Activation of innate immunity by a capsular saccharide from B. fragilis

CARB 114

Cecilia H. Marzabadi, marzabce@shu.edu, Department of Chemistry and Biochemistry, Seton Hall University, 400 South Orange Avenue, South Orange, NJ 07079 and Dennis L. Kasper, Channing Laboratory, Department of Medicine, and Department of Microbiology and Molecular Genetics, Brigham and Women's Hospital, Harvard Medical School, 181 Longwood Ave, Boston, MA 02115.
Bacteriodes fragilis is a commensal, Gram-negative, anaerobic bacterium that resides in the mammalian gut. The capsular saccharides of B. fragilis possess unique zwitterionic structures which have been shown to be responsible for their immunological properties. One of these saccharides, polysaccharide A (PSA), has been demonstrated to stimulate T-cell differentiation in mammals via iNOS expression, MHCII presentation, co-stimulation and cytokine production. These immunological events have been linked to activation of Toll-like receptors (TLRs) in other systems. We report our investigations into the role of TLRs and other effector molecules in the activation of antigen presenting cells by PSA. Possible mechanisms used by this saccharide to link innate and cellular immunity in mammals will be discussed.
 

Carbohydrate Chemistry and Biochemistry
8:30 AM-11:50 AM, Thursday, August 23, 2007 BCEC -- 162B, Oral

Division of Carbohydrate Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007