Molecular insights into the neutrophils activation in zebu cattle during seasonal variation

Abstract Earlier, we reported the impact of season on neutrophils’ functional competence and also hypothesized that it could be the impact of different seasons on neutrophils’ activation. In cerebration, the present study aimed to provide insights into neutrophils’ activation in terms of phosphorylation of tyrosine containing proteins during different seasons. Ten Hariana cows participated in the study and eight times blood samples were collected from each animal (twice in each month) during each season. Phosphorylation of tyrosine proteins was evaluated using western blotting and immunolocalization using a fluorescent microscope. Immuno blotting identified six tyrosine-phophorylated proteins p28, p42, p44, p58, p84, and p104 in winter and rainy seasons, whereas, p84 protein was absent in summer season. Immunolocalization revealed positive immune reactivity (IR) for tyrosine-phosphorylated proteins and significantly (p < 0.05) lower percent of neutrophils showed positive IR during the summer season as compared to winter and rainy seasons. The results of the study evidently indicate the activation of neutrophils is mediated through tyrosine phosphorylation and this may be a probable reason behind the decreased neutrophils’ functional competence during the summer. Further studies are warranted to decipher the possible association between tyrosine phosphorylation and expression of surface receptors required for the recruitment of neutrophils.