TY - JOUR
T1 - Nanobody-Fc constructs targeting chemokine receptor CXCR4 potently inhibit signaling and CXCR4-mediated HIV-entry and induce antibody effector functions
AU - Bobkov, Vladimir
AU - Zarca, Aurelien M.
AU - Van Hout, Anneleen
AU - Arimont, Marta
AU - Doijen, Jordi
AU - Bialkowska, Magdalena
AU - Toffoli, Elisa
AU - Klarenbeek, Alex
AU - van der Woning, Bas
AU - van der Vliet, Hans J.
AU - Van Loy, Tom
AU - de Haard, Hans
AU - Schols, Dominique
AU - Heukers, Raimond
AU - Smit, Martine J.
PY - 2018/12
Y1 - 2018/12
N2 - Upregulation of the chemokine receptor CXCR4 contributes to the progression and metastasis of both solid and hematological malignancies, rendering this receptor an attractive therapeutic target. Besides the only FDA-approved CXCR4 antagonist Plerixafor (AMD3100), multiple other classes of CXCR4-targeting molecules are under (pre-)clinical development. Nanobodies (Nb), small single variable domains of heavy-chain only antibodies from Camelids, have appeared to be ideal antibody-fragments for targeting a broad range of epitopes and cavities within GPCRs such as CXCR4. Compared to conventional antibodies, monovalent nanobodies show fast blood clearance and no effector functions. In order to further increase their binding affinities and to restore antibody-mediated effector functions, we have constructed three different bivalent nanobody Fc-fusion molecules (Nb-Fc), targeting distinct epitopes on CXCR4, via fusion of Nbs to a Fc domain of a human IgG1 antibody. Most Nb-Fc constructs show increased binding affinity and enhanced potency in CXCL12 displacement, inhibition of CXCL12-induced signaling and CXCR4-mediated HIV entry, when compared to their monovalent Nb counterparts. Moreover, Nb-Fc induced ADCC- and CDC-mediated cell-death of CXCR4-overexpressing CCRF-CEM leukemia cells and did not affect cells expressing low levels or no CXCR4. These highly potent CXCR4 Nb-Fc constructs with Fc-mediated effector functions are attractive molecules to therapeutically target CXCR4-overexpressing tumors.
AB - Upregulation of the chemokine receptor CXCR4 contributes to the progression and metastasis of both solid and hematological malignancies, rendering this receptor an attractive therapeutic target. Besides the only FDA-approved CXCR4 antagonist Plerixafor (AMD3100), multiple other classes of CXCR4-targeting molecules are under (pre-)clinical development. Nanobodies (Nb), small single variable domains of heavy-chain only antibodies from Camelids, have appeared to be ideal antibody-fragments for targeting a broad range of epitopes and cavities within GPCRs such as CXCR4. Compared to conventional antibodies, monovalent nanobodies show fast blood clearance and no effector functions. In order to further increase their binding affinities and to restore antibody-mediated effector functions, we have constructed three different bivalent nanobody Fc-fusion molecules (Nb-Fc), targeting distinct epitopes on CXCR4, via fusion of Nbs to a Fc domain of a human IgG1 antibody. Most Nb-Fc constructs show increased binding affinity and enhanced potency in CXCL12 displacement, inhibition of CXCL12-induced signaling and CXCR4-mediated HIV entry, when compared to their monovalent Nb counterparts. Moreover, Nb-Fc induced ADCC- and CDC-mediated cell-death of CXCR4-overexpressing CCRF-CEM leukemia cells and did not affect cells expressing low levels or no CXCR4. These highly potent CXCR4 Nb-Fc constructs with Fc-mediated effector functions are attractive molecules to therapeutically target CXCR4-overexpressing tumors.
KW - Chemokine receptor
KW - CXCR4
KW - Fc domain
KW - Fc-mediated effector functions
KW - Nanobodies
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U2 - 10.1016/j.bcp.2018.10.014
DO - 10.1016/j.bcp.2018.10.014
M3 - Article
C2 - 30342023
AN - SCOPUS:85056380958
SN - 0006-2952
VL - 158
SP - 413
EP - 424
JO - Biochemical Pharmacology
JF - Biochemical Pharmacology
ER -