Passive hemagglutination for cytomegalovirus antibody: specificity and stability of reagents

Glutaraldehyde fixed red cells coated with CMV antigen were lyophilized in the presence of stabilizers such as glycerol, lactose, sorbitol and sucrose. These cells maintained their sensitivity for anti-CMV detection for at least 6 mth when held at 4 degrees C. Some rheumatoid factors containing sera react non-specifically with crude CMV antigen coated cells. The agglutinins in these sera could be effectively removed by adsorption with red cells coated with polymerized IgG.