A comparison of the reactivity of monoclonal and polyclonal Rh reagents with red cells after prolonged storage

Previous studies with stored red cells collected into EDTA anticoagulant had shown that commercial polyclonal anti-C, -c, and -E reagents gave acceptable reactions for 60 days, but polyclonal antie reagents reliably detected the e antigen only through 14 days. At that time it was noted that a monoclonal anti-e reacted 3+ to 4+ with red cells that no longer reacted, or reacted very weakly, with the polyclonal anti-e reagents. This observation led to a comparison study of the reactivity of monoclonal versus polyclonal Rh reagents with stored red cells. Monoclonal and polyclonal anti-C, -c, and -E reagents showed comparable reaction strengths, and gave acceptable reactions over the entire testing period. Polyclonal anti-e reagents, which are known to be of lower titer, again did not give reliable reactions with stored cells after 14 days. However, three different monoclonal anti-e reagents were able to detect the presence of the e antigen on stored cells for many weeks. This study showed that the monoclonal anti-e reagents tested are superior to polyclonal anti-e reagents for typing specimens that have been stored for more than 14 days. Immunohematology 1994;10:12.