United Kingdom (UK)
Recombinant monoclonal antibody to Mesothelin. Manufactured using AbAb’s Recombinant Platform with variable regions (i.e. specificity) from the hybridoma K1.
UniProt Accession Number of Target Protein: Q13421
Alternative Name(s) of Target: MSLN; CAK1 antigen; Pre-pro-megakaryocyte-potentiating factor
Immunogen: The original antibody was generated by immunization of mice with periodate-treated human ovarian cancinoma (OVCAR-3) cells. These mice had previously been made tolerant to normal human kidney membranes.
Specificity: This antibody can bind the human mesothelium, expressed on many cancer cells like ovarian carcinoma.
Application Notes: This antibody was used for the study and characterization of CAK1 antigen present on ovarian cancers and normal mesothelium. The initial screening of the mesothelin reactive clones to live OVCAR-3 cells was done using immunofluorescence. Secondary screening was done using immunoperoxidase histochemistry on cryostat sections of normal human tissues and human tumors. Quantitative ELISA confirmed that K1 and OC125 antibodies bind to different epitopes on the OVCAR-3 cells (PMID: 1735605). This antibody can detect mesothelin in a western blot assay. Competition RIA was used to detect the presence of CAK1 antigen in the supernatent of protease or phosphatidylinositol-phospholipase C treated cells. An immunotoxin composed of K1 antibody and native Pseudomonas exotoxin was found to be selectively cytotoxic to cells expressing CAK1 antigen (PMID: 1727378). The affinity of K1 antibody to mesothelin was Kd= 8 nM and determined using surface plasmon resonance (BIAcore assay) (PMID: 9178820).
Antibody first published in:
Chang et al. Isolation and characterization of a monoclonal antibody, K1, reactive with ovarian cancers and normal mesothelium. Int J Cancer (1992); 50(3):373-81. PMID:1735605
Note on publication:
Describes the isolation and characterization of this antibody.
Immunofluorescence staining of HeLa cells with Anti-Mesothelin (Ab02079) K1 Immunofluorescence analysis of paraformaldehyde fixed HeLa cells stained with the chimeric mouse IgG1 version of K1 (Ab02079-1.1) (1:100 dilution) for 1h followed by Alexa Fluor® 488 secondary antibody (1:1000 dilution), showing membrane and cytoplasmic staining. The nuclear stain is DAPI (blue). Panels show from left-right, top-bottom Ab02079-1.1, DAPI, merged channels and an isotype control. The isotype control was an unknown specificity antibody (Ab00178-1.1) followed by staining with Alexa Fluor® 488 secondary antibody.
Flow cytometry using the Anti-Mesothelin antibody K1 (Ab02079). Paraformaldehyde fixed HeLa cells permeabilized with 0.5% Triton were stained with anti-unknown specificity antibody (Ab00178-1.1; isotype control, black line) or the mouse IgG1 version of K1 (Ab02079-1.1, blue line) at a dilution of 1:100 for 1h at RT. After washing, the bound antibody was detected using a goat anti-rabbit IgG AlexaFluor® 488 antibody at a dilution of 1:1000 and cells analyzed using a FACSCanto flow-cytometer.