BiTE (acronym for "bi-specific T-cell engagers"), a class of specific modified antibodies that direct a host's
T cells cytotoxic activity against diseased cells (e.g cancercells).
Several products that have come under close scrutiny in a few preclinical and early clinical studies have produced promising results. Advantages of treatment with BiTEs, which is a kind of
immunotherapyis its specificity, potency and relatively mild side effects (at least compared to side effects of chemotherapy).
BiTEs form a momentary link between T cells and tumor cells that elicits cytotoxic T cells' activity on tumor cells. This action mimicks physiological processes observed during T cell attacks against tumor cells. Proteins like perforin and granzymes enter tumor cells from T cells and initiate the cell's apoptosis. This way not only the primary tumor is destroyed but also even microscopic metatases.
Even small concentrations of BiTE antibodies have been demonstrated to be exceptionally effective due to T cells proliferation in the course of the killing process. The additional therapeutic effect might be augumentation of host's immune system.
Examples of BiTE drugs:
Blinatumomab(MT103) - used in non-Hodgkin’s lymphoma, and acute lymphoblastic leukemia, that is directed towards CD19, a surface molecule expressed on B cells
* MT110 - used in treatment of gastrointestinal and
lung cancers which targets the EpCAMantigen
Utilizing the same technology
melanoma(MCSP specific) and acute myeloid leukemia( CD33specific) neoplasms can be targeted but this research is currently ongoing. Another avenue for a novel anti-cancer therapy would be re-engineering some of currently used conventional antibodies like trastuzumab, cetuximab, and panitumumabto use BiTE approach.
* [http://www.micromet.de/index.php?id=67 About BiTE technology] from Micromet Inc.
* [http://typo3.micromet-inc.com/fileadmin/template/main/pdf_en/bite_backgrounder.pdf 3 page summary by Micromet Inc.]
* [http://www.cancernetwork.com/display/article/10165/1165525 "Novel BiTE antibody mediates contact between T cells and cancer cells"] cancernetwork.com
* [http://pharmalicensing.com/public/outlicensing/view/4943/ige-specific-bite-antibodies-in-allergy-and-asthma IgE-specific BiTE Antibodies in Allergy and Asthma ]
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