Induction and yield of reaginic antibodies in mouse serum and ascitic fluid.

Reaginic antibody in ascitic fluid was isolated from mice immunized with ovalbumin and TAl(OH)3 or with avalbumin and pertussis adjuvant. Partial purification of this reagin by ammonium sulphate precipitation, gel filtration, and ion-exchange column chromatography yielded a gammaglobulin fraction highly active in the passive cutaneous anaphylaxis reaction. This was identical in purity and specific activity to a fraction of partially purified reagin isolated from mouse antiserum. The recovery of reaginic activity after purification from ascitic fluid was 19 per cent compared to the 7-8 per cent recovery from anti-serum. These studies demonstrate that ascitic fluid in mice immunized with methods known to produce reaginic antibody provides an excellent source of mouse IgE.