Investigating the Mechanisms Behind Immune Responses in Beef Cattle
Project Title
Determining Whether Invariant Natural T Cells Play a Role in Immune Responses in Cattle
Researchers
Emma Borkowski [email protected]
Janet Beeler-Marfisi, Ontario Veterinary College
| Status | Project Code |
|---|---|
| In progress. Results expected in April, 2026 | POC.09.24 |
Background
Most infectious diseases enter through a mucosal surface, usually the respiratory or gastrointestinal tract. Immune responses in the respiratory mucosa are the first line of defence against bovine respiratory disease (BRD). Antibodies bind inhaled pathogens, preventing them from invading the respiratory tract, and stimulating the immune response. However, most BRD vaccines target T helper cells that promote systemic antibody responses in the blood and lymphatic systems, not the surface of the respiratory tract, and a systemic immune response does not produce a strong mucosal immune response. In cattle, systemic responses are mediated by immunoglobulin (Ig)G, while those at mucosal surfaces primarily consist of IgA. Development of a systemically administered BRD vaccine that targets cells involved in mucosal antibody responses could overcome limitations of existing BRD vaccines. Invariant natural killer T (iNKT) cells may offer a possible solution.
Vaccines that target iNKTcells could produce greater immunologic stimulation than vaccines that stimulate T helper cells. In humans and mice, iNKT cells have been identified in the spleen, liver, lung, and enteric mucosa. Activated iNKT cells drive production of both IgG and IgA and are more abundant than T helper cells. However, the first step is to find and characterize iNKT cells in cattle.
Objectives
- Determine whether methods for isolation of iNKT cells from peripheral blood of humans are valid in cattle
- Adapt methods for culture of human iNKT cells for cattle iNKT cells
What they will do
Blood will be collected from the tail or jugular vein of healthy adult cattle at the Ontario Beef Research Centre. Peripheral blood mononuclear cells (PBMCs) will be isolated.
Two antibodies that have been used to successfully isolate iNKT cells in humans and mice will be used to search for iNKT cells in the cattle samples. Bovine iNKT cells will then be isolated and quantified.
Implications
This project will determine whether iNKT cells exist in cattle and potentially will enable progress towards more effective vaccination strategies to reduce the economic impact of BRD in beef cattle.