CD (cluster of differentiation) molecules are membrane receptors important for immune cell function. They are found on the cell surface and can be entirely extracellular or transmembrane.
While it may seem easy to recognize an extracellular loop by injecting the dedicated peptide epitope, acting on a cell membrane glycoprotein is another matter.
The production of a functional antibody against a transmembrane receptor can be achieved by the unique combination of presenting the native conformation of the antigen to the immune system, excluding irrelevant plasma cell populations and isolating rare clones secreting the antibody of interest.
This was achieved by SYnabs by performing DNA immunization followed by syngeneic whole-cell immunization in proprietary LOU rat species.
We generated LO-CD2a (BTI-322), a functional rat human anti-CD2, which has been shown to have potential use as a T-cell depleting agent (3). Under license from Medimmune, the human version of LO-CD2a was named MEDI-507 and is now known as Siplizumab. Afterward, AstraZeneca subsequently licensed the product to ITBMed Biopharmaceuticals for further organ transplantation testing. Since the beginning of the study, AstraZeneca has been able to generate safety data on more than 400 patients.
In parallel, SYnAbs has generated LO-CD2b and LO-TACT, a therapeutic rat anti-human CD25 (IL2Ra) depleting antibody, already chimerized and tested in clinical trials.
Exhibitor Data Sheet