Journal: mAbs

Article Title: Beyond bispecificity: Controlled Fab arm exchange for the generation of antibodies with multiple specificities

doi: 10.1080/19420862.2021.2018960

Figure Lengend Snippet: Generation of multispecific DB-VHH constructs. Trastuzumab IgG1-K409R mAb (anti-HER2) C-termini are fused to VHHs directed against EGFR, IL6R or NKG2D via a GS-linker. CS06 IgG1-F405L mAb (anti-c-MET) is fused to the same VHH molecules in the same manner. After recombinant production and purification, parental IgG-VHHs are recombined pairwise by reduction and reoxidation. The matching K409R and F405L mutations drive the generation of heterodimeric multispecific DB-VHHs.

Article Snippet: The biosensors were then rinsed in kinetics buffer (KB; PBS + 0.1% Tween-20 + 1% bovine serum albumin (BSA)) for 45 s (baseline) and the corresponding antigen was associated to the biosensor for 300 s. Different antigen concentrations (1:2 dilution rows in KB) were tested in order to identify the dynamic range of the binding kinetics and the most suitable concentration ranges were determined as follows: HER2/ErbB2 ECD-His Tag (Sino Biological, Cat: 10004- H08H) – 0.78 nM to 50 nM, c-MET ECD-strepII-His Tag (in-house production) – 0.39 nM to 25 nM, human EGFR-His Tag (ACRO Biosystems, Cat: EGR-H5222) – 1.5 nM to 100 nM, human IL6R ECD-His Tag (Sino Biological, Cat: 10398-H08H) – 0.78 nM to 50 nM, and human NKG2D-His Tag (Sino Biological, Cat: 10575-H07B) – 0.78 nM to 50 nM.

Techniques: Construct, Recombinant, Purification

Journal: mAbs

Article Title: Beyond bispecificity: Controlled Fab arm exchange for the generation of antibodies with multiple specificities

doi: 10.1080/19420862.2021.2018960

Figure Lengend Snippet: Binding affinities measured for each paratope using recombinant antigens

Article Snippet: The biosensors were then rinsed in kinetics buffer (KB; PBS + 0.1% Tween-20 + 1% bovine serum albumin (BSA)) for 45 s (baseline) and the corresponding antigen was associated to the biosensor for 300 s. Different antigen concentrations (1:2 dilution rows in KB) were tested in order to identify the dynamic range of the binding kinetics and the most suitable concentration ranges were determined as follows: HER2/ErbB2 ECD-His Tag (Sino Biological, Cat: 10004- H08H) – 0.78 nM to 50 nM, c-MET ECD-strepII-His Tag (in-house production) – 0.39 nM to 25 nM, human EGFR-His Tag (ACRO Biosystems, Cat: EGR-H5222) – 1.5 nM to 100 nM, human IL6R ECD-His Tag (Sino Biological, Cat: 10398-H08H) – 0.78 nM to 50 nM, and human NKG2D-His Tag (Sino Biological, Cat: 10575-H07B) – 0.78 nM to 50 nM.

Techniques: Binding Assay, Recombinant, Construct

Journal: mAbs

Article Title: Beyond bispecificity: Controlled Fab arm exchange for the generation of antibodies with multiple specificities

doi: 10.1080/19420862.2021.2018960

Figure Lengend Snippet: Biolayer interferometry analysis of simultaneous antigen binding of tri- and tetraspecific DB-VHHs. (a), (b) and (c) show exemplary sensorgrams for trispecific molecules and (d) a tetraspecific DB-VHH. The first association step represents binding of the DB-VHH (200 nM) via its CS06 paratope to biotinylated c-MET immobilized to streptavidin biosensors. Second (and third for (D)) association step is performed using an IL6R, EGFR or NKG2D recombinant protein (200 nM). The last association step is performed using HER2 (200 nM). Kinetic buffer (KB) controls were applied as negative controls for each association step.

Article Snippet: The biosensors were then rinsed in kinetics buffer (KB; PBS + 0.1% Tween-20 + 1% bovine serum albumin (BSA)) for 45 s (baseline) and the corresponding antigen was associated to the biosensor for 300 s. Different antigen concentrations (1:2 dilution rows in KB) were tested in order to identify the dynamic range of the binding kinetics and the most suitable concentration ranges were determined as follows: HER2/ErbB2 ECD-His Tag (Sino Biological, Cat: 10004- H08H) – 0.78 nM to 50 nM, c-MET ECD-strepII-His Tag (in-house production) – 0.39 nM to 25 nM, human EGFR-His Tag (ACRO Biosystems, Cat: EGR-H5222) – 1.5 nM to 100 nM, human IL6R ECD-His Tag (Sino Biological, Cat: 10398-H08H) – 0.78 nM to 50 nM, and human NKG2D-His Tag (Sino Biological, Cat: 10575-H07B) – 0.78 nM to 50 nM.

Techniques: Binding Assay, Recombinant

Journal: mAbs

Article Title: Beyond bispecificity: Controlled Fab arm exchange for the generation of antibodies with multiple specificities

doi: 10.1080/19420862.2021.2018960

Figure Lengend Snippet: Specific cell clustering due to simultaneous binding of the DB-VHHs to three different cancer cell lines. Flow cytometry cytograms represent the fluorescence signals of the different cell populations. (a) Cells without antibody construct. Upper left gate = HCC-1954 (HER2 +++ ) cells stained with DeepRed, lower left gate = MDA-MB-468 (EGFR +++ ) cells stained with CMRA, lower right gate = EBC-1 (c-MET ++ ) cells stained with CFSE, upper right gate = HCC-1954 + EBC-1 cell doublets. Events in all three fluorescence channels (cell triplets) were marked in red. Cells were incubated in the presence of 1 nM (b) bispecific DB, (c) and (d) trispecific DB-VHHs, (e) and (f) tetraspecific DB-VHHs.

Article Snippet: The biosensors were then rinsed in kinetics buffer (KB; PBS + 0.1% Tween-20 + 1% bovine serum albumin (BSA)) for 45 s (baseline) and the corresponding antigen was associated to the biosensor for 300 s. Different antigen concentrations (1:2 dilution rows in KB) were tested in order to identify the dynamic range of the binding kinetics and the most suitable concentration ranges were determined as follows: HER2/ErbB2 ECD-His Tag (Sino Biological, Cat: 10004- H08H) – 0.78 nM to 50 nM, c-MET ECD-strepII-His Tag (in-house production) – 0.39 nM to 25 nM, human EGFR-His Tag (ACRO Biosystems, Cat: EGR-H5222) – 1.5 nM to 100 nM, human IL6R ECD-His Tag (Sino Biological, Cat: 10398-H08H) – 0.78 nM to 50 nM, and human NKG2D-His Tag (Sino Biological, Cat: 10575-H07B) – 0.78 nM to 50 nM.

Techniques: Binding Assay, Flow Cytometry, Fluorescence, Construct, Staining, Incubation

Journal: mAbs

Article Title: Beyond bispecificity: Controlled Fab arm exchange for the generation of antibodies with multiple specificities

doi: 10.1080/19420862.2021.2018960

Figure Lengend Snippet: Simultaneous interaction of the DB-VHHs with HCC-1954 and EBC-1 target cells and binding of recombinant IL6R. Flow cytometry cytograms represent the fluorescence signals of the two cell populations and bound recombinant IL6R, detected with an anti-His6 detection antibody. (a) Cells without antibody construct. Upper left gate = HCC-1954 (HER2+++) cells stained with DeepRed, lower right gate = EBC-1 (c-MET++) cells stained with CFSE, upper right gate = HCC-1954 + EBC-1 cell doublets. Events in all three fluorescence channels (HCC-1954 + EBC-1 + bound recombinant IL6R-His Tag) were marked in blue. Cells were incubated in the presence of 10 nM (b) bispecific DB, (c) and (d) trispecific DB-VHHs, (e) and (f) tetraspecific DB-VHHs.

Article Snippet: The biosensors were then rinsed in kinetics buffer (KB; PBS + 0.1% Tween-20 + 1% bovine serum albumin (BSA)) for 45 s (baseline) and the corresponding antigen was associated to the biosensor for 300 s. Different antigen concentrations (1:2 dilution rows in KB) were tested in order to identify the dynamic range of the binding kinetics and the most suitable concentration ranges were determined as follows: HER2/ErbB2 ECD-His Tag (Sino Biological, Cat: 10004- H08H) – 0.78 nM to 50 nM, c-MET ECD-strepII-His Tag (in-house production) – 0.39 nM to 25 nM, human EGFR-His Tag (ACRO Biosystems, Cat: EGR-H5222) – 1.5 nM to 100 nM, human IL6R ECD-His Tag (Sino Biological, Cat: 10398-H08H) – 0.78 nM to 50 nM, and human NKG2D-His Tag (Sino Biological, Cat: 10575-H07B) – 0.78 nM to 50 nM.

Techniques: Binding Assay, Recombinant, Flow Cytometry, Fluorescence, Construct, Staining, Incubation

Journal: mAbs

Article Title: Beyond bispecificity: Controlled Fab arm exchange for the generation of antibodies with multiple specificities

doi: 10.1080/19420862.2021.2018960

Figure Lengend Snippet: DB-VHHs elicit potent and specific NK cell-mediated target cell killing. Tumor cells were incubated with primary effector cells (NK cells) at a 1:5 ratio in the presence of antibody constructs in different concentrations. Error bars represent standard deviation of two biological replicates. Wildtype CS06 and trastuzumab with active Fc effector functioning were used as an ADCC reference (green). (a) and (b): c-MET-positive EBC-1 target cells, (c) and (d) HER2-overexpressing SK-BR-3 target cells. (a) and (c): NK cell cytotoxicity triggered by parental antibodies. (b) and (d): DB-VHHs serve as NK cell engager and mediate tumor cell killing.

Article Snippet: The biosensors were then rinsed in kinetics buffer (KB; PBS + 0.1% Tween-20 + 1% bovine serum albumin (BSA)) for 45 s (baseline) and the corresponding antigen was associated to the biosensor for 300 s. Different antigen concentrations (1:2 dilution rows in KB) were tested in order to identify the dynamic range of the binding kinetics and the most suitable concentration ranges were determined as follows: HER2/ErbB2 ECD-His Tag (Sino Biological, Cat: 10004- H08H) – 0.78 nM to 50 nM, c-MET ECD-strepII-His Tag (in-house production) – 0.39 nM to 25 nM, human EGFR-His Tag (ACRO Biosystems, Cat: EGR-H5222) – 1.5 nM to 100 nM, human IL6R ECD-His Tag (Sino Biological, Cat: 10398-H08H) – 0.78 nM to 50 nM, and human NKG2D-His Tag (Sino Biological, Cat: 10575-H07B) – 0.78 nM to 50 nM.

Techniques: Incubation, Construct, Standard Deviation

Journal: mAbs

Article Title: Beyond bispecificity: Controlled Fab arm exchange for the generation of antibodies with multiple specificities

doi: 10.1080/19420862.2021.2018960

Figure Lengend Snippet:

Article Snippet: The biosensors were then rinsed in kinetics buffer (KB; PBS + 0.1% Tween-20 + 1% bovine serum albumin (BSA)) for 45 s (baseline) and the corresponding antigen was associated to the biosensor for 300 s. Different antigen concentrations (1:2 dilution rows in KB) were tested in order to identify the dynamic range of the binding kinetics and the most suitable concentration ranges were determined as follows: HER2/ErbB2 ECD-His Tag (Sino Biological, Cat: 10004- H08H) – 0.78 nM to 50 nM, c-MET ECD-strepII-His Tag (in-house production) – 0.39 nM to 25 nM, human EGFR-His Tag (ACRO Biosystems, Cat: EGR-H5222) – 1.5 nM to 100 nM, human IL6R ECD-His Tag (Sino Biological, Cat: 10398-H08H) – 0.78 nM to 50 nM, and human NKG2D-His Tag (Sino Biological, Cat: 10575-H07B) – 0.78 nM to 50 nM.

Techniques: Variant Assay, Hydrophobic Interaction Chromatography, Mutagenesis, Molecular Weight, High Performance Liquid Chromatography