This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Moehring, T. J. Articles by Moehring, J. M. Search for Related Content PubMed PubMed Citation Articles by Moehring, T. J. Articles by Moehring, J. M.

Response of Cultured Mammalian Cells to Diphtheria Toxin IV. Isolation of KB Cells Resistant to Diphtheria Toxin

¹ Department of Medical Microbiology, The University of Vermont College of Medicine, Burlington, Vermont 05401

ABSTRACT

KB cell strains which are resistant to the lethal effects of diphtheria toxin were isolated from the toxin-sensitive KB cell line. For one such strain, KB-R2, the concentration of diphtheria toxin required to cause a 50% reduction of incorporation of amino acids into protein was more than 2,000 times that required in the sensitive KB-S cell. The KB-R2 strain was cloned by a single-cell isolation method to yield uniform strains with an even greater resistance to toxin. Resistance is a stable, inheritable property, providing a good genetic marker, and appears to be related to some alteration in the cell membrane. Preliminary studies showed that these cell strains are resistant to poliovirus and vesicular stomatitis virus as well as to toxin.