A Novel Anti-EGFR mAb Ame55 with Lower Toxicity and Better Efficacy than Cetuximab When Combined with Irinotecan

Figure 2

Ame55 shares different epitopes with cetuximab. (a) Ame55’s binding with EGFR could be inhibited by EGF. SA sensor surfaces were coated with Bio-rhEGFR, 100 nM antibodies were added, and 1 μM EGF was applied to inhibit the interaction. Cetuximab and hR3 were controls. (b) Interaction of Ame55 with different domains of EGFR. AHC sensor surfaces were coated with antibodies, and 200 nM recombinant proteins of EGFR truncated domains were added. (c) Competitive binding test for nimotuzumab, Ame55, and cetuximab. SA sensor surfaces were coated with first mAbs (nimotuzumab, Ame55, and cetuximab, separated in an A/B/C test), and then we loaded 200 nM his-EGFR to saturate binding; then, 500 nM of the three second antibodies were used to compete. The descent of the response means an overlapping between the epitopes of the two antibodies, whereas the elevation of the response means less overlap.

(a)

(b)

(c)