Anti-CD133 Monoclonal Antibodies as Cancer Therapeutics

Most early work on CD133 was carried out using one of two monoclonal antibodies (mAbs), AC133 and AC141, which recognize an undefined glycosylated epitope of CD 133.

Researchers from NCI's Pharmacodynamic Assay Development and Implementation Section generated novel anti-human CD133 monoclonal antibodies from large extracellular domain loops of CD133 using peptide residues selected from the native extracellular domains of CD133 protein as an immunogen. They selected sequences for immunization that do not overlap with known glycosylation sites. Peptide antigens comprising the amino acids in the extracellular domain were synthesized and conjugated to carrier proteins as the immunogen.  A key step was screening for specificity using peptides and expressed recombinant extracellular domains of CD133. The resulting antibodies recognize both glycosylated and non-glycosylated regions of the cognate antigen. The inventors have demonstrated the utility of this invention in immunofluorescence assay, western blotting and ELISA, flow cytometry, and immunoprecipitation. NCI seeks licensing and/or co-development research collaborations for commercializing the use of antibodies against CD-1333. 

Competitive Advantages:

- High specificity anti-CD133 monoclonal antibody that has the ability to bind to both glycosylated and unglycosylated epitope of CD133

Commercial Applications:

- Biomarker to CD133 useful for immunofluorescence assay
- Western blot 
- ELISA 
- Flow cytometry
- Immunoprecipitation