Abstract: A method of increasing the percentage of mouse and human Tregs is provided comprising providing B.fragilis or PSA and vitamin D or vitamin D metabolite to said mouse or human. Also, a method for treating inflammatory bowel diseases in an individual is presented where the individual is given a combination of vitamin D and B. fragilis or PSA. Such a treatment may be particularly effective in individuals who are either Vitamin D insufficient or deficient.

Abstract: Certain zwitterionic polysaccharides, including those naturally expressed by commensal B. fragilis in the gut, interact with cells of the immune system and affect the TH1/TH2 balance so as to promote health. Nutritional formulas and nutritional supplements containing isolated preparations of such zwitterionic polysaccharides, and methods for preparing the nutritional formulas and supplements, are provided. Also provided is a method of promoting immune system maturation in an infant involving enteral administration of a nutritional formula or nutritional supplement of the invention.

Abstract: Provided is a method and a composition for improving behavioral performance in an individual comprising identifying an individual in need of treatment, and providing such an individual a composition comprising bacteria within the genus Bacteroides.

Abstract: Antigen specific regulatory T cells are described and related compositions, methods and systems. Methods to generate an antigen specific anti-inflammatory regulatory T cell is provided, the method comprising contacting either a T cell or an antigen presenting cell with a zwitterionic polysaccharide conjugated to the antigen for a time and under condition to generate an antigen specific regulatory T cell that is capable of inhibiting a pro-inflammatory response against the antigen.

Abstract: PSA is delivered to the host by outer membrane vesicles (OMVs), secretion structures that target bacterial molecules to host cells. Purified OMVs direct the in vitro differentiation of functional Tregs with potent suppressive activity in a PSA dependent manner. Treatment of animals with OMVs containing PSA prevents experimental colitis and suppresses pro-inflammatory cytokine responses in the gut, and indicate that compositions, medicaments, and methods useful for the treatment of inflammation, and more particularly, inflammatory bowel diseases.

Abstract: A method and system is presented for screening bacteria, products purified or made by bacteria and/or other bacterial substance for anti-inflammatory ability.

Abstract: Certain zwitterionic polysaccharides, including those naturally expressed by commensal B. fragilis in the gut, interact with cells of the immune system and affect the TH1/TH2 balance so as to promote health. Nutritional formulas and nutritional supplements containing isolated preparations of such zwitterionic polysaccharides, and methods for preparing the nutritional formulas and supplements, are provided. Also provided is a method of promoting immune system maturation in an infant involving enteral administration of a nutritional formula or nutritional supplement of the invention.

Abstract: The present invention is a substantially purified sortase-transamidase enzyme from Gram-positive bacteria, such as Staphylococcus aureus. A specific sortase-transamidase enzyme disclosed has a molecular weight of about 29,076 daltons and catalyzes a reaction that covalently cross-links the carboxyl terminus of a protein having a sorting signal to the peptidoglycan of a Gram-positive bacterium, where the sorting signal has a a motif of NPQ/KTN/G therein. Variants of the enzyme, methods for cloning the gene encoding the enzyme and expressing the cloned gene, and methods of use of the enzyme, including for screening for antibiotics and for display of proteins or peptides on the surfaces of Gram-positive bacteria, are also disclosed.

Abstract: The present invention is a substantially purified sortase-transamidase enzyme from Gram-positive bacteria, such as Staphylococcus aureus. A specific sortase-transamidase enzyme disclosed has a molecular weight of about 29,076 daltons and catalyzes a reaction that covalently cross-links the carboxyl terminus of a protein having a sorting signal to the peptidoglycan of a Gram-positive bacterium, where the sorting signal has a a motif of NPQ/KTN/G therein. Variants of the enzyme, methods for cloning the gene encoding the enzyme and expressing the cloned gene, and methods of use of the enzyme, including for screening for antibiotics and for display of proteins or peptides on the surfaces of Gram-positive bacteria, are also disclosed.