With this bioreactor setup, VLP production can be successfully transferred from

shake flasks to a bioreactor scale (Figure 10.7). These VLPs can be either retained

in the bioreactor or continuously harvested in the harvest fraction. This depends on

the HMF and the nature of the filter used. Depending on the pore size, filter

FIGURE 10.7 (a) Daily (top) and cumulative (bottom) production of VLPs using a

perfusion-based mode of operation at bioreactor scale. (b) Adapted from [ 110]. CryoTEM

micrograph of a VLP showing the characteristic ordered ring-shaped below the cell mem-

brane. (c) Adapted from [ 110]. 3D model of a VLP rendered using electron cryotomography.

The different segmented parts of the VLP can be observed in detail, such as the individual

Gag monomers attached below the cell membrane.

Recombinant vaccines: Gag-based VLPs

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