Evaluating the expression and regulation of the IgG Fc receptors CD16 and CD64 on canine leukocytes.
Natural killer (NK) cells are cytotoxic lymphocytes of the innate immune system, and they play an important role in killing cancer cells by a process referred to as antibody-dependent cell-mediated cytotoxicity (ADCC). This is mediated by the IgG Fc receptor CD16. CD64 is another important IgG Fc receptor expressed by other leukocyte populations in humans. For dogs, few effective cancer immunotherapies have been developed and their immune system not been as well characterized as the human and mouse immune systems. Interesting is that dogs develop certain cancers similar to humans, such as osteosarcoma, leukemia and lymphoma. This study focuses on the further characterization of the dog immune system. Our focus was on the expression and regulation of CD16 and CD64 on dog leukocytes. This was done by using novel antibodies that detect canine CD16 and CD64 to examine their expression on resting and activated leukocytes. Dog leukocytes were isolated from the peripheral blood of healthy animals and examined in the presence or absence of phorbol myristate acetate (PMA), a potent cell activating agent. The dog leukocytes were stained with anti-CD16, anti-CD64, and control antibodies, evaluated by flow cytometry, and data analyzed using the software, FlowJo. These results will be discussed in my poster presentation.