OFF7-ETA

OFF7-ETA is a recombinant fusion toxin composed of a Designed Ankyrin Repeat Protein (DARPin) termed OFF7, which is engineered for high-affinity binding to a specific (but unspecified in published literature) cell surface target, fused to an ETA (exotoxin A) fragment derived from Pseudomonas aeruginosa. The ETA fragment in such fusion toxins is truncated (ETA″) to remove the native cell-binding domain, retaining the catalytic domain that inhibits protein synthesis via ADP-ribosylation of elongation factor 2, leading to cell death. OFF7-ETA was developed as a control agent in parallel to targeted DARPin-fusion toxins such as Ec4-ETA″, which target EpCAM on carcinoma cells. OFF7-ETA does not specifically recognize EpCAM and is used as an irrelevant or negative control in preclinical studies on tumor-targeted toxin therapies. Its antitumor activity is therefore presumed limited to cells expressing the OFF7 target, but it is typically used to demonstrate the specificity and efficacy of targeted constructs in both in vitro cytotoxicity and in vivo tumor accumulation models.[5]

Other names

OFF7-ETAOFF-7-ETAOFF 7-ETA