D2B antibody and its scFvD2B fragment in nanomedicine: promising tools in the theranostics of prostate cancer

Prostate cancer (PC) is ranked the sixth deadliest cancers among men. If PC is diagnosed at metastasised stages, traditional surgery and radiation therapy have limitations. In the last few decades, antibody therapy has emerged to deliver radioactive drugs to any metastatic PC tumours; thus, improving theranostics results and prolonged patient's survival via effective targeting of prostate specific membrane antigens (PSMA). Full length anti-PSMA antibody, D2B, and its single chain variable fragment, scFvD2B, have been extensively studied as naked or combined with nanoparticles (NPs) in targeted antibody therapy. Such a combination is considered a current hotspot in research as a means to enhance the delivery, binding specificity, and stability of therapeutic or diagnostic agents. In this review, we summarise and compare data from studies published between 1993 & 2021 to highlight the major outputs from in vivo and in vitro applications of D2B and scFvD2B antibodies in PC theranostics. Special focus is set on gold nanoparticles (AuNPs) as a delivery vehicle given their unique physicochemical and biological properties. Our conclusion supports the use of AuNPs-scFvD2B conjugates in future biomedical approaches.