Reaginic antibody production to protein antigens of Escherichia coli and Pseudomonas aeruginosa by mice.

Water-soluble antigens isolated from acetone-dried, gram-negative bacteria elicited reaginic antibody formation in mice. Antibodies specific for Escherichia coli antigens reacted with antigens isolated from several enterobacterial species tested, but not with antigens isolated from Pseudomonas aeruginosa. Reaginic antibodies induced by antigens isolated from a P. aeruginosa strain reacted with antigens isolated from several P.aeruginosa serotypes as well as with a purified protein component of the envelope of P. aeruginosa. The anti-Pseudomonas reagins did not cross-react with enterobacterial antigens. Antigenicity of the bacterial extracts was destroyed by trypsin treatment and reduced by heating, which suggested that the antigens were protein in nature. Whole bacterial cells adsorbed out reaginic antibodies, indicating that the antigens are located at or near the surface of the bacteria.