|Fach, Sasha - IA STATE UNIV., AMES, IA|
|Davis, William - WA STATE UNIV., PULLMAN|
Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: September 21, 2001
Publication Date: N/A
Technical Abstract: Peripheral blood mononuclear cells (PBMC) were isolated from female white- tailed deer fawns at 48 hours of age and every two weeks there after until the fawns were three months of age. Lymphocytes were phenotyped to examine development and expression of specific surface receptors as the fawns aged. Three-color flow cytometric analysis of leukocytes was performed using a panel of monoclonal antibodies. Included in the panel were WC1, gamma chain, delta chain, CD4, CD8, CD62L, CD44, CD21, IL-2R, MHC Class II, B-B1, B-B2 and B-B4 monoclonal antibodies. Analysis revealed dynamic changes in the expression of specific surface receptors associated with development and maturation of lymphocyte subpopulations. Evaluation of WC1+ gamma delta T cells within the first two weeks of age revealed intermediate and bright populations of the delta chain in some fawns. The intermediate population disappeared by eight weeks of age and may represent a differential stage of WC1+ gamma delta T cell development. CD4 and CD8 populations became more predominate by four weeks of age. B cell surface IgM expression was heterogeneous at two days of age but became more discrete as the fawns matured. Expression of B-B2, a B cell lineage marker, disappeared as the fawns aged. However, expression of another B cell lineage marker, B-B4, increased with age. Proliferative capabilities of the isolated PBMC's to pokeweed mitogen (PWM), Concanavalin A (ConA) and Mannheimia (Pasteurella) haemolytica LPS were also examined. The cell response to PWM and ConA was similar to that of adult white-tailed deer, but the response to LPS was minimal unlike the adults. Little is known about lymphocyte development in white-tailed deer fawns, and these findings provide basic information on the characterization of their leukocytes.