Detection of plaque-forming cells by a latex bead technique

A new latex bead technique for measuring the plaque-forming cell (PFC) responses to bacterial antigens is described. This technique has been designed for the study of antigens that cannot be readily coated onto SRBC but may also used for antigens that adsorb onto SRBC as well. Application of the latex based technique for the study of PFC response of hamsters to Treponema reiter antigen is described in detail. Using SIII, an antigen that readily adsorbs to SRBC, we have compared the latex bead technique and the conventional SRBC-PFC technique and found that the latex bead technique is more sensitive than the conventional technique. The technique can be used for direct and indirect PFC assays. Technical details for the optimal performance of the latex bead PFC assay are outlined.