Ab ID Card application validation / characterisation
WB Validation
Over-expression/cross reactivity
To confirm the lack of cross-reactivity with the other TOX family members, Western blotting of the NAN448B mAb was performed using cell extracts of MYC-FLAG tagged human TOX, MYC-tagged TOX2 and GFP-tagged TOX3 and TOX4. Two bands of 68 kDa and 57 kDa were detected by WB only in the HEK-TOX cell extracts. Anti-GAPDH was used as loading control.
The specificity of the NAN448B mAb for the endogenous TOX protein was confirmed by WB using cell extracts of MOLT4 cell line before (MOLT4 WT) and after TOX gene inactivation (MOLT4 KO TOX) using CRISPR-Cas9 technology. Anti-vinculin was used as loading control.
WB using the NAN448B mAb showed 68 kDa and 57 kDa bands of TOX protein in the SUDHL4 diffuse large B-cell lymphoma cell line. TOX was not expressed in the U266 myeloma cell line. Anti-GAPDH was used as a loading control.
To confirm lack of cross-reactivity with the other TOX family members, immunocytochemistry (ICC) with the NAN448B mAb was performed on frozen cytospin preparations of MYC-tagged human TOX and TOX2 and GFP-tagged TOX3 and TOX4 proteins expressed in HEK293T cells. Staining was observed only of the TOX transfectants. Labelling with the anti-MYC and anti-GFP confirmed the efficiency of transfection.
The specificity of the NAN448B mAb for the endogenous TOX protein was confirmed by ICC in cytospin preparations of the MOLT4 cell line before and after (MOLT4 KO TOX) gene inactivation using CRISPR-Cas9 technology. TOX nuclear expression was observed in wild type MOLT4 cells, while no staining was observed in the MOLT4 KO TOX cells.
Single immunoperoxidase labelling in tonsil of the NAN448B mAb shows strong nuclear staining of TOX in germinal centre cells and cells in the interfollicular area. (B) TOX is also highly expressed by cells in the thymic cortex. (C) In spleen, TOX is expressed by scattered cells in the white and red pulp.
To confirm the lack of cross-reactivity with other TOX family members, flow cytometry was performed using the NAN448B mAb on HEK293T cells transfected with human TOX (light blue), TOX2 (pink), TOX3 (purple), and TOX4 (light blue) plasmid vectors.
Control experiments using only the secondary antibody showed no staining for HEK293T TOX (dashed blue line), TOX2 (dashed pink line), TOX3 (purple line), and TOX4 (dashed light blue line).
The specificity of the NAN448B mAb for detecting endogenous TOX protein was confirmed by flow cytometry using a MOLT4 cell line before (blue) and after TOX gene inactivation (MOLT4 KO TOX, pink) using CRISPR-Cas9 technology.
Control experiments using only the secondary antibody showed no staining for MOLT4 Ko TOX (dashed pink line) and MOLT4 (dashed blue line).
Flow cytometry using the NAN448B mAb shows endogenous TOX protein in the MOLT4 cells (blue) but not in the U266 cells (pink).
Control experiments using only the secondary antibody showed no staining for U266 (dashed pink line) and MOLT4 (dashed blue line).