Figure 4. Lu-Fc mutants with reduced interaction with laminin α5 still bind antibody 87207.

(A) Diagrams of Lu-Fc variants mutated at acidic residues involved in laminin α5 binding. Glu¹⁶³Asp¹⁶⁴, Glu²¹¹, and Asp²²⁹Asp²³⁰ were localized in the D2 domain, and Glu³⁴⁰, Asp³⁴¹, and Asp³⁴³ in the D3 domain. Each of these amino acids was substituted with Ala. (B) The purified mutant proteins were subjected to SDS-PAGE on a 7.5% gel under reducing conditions and stained with Coomassie Brilliant Blue. Molecular mass standards are indicated. (C) ELISA using 87207 absorbed with the mutant recombinant proteins before addition to the wells of microtiter plates coated with Sol-Lu. Each bar represents the mean of triplicate assays. Error bars indicate standard deviation.