USE OF SOLID-PHASE LIPOSOMAL IMMUNOASSAY FOR THE DETERMINATION OF BACTERIAL-ANTIGENS OF LIPOPOLYSACCHARIDE NATURE

The solid-phase liposomal immunoassay procedure for the determination of Francisella tularensis lipopolysaccharide (LPS) has been developed. This assay has been made with the use of monolayer liposomes, on the average, 360 nm in diameter with their phospholipid bilayer modified w ith F. tularensis LPS and their internal space filled with calcein use d as fluorescent marker. The assay is based on the principle of the co mpetitive immunosorbtion of liposomes and antigenic LPS on the surface of polystyrene plates sensitized with specific monoclonal antibodies. The dynamic range of the method is 50-2,500 mg/ml, the variation inde x being 2.3-11.5 %. Optimization of this method and its comparison wit h the enzyme immunoassay system for the given antigen-antibody pair ha s been made.