Validation of the Postprandial Interleukin-1β Response in Horses Using Equine-Specific Antibodies

Interleukin (IL)-1β is a commonly studied proinflammatory cytokine, with relevance to arthritis, obesity, aging, and other inflammatory diseases of horses. Evaluating protein concentrations in plasma is a useful measurement for research in these areas of equine health. The objective of this research was to validate a commercially available enzyme-linked immunosorbent assay (ELISA) for equine IL1β and to compare concentrations with those previously published using an ELISA that is no longer available. The ELISA was assessed for linear parallelism and recovery using plasma from four healthy Standardbred mares. The assay was found to have linear parallelism for samples diluted 1:2, when the detection antibody concentration was 3 μg/mL. The average recovery of spiked IL1β was 98.9%. To compare concentrations, plasma was collected from six geldings at −0.5, 1, 2, and 4 hours after consumption of a meal high in starch and sugar (1.2 g/kg bodyweight). Consumption of 1.2 g of starch and sugar per kg of BW increased plasma IL1β concentrations 1 hour after feeding (P = .053). In conclusion, the commercially available ELISA is validated, with modifications, for use in equine plasma, and it detects a rise in plasma IL1β concentrations at 1 hour after meal consumption, a finding that is similar to previously reported data.