Single-Dose Assay Technique for Variola Virus
| Autor: | Jean M. Riley, Michael D. Orlando |
|---|---|
| Rok vydání: | 1964 |
| Předmět: |
Virus suspension
Chromatography General Immunology and Microbiology Embryonated General Medicine Biology Assay technique Heart Infusion Broth Virology General Biochemistry Genetics and Molecular Biology Streptomycin medicine Bioassay Variola virus General Pharmacology Toxicology and Pharmaceutics Smallpox virus medicine.drug |
| Zdroj: | Applied Microbiology. 12:7-9 |
| ISSN: | 0003-6919 |
| DOI: | 10.1128/am.12.1.7-9.1964 |
| Popis: | A biological assay for variola virus was needed that would (i) require a minimum of time and (ii) have acceptable precision. Preliminary titrations made in 11-day-old embryonated eggs and in suckling mice (6 to 24 hr of age) demonstrated a linear relationship between the concentration of variola virus injected and the mean reciprocal time to death (MTD) of both hosts. This linear response indicated that the injection of a single dose of virus suspension and the measurement of the MTD should result in an acceptable assay method. Seven replicate samples of liquid preparations (20% chorioallantoic membrane in Heart Infusion Broth) and the freeze-dried material obtained with these suspensions were assayed in triplicate for pock infectious units and for MTD. The variance of the pock counts was far greater than was expected from a Poisson distribution, and coefficients of variation ranged from 25 to 61%. Variances obtained with the single-dilution assay were all far below that expected from a Poisson distribution, and coefficients of variations ranged from 5.2 to 13.6%. The use of the MTD assay resulted in a saving of time, a saving in the number of hosts necessary per assay, and increased precision. |
| Databáze: | OpenAIRE |
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