Intranasal vaccination of young Holstein calves with Mannheimia haemolytica chimeric protein PlpE–LKT (SAC89) and cholera toxin

We have previously documented that a single dose of feG–COOH prior to allergen challenge significantly decreased eosinophilic airway inflammation in cats with experimental asthma, but did not result in complete resolution of airway inflammation. This study was undertaken to determine if a chronic (2 weeks) course of feG–COOH in experimentally asthmatic cats would induce complete remission of airway inflammation and clinical signs of asthma. Experimental asthma was induced using Bermuda grass allergen (BGA) and cats were randomly selected to receive either feG–COOH (1 mg/kg, PO) or saline for 2 weeks, followed by a 2-week washout period. Cats then received the alternate treatment. Aerosol challenge with BGA was performed weekly throughout the study and bronchoalveolar lavage fluid (BALF) and blood were collected prior to and after each of the 2-week treatment periods. Regular use of feG–COOH had no significant effect on airway inflammation, BALF and plasma TNF bioactivity or a clinical sign compared to placebo. Regular use of feG–COOH can thus not be recommended as the sole therapy for feline allergic asthma.