Detection of immunoglobulin M antibody to Epstein-Barr virus by use of an enzyme-labeled antigen.

Immunoglobulin M (IgM) antibodies to Epstein-Barr virus were detected by using microtiter plates coated with anti-mu-chain antiserum and enzyme-labeled Epstein-Barr virus antigen. Optimum conditions for labeling were determined. The addition of unlabeled control antigen to the enzyme-labeled antigen was effective in reducing background reactions. Rheumatoid factor no longer interfered. Blocking of specific IgM antibody by IgG also was no longer observed. Four different methods for the detection of acute Epstein-Barr virus infections were compared. A combination of the enzyme-labeled antigen-IgM test with the detection of antibodies to either Epstein-Barr nuclear antigen or heterophile antigen was highly sensitive and specific. By changing the solid phase, IgA antibodies to Epstein-Barr virus could be detected.