Evaluation of biomarkers in bronchoalveolar lavage fluid for discrimination between asthma and chronic bronchitis in cats.

OBJECTIVE: To compare concentrations of interleukin (IL)-4, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha and total nitric oxide (NO) metabolites in bronchoalveolar lavage fluid (BALF) for discrimination between asthma and chronic bronchitis in cats. ANIMALS: 97 cats. PROCEDURES: Cats screened with cytologic examination of BALF included 13 client-owned cats with naturally developing asthma, 8 client-owned cats with chronic bronchitis, 23 research cats with experimentally induced asthma, 33 research cats with experimentally induced nonseptic suppurative inflammation of the airways, and 20 healthy control cats. Banked unconcentrated BALF supernatant samples were assayed for concentrations of IL-4, IFN-gamma, TNF-alpha, and total NO metabolites. RESULTS: Concentrations of IL-4 and IFN-gamma in BALF were less than the limits of detection for most cats, precluding statistical analysis. No significant differences were detected among groups for TNF-alpha concentrations. Concentrations of total NO metabolites were significantly higher in cats with clinical chronic bronchitis, compared with research cats with nonseptic suppurative inflammation or research cats with asthma. CONCLUSIONS AND CLINICAL RELEVANCE: There were no significant differences in tested biomarkers between cats with asthma and healthy control cats. None of the measured cytokines or NO metabolites were useful for discriminating between cats with naturally developing asthma and those with chronic bronchitis.

Chronic use of the immunomodulating tripeptide feG-COOH in experimental feline asthma.

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 (1mg/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.

Prevalence of selected infectious disease agents in cats from Arizona.

The objective of this study was to use polymerase chain reaction (PCR) assays to determine the prevalence of Ehrlichia species, Anaplasma phagocytophilum, Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum' and Bartonella species from feral and relinquished cats in Phoenix and Nogales, Arizona. DNA from one or more of the organisms was amplified from 31 of 112 blood samples (27.7%). DNA consistent with Bartonella clarridgeiae 15 (13.4%), Bartonella henselae 14 (12.5%), 'Candidatus M haemominutum' 9 (8.0%), and M haemofelis 5 (4.5%) were detected. DNA of Ehrlichia species, Neorickettsia risticii, or A phagocytophilum was not amplified. Failure to amplify DNA of A phagocytophilum may relate to the absence of appropriate tick vectors. Failure to amplify Ehrlichia species DNA suggests that cats were not exposed, exposed but not infected, or infected but the DNA was not detected by the PCR assay used in this study. The Bartonella species and hemoplasma results suggest flea control should be maintained.