Engineered Lactic Acid Bacterium Lactococcus lactis Capable of Binding Antibodies and Tumor Necrosis Factor Alpha

We have optimized the display of the B domain of staphylococcal protein A on the surface of Lactococcus lactis. The maximum binding capacity was estimated at 0.146 mu g of antibody per 10(8) cells and was sustained at 86% after treatment with simulated gastric juice. A tumor necrosis factor alpha (TNF-alpha)-binding affibody was also displayed and bound TNF-alpha, which could be useful in the treatment of inflammatory bowel disease.