TNF receptor II fusion protein with tandemly repeated Fc domains

Abstract

The extracellular domain of tumour necrosis factor (TNF) receptor II fused with the human IgG1 Fc region (TNFRII-Fc), as well as antibodies against TNF, has been used to treat rheumatoid arthritis. However, TNFRII-Fc is less effective than these antibodies in terms of antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) against cells bearing TNF on the cell surface. We hypothesized that these activities could be increased by fusing TNFRII with tandemly repeated Fc (TNFRII-Fc-Fc). The affinities of TNFRII-Fc-Fc for soluble TNF-α and transmembrane TNF-α and the TNF-α cytotoxicity-inhibitory activity were as potent as those of TNFRII-Fc. TNFRII-Fc-Fc showed much higher binding avidity for Fcγ receptors than TNFRII-Fc and was more potent in terms of both ADCC and CDC against cells expressing transmembrane TNF-α. TNFRII-Fc-Fc of 80 kDa, as well as TNFRII-Fc-Fc of 200 kDa, was detected. TNFRII-Fc-Fc (80 kDa) was as potent as TNFRII-Fc in terms of both ADCC and CDC. These results suggest that Fc multimerization of receptor-Fc fusion proteins can augment effector functions such as ADCC and CDC, and thereby have the potential to provide a superior therapeutic effect. This may be the case not only for TNFRII-Fc but also for other receptor-Fc fusion proteins.

Fc‐fusion proteins: new developments and future perspectives

“…The optimal ratio of Ab:Ag to use in generating ICs, and the fact that they are highly unstable, generates significant obstacles for any rational investigation. A number of approaches have been explored to engineer monomeric Fc‐fusions to improve avidity binding to APCs (Jensen et al, 2007; Nagashima et al, 2011). In one case, human serum albumin (HSA) was fused to multiple linear Fc repeats of human IgG1 (Jensen et al, 2007).…”

“…Multiple avidity has very recently been engineered into Fc‐fusions to generate both tandem Fc repeated homodimers (Nagashima et al, 2011), and star‐shaped hexameric constructs (Mekhaiel et al, 2011b), that suggest it may be possible to generate non‐immunogenic drugs that can bind up to twelve target molecules (Fig 2A). However, one of the most prominent arguments against the use of polymeric Abs, particularly in oncology applications, is that their larger size prevents penetration into tissues.…”

Fusion Proteins with Toxic Activity

“…These tandem Fc repeats increased ADCC and CDC 10-fold and threefold [89]. Duplications of the Fc region were used to increase ADCC of best-understood candidate, Enbrel 1 .…”

Plant-derived PAP proteins fused to immunoglobulin A and M Fc domains induce anti-prostate cancer immune response in mice

“…Immunoglobulin IgG1 Fc-fusion proteins have emerged as promising therapeutic drugs in immunology ( 9 ). In addition, the Fc fusion can be applied to generate dimeric and hexameric structures, likely in a star shape ( 9 , 13 - 15 ). Among diverse tissues, PAP highly exists in prostate tissues compared to other organs ( 16 ).…”