It may soon be possible to give your own immune system a helping hand by taking a pill that mimics the actions of antibodies.
Scientists at Yale University have created the first synthetic antibodies that can attach to disease causing cells and help target the body's immune response to them.
This mimics the action of natural antibodies which bind to diseased cells and bacteria in the blood stream and encourage white blood cells to kill them.
The scientists say their synthetic antibodies, which can be stored at room
Dr David Spiegel, a chemist at Yale University who has been developing the synthetic antibodies, said the molecules can be taken as a pill like painkillers and antibiotics.
His team have already used their molecules to produce a synthetic molecule that attacks prostate cancer.
They hope similar molecules could be used to develop treatments for other forms of cancer, bacterial infections and even HIV.
Dr Spiegel said: 'Unlike antibodies, our molecules are synthetic organic compounds that are approximately one-twentieth the size of antibodies.
'They are unlikely to cause unwanted immune reactions due to their structure, are thermally stable, and have the potential to be administered orally, just like traditional, small-molecule drugs.'
Doctors already use antibodies in treatments known as monoclonal antibody therapy.
This is a form of immunotherapy that uses natural antibodies created from cells grown in the laboratory.
However, these antibodies tend to be large molecules that are sensitive to temperature change and so need to be stored carefully.
Due to their size they also need to be administered through an injection.
They work by specifically targeting diseased cells and hyjacking the immune system to destroy these cells.
In the human body, antibodies are Y-shaped proteins that are produced by plasma cells in the blood in their billions.
Each molecule contains structures that bind to unique molecules on the surface of foreign cells, known as antigens, allowing them to identify cells that do not belong in the body.
By clumping around these foreign cells they can neutralise them while also attract white blood cells from the immune system that then destroy the danger.
The synthetic antibodies developed by Dr Spiegel and his team, called Synthetic Antibody Mimics, or SyAMs, work in a similar way.
However, they are just a twentieth of the size of natural antibodies, meaning they can pass through the walls of the gut.
This means they can be taken orally as a pill rather than having to be injected.
In work published in the Journal of the American Chemical Society, Dr Spiegal reported that they had designed SyAMs that can bind to a specific antigen on prostate cancer cells.
They are created by combining chemicals in a laboratory, much like conventional drugs, meaning they can also be mass produced.
Currently their SyAMs have only been used on cancer tissue in the laboratory but the researchers are hoping to conduct animal trials shortly.
If successful this could lead to human trials within a few years.
They are also developing SyAMs that are capable of targeting HIV, other cancers and bacteria that cause autoimmune diseases.
Speaking to Scientific American, Dr Laura Kiessling at the University of Wisconsin–Madison who studies antibodies, said the research could allow tailor made treatments.
She said: 'It can be tailored to selectively recruit specific types of immune cells to kill tumor cells.
'The smaller size of the compounds could also be an asset in eliminating tumors, but the benefits would need to be looked at in vivo.'