[Removal, detection, and limits of endotoxin in the industry of recombinant proteins]

With the advancement of synthetic biology, recombinant proteins are poised to play a significant role in medical applications. The scaled manufacturing is a pillar for the extensive application and development of recombinant proteins across various fields. In the large-scale production process of recombinant proteins, the removal and detection of endotoxins are essential to reduce their levels to safe thresholds in the final products. Currently, establishing stringent endotoxin limits for different recombinant protein products is a crucial aspect of safety assessment. This review begins by shedding light on the pathogenicity of endotoxins and discusses the methods for the removal and determination of endotoxins during the production processes of recombinant proteins. Subsequently, this review summarizes the endotoxin limits in industries such as biologics, medical devices, and human recombinant DNA products, particularly those in recombinant protein injection products. It is highlighted that regardless of whether the hosts for recombinant protein expression are bacteria or not, endotoxin testing is required for the final products of injectable recombinant proteins, and compliance with relevant industry standards is necessary. This review aims to provide a reference for the research on endotoxins in the large-scale production process of recombinant proteins.