10 Recombinant vaccines:
Gag-based VLPs
Laura Cervera, Irene González-Domínguez,
Jesús Lavado-García, and Francesc Gòdia
Grup d’Enginyeria Cel·lular i Bioprocés, Universitat
Autònoma de Barcelona, Bellaterra, Barcelona, Spain
CONTENTS
10.1
Virus-Like Particles....................................................................................239
10.2
HIV-1 Gag VLPs .......................................................................................241
10.3
Production of HIV-1 Gag VLPs................................................................245
10.3.1 PEI-Mediated Transient Transfection..........................................245
10.4
Methods to Improve the Production Process ............................................247
10.4.1 Serum-Free Media........................................................................247
10.4.2 Cell Lines/Plasmids......................................................................248
10.4.3 Optimization of TGE ...................................................................248
10.4.4 Additives to Increase Transient Transfection and Protein
Production.....................................................................................248
10.4.5 Cell Culture Modes......................................................................249
10.5
Examples of Gag-Based VLPs ..................................................................256
10.6
Scalable DSP for HIV-1 Gag VLPs..........................................................256
10.7
Characterization and Quantification of VLPs ...........................................258
References..............................................................................................................259
10.1
VIRUS-LIKE PARTICLES
Virus-like particles (VLPs) resemble the viral native conformation by the re-
combinant expression of their structural proteins. Their highly organized and re-
petitive structure has proven that they generate a potent immunogenic response
activating both cellular and humoral immunogenicity responses [1,2]. VLPs can be
classified in non-enveloped and enveloped structures (Figure 10.1). Within this
general classification, there is a large diversity of VLP configurations: from the
simplest non-enveloped single-protein structure, such as in the Hepatitis B, to
multilayered protein configurations [3]. Enveloped VLPs consist of one or more
structural protein surrounded by the producer cell membrane that is acquired when
the VLP buds from the cell. If there are antigens expressed at the producer cell
membrane, when it buds, they are incorporated at the surface of the VLP. The ease
of production, safety, and their efficient recognition and cellular uptake, has ex-
panded the interest on the possible applications of these structures in the last
DOI: 10.1201/9781003229797-10
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