Browsing by Author "Galezowski, Angelica"

Now showing 1 - 3 of 3
  • Thumbnail Image
    ItemOpen Access
    Conditionally immortalizing porcine hematopoietic stem cells using a Hox-B8 retrovirus and characterizing the porcine bone marrow niche
    (2022-05-24) Chiriboga Proano, Jose A; Warren, Amy L; Gilch, Sabine; DeVinney, Rebekah; Galezowski, Angelica; Jenne, Craig
    Studies in the field of veterinary immunology have been hampered by the availability of species-specific research tools that yield more reliable and accurate experimental planning and results. Limited resources exist to study and understand immune cells, such as macrophages, in pigs and other domestic species. Porcine immune cells are often derived in vitro and require isolation from the blood or bone marrow of live animals. The goal of this research project was to conditionally immortalized hematopoietic stem cells in pigs that can produce all immune cells by using an estrogen-controlled Hox-B8 lentivirus. In the presence of estrogen and expression of HoxB8, hematopoietic stem cells would remain in a conditionally immortalized progenitor stage. With removal of estrogen and addition of appropriate cytokines, hematopoietic stem cells would differentiate into a spectrum of common porcine immune cells. To be able to conditionally immortalize the hematopoietic stem cells and prime these cells to differentiate into in vitro, we first had to develop mammalian cell lines capable of expressing and secreting porcine recombinant cytokines - the second aim of this thesis. Methods to isolate porcine bone marrow and create media and conditions to culture bone marrow in the lab were also created in this project, which further allowed us to gain insight into hematopoiesis and the niche microenvironment in pigs.
  • Thumbnail Image
    ItemOpen Access
    Impact of Age and Duration of Maternal Separation on Processing Stress and Vaccine Responses in Pre-weaned Beef Calves
    (2022-06) Silas, Haley; Pajor, Edmond; Windeyer, Claire; Galezowski, Angelica; Janzen, Eugene
    Spring processing is a common practice in western Canadian cow-calf herds that involves separating calves from their dams and restraining the calves while they receive a combination of procedures that may include vaccination, castration, branding, and dehorning. Spring processing events are thought to be stressful for the calf; however, the impact of their age and the duration of maternal separation is not known. The first study (Chapter 2) assessed impacts of age and duration of maternal separation on stress experienced by calves at processing. It was found that four- and eight-week old calves had similar behavioural indicators of stress and cortisol concentrations after processing. Calves separated for five hours before processing were less active after processing than calves separated for one hour before processing. This decrease in activity in calves separated for longer could indicate they have become exhausted or acclimatized to their pen. The second study (Chapter 3) assessed the impact of age and stress on immunoglobulin G (IgG) and immunoglobulin M (IgM) antibody responses to intranasal vaccination with a modified live vaccine against bovine herpesvirus type 1 (BHV1), parainfluenza virus type 3 (PIV3), and bovine respiratory syncytial virus (BRSV; Inforce3®, Zoetis Inc., New Jersey, USA). In this study, BRSV, PIV3, and BHV1 IgG concentrations remained relatively similar from baseline to post-vaccination, while BRSV, PIV3, and BHV1 IgM concentrations increased during the same period. Furthermore, this increase was greater in eight-week old calves than four-week old calves, potentially because old calves were more responsive immunologically than the younger calves. Cortisol concentration proved to have minimal association with antibody concentrations after vaccination, with only some weak positive correlations between cortisol at certain timepoints and BRSV IgG or BHV1 IgG concentrations post-vaccination. Overall, there was no difference between vaccinated and unvaccinated calves, suggesting that maternally derived antibodies may have prevented a detectable humoral immune response to vaccination. To our knowledge, this study was the first to consider IgG and IgM immune responses to vaccination at industry-relevant processing ages.
  • Thumbnail Image
    ItemOpen Access
    The Use of Telepathology in Veterinary Medicine: A Scoping Review Protocol
    (2021-11-26) Rogers, Lindsay; Ganshorn, Heather; Galezowski, Angelica; Goldsmith, Dayna; Legge, Carolyn; Davies, Jennifer
    Background: Telepathology, as a subset of teleconsulting, is pathological interpretation performed at a distance. Diagnostics can be difficult to access by rural veterinary practices yet are vital to the health of production animal herds often serviced by these practices. The technology and availability of telepathology services has not been assessed to identify gaps in the literature and means of improving diagnostics services to rural veterinary clinics. Objectives: The objective of this scoping review is to provide an overview of how telepathology is being used in veterinary medicine. Eligibility criteria: Peer reviewed journal articles and grey literature in the English language and published after 2000 will be included in the study. It must be relevant to performing pathological interpretation at a distance in veterinary medicine. Literature about radiology, bacteriology, and relevant to human medicine will be excluded. Sources of evidence: Searches will be conducted in CAB Abstracts and MEDLINE. Websites from national veterinary medical associations, veterinary pathologist membership organizations, and international animal health organizations will be searched for grey literature. Charting methods: Data charting will include study characteristics, sector of pathology, technology used for communication, technology used for pathological interpretation, and a summary of the literature objectives and conclusions.