Isoelectric behaviour of different rabbit interferons induced by Newcastle disease virus.

Physicochemioal investigations of the last years have shown that the interferons represent a very heterogenous class of molecules. Differences are not only related to the molecular weights but also to the isoelectric behaviour. Electrofocusing demonstrated that depending on the cellular origin even interferon of one species as chick interferon 1 , interferons of mouse2, rabb i t 2 4 and human cells2 '5 show remarkable heterogeneity of electric charge. In 1969 4 we reported that the NDV induced rabbit serum interferon is not homogenous in charge. The purpose of the present paper was to