Cross-species and intraspecies reactivities of monoclonal antibodies against choline acetyltransferase.

We have previously reported the first successful production of monoclonal antibodies against the cholinergic neuronal marker, choline acetyltransferase (ChAT). We now report some inter-and intraspecies cross-reactivity studies of the monoclonal antibody AB1. This antibody reacted most strongly with bovine ChAT and weakly with sheep and human enzyme. Similar amounts of binding were observed with the two forms of bovine ChAT separated by ion exchange chromatography. The antibody also reacted equally well with human ChAT derived from either brain or placenta.