llama antibodies

When a Llama Is Laid Back, It's Not the Only Beneficiary

The engines of innovation for a promising new class of pharmaceuticals are covered in soft hair and tend to spit when irritated.

Scientists are exploiting an unusual feature of the immune system of llamas -- a South American relative of the camel -- to develop new treatments for diseases including rheumatoid arthritis, cancer and Alzheimer's. Llamas, camels and their alpaca relatives are one of only two animal families that create extremely small antibodies, the molecules that are the soldiers of the immune system.

Antibody technology has produced a number of blockbuster drugs over the past decade, such as the cancer treatments Avastin and Erbitux and the arthritis drug Enbrel. Antibodies can be programmed to target proteins that are responsible for diseases, just like a vaccine prepares the immune system to fight viruses. They deliver drugs directly to the troublesome proteins responsible for the disease or block the action of the proteins themselves, stopping the progression of the disease.

But conventional antibodies are large, complex molecules that aren't very durable and have trouble finding their way around the body's tiny crevices. Scientists hope the tiny antibodies found in llamas and camels -- about one-tenth the size of human antibodies -- can burrow into the densely packed cells of a cancerous tumor, slip their way through the blood-brain barrier to block the build-up of plaques that cause Alzheimer's, or settle into the crevices of joints to prevent arthritis. ....