Analysis of immune complex components isolated from serum of AIDS patients

The Acquired Immune Deficiency Syndrome (AIDS) is characterized by low helper/suppressor ratios and general defects in immune function. High concentrations of immune complexes have been detected in the serum of AIDS patients. The role of immune complexes in perpetuating immune dysfunction in this disease has not been well defined. We have developed a method for detecting immune complexes by modifying the Raji cells assay for analysis on the fluorescent cell analyzer. Immune complexes from serum were bound to Raji cells and were then stained with FITC conjugated anti-human immunoglobulin. Using this method, we have analyzed immune complexes from AIDS patients, systemic lupus erythematosus patients and normal controls. When complexes in sera were analyzed for IgG and IgA, AIDS patients serum contained greater amounts of IgA than IgG. These patients contained more IgG complexes than SLE controls. Analysis of light chain isotype in the immune complexes revealed that nine in sixteen AIDS sera contained kappa light chains in greater amounts than normals, whereas lambda light chains were not present by this method of detection (16 out of 16 tested). By using this novel method, sera which have immune complexes binding to Raji cells can be identified rapidly to quantitate the amount of binding prior to elution for further qualitation.