IgG1-LD19.10

IgG1-LD19.10 is a **non-targeting control antibody-drug conjugate (ADC)** where a human immunoglobulin G1 (IgG1) antibody is site-specifically conjugated to the **LD19.10 linker-drug**, a novel calicheamicin-based payload. LD19.10 is engineered to eliminate the release of toxic dimethylhydrazine (DMH) catabolites associated with older calicheamicin linker drugs by using a reduction-sensitive disulfide linker rather than an acid-labile hydrazone moiety. Upon cellular uptake, reduction of the disulfide linker releases calicheamicin, inducing DNA double-strand breaks and apoptotic cell death. IgG1-LD19.10 serves as a **non-targeted control** for evaluating the specificity and systemic effects of LD19.10-conjugated ADCs in preclinical studies, particularly in solid tumor models like small cell lung cancer (SCLC)[1][3]. This construct is not meant for therapeutic use, but rather as a scientific tool for preclinical comparative analysis of ADC safety and specificity.