Detection of HuCAL derived
Since HuCAL derived antibodies are human Fab molecules, they can be detected by antisera developed against human IgG F(ab’)2 preparations. In addition, HuCAL antibodies are usually equipped with one or two tags (genetically fused to the C-terminus of the antibody heavy chain), and can be detected by using commercially available anti-tag antibodies. We recommend the use of the following detection reagents:
- Detection of Fab scaffold
- Detection of C-terminal His6-tag (HHHHHH)
- Detection of C-terminal Myc-tag (EQKLISEEDL)
- Detection of C-terminal FLAG M2-tag (DYKDDDDK)
- Detection of C-terminal StrepII-tag (NWSHPQFEK)
Indirect ELISA
The detection of antigen immobilized on microtiter plates is the standard procedure used by AbyD for quality control of purified antibodies. The antigen is incubated in the well at a concentration of 5 μg/ml, and the purified HuCAL antibody (final concentration of 1 μg/ml) is used as primary antibody. Typically, Maxisorp ELISA plates from Nunc are used.
Indirect ELISA – Detection of Fab
CoatingAntigen 5μg/ml, o/n @ 4°CWash2 x PBST
(PBST buffer with 0.05 % Tween 20)Blocking5 % MP-PBST
(PBST containing 5 % milk powder)Wash2 x PBSTPrimary ABHuCAL antibody (2μg/ml) 1h @ RT in PBST or HiSpec BufferWash5 x PBSTSecondary ABα-Fab-AP conjugate1 (1:5 000 in HiSpec Buffer), 1h @ RTWash5 x PBSTDetectionAttoPhos2 (1:10 in H2O)
Indirect ELISA - Detection of c-terminal His6-tag
CoatingAntigen 5 μg/ml, o/n @ 4°CWash2 x PBST
(PBST buffer with 0.05 % Tween 20)Blocking5 % MP-PBST
(PBST containing 5 % milk powder)Wash2 x PBSTPrimary ABHuCAL antibody (2 μg/ml) 1h @ RT in PBST or HiSpec BufferWash5 x PBSTSecondary ABα-His6-HRP.
(1:400 in HiSpec Buffer), 1h @ RTWash5 x PBSTDetectionQuantaBlu Peroxidase Substrate, soluble
Indirect ELISA - Detection of c-terminal myc-tag
CoatingAntigen 5 μg/ml, o/n @ 4° CWash2 x PBST (PBS buffer with 0.05 % Tween 20)Blocking5 % MP-PBST (PBST containing 5 % milk powder)Wash2 x PBSTPrimary ABHuCAL antibody (2μg/ml) 1h @ RT in PBST or HiSpec BufferWash5 x PBSTSecondary ABα-c-myc-HRP5
(1:100 - 1:500 in HiSpec Buffer), 1h @ RTWash5 x PBST
Detection
QuantaBlu Peroxidase Substrate: Indirect ELISA – Detection of c-terminal FLAG M2-tag
CoatingAntigen 5 μg/ml, o/n @ 4°CWash2 x PBST
(PBS buffer with 0.05% Tween 20)Blocking5% MP-PBST
(PBST containing 5% milk powder)Wash2 x PBSTPrimary ABHuCAL antibody (2μg/ml) 1h @ RT in PBST or HiSpec BufferWash5 x PBSTSecondary ABα-FLAG M2-HRP7
(1:100 - 1:1000 in HiSpec Buffer), 1h @ RTWash5 x PBSTDetectionQuantaBlu Peroxidase Substrate (1:10 in H2O)
Indirect ELISA – Detection of c-terminal Strep-tagII
CoatingAntigen 5 μg/ml, o/n @ 4°CWash2 x PBST
(PBS buffer with 0.05% Tween 20)Blocking5% BSA-PBSTWash2 x PBSTPrimary ABHuCAL antibody (2μg/ml) 1h @ RT in PBST or HiSpec BufferWash5 x PBSTSecondary ABStrep-Tactin HRP conjugate
(1:4000 in 0.5% BSA-PBST), 1h @ RTWash5 x PBSTDetectionQuantaBlu Peroxidase Substrate.
Western Blot
The amount of antigen material loaded on the gel depends on the sensitivity of the detection system. For initial testing, use 200 μg of cell lysate proteins or 300ng of pure antigen. The purified HuCAL antibody should be used at a final concentration of 1 to 10 μg/ml. We recommend a starting concentration of 5 μg/ml.
For chemiluminescent detection, the system of choice is the use of an HRP conjugate in combination with a chemiluminescent substrate (e.g. ECL Plus, GE Healthcare). Alternatively, the BCIP/NBT substrate (AbD Serotec #BUF045A) can be used for alkaline phosphatase conjugates.
Western Blot - Detection of Fab
SDS-PAGEload 10ng-1μg antigen/laneBlottransfer to a PVDF membrane according to standard protocolsBlocking5 % MP-TBST (TBS containing 0.05 % Tween 20 and 5 % milk powder)WashRinse blot with TBSTPrimary ABHuCAL antibody (1 to 10μg/ml), 1 h @ RT in 1 % MP-TBSTWash3 x 5 min with generous amount of TBSTSecondary ABα-Fab-HRP conjugate
(1:5000 in 1 % MP-TBST), 1h @ RTWash3 x 5 min with generous amount of TBSTDetectionECL Plus chemilumenescence substrate
Western Blot - Detection of c-terminal His6-tag
SDS-PAGEload 10ng-1μg antigen/laneBlottransfer to a PVDF membrane according to standard protocolsBlocking5 % MP-TBST (TBS containing 0.05 % Tween 20 plus 5 % milk powder)WashRinse blot with TBSTPrimary ABHuCAL antibody (1 to 10μg/ml) 1h @ RT in 1 % MP-TBSTWash3 x 5 min with generous amount of TBSTSecondary ABα-His-HRP6-POD
(1:500 - 1:1000 in 1 % MP-TBST), 1h @ RTWash3 x 5 min with TBSTDetectionECL Plus chemilumenescence substrate
Western Blot - Detection of c-terminal myc-tag
SDS-PAGEload 10ng-1μg antigen/laneBlottransfer to a PVDF membrane according to standard protocolsBlocking5 % MP-TBST (TBS containing 0.05 % Tween 20 and 5 % milk powder)WashRinse blot with TBSTPrimary ABHuCAL antibody (1 to 10μg/ml), 1h @ RT in 1 % MP-TBSTWash3 x 5 min with generous amount of TBSTSecondary ABα-c-myc-HRP
(1:100 - 1:500 in 1 % MP-TBST), 1h @ RTWash3 x 5 min with generous amount of TBSTDetectionECL Plus chemilumenescence substrate
Western Blot – Detection of c-terminal FLAG M2-tag
SDS-Pageload 10ng-1μg antigen/laneBlottransfer to a PVDF membrane according to standard protocolsBlocking5% MP-TBST (TBS containing 0.05% Tween 20 and 5% milk powder)WashRinse blot with TBSTPrimary ABHuCAL antibody (1 to 10μg/ml), 1h @ RT 1 % MP-TBSTWash3 x 5 min with generous amount of TBSTSecondary ABα-FLAG M2-HRP
(1:100 - 1:1000 in 1 % MP-TBST), 1h @ RTWash3 x 5 min with generous amount of TBSTDetectionECL Plus chemilumenescence substrate
Western Blot – Detection of c-terminal Strep-tagII
SDS-Pageload 10ng-1μg antigen/laneBlottransfer to a PVDF membrane according to standard protocolsBlocking10% BSA-TBST, 1h @ RT (TBS buffer with 0.05% Tween 20 and 10% BSA)WashRinse blot in TBSTPrimary ABHuCAL antibody (1to 10μg/ml), 1h @ RT in 1% BSA-TBSTWash3 x 5 min with generous amount of TBSTSecondary ABStrep-Tactin HRP conjugate
(1:4000 in 1% BSA-TBST), 1h @RTWash3 x 5 min with generous amount of TBSTDetectionECL Plus chemilumenescence substrate