Proteomic Serum Profiling of Holstein Friesian Cows with Different Pathological Forms of Bovine Paratuberculosis Reveals Changes in the Acute-Phase Response and Lipid Metabolism

Abstract

The lack of sensitive diagnostic methods to detect Mycobacterium avium subsp. paratuberculosis (Map) subclinical infections has hindered the control of paratuberculosis (PTB). The serum proteomic profiles of naturally infected cows presenting focal and diffuse pathological forms of PTB and negative controls (n = 4 per group) were analyzed using TMT-6plex quantitative proteomics. Focal and diffuse are the most frequent pathological forms in subclinical and clinical stages of PTB, respectively. One (focal versus (vs.) control), eight (diffuse vs. control), and four (focal vs. diffuse) differentially abundant (DA) proteins (q-value < 0.05) were identified. Ingenuity pathway analysis of the DA proteins revealed changes in the acute-phase response and lipid metabolism. Six candidate biomarkers were selected for further validation by specific ELISA using serum from animals with focal, multifocal, and diffuse PTB-associated lesions (n = 108) and controls (n = 56). Overall, the trends of the serum expression levels of the selected proteins were consistent with the proteomic results. Alpha-1-acid glycoprotein (ORM1)-based ELISA, insulin-like growth factor-binding protein 2 (IGFBP2)-based ELISA, and the anti-Map ELISA had the best diagnostic performance for detection of animals with focal, multifocal, and diffuse lesions, respectively. Our findings identify potential biomarkers that improve diagnostic sensitivity of PTB and help to elucidate the mechanisms involved in PTB pathogenesis.

Cathepsin S Is More Abundant in Serum of Mycobacterium avium subsp. paratuberculosis-Infected Dairy Cows

“…This methodic procedure differed strongly from our enhanced label-free analyses and had, therefore, led to a limited number of identified proteins. Another serum proteomics study already detected 669 quantified proteins in bovine serum, of which only nine proteins showed significantly different abundances in MAP-infected cattle compared to the control group [83]. One of these nine proteins, fetuin B, also showed a significantly different abundance in our study.…”

Celebrating Women in Proteomics and Metabolomics

“…Studies presented in this Special Issue have also delved into understanding pathogen infections and antimicrobial activities in different hosts and systems. Quantitative proteomics of serum samples led by Alejandra Isabel Navarro Leon from the Rosa Casais group pointed to the regulation of certain proteins in pathological forms of bovine paratuberculosis . A study from the group of Leslie Hicks characterized the still understudied antimicrobial peptides expressed in plants, pointing to a new subfamily of α-hairpinins .…”