Effects of ketones, acetate, and glucose on in vitro immunoglobulin secretion by bovine lymphocytes

Individual and combined effects of ketones, acetate, and glucose on IgM secretion by bovine blood lymphocytes were evaluated in vitro. Supernatants from 14-d cultures of unstimulated and mitogen- or antigen-stimulated mono-nuclear leukocytes were harvested and analyzed for total and antigen-specific IgM. Ketones, acetate, and 1,3-butanediol individually added up to 6.25 mM had no effect on total IgM secreted by cells grown in medium containing 11.1 mM glucose. However, butyrate at 6.25 mM inhibited IgM secretion. Addition of a mixture of ketones approximating plasma levels of severely ketotic cows inhibited mitogen-induced IgM secretion in 11.1 mM glucose-supplemented cultures. Results from experiments evaluating effects of glucose concentrations on IgM secretion indicated that plasma glucose concentration associated with the ketotic state (1.66 mM), compared with normal plasma glucose concentration (3.33 mM), did not affect total or antigen-specific IgM secretion. Supplementation of cultures containing up to 3.33 mM glucose with ketones, acetate, or both either had no effect or a modest stimulatory effect. These data indicate that effects of ketones and acetate on IgM secretion are dependent on the concentration of glucose in culture and suggest that changes in plasma glucose, ketone, and acetate concentrations associated with bovine ketosis do not alter IgM secretion in vivo.