Fibroblast Growth Factor Inducible (Fn14)-specific Antibodies Concomitantly Display Signaling Pathway-specific Agonistic and Antagonistic Activity

Abstract

Background: Fn14 is a therapeutic target in various diseases. Results: Anti-Fn14 antibodies activate the alternative NFB pathway but not other Fn14-related activities induced by soluble or membrane-bound TWEAK. Fc␥R-bound anti-Fn14 antibodies, however, activate the full spectrum of Fn14-associated activities. Conclusion: Anti-Fn14 antibodies elicit agonistic activities differing from those of the natural Fn14 ligand TWEAK. Significance: These findings influence the rationale of designing Fn14-targeted therapies.

Modeling Hepatocellular Toxicity of Enavatuzumab, a Humanized Anti-TweakR Antibody

“…Mimicking that function with a secondary antibody dramatically increased the level of cytokines released by enavatuzumab; this finding is consistent with increased functional activity of enavatuzumab and other TNFRSF agonist antibodies when crosslinked with a secondary antibody or Protein A (Chao et al, 2013;Salzmann et al, 2013;Chuntharapai et al, 2001;White et al, 2013;Li et al, 2006;Dhein et al, 1992;Chodorge et al, 2012). However, crosslinking the antibody did not increase ALT/AST release, which was only observed when immune cells were present.…”

A novel llama antibody targeting Fn14 exhibits anti-metastatic activity in vivo

“…To further test whether 4G5, 18D1, and 5B6 can acquire agonistic activity by interaction with Fc receptors, we analyzed co-cultures of HT1080 cells and HEK293 cells transiently expressing CD16, CD32A CD32B, and CD64 and analyzed anti-Fn14 antibodyinduced IL8 production. As observed before for PDL192 and P4A8, 7 all three llama-derived antibodies acted as strong agonists in the presence of Fcγ receptor expressing cells (Fig. 3D).…”

“…Indeed, oligomerization with protein G or binding to FcγRs can achieve strong agonistic activity for various antibodies targeting members of the TNF receptor family. We have recently shown a similar behavior with P4A8 and PDL192 7 and, accordingly, all three Fn14-targeting llama antibodies displayed strong agonistic activity upon crosslinking with protein G and efficiently triggered interleukin-8 (IL8) production, cell death induction and enhancement of TNF-induced cell death ( Fig. 3A-C).…”

“…7 Especially, we showed in HT29 cells that PDL192 and P4A8 fail to stimulate the majority of Fn14-associated pathways but nevertheless nicely trigger p100 processing and NFκB inducing kinase (NIK) accumulation, two hallmarks of the alternative NFκB pathway. Thus, although P4A8 act as an inhibitor of TWEAK-induced cell death and IL8 production, it is concomitantly able to trigger the alternative pathway and thus has an activity pattern distinct from soluble and membrane TWEAK.…”

Combination of IAP antagonist and IFNγ activates novel caspase-10- and RIPK1-dependent cell death pathways

“…Active RIPK3 phosphorylates the pseudokinase MLKL, leading to its oligomerisation and MLKL-mediated membrane permeabilisation. 20 Similar to SMs, TWEAK, a TNF superfamily ligand, can synergise with TNF to kill tumour cells, [21][22][23][24] and cells that are sensitive to TWEAK-induced death are also sensitive to SMs. 24 Earlier reports demonstrated that TWEAK not only synergises with cell death ligands such as TNF, TRAIL and Fas but also with interferon-γ (IFNγ) to kill cancer cells.…”