PHAGE-DISPLAYED AND SOLUBLE MOUSE SCFV FRAGMENTS NEUTRALIZE RABIES VIRUS

A phage-display technology was used to produce a single-chain Fv antib ody fragment (scFv) from the 30AA5 hybridoma secreting anti-glycoprote in monoclonal antibody (MAb) that neutralizes rabies virus. ScFv was c onstructed and then cloned for expression as a protein fusion with the g3p minor coat protein of filamentous phage. The display of antibody fragment on the phage surface allows its selection by affinity using a n enzyme-linked immunosorbent assay (ELISA); the selected scFv fragmen t was produced in a soluble form secreted by E. coli. The DNA fragment was sequenced to define the germline gene family and the amino-acid s ubgroups of the heavy (V-H) and light (V-L) chain variable regions. Th e specificity characteristics and neutralization capacity of phage-dis played and soluble scFv fragments were found to be identical to those of the parental 30AA5 MAb directed against antigenic site II of rabies glycoprotein. Phage-display technology allows the production of new a ntibody molecule forms able to neutralize the rabies virus specificall y. The next step could be to engineer and produce multivalent and mult ispecific neutralizing antibody fragments. A cocktail of multispecific neutralizing antibodies could contain monovalent, bivalent or tetrava lent scFv fragments, for passive immunoglobulin therapy. (C) 1997 Else vier Science B.V.