Behavior of a Cloned Murine Interferon α/β Receptor Expressed in Homospecific or Heterospecific Background

A murine interferon (IFN) α/β receptor was cloned from the IFN-sensitive L1210 cell line on the basis of its homology with the human receptor. A combination of methods that includes the screening of random-primed and oligo(dT)-primed cDNA libraries and polymerase chain reactions with a single-side specificity was used. At the amino acid level, the murine IFN-α/β shows 46% identity with its human counterpart. Both human WISH cells presenting a low sensitivity to mouse IFN and a murine L1210 mutant subline that does not express the receptor have been stably transfected with the murine IFN-α/β receptor. Whereas transfected human cells became sensitive to a limited number of mouse IFN-α/β subtypes, the transfected murine L1210 mutant was found to be fully complemented and became sensitive to all mouse IFN-α/β subtypes tested, including those that were not active on transfected human cells. These results strongly suggest that the receptor described here is implicated in the mediation of the activities of all murine IFN-α/β subtypes.