The Purification of Hepatitis‐Associated Antigen (HAA/SH/AU) from Human Serum and the Preparation of a Sheep Anti‐HAA Serum

HAA was obtained from a pool of HAA‐containing sera. The purification consisted of the following steps: Extraction with Freon, adsorption on and elution from Aerosil and gel filtration on a Sepharose 4B column. After purification, the presence of the HAA was demonstrated in the macro‐Ouchterlony. The purity was tested by immunoelectrophoresis and double immunodiffusion. Sheep were immunized with the purified HAA. In the macro‐Ouchterlony, the presence of anti‐HAA antibodies in the adsorbed sheep serum was demonstrated as a single precipitation line, identical with our human HAA anti‐HAA precipitation line. The anti‐HAA sheep serum was tested with good results against the HAA panel of the National Institutes of Health, Bethesda, USA.