The engineered expression of secreted HSPB5-Fc in CHO cells exhibits cytoprotection in vitro

• Main Authors: Jing Li, Jingjing Yu, Wenxian Xue, Huili Huang, Longjun Yan, Fan Sang, Shuangshuang An, Jing Zhang, Mingli Wang, Jun Zhang, Hui Li, Xiukun Cui, Jiang He, Yanzhong Hu
• Format: Article
• Language: English
• Published: BMC 2021-06-01
• Series: BMC Biotechnology
• Subjects: HSPB5; Affinity purification; Chaperone activity; polyQ; Apoptosis
• Online Access: https://doi.org/10.1186/s12896-021-00700-y

Abstract Background HSPB5 is an ATP-independent molecular chaperone that is induced by heat shock or other proteotoxic stresses. HSPB5 is cytoprotective against stress both intracellularly and extracellularly. It acts as a potential therapeutic candidate in ischemia-reperfusion and neurodegenerative diseases. Results In this paper, we constructed a recombinant plasmid that expresses and extracellularly secrets a HSPB5-Fc fusion protein (sHSPB5-Fc) at 0.42 μg/ml in CHO-K1 cells. This sHSPB5-Fc protein contains a Fc-tag at the C-terminal extension of HSPB5, facilitating protein-affinity purification. Our study shows that sHSPB5-Fc inhibits heat-induced aggregation of citrate synthase in a time and dose dependent manner in vitro. Administration of sHSPB5-Fc protects lens epithelial cells against cisplatin- or UVB-induced cell apoptosis. It also decreases GFP-Httex1-Q74 insolubility, and reduces the size and cytotoxicity of GFP-Httex1-Q74 aggregates in PC-12 cells. Conclusion This recombinant sHSPB5-Fc exhibits chaperone activity to protect cells against proteotoxicity.