Predicted expression of specialist and generalist traits by canine distemper virus strains in relation to different host species receptors (SLAM CD150).

Predictions designed for CDV-H proteins were tested in an in vitro fusion assay (FA) and for CDV strains tested in an in vitro virus titration assay (TA). Strong co-evolution of CDV in a homogeneous environment (domestic dog) should produce strains that express specialist traits. Weak co-evolution of CDV in heterogeneous environments (non-dog carnivores) should produce strains expressing generalist traits. The homogeneous experimental environment is Vero cells expressing domestic dog SLAM. The heterogeneous experimental environment is Vero cells expressing African lion SLAM. The last two columns summarize the experimental results from this study.