Camelid Nanobodies

Antibodies (also known as immunoglobulins) are proteins that are produced by the body in response to the presence of foreign substances such as bacteria, viruses, certain proteins, and tumor cells- these are all known as antigens. Antibodies are constructed so that they bind very tightly and specifically to an antigen. Antibodies that are produced in laboratories are used in diagnosis, treatment and prevention of a variety of diseases as well as widely used in research.

In 1989, it was discovered that camelid antibodies are different from those of almost every other animal species in that they are missing a part of the protein known as the light chains. These camelid antibodies are still fully functional, and it became apparent that they could be modified to be an even smaller structure known as a nanobody. Nanobodies have several advantages over conventional antibodies in that their small size allows them to get inside cells and to other places that conventional antibodies can’t reach. In addition, their unique structure makes it less likely that they will cause a harmful response if injected into a patient.

At the Carlson College of Veterinary Medicine, Dr. Chris Cebra and his colleagues have been producing nanobodies by injecting llamas and alpacas with certain antigen preparations so that the camelids produce antibodies that can then be modified in the laboratory to be used by researchers and clinicians. Targets so far have been the bacteria that causes tuberculosis, the virus that causes Dengue Fever and proteins that are found in cancer in dogs. The work has been done in collaboration with Oregon Health Sciences University, Case Western Reserve, and other colleges at Oregon State University.

Fun fact: The other animal that produces these “small” antibodies is the shark. It is logistically easier to inject and draw blood from alpacas and llamas than from sharks for obvious reasons.