Performing Department
(N/A)
Non Technical Summary
For dairy cows, proper function of fat tissue is critical for supporting the health and productivity of these animals, especially at the onset of lactation when cows must deal with significant metabolic stress that can lead to inflammation, disease, and economic losses. Macrophages, the most abundant immune cells in fat tissue, and endothelial cells, which support blood flow into and out of fat tissue, are important cells that help guide the functions of fat tissue and play important roles in metabolism and inflammation. However, the changes that occur in these cell types and how they interact with each other as dairy cattle go from being pregnant to lactating, and when dairy cattle experience metabolic stress, have yet to be fully understood. Our hypothesis is that changes in both the abundance and functions of macrophages and endothelial cells within fat tissue of dairy cattle are involved in the development of metabolic stress and the adaptation required of dairy cattle during the transition from pregnancy to lactation.To investigate the macrophage and endothelial cells in fat tissue, we will collect fat tissue samples from dairy cattle both before and after calving as well as from dairy cows at the beginning of lactation that are experiencing metabolic stress. Macrophages and endothelial cells will be isolated from these fat tissue samples and evaluated for their overall abundance as well as potential changes in their function and genetics as cows transition from pregnancy to lactation. In addition, techniques will be used to understand how the macrophages and endothelial cells in fat tissue interact and how these interactions may differ during pregnancy and early lactation, as well as in cows that are experiencing metabolic stress. By furthering our understanding of the role that macrophages and endothelial cells play in the fat tissue of dairy cows, we may identify new targets for potential therapeutics for improving the health and productivity of dairy cattle during early lactation.
Animal Health Component
(N/A)
Research Effort Categories
Basic
100%
Applied
(N/A)
Developmental
(N/A)
Goals / Objectives
For the training and development component of this project, the major goal is to prepare Dr. Hunter Ford for a career as an independent researcher. This goal contains the following objectives:Train Dr. Hunter Ford in the necessary research abilities and techniques for developing and engaging in future independent research projects.Develop Dr. Hunter Ford's professional skills and professional network so that he is a highly competitive candidate for potential job opportunities as an independent researcher.For the research component of this project, the major goal is to improve the health and productivity of dairy cows during the peripartum period by elucidating the roles of macrophages and endothelial cells in adipose tissue. In pursuit of this goal, this project contains two primary objectives:Characterize the transcriptomic and functional changes in macrophages and endothelial cells as dairy cows transition from late gestation to early lactation.Delineate the crosstalk between adipose tissue resident macrophages and endothelial cells in dairy cows with and without hyperketonemia in the early postpartum period
Project Methods
The training and development component of this project will focus on preparing Dr. Hunter Ford for a successful career as an independent researcher. Dr. Ford will receive primary mentorship and training from Dr. Clarissa Strieder-Barboza with support from the collaborating mentor, Dr. Carey Lumeng. Working in the Strieder-Barboza lab, Dr. Ford will receive extensive training in a wide range of techniques including adipose tissue biopsy and sample collection from dairy cows, transcriptomic analysis, flow cytometry, cell culture, cellular functional assays, and data analysis. Dr. Ford will also participate in the mentorship of undergraduate and graduate students and will continue the development of his teaching and communication skills by lecturing in courses associated with animal healthy, livestock immunology, and livestock disease. Dr. Lumeng will provide important technical expertise relating to adipose tissue macrophages and immunometabolism. Working with Dr. Lumeng, Dr. Ford will also present and discuss his research findings with members of the Lumeng lab. Dr. Ford will also participate in important professional development activities, including NIH workshops on flow cytometry, grant writing workshops, and career counseling sessions through Texas Tech University.Evaluation: Dr. Ford's training and development will be evaluated regularly via weekly one-to-one meetings with Dr. Strieder-Barboza, and quarterly with Dr. Lumeng. Dr. Ford's technical training and expertise will be assessed throughout this project on the basis of successful completion of experiments, responsible research practices, proper experiment design and data interpretation. Important milestones for Dr. Ford's training and development include successful completion of technical and grantsmanship workshops and career counseling sessions. Dr. Ford's development as a mentor will be evaluated based on the progress of the undergraduate and graduate students he is working with and will be measured through the successful publication of manuscripts co-authored by Dr. Ford and the students, as well as through successful presentation of research findings by student mentees at local and national conferences. Dr. Ford's teaching proficiency will be measured via student evaluations, as well as by other members of the Veterinary Sciences department at Texas Tech University.This research project will evaluate the adipose tissue resident macrophage and endothelial cells in dairy cattle using two cohorts of cows.The first cohort of cows will include 12 clinically healthy dairy cattle and subcutaneous adipose tissue samples will be collected from the flank of cows during both the late prepartum (-30 and -7 days relative to parturition) and early postpartum (+7 days relative to parturition) periods. Macrophages and endothelial cells will be isolated from these adipose tissue samples and will be evaluated for their abundance within adipose tissue as well as their transcriptomic and functional characteristics. Results will be analyzed via comparison between the three sampling dates. Using this cohort of dairy cattle, we will provide valuable insight into how changes within adipose tissue resident macrophage and endothelial cell populations contribute to the adaptation required of dairy cattle, and specifically the adipose tissue of dairy cattle, as these animals transition from pregnancy to lactation.The second cohort of cows will consist of cows between +4 and +10 days postpartum, 10 of which will be clinically healthy and 10 will have been diagnosed with hyperketonemia (blood BHB ≥ 1.2 mM). Hyperketonemia, a common sign that dairy cattle are dealing with significant metabolic stress, is largely driven by adipose tissue dysfunction, and is one of the most common metabolic diseases of early postpartum dairy cows. Subcutaneous adipose tissue will be collected from these cows after they have been selected for the study in the same manner utilized for the first cohort of cows. Adipose tissue resident macrophages and endothelial cells will be isolated and evaluated following the same procedures. In addition, macrophages and endothelial cells will be cultured and the resulting media from these cell cultures will be used to treat the opposing cell type (ex. Macrophage-conditioned media will be used to treat endothelial cells), with crosses of samples from healthy and hyperketonemic cows included as well (ex. Macrophage-conditioned media from macrophages isolated from hyperketonemic cows will be used to treat endothelial cells isolated from healthy cows). These indirect co-culture models will be used to evaluate the effects that the different cell types, within the context of metabolic disease, have on the function of each other. Overall, using this second cohort of dairy cattle will provide valuable insight into the roles of both macrophages and endothelial cells within adipose tissue in the development of metabolic disease during the early postpartum period.Efforts: Knowledge and findings pertaining to these studies will be disseminated through peer-reviewed publications and conference proceedings. Valuable insights will also be shared with local dairy farmers and incorporated into relevant classes for students studying immunology, dairy production, and metabolism.Evaluation: This project will be evaluated on a regular basis to ensure timely completion of the objectives. Important measurable milestones include the generation of transcriptomic data related to macrophage and endothelial cells populations and their publication in the NCBI Gene Expression Omnibus repository, presentation of findings in at least 2 academic research conferences per year, publication of at least 2 peer-reviewed research manuscripts, lectures in undergraduate and graduate level courses to discuss experimental findings, and presentations to colleagues and stakeholders via university meetings or on-farm discussions.