Isolation of temperature-sensitive mutants of measles virus.

Abstract

Measles virus differs from other members of paramyxoviruses in its prolonged growth cycle1), its degree of involvement of the cell nucleus2), its lack of neuraminidase3) and the sedimentability of its RNA4). We have undertaken a study of mutants of this virus in the hope that the study might circumvent some of the problems encountered with temperaturesensitive (ts) mutants of other paramyxoviruses and cast light on novel features peculiar to measles5•`7). In this paper we report the isolation of 8 ts mutants of measles virus and their biological characterization. (Portions of this work were presented at the 3rd International Congress for Virology, Spain, 19758).) Seligman and Rapp's "giant cell" strain of measles virus9) which is derived from the Edmonston isolate, was used. Vero cells10) grown as stationary monolayer cultures were employed throughout. Eagle's minimal essential medium11) added with 10% calf serum, 100 IU penicillin, 100ƒÊg streptomycin per ml and doubled vitamin concentration was used with Hanks' base for initial seeding and with Earle's salts for maintenance. Virus titrations were