Fundamentals for ultrafast virus analytics

Background.

The determination of infectivity in cell culture tests usually takes five days to a week. The tests are error-prone and the result is often operator-dependent, i.e. different depending on the person performing them. These tests complicate any process development, release or general research activities in the context, e.g. development of vaccines or gene therapy vectors based on viruses. The fundamentals for a novel ultrafast method for determination of infectivity of virus will be generated. As model virus Baculovirus and Measles virus will be used.  Measles are a general vector for vaccination. Baculovirus is a vector for production of proteins in insect cells.

Aims and methods.

Three different analytical methods are being developed in parallel: (1) measurement of the Cy-toslic Ca ++ shift after infection of indicator cell lines with our model viruses (2) triggering of an "early interferon / immune response" after infection of indicator cell cells with the model viruses and (3) measurement of certain ones mRNA sequences after the model viruses have propagated in the indicator cell lines. In addition to the infectivity, the particle content must also be measured, as a bioreactor harvest contains a number of particles that are very similar to the viruses, but cannot really be separated in the following cleaning processes (the health authorities not only require the information about new vaccines Infectivity but also via the particle size distribution and the content of VLPs). With nanoparticle tracking analysis, field flow fractionation, preparative size exclusion chromatography and flow cytometry with specific antibodies against surface proteins, we will therefore conduct research on particle content measurement.

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