EXTREMELY HIGH-TITER POLYCLONAL ANTISERA AGAINST SMALL NEUROTRANSMITTER MOLECULES - RAPID PRODUCTION, CHARACTERIZATION AND USE IN LIGHT-MICROSCOPIC AND ELECTRON-MICROSCOPIC IMMUNOCYTOCHEMISTRY

We have produced polyclonal antibodies against the small amino acid ne urotransmitters, GABA, glutamate, glycine and taurine, with a simple n ew technique using antigens co-adsorbed with an adjuvant peptide to go ld particles, which causes rapid and massive immune responses in all a nimals that we have studied. These antibodies are all of extremely hig h titre; they are typically used in immunocytochemistry at dilutions f rom 1 in 250 000 to 1 in 1 000 000 which represents an increase in tit re of at least two orders of magnitude compared to standard antibody p roduction techniques. Such very high dilutions result in minimal backg round labeling and a high signal-to-noise ratio when applied to sectio ns of aldehyde-fixed, epoxy resin-embedded tissues at both light- and electron-microscopic levels. Each antibody displays minimal cross-reac tivity with other neurotransmitter molecules. We suggest that our tech nique may be broadly applicable for raising antibodies against a wide variety of antigens of interest to neuroscientists, particularly those that normally elicit weak immune responses. The technique may also as sist in clonal expansion prior to generation of monoclonal antibodies and may be viable, with modifications, for use in human immunisations.