Using the microtiter system, titration of Newcastle disease virus infectivity and neutralizing antibodies was carried out in chicken embryo fibroblasts grown in "U" or flat-bottomed plates. Infectivity was detected by a combined hemadsorption-hemagglutination method. Inhibition of that reaction indicated the presence of neutralizing antibodies. A 24-h microneutralization test was developed and ...

The antigenic properties of the VH region of immunoglobulin heavy chains were studied by means of a fragment corresponding to the variable part of the heavy chain of an IgG3 myeloma protein (KUP) and an antiserum made against this fragment. By hemagglutination, hemagglutination inhibition, and immunofluorescence techniques, it was shown that the anti-VH antiserum detected three sets of antigens...

The increased sensitivity and improved agglutination and settling patterns of formalinized sheep erythrocytes in a new buffer, HEPES (N-2-hydroxyethylpiperazine N'-2'-ethanesulfonic acid), make this system more suitable for use in the rubella hemagglutination-inhibition test.