Proteomics of pulmonary disease in Westies

Maher RE, Määttä M, Beynon RJ, Laurila HP, McNamara PS, Rajamäki MM. (2022) Quantitative proteomic analysis of bronchoalveolar lavage fluid in West Highland white terriers with canine idiopathic pulmonary fibrosis.
BMC Vet Res. 2022 Mar 30;18(1):121. doi: 10.1186/s12917-022-03202-x.

BACKGROUND: Canine idiopathic pulmonary fibrosis (CIPF) is a chronic,
progressive, interstitial fibrosing lung disease, manifesting as cough, exercise
intolerance and ultimately, dyspnea and respiratory failure. It mainly affects
West Highland white terriers (WHWTs), lacks curable treatment and has a poor
prognosis. Aspiration of gastroesophageal refluxate may play a role in the
development of CIPF. In the first part of this study, we completed label-free
quantitative proteomic analysis of bronchoalveolar lavage fluid (BALF) from CIPF
and healthy WHWTs. In the second part, we evaluated potential protein markers of
reflux aspiration from canine gastric juice and vomitus and whether these were
present in BALF from the two groups.
RESULTS: Across all BALF samples, 417 proteins were identified, and of these,
265 proteins were identified by two or more unique tryptic peptides. Using the
265 high confidence assignments, the quantitative proteome profiles were very
similar in the two cohorts, but they could be readily resolved by principal
component analysis on the basis of differential protein expression. Of the
proteins that were differentially abundant in the two groups, several (including
inflammatory and fibrotic markers) were elevated in CIPF, and a smaller, more
diverse group of proteins were diminished in CIPF. No protein markers indicative
of reflux aspiration were identified.
CONCLUSIONS: Label-free proteomics allowed discrimination between CIPF and
healthy WHWTs, consistent with fibrotic process but did not provide clear
evidence for gastrointestinal aspiration. The measurement of proteins may
provide a proteomics signature of CIPF that could be used to evaluate treatment
options.