Quantitative proteomics of cow milk during sub clinical mastitis and analysis of protein interactome network

Abstract

Bovine milk is vital for infant nutrition and is a major component of human diet. Bovine mastitis is a common inflammatory disease of mammary glands in cattle. It alters immune profile of animal, low quality and yield of milk causing huge economic losses to dairy industry. The incidence of subclinical mastitis (SCM) is higher (25 65% worldwide) than clinical mastitis (CM) (gt5%) and frequently progresses to clinical stage due to lack of sensitive detection method. We used quantitative proteomics to identify changes in milk during subclinical mastitis during summer and winter seasons to develop a rapid, non-invasive, sensitive detection method. We performed a comparative proteome analysis of the bovine milk collected from the Indian hybrid cow Karan Fries. The milk differential proteome of hybrid cow during sub-acute and clinical intramammary gland infection has not been investigated to date in different seasons. Using high-resolution mass spectrometry-based quantitative proteomics of the bovine whey proteins, we identified a total of 2224, 2873 proteins out of 220 and 332 proteins were differentially expressed between normal and SCM and CM infected samples in summer and winter season respectively. Out of 220 DEPs, 82 proteins were significantly up-regulated and 27 proteins were down regulated having fold change and#8805;1.4 and and#8804; 0.8 respectively. Out of 332 proteins, 134 were up-regulated and 67 were down-regulated proteins having and#61502;1.5 to and#8804; 0.8 respectively in winter season. The over-expression of CHI3L1, LBP, GSN, GCLC, C4, PIGR, HSP90, CATH6and7 and CSTB was positively correlated with elicited host defense system by producing cytokines and inflammatory molecules. The appearance of these potential biomarkers in milk can be used to segregate affected cattle from normal herd and initiate mitigation measures for SCM. This would stop their progression into clinical stage of mastitis and maintenance of milk quality using non-invasive approaches. newline