Activation of the immune system, especially effector T cells, can be harnessed as effective anti-tumor therapy. However, the number of tumor-specific T cells is low, so it can be difficult to activate sufficient numbers of T cells to alter tumor growth. Adoptive transfer of tumor-specific T cells into patients provides a means to treat cancer. Yet, isolation and expansion of large numbers of tumor-specific T cells that retain their antigen specificity and function can be a challenging task.
To activate a large number of T effector cells against tumors in vivo, Dartmouth researchers have now developed a novel bi-specific fusion protein composed of at least a portion of a NK receptor molecule and an antibody variable fragment region (Fv) specific for an effector cell. This bi-specific molecule (with two active binding sites) is called a BiTE (bispecific T cell engager), and it engages effector T cells to target cells, such as a cancer cells. Once bound together, the activated T cell releases effector functions against the bound target cell thereby resulting in activation of host immunity and death of the target cell. This BiTE molecule does not active T cells unless they are bound to target cells, which limits off-target events, and this BiTE has high efficacy at low doses in vivo. Thus, this technology is a novel means to target tumor cells using NK cell receptors to guide effector cells to attack tumor cells. Due to the nature of ligand expression on many different types of tumor cells, these BiTE proteins are useful against many different types of tumors. Because certain ligands can be expressed by virus- or bacterial-infected cells, these fusion proteins may also be used in targeting cells infected by pathogens.
This technology is claimed in a pending patent application. We are seeking an industrial partner interested in its commercialization. (Ref: J546)
Last Updated: 7/24/12