CTGF knockdown in Vero cells reduces autophagy and adhesion and promotes short-term suspension adaptation

TL;DR

Reducing CTGF in Vero cells lowers autophagy and adhesion, helping them grow better in suspension, which is important for vaccine production.

Contribution

Identifies CTGF as a key regulator of autophagy and adhesion in Vero cells, enabling improved suspension culture for vaccine production.

Findings

CTGF knockdown in Vero cells reduces autophagic flux and lysosomal activity.

CTGF depletion impairs cell adhesion to extracellular matrix proteins by 50–60%.

Engineered CTGF-knockdown Vero cells maintain normal proliferation while adapting better to suspension culture.

Abstract

Vero cells are extensively used in viral vaccine production, but their adaptation to serum-free suspension culture is hindered by excessive autophagy and strong anchorage dependence.

In this study, we identified Connective Tissue Growth Factor (CTGF/CCN2) as significantly upregulated under starvation—an inducer of autophagy—via RNA-seq screening. A stable CTGF knockdown Vero cell line (knockdown efficiency >50%) was established using lentiviral shRNA.

Functional characterization demonstrated that CTGF depletion concurrently attenuated autophagic flux (evidenced by reduced LC3-II/I ratio and lysosomal activity) and impaired cell adhesion (with adhesion rates decreased by 50%–60% on extracellular matrix proteins), while maintaining normal cell proliferation.

Our findings reveal a new role for CTGF in regulating the environmental adaptation of Vero cells by coordinating autophagy and adhesion functions. The engineered cell line provides a novel strategy to overcome suspension adaptation bottlenecks, offering significant potential for improving vaccine production scalability.

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