Purification of Nerve Growth Factor Antibodies by Affinity Chromatography

Pure antibodies to nerve growth factor have been isolated from sheep nerve growth factorantiserum by affinity chromatography using 2.5 S nerve growth factor linked to Sepharose 4B by means of cyanogen bromide. The elution of the antibodies was accomplished either at low pH (pH 2) or by high salt concentration (4.5 wMgC12). The purity of the antibodies was established by SDS‐gel electrophoresis. Their immunological activity was tested by imrnunoprecipitation and their biological activity in a tissue culture assay using embryonic chick dorsal root ganglia.