The Effect of Overall Charge and pH upon the Preparation of Anti Basement Antibodies and upon Their Capacity of Binding in Bullous PemphigoidSummary. 1. By precipitation with ethacridine lactate-ammonium sulfate a preparation from a bullous pemphigoid serum is obtained and separated by means of chromatography on ion exchanger employing various ranges of pH.2. The anti basement antibodies are associated by far with the negative fraction of Ig G.3. With a acid ion exchanger the antibodies are in the second fraction for the most part and with a basic one they are in the first fraction totally.4. Binding the antibodies to antigen is observed over the whole range of pH pertaining a maximum of degree at 8.5.5. Antinuelear antibodies are observed too which react at low degrees of pH.