The therapeutic effect of a novel anti-TNF-α/IL-6R triple-specific fusion protein under experimental septic condition

Abstract A novel anti-TNF-α/IL-6R triple-specific fusion protein, by linking 3 single domain chains, was designed and constructed in our lab. The high purity fusion proteins were obtained by our developed prokaryotic expression system process with high binding affinity with TNF-α (94.75 pM), Human Serum Albumin (1.83 nM) and IL-6R (2.29 nM). In this study, the anti-TNF-α/IL-6R triple-specific fusion protein protected the mouse fibroblast fibrosarcoma cell line (L929) from the apoptosis effects induced by TNF-α, establishing that the expressed fusion proteins can selectively combine with TNF-α in vitro. In vivo, the survival rate of cecal ligation and puncture (CLP) was notably increased in the group with anti-TNF-α/IL-6R triple-specific fusion protein treatment, and meaningfully higher compared with the single-targeted IL-6R and TNF-α fusion protein at the same dose. After the treatment with anti-TNF-α/IL-6R triple-specific fusion protein, the level of serum TNF-α, IL-1β and IL-6 were significantly decreased, and sepsis-induced pathological injuries in the kidney were remarkably attenuated. The anti-TNF-α/IL-6R triple-specific fusion protein can be the potential candidate for the development of new drug design against sepsis.