A method of ameliorating the symptoms of sepsis comprising directly exposing epithelial cells of a mammal in need thereof to soluble CD14, or active variants thereof. A method of obtaining CD14 from a stock solution containing protein of a mammary secretion is described. A method of directly activating B cells using a soluble polypeptide having the amino acid sequence selected from the group consisting of leu-leu-leu-leu-leu-leu-pro-ser, leu-leu-leu-leu-leu-leu-pro-leu; and leu-leu-leu-leu-leu-leu-val-his, and which is specifically recognized by the monoclonal antibody 3C10 and which activates B cells is described. Bovine CD14 genomic DNA is described.