Background: Human Interleukin 37 (IL37), a unique anti-inflammatory cytokine of IL1
family member, plays critical roles in innate and adaptive immunity and inflammation.
Objective: Preparation of high purity and tag-removed recombinant IL37 protein (rIL37) is critical
for its clinical application.
Method: In this study, we constructed an N-terminal cleavable GST-fused IL37 expression vector
for recombinant expression.
Results: Subsequent to transformation and optimization of the induction temperature, the soluble
expression level of rIL37 was 306.5 mg/L of culture medium at 18 °C induction in Escherichia coli.
Meanwhile, rIL37 was digested on beads by GST-HRV3C protease during GST affinity chromatography.
After further purification, the purity of rIL37 was higher than 99 %. Finally, the antiinflammatory
activity of tag-removed protein was verified by the results showing that rIL37 suppressed
IL1β production in PBMCs.
Conclusion: This work presents a protocol to produce high purity and tag-removed rIL37 with antiinflammatory
activity, which provides the firm basis for advancing clinical application in human
IL37-related inflammatory diseases.