Burkholderia pseudomallei lipopolysaccharide cause differential stimulations of innate immune response in murine macrophages

Abstract

Lipopolysaccharide (LPS) of Burkholderia pseudomallei is known to be involved in innate immune response. B. pseudomallei expresses one of four LPS types: A, B, B2, or rough, all of which can be found in near-neighbor species. Nitric oxide (NO) and cytokines produced by murine macrophages were used to determine the immunogenicity of the different LPS types from B. pseudomallei and select near neighbor species. We found that type A LPS from B. pseudomallei 1026b produced a weaker immune response compared to type B and B2 LPS from B. pseudomallei MB296 and MB840, respectively, as well as compared to all the near neighbor strains. However, the gene expression levels of TLR2 and TLR4 do not relate to the results obtained from NO and cytokine experiments. There were no differences in the levels of TLR gene expression when comparing between the various LPS types. These results suggest that B. pseudomallei types B and B2 LPS are more immunogenic than B. pseudomallei type A LPS when it comes to NO and cytokine production and not with TLR gene expression