TY - JOUR
T1 - Impact of dual-baculovirus infection on the Sf9 insect cell transcriptome during rAAV production using single-cell RNA-seq
AU - Virgolini, Nikolaus
AU - Silvano, Marco
AU - Hagan, Ryan
AU - Correia, Ricardo
AU - Alves, Paula M.
AU - Clarke, Colin
AU - Roldão, António
AU - Isidro, Inês A.
N1 - Funding Information:
The authors gratefully acknowledge the funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska‐Curie grant agreement no. 813453 and from Fundação para a Ciência e a Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior (FCT/MCTES, Portugal) through national funds to iNOVA4Health (UIDB/04462/2020 and UIDP/04462/2020) and the Associate Laboratory LS4FUTURE (LA/P/0087/2020). The authors would also like to thank Généthon for kindly providing the rBAC‐GFP baculovirus, Marcos Sousa (iBET) for his support in running the bioreactors, and Siobhan Cashman and Helen Smith (both BD Biosciences) for their support on the Rhapsody platform. The graphical abstract and Figure 1a were created with BioRender.com .
Funding Information:
The authors gratefully acknowledge the funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement no. 813453 and from Fundação para a Ciência e a Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior (FCT/MCTES, Portugal) through national funds to iNOVA4Health (UIDB/04462/2020 and UIDP/04462/2020) and the Associate Laboratory LS4FUTURE (LA/P/0087/2020). The authors would also like to thank Généthon for kindly providing the rBAC-GFP baculovirus, Marcos Sousa (iBET) for his support in running the bioreactors, and Siobhan Cashman and Helen Smith (both BD Biosciences) for their support on the Rhapsody platform. The graphical abstract and Figure 1a were created with BioRender.com.
Publisher Copyright:
© 2023 iBET - Instituto de Biologia Experimental e Tecnologica and The National Institute for Bioprocessing Research and Training. Biotechnology and Bioengineering published by Wiley Periodicals LLC.
PY - 2023/9
Y1 - 2023/9
N2 - The insect cell-baculovirus expression vector system (IC-BEVS) has shown to be a powerful platform to produce complex biopharmaceutical products, such as recombinant proteins and virus-like particles. More recently, IC-BEVS has also been used as an alternative to produce recombinant adeno-associated virus (rAAV). However, little is known about the variability of insect cell populations and the potential effect of heterogeneity (e.g., stochastic infection process and differences in infection kinetics) on product titer and/or quality. In this study, transcriptomics analysis of Sf9 insect cells during the production of rAAV of serotype 2 (rAAV2) using a low multiplicity of infection, dual-baculovirus system was performed via single-cell RNA-sequencing (scRNA-seq). Before infection, the principal source of variability in Sf9 insect cells was associated with the cell cycle. Over the course of infection, an increase in transcriptional heterogeneity was detected, which was linked to the expression of baculovirus genes as well as to differences in rAAV transgenes (rep, cap and gfp) expression. Noteworthy, at 24 h post-infection, only 29.4% of cells enclosed all three necessary rAAV transgenes to produce packed rAAV2 particles, indicating limitations of the dual-baculovirus system. In addition, the trajectory analysis herein performed highlighted that biological processes such as protein folding, metabolic processes, translation, and stress response have been significantly altered upon infection. Overall, this work reports the first application of scRNA-seq to the IC-BEVS and highlights significant variations in individual cells within the population, providing insight into the rational cell and process engineering toward improved rAAV2 production in IC-BEVS.
AB - The insect cell-baculovirus expression vector system (IC-BEVS) has shown to be a powerful platform to produce complex biopharmaceutical products, such as recombinant proteins and virus-like particles. More recently, IC-BEVS has also been used as an alternative to produce recombinant adeno-associated virus (rAAV). However, little is known about the variability of insect cell populations and the potential effect of heterogeneity (e.g., stochastic infection process and differences in infection kinetics) on product titer and/or quality. In this study, transcriptomics analysis of Sf9 insect cells during the production of rAAV of serotype 2 (rAAV2) using a low multiplicity of infection, dual-baculovirus system was performed via single-cell RNA-sequencing (scRNA-seq). Before infection, the principal source of variability in Sf9 insect cells was associated with the cell cycle. Over the course of infection, an increase in transcriptional heterogeneity was detected, which was linked to the expression of baculovirus genes as well as to differences in rAAV transgenes (rep, cap and gfp) expression. Noteworthy, at 24 h post-infection, only 29.4% of cells enclosed all three necessary rAAV transgenes to produce packed rAAV2 particles, indicating limitations of the dual-baculovirus system. In addition, the trajectory analysis herein performed highlighted that biological processes such as protein folding, metabolic processes, translation, and stress response have been significantly altered upon infection. Overall, this work reports the first application of scRNA-seq to the IC-BEVS and highlights significant variations in individual cells within the population, providing insight into the rational cell and process engineering toward improved rAAV2 production in IC-BEVS.
KW - adeno-associated virus
KW - baculovirus infection
KW - BEVS
KW - biopharmaceutical production
KW - gene therapy vector
KW - RNA-seq
UR - http://www.scopus.com/inward/record.url?scp=85152079977&partnerID=8YFLogxK
U2 - 10.1002/bit.28377
DO - 10.1002/bit.28377
M3 - Article
C2 - 36919374
AN - SCOPUS:85152079977
SN - 0006-3592
VL - 120
SP - 2588
EP - 2600
JO - Biotechnology and Bioengineering
JF - Biotechnology and Bioengineering
IS - 9
ER -