INFLAMMATORY MARKERS IN BRONCHOALVEOLAR LAVAGE FLUID OF STANDARD-BREDRACEHORSES WITH INFLAMMATORY AIRWAY DISEASE - RESPONSE TO INTERFERON-ALPHA

Protein and eicosanoid concentrations and procoagulant activity were d etermined in bronchoalveolar lavage fluid (BALF) from 32 Standardbred racehorses with inflammatory airway disease (IAD) and 6 control horses , Total protein, albumin and immunoglobulin G (IgG) concentrations wer e high (P<0.05) in the BALF from horses with IAD, a finding consistent with exudation of plasma protein into the airway, Immunoglobulin A (I gA) concentrations also were increased (P<0.05) which may signify loca l immunoglobulin production, Difference was not detected in prostaglan din E-2 and 6-ketoprostaglandin F-1 alpha concentrations in BALF of IA D-affected and control horses, Procoagulant activity was identified in the majority (66%) of BALF samples from IAD affected horses and was n ot detected in control horses, Natural human interferon-alpha (nHuIFN alpha) (placebo, 50, 150, or 450 units) was administered orally for 5 days to IAD-affected horses in a double-blind, randomised block design , Total protein, IgG, and IBA concentrations in BALF were reduced (P<0 .05) 8 days after administration of 50 u and 150 u nHuIFN alpha, and 1 5 days after administration of 50 u nHuIFN alpha, Procoagulant activit y and albumin concentrations in BALF were lower 8 days after administr ation of 50 u nHuIFN alpha. Oral administration of low-dose nHuIFN alp ha appeared to ameliorate these parameters of lower respiratory tract inflammation in Standardbred racehorses with IAD.