Figure 1.
![Mechanism of action of PBD-ADCs (loncastuximab tesirine [Lonca]). (1) Lonca binds to CD19 on the tumor cell surface; (2) following internalization of Lonca, the protease-sensitive linker is cleaved and cytotoxic PBD dimers are released inside the cell; (3) the free PBD dimers bind in the minor groove of the cell DNA and form potent cytotoxic DNA cross-links in a sequence- selective fashion; (4) the cross-links result in a stalled DNA replication fork, blocking cell division; and (5) the cancer cell undergoes apoptosis.](https://ash.silverchair-cdn.com/ash/content_public/journal/blood/140/4/10.1182_blood.2021014663/3/bloodbld2021014663cf1.png?Expires=1725136305&Signature=DCpECu6dCFgBPqUPnw0hBoNv85O5vkw-o0PiTVquVnwlT5jCAkt5LvWcwZbY2ZDeGT8wUAHrdNLkfAVLMJISESZUNNXyyejQ19F-2UH7JMD9EFCYJ6jQg8Zw86hVXH-lKvHX9vgHPyDgZ3Jwvk5A3rijsDxsPILgOtGVHH~m1C9DWzPCK2R3ea8Sk8zBM5izQaBBMPLv-ROCH1X-R8l5~AlhZWbfCCD~VQaDTsOd7i24QrwR1v7QycC7m05LceqRUlRb-fWzWN9GwTLCPU73NGzdaw-x1Qp3VVSRuPy6kRKJw4TaQdHrKIRZCAbrd~cqEhQI0c~EUwhwuRRDuoJQDA__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Mechanism of action of PBD-ADCs (loncastuximab tesirine [Lonca]). (1) Lonca binds to CD19 on the tumor cell surface; (2) following internalization of Lonca, the protease-sensitive linker is cleaved and cytotoxic PBD dimers are released inside the cell; (3) the free PBD dimers bind in the minor groove of the cell DNA and form potent cytotoxic DNA cross-links in a sequence- selective fashion; (4) the cross-links result in a stalled DNA replication fork, blocking cell division; and (5) the cancer cell undergoes apoptosis.