Expression profiling of cytokine-related genes in Brucella abortus infected cattle

ABSTRACT

The present investigation was undertaken to assess the rhythmic change in the expression profile of cytokine-related genes in the PBMC of Brucella abortus infected cattle. The whole blood samples were collected from cattle from the state of Rajasthan in Western India. All 20 samples of PBMC cultured cells from the 10 diseased cattle serologically positive for brucellosis, and 10 serologically negative healthy controls, were harvested, and the expression of cytokine-related genes was normalized relative to β-actin for their quantification by SYBR green-based real-time PCR. The subsequent analysis was based on the comparisons within treatment group (unstimulated or B. abortus stimulated) and between infection groups (healthy control versus diseased). The expression profiling of cytokine genes revealed differential expression of IFN-γ, TNF-α, IL-1β, IL-4, IL-6, IL-12p40 and iNOS by PBMCs from healthy cows and Brucella positive cows even without stimulation with Brucella abortus antigen. This unique expression profile with enhanced expression of genes encoding IFN-γ, IL-1β, IL-6 and iNOS, and reduced expression of TNF-α, IL-4 and IL-12p40; indicates changing of the dynamic immune responses from a predominantly Th1-like pattern to a Th2-like pattern with the development of a chronic form of bovine brucellosis. The rhythmic change in immunological profiles conclusively analyzed in the present investigation will help to implement control measures in Western India.

Abbreviations: PBMC: peripheral blood mononuclear cells; PCR: Polymerase chain reaction; IFN: Interferon; TNF: Tumour necrosis factor; IL: Interleukin; iNOS: Inducible nitric oxide synthase; Th: T helper

KEYWORDS:

• Brucella abortus
• cattle
• PBMC
• cytokine
• gene expression

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research received no specific grant from any funding agency in the public, commercial, or not for-profit sectors. However, the authors are grateful to the Dean, College of Veterinary and Animal Sciences, Rajasthan University of Veterinary and Animal Sciences, Bikaner, Rajasthan, India for providing necessary facilities during the period of present investigation.