Virus Titration

In: Science

Submitted By Fifiayo
Words 982
Pages 4
Introduction
Tissue culture, is the removal of cells from an animal or a plant, and growing the cells in a favourable artificial condition (Wiley, J.M et al, 2013). There are three types of cell culture: primary, this is cultivating the cells away from the parental tissue, secondary, which is when a primary culture is sub-cultured and cell lines, which can be continuous or finite depending on the life span of the culture. Virus titrations are used to estimate the virus concentration; it is a viral quantification technique. When detecting the virus, the cytopathic effect is looked at, whether there is lysis of the cells, vacuolation, formation of syncytia and the presence of inclusion bodies. TCID50, is the measure of the infectious titre. The end point dilution assay quantifies the amount of virus that is required to kill 50% of infected hosts or to produce a cytopathic effect in 50% of inoculated tissue culture cells (Kumar P, 2013). The purpose of the virus titration within tissue culture is to isolate and identify viruses within clinical samples, to carry out research on the viral structure, replication, genetics of the virus and the effect on the host cells, and also to prepare viruses for vaccine production.

Results
Table 1 Data used to determine the 50% endpoint using the Reed-Muench method Log of virus dilution | Infected test units | Cumulative infected (A) | Cumulative non-infected (B) | Ratio A/(A+B) | Percentage infected (%) | -1 | 5/5 | 37 | 0 | 38/38 | 100 | -2 | 5/5 | 32 | 0 | 33/33 | 100 | -3 | 5/5 | 27 | 0 | 28/28 | 100 | -4 | 5/5 | 22 | 0 | 23/23 | 100 | -5 | 5/5 | 17 | 0 | 18/18 | 100 | -6 | 4/5 | 12 | 1 | 12/13 | 92 | -7 | 3/5 | 8 | 3 | 8/11 | 72 | -8 | 2/5 | 5 | 6 | 5/11 | 45 | -9 | 2/5 | 3 | 9 | 3/12 | 25 | -10 | 2/5 | 1 | 13 | 1/14 | 7 |

Figure 1 The percentage of infected cells by the virus. As the log of virus…...

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