Successful reproduction is essential for milk production and for generating replacement animals for dairy herds. However, there has been a gradual decline in reproductive efficiency of dairy cows, resulting in substantial economic loss to farmers. Most failed pregnancies are due to embryonic death, which could be due to inadequate function of the corpus luteum (CL). The CL is a structure on the ovary that secretes progesterone, which is essential for survival of the embryo. The long term goal of this research program is to increase understanding of the function of the bovine corpus luteum (CL). Immune cells are present in the CL and serve as local regulators of the function of the CL, but very little is known about the types of communication that occur between the progesterone-producing cells and the immune cells. The global hypothesis to be addressed is that the progesterone-producing cells in the CL communicate with the resident immune cells via secretion of microscopic (extracellular) vesicles, which transfer proteins and nucleic acids directly to the immune cells, thus programming the functional capabilities of the resident immune cells. To test this hypothesis, cells from the CL will be cultured and the secreted extracellular vesicles will be isolated from the culture medium. The vesicles will be used to treat immune cells, and the effect of the vesicles on immune cell functions, including gene and protein expression, will be determined. Further, we will determine if regulation of the immune cells by the vesicles is altered during the early stages of pregnancy. Finally, the protein and nucleic acid content of the vesicles will be defined in an effort to identify the molecules that regulate immune cell function. It is expected that these molecules will differ in cells from pregnant compared to nonpregnant cows. These will be the first reports of how the hormone-producing cells within the CL communicate with immune cells to regulate the overall function of the tissue. Understanding how immune cells that populate the CL are regulated could ultimately lead to new methods to enhance reproductive efficiency of dairy cows and lower the costs of food production.
|Effective start/end date
|2/1/16 → 1/31/22
- National Institute of Food and Agriculture: $460,000.00