Staphylococcus Aureus Elicit an Increased Expression of TLR9 Gene to the Innate Immune Response in Bovine Mastitis

Abstract

Mastitis in dairy cattle caused by S. aureus infection may eventually turn into a chronic disease with a lifelong persistence of the bacteria. TLR9 plays a crucial role in cell survival through recognition of various bacterial components. This study was carried out to assess the expression of TLR9 gene in spontaneous bovine sub-clinical and clinical mastitis caused by S. aureus. RNA isolated from milk somatic cells was converted as cDNA using oligo (dT) primers. Quantitation of mRNA of TLR9 was analysed by RT-qPCR system. The mRNA expression of TLR9 gene in sub-clinical mastitis was higher (3.71 fold) than clinical case (1.15 fold) when compared to normal bovine case. The expression of TLR9 gene at high level during sub-clinical stage of infection, may be subsided itself without precipitating into clinical mastitis. The results presented would facilitate deeper insight into the specific regulatory mechanisms of TLR9 mediated signalling cascades to elucidate host immune response against bovine mastitis.