Chimeric Molecule Shows Chemotherapy Potential

A recent study describes the development of a new cancer chemotherapy method based on a genetically engineered fusion molecule that is a combination of a specific anti-cancer cell monoclonal antibody on one end and a major histocompatibility complex (MHC) viral antigen on the other.

Investigators at the Technion-Israel Institute of Technology (Haifa, Israel) created recombinant chimeric molecules through the genetic fusion of single-chain (sc) Fv Ab fragments, specific for tumor cell surface antigens, to monomeric scHLA-A2 complexes containing immunodominant viral-specific peptides. The monoclonal antibody allowed the molecule to bind to a specific type of cancer cell, while the exposed viral antigen acted as an attractant for antiviral T cells.

Results published in the June 17, 2004, online edition of the Proceedings of the [U.S.] National Academy of Sciences revealed that the fusion protein efficiently induced tumor cell lysis, regardless of the expression of self peptide-MHC complexes. Moreover, these molecules exhibited very potent antitumor activity in vivo in nude mice bearing pre-established human tumor xenografts.

"Our approach is to use antiviral T cells to kill tumors,” said Dr. Yoram Reiter, professor of biology at the Technion. "Tumor-specific T cells are very rare and not very efficient. On the other hand, the body has very efficient antiviral T cells, because throughout our lives we are exposed to many viruses such as influenza. These cells are very efficient at recognizing cells that do not belong.”




Related Links:
Technion-Israel Institute of Technology