Half-Life Extended Nanobody-Based CD38-Specific Bispecific Killercell Engagers Induce Killing of Multiple Myeloma Cells

TY - JOUR

T1 - Half-Life Extended Nanobody-Based CD38-Specific Bispecific Killercell Engagers Induce Killing of Multiple Myeloma Cells

AU - Hambach, Julia

AU - Fumey, William

AU - Stähler, Tobias

AU - Gebhardt, Anna Josephine

AU - Adam, Gerhard

AU - Weisel, Katja

AU - Koch-Nolte, Friedrich

AU - Bannas, Peter

N1 - Copyright © 2022 Hambach, Fumey, Stähler, Gebhardt, Adam, Weisel, Koch-Nolte and Bannas.

PY - 2022

Y1 - 2022

N2 - CD38 is a target for immunotherapy of multiple myeloma. Llama-derived CD38-specific nanobodies allow easy reformatting into mono-, bi- and multispecific proteins. To evaluate the utility of nanobodies for constructing CD38-specific nanobody-based killer cell engagers (nano-BiKEs), we generated half-life extended nano-BiKEs (HLE-nano-BiKEs) by fusing a CD38-specific nanobody to a CD16-specific nanobody for binding to the Fc-receptor on NK cells and further to an albumin-specific nanobody to extend the half-life in vivo. HLE-nano-BiKEs targeting three different epitopes (E1, E2, E3) of CD38 were expressed in transiently transfected HEK-6E cells. We verified specific and simultaneous binding to CD38 on myeloma cells, CD16 on NK cells, and to albumin. We tested the capacity of these HLE-nano-BiKEs to mediate cytotoxicity against CD38-expressing multiple myeloma cell lines and primary myeloma cells from human bone marrow biopsies in bioluminescence and flowcytometry assays with NK92 cells as effector cells. The results revealed specific time- and dose-dependent cytolysis of CD38+ myeloma cell lines and effective depletion of CD38-expressing multiple myeloma cells from primary human bone marrow samples. Our results demonstrate the efficacy of CD38-specific HLE-nano-BiKEs in vitro and ex vivo, warranting further preclinical evaluation in vivo of their therapeutic potential for the treatment of multiple myeloma.

AB - CD38 is a target for immunotherapy of multiple myeloma. Llama-derived CD38-specific nanobodies allow easy reformatting into mono-, bi- and multispecific proteins. To evaluate the utility of nanobodies for constructing CD38-specific nanobody-based killer cell engagers (nano-BiKEs), we generated half-life extended nano-BiKEs (HLE-nano-BiKEs) by fusing a CD38-specific nanobody to a CD16-specific nanobody for binding to the Fc-receptor on NK cells and further to an albumin-specific nanobody to extend the half-life in vivo. HLE-nano-BiKEs targeting three different epitopes (E1, E2, E3) of CD38 were expressed in transiently transfected HEK-6E cells. We verified specific and simultaneous binding to CD38 on myeloma cells, CD16 on NK cells, and to albumin. We tested the capacity of these HLE-nano-BiKEs to mediate cytotoxicity against CD38-expressing multiple myeloma cell lines and primary myeloma cells from human bone marrow biopsies in bioluminescence and flowcytometry assays with NK92 cells as effector cells. The results revealed specific time- and dose-dependent cytolysis of CD38+ myeloma cell lines and effective depletion of CD38-expressing multiple myeloma cells from primary human bone marrow samples. Our results demonstrate the efficacy of CD38-specific HLE-nano-BiKEs in vitro and ex vivo, warranting further preclinical evaluation in vivo of their therapeutic potential for the treatment of multiple myeloma.

KW - ADP-ribosyl Cyclase 1/metabolism

KW - Albumins/therapeutic use

KW - Cell Line, Tumor

KW - Half-Life

KW - Humans

KW - Multiple Myeloma/drug therapy

KW - Single-Domain Antibodies/pharmacology

U2 - 10.3389/fimmu.2022.838406

DO - 10.3389/fimmu.2022.838406

M3 - SCORING: Journal article

C2 - 35651607

VL - 13

JO - FRONT IMMUNOL

JF - FRONT IMMUNOL

SN - 1664-3224

M1 - 838406

ER -