Syphilis-kodecytes - novel function-spacer-lipid (FSL) modified red cells capable of sensitive and specific detection of syphilis antibodies
The ability to detect infectious agents is a prerequisite to the treatment and containment of transmittable diseases. Many diagnostics assays are based upon the detection of antibodies in serum against the infectious agent and often rely on ELISA or agglutination based assays to determine the infectious status. Using function-spacer-lipid (FSL) constructs bearing peptides (1) representative of an infectious agent attached to human red blood cells, offers a potential alternative diagnostic approach to the detection of antibody-defined infections. Using the syphilis spirochaete as a model, and a peptide selection algorithm, a series of FSL constructs were created and attached to human red cells creating syphilis-kodecytes. These kodecytes were then tested in routine blood typing platforms against serum from patients and blood donors of known syphilis status. This approach has already been successfully used to detect ethnic specific blood group antibodies (1). It was found that syphilis-kodecytes used in blood grouping platforms are capable of the same sensitivity and specificity as ELISA and Particle Agglutination assays. The ability to engineer the FSL construct and replace the functional peptide for other infectious markers allows for a highly flexible and rapid-development technique for the detection of antibodydefined infectious agent markers, and may be an important lowtechnology tool for use in epidemics and pandemics, particularly in third world environments.