Indirect hemagglutination inhibition: a direct method for detecting cytomegalovirus antigen

We have developed a simple and sensitive technique for detecting CMV antigen in tissue culture specimens. The IHI assay is a modification of the IHA, which is capable of reliably detecting 10(3) median TCID50 of virus. With the IHI assay, antigen is detected by its capacity to inhibit the reactivity of CMV antisera of known titer in an IHA assay. The test is specific, uses readily available reagents, and is easy to perform. The IHI assay may serve as a tool for screening tissue culture specimens for CMV.