previous page   Pak Vet J, 2012, 32(3): 339-344   next page
Differential Stimulatory Activities of Smooth and Rough Brucella abortus Lipopolysaccharide in Murine Macrophages
Raheela Akhtar1,2*,  Yongqun  O. He2, Charles B. Larson2, Zafar I. Chaudhary3 and Mansur ud-Din Ahmad4
1Department of Pathology, University of Veterinary and Animal Sciences, Lahore-54000, Pakistan; 2Unit of Laboratory Animal Medicine and Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109, USA; 3Faculty of Veterinary Sciences, Bhaudin Zakariya University, Multan; 4Department of Epidemiology and Public Health, University of Veterinary and Animal Sciences, Lahore-54000, Pakistan *Corresponding author:;


Brucella abortus lipopolysaccharide (LPS) was isolated and purified from rough (RB51) and smooth (S2308) strains of Brucella. The LPS preparations were used to treat murine (RAW 264.7) macrophages in order to study their differential effects.  Treated macrophages were tested by lysozyme release test (LRT), nitroblue tetrazolium test (NBT) and nitric oxide (NO) assay, respectively. Rough Brucella LPS induced significantly higher levels of lysozyme release, oxidative stress, and nitric oxide in murine macrophages than smooth Brucella LPS or combined LPS (rough + smooth LPS). These responses were dose-dependent. Macrophages treated with rough LPS were more Brucellacidal than those treated with smooth LPS. The minimal stimulation of murine macrophages by Brucella smooth LPS may provide basis for less active immune responses against smooth strains.

Key words: Brucella abortus, Cell stimulation, Lysozyme, Nitric oxide, Reactive oxygen species


ISSN 0253-8318 (Print)
ISSN 2074-7764 (Online)