Bordetella bronchiseptica DEEP ROUGH LPS INDUCES IL- 10 BONE MARROW DENDRITIC CELL RESPONSE

SISTI, FEDERICO; FERNANDEZ, JULIETA; MILLS, KINGSTON; HOZBOR, DANIELA

Villa Carlos Paz, Argentina

Congreso; XLIV Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2008

Though it is well known that B. bronchiseptica LPS induces aTLR4-dependent innate cytokine production, the role of thedifferent LPS portions in such induced immune response has notbeen yet elucidated. To get a better insight on this aspect weexamined cytokine production on dendritic and macrophage likecells following exposure to different purified LPS structures. Tothis end purified BMDC were exposed for 24 h to different B.bronchiseptica LPS structures (10 ng ml-1). It was observed thatboth the smooth (wild type, named LPSBb9.73) and the deep rough(derived from waaC mutant, named LPSBbLP39.) LPS inducedsimilar levels of IL-1b, TNF-a and IL-6. Only in presence of theLPSBbLP39, IL-12p40 and IL-10 were secreted in high level andthe concentration of these cytokines induced correlated with theamount of LPS employed. In parallel, murine J774 macrophageswere incubated with LPSBb9.73 or LPSBbLP39. While nosignificantly differences in IL-1b or IL-12p40 concentrations wereobserved between both LPS, TNF-a and IL-6 production wereenhanced following stimulation with LPSBb9.73 (TNF-a: 2.4±0.5ng/ml LPSBb9.73 vs. 0.1±0.03 ng/ml LPSBbLP39, IL-6: 5.2±0.2ng/ml LPSBb9.73 vs. 2.6±0.2 ng/ml LPSBbLP39). The datashowed that a LPS without the branched oligosaccharide mightinteract with TLR4 inducing a stronger anti-inflammatory responsesuggesting a regulatory role for this structure.