HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

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 Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Halstead, S. B. Articles by Putvatana, R. Search for Related Content PubMed PubMed Citation Articles by Halstead, S. B. Articles by Putvatana, R.

Selection of Attenuated Dengue 4 Viruses by Serial Passage in Primary Kidney Cells

II. Attributes of Virus Cloned at Different Dog Kidney Passage Levels

Scott B. Halstead^*, Nyven J. Marchette^*, Arwin R. Diwan^*, Nicholas E. Palumbo AND Ravithat Putvatana^*

^* Department of Tropical Medicine and Medical Microbiology, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii 96816
Department of Comparative Medicine, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii 96822

Uncloned dengue (DEN) 4 (H-241) which had been passaged 15, 30 and 50 times in primary dog kidney (PDK) cells were subjected to two successive terminal dilution procedures. In the first (3Cl), virus was diluted in 10-fold steps in 10 replicate tubes. An infected tube from a dilution row with three or fewer virus-infected tubes was selected for two further passages. In the second (TD3), virus was triple terminal diluted using 2-fold dilution steps and selecting one positive tube out of 10. Both procedures selected virus population which differed from antecedents. Plaque size of PDK 15 was medium, PDK 30, small and PDK 50, pin-point. PDK 19-3Cl and 34-3Cl were medium and 56-3Cl, 24-TD3, 35-TD3 and 61-TD3 were all small. All cloned virus replication was completely shut-off at 38.5°C; PDK 15 and 30 continued to replicate at this temperature. Uncloned viruses showed a graduated decrease in monkey virulence with PDK passage; cloned viruses were either avirulent for monkeys (19-3Cl, 56-3Cl, 24-TD3 and 35-TD3) or produced revertant large plaque parental-type viremia (35-3Cl and 61-TD3). Those cloned viruses which exhibited temperature sensitivity, reduced monkey virulence and stability after monkey passage may be suitable as vaccine candidates for evaluation in human beings.

Accepted for publication January 6, 1984.