIRE) was investigated as a novel lung cancer treatment option. H-FIRE is a minimally invasive tissue ablation modality that delivers bipolar pulsed electric fields to targeted cells, generating nanopores in cell membranes and rendering targeted cells nonviable. In the current study, canine patients (n = 5) with primary lung tumors underwent H-FIRE treatment with an applied voltage of 2250 V using a 2-5-2 µs H-FIRE waveform to achieve partial tumor ablation prior to the surgical resection of the primary tumor. Surgically resected tumor samples were evaluated histologically for tumor ablation, and with immunohistochemical (IHC) staining to identify cell death (activated caspase-3) and macrophages (IBA-1, CD206, and iNOS). Changes in immunity and inflammatory gene signatures were also evaluated in tumor samples. H-FIRE ablation was evident by the microscopic observation of discrete foci of acute hemorrhage and necrosis, and in a subset of tumors (n = 2), we observed a greater intensity of cleaved caspase-3 staining in tumor cells within treated tumor regions compared to adjacent untreated tumor tissue. At the study evaluation timepoint of 2 h post H-FIRE, we observed differential gene expression changes in the genes IDO1, IL6, TNF, CD209, and FOXP3 in treated tumor regions relative to paired untreated tumor regions. Additionally, we preliminarily evaluated the technical feasibility of delivering H-FIRE percutaneously under CT guidance to canine lung tumor patients (n = 2). Overall, H-FIRE treatment was well tolerated with no adverse clinical events, and our results suggest H-FIRE potentially altered the tumor immune microenvironment.