The antibody response to immunization with Brucella and the levels of natural antibody to Escherichia coli and Shigella were compared in patients with systemic lupus erythematosus and control groups. After Brucella immunization, SLE patients showed a significantly lower antibody response in whole serum and in the macroglobulin antibody fraction separated by sucrose density gradient centrifugation.
John Baum, Morris Ziff