Citation
- Authors: Barbieri E. et al.
- Year: 2023
- Journal: Biotechnol Bioeng 1–22
- Applications: in vitro / DNA / PEIpro
- Cell type: HEK-293T
Description: Human embryonic kidney Fibroblast
Known as: HEK293T, 293T
Abstract
The recent uptick in the approval of ex vivo cell therapies highlights the relevance of
lentivirus (LV) as an enabling viral vector of modern medicine. As labile biologics,
however, LVs pose critical challenges to industrial biomanufacturing. In particular, LV
purification—currently reliant on filtration and anion‐exchange or size‐exclusion
chromatography—suffers from long process times and low yield of transducing
particles, which translate into high waiting time and cost to patients. Seeking to
improve LV downstream processing, this study introduces peptides targeting the
enveloped protein Vesicular stomatitis virus G (VSV‐G) to serve as affinity ligands for
the chromatographic purification of LV particles. An ensemble of candidate ligands
was initially discovered by implementing a dual‐fluorescence screening technology
and a targeted in silico approach designed to identify sequences with high selectivity
and tunable affinity. The selected peptides were conjugated on Poros resin and their
LV binding‐and‐release performance was optimized by adjusting the flow rate,
composition, and pH of the chromatographic buffers. Ligands GKEAAFAA and
SRAFVGDADRD were selected for their high product yield (50%–60% of viral
genomes; 40%–50% of HT1080 cell‐transducing particles) upon elution in PIPES
buffer with 0.65 M NaCl at pH 7.4. The peptide‐based adsorbents also presented
remarkable values of binding capacity (up to 3·109 TU per mL of resin, or 5·1011 vp
per mL of resin, at the residence time of 1 min) and clearance of host cell proteins
(up to a 220‐fold reduction of HEK293 HCPs). Additionally, GKEAAFAA
demonstrated high resistance to caustic cleaning‐in‐place (0.5 M NaOH, 30 min)
with no observable loss in product yield and quality