Immunohistochemical reactivity of human tissues with monoclonal antibody against Escherichia coli O104 O-specific polysaccharide containing sialic acid

Abstract

Abstract Lipopolysaccharide (LPS), the major component of outer membrane of Gram-negative bacteria contains the O-antigenic polysaccharide used for classifying bacteria into O-serotypes within species. The serotype O104 of E. coli is characterized by the presence of sialic acid in its LPS. In previous study we established the structure of its O-polysaccharide and here we report the reactivity of anti-O104 polysaccharide monoclonal antibody with human tissues. The study was conducted under an assumption that the sialic acid based molecular identity of bacterial and tissue structures is not only an understanding the mimicry based bacterial pathogenicity. Cross-reacting antibodies could be used to recognise specific human tissues depending on their histogenesis and differentiation which might be useful for diagnostic purposes. The results indicate that variety of human tissues is recognised by anti-O104 antibodies. Positive reaction has been found in the metastatic colon adenocarcinoma cells in liver, ganglioneuroma cells, ovarian endometrioid carcinoma cells, mammary invasive ductal carcinoma cells and prostate carcinoma cells. The negative reaction with monoclonal antibody anti-O104 LPS has been observed in trophoblast, cartilage, normal squamous epithelium, hematopoietic cells and certain tumours, such as squamous cell carcinoma, myxoid liposarcoma and fibrosarcoma. Further studies should determine the structure of the recognized tissue epitope.