Integrating Analysis of Publicly Available Microarray Data to Study the Immune Response of Cattle to Infection with Mycobacterium bovis

Bovine tuberculosis is one of the serious public health challenges which also causes economic damage in the livestock industry. Understanding the interaction mechanism between the host immune system and the causative pathogen of tuberculosis is one of the essential areas of study for success in designing effective drugs to treat tuberculosis. Here, we used four publicly available microarray data to light up the response of the cattle immune systems to Mycobacterium bovis at the gene level. Our integrating analysis results on microarray data led to identifying 189 (160 up- and 29 down-regulated) differentially expressed genes for infected samples with Mycobacterium bovis against uninfected samples. Gene ontology and pathway analysis indicated that most of the differentially expressed genes are related to the immune system’s (especially innate immune system) response to the pathogen. Finally, 122 proteins (108 up-regulated and 14 down-regulated) were included in the constructed protein-protein interaction network among the proteins from differentially expressed genes. We identified 11 genes as hub genes based on three methods using the cyto Hubba plug-in in the Cytoscape. Based on our analysis, most differentially expressed genes are related to the innate immune system. However, considering the impact of time on the microarray data analysis indicated that associated gene expression with the adaptive immune system increased by time.