THE USE of FLOW CYTOMETRY FOR RAPID IDENTIFICATION of SALMONELLAE

Abstract

Flow cell cytometry can be used in a sensitive fluorescent immunoassay to rapidly identify salmonellae of Groups D and E. Staphylococcal Protein A couples with the Fc region of many antibodies, especially immunoglobulin G. When afluorescent marker, fluorescein isothiocyanate, is conjugated to Protein A , an antibodyantigen reaction can be visualized in a flow cell cytometer with an appropriate optical sensor afrer excitation. Ten thousand cells were individually analyzed in each cytometer run within a minute. The resultant data, presented as histograms and tables, indicated the number of cells in the suspension reacting positively with the antiserum by $uorescence, cell size, distribution and light scatter. This provides an in-depth analysis of the antibody-antigen reaction not possible with other types of immunoassays. lCorrespondence should be sent to: Dr. Millicent Goldschrnidt, Dental Branch, The University of

THE USE of FLOW CYTOMETRY FOR the RAPID CHARACTERIZATION of MONOCLONAL ANTIBODY PRODUCTION

“…Flow cell cytometry has been used to detect and characterize microorganisms using metabolite synthesis, antigen-antibody , and even DNA/RNA (Barnett et al 1984;Pinder et al 1980;Goldschmidt 1981Goldschmidt , 1985Goldschmidt , 1991Goldschmidt , 1993. The instrument was initially adapted from particle counters and automated differential blood counting machines (Valinsky 1992).…”

“…The use of fluorescent markers, some attached to antibodies, has been used to rapidly identify microorganisms (Steinkamp 1984;Monsigny ef af. 1989;Boye and Ldbner-Olesen 1990;Goldschmidt 1985Goldschmidt , 1991Goldschmidt and 1993Phillips ef af. 1987: Miller andQuarles 1990).…”