Shape of antibody makes a difference in fighting cancer

Date: Dec-16-2014 Using antibodies to boost the immune system's ability to tackle

disease is a relatively new approach that is transforming cancer treatment.

Now a new study shows that the shape of an antibody can make a big difference

to the effectiveness of so-called cancer immunotherapy.

Researchers found they could engineer antibodies with a particular structure that makes them much more effective at getting the immune system to attack cancer cells.

Researchers from the University of

Southampton in the UK found a particular naturally occurring

antibody called IgG2 is much more effective at stimulating the immune system

to fight cancer than other types of antibody.

They report their findings in the journal Cancer Cell.

Study leader Dr. Ann White, Senior Research Fellow at Southampton,

says:

"We know that the immune system provides a natural protection against

cancer, which can only grow by finding a way around our defences."

Antibody

treatments are now able to correct this problem for many types of cancer, but

we still need them to work better," she adds.

Engineered antibodies with particular shape make stronger immune

stimulators

IgG2 is unique among antibodies because it can work on its own without the

help of other immune cells. This makes it more active and effective in all

tissue types.

The team found that a version of the antibody - IgG2B - is particularly

effective at stimulating antitumor immunity because it has what is known as a

"locked B structure."

The team also found they could engineer antibodies to have this particular

shape - thus opening the door to making stronger immune stimulators than

previous drugs.

Dr. White notes that while it is early days, a discovery like this could

enable doctors to treat cancer more effectively.

"Our next task is to bring these novel IgG2B antibodies into trials for

cancer patients and we are engineering ways to make them effective in the

clinic," she adds.

Researchers now trying to discover why antibody shape is important

The researchers are now trying to discover why IgG2 works better in a

locked B structure.

They have crystallized the molecule and shone X-rays through it to better

understand its structure.

To their knowledge, this is the first time anyone has crystallized

IgG2.

Professor Nic Jones, chief scientist at Cancer Research UK, the sponsor of

the study, comments:

"Energizing the immune cells in our body and getting them to treat cancer

cells as a threat gives us a better shot at beating cancer."

The study is part of growing research in the field of cancer immunotherapy at the University of Southampton.

In June 2014,  Medical News Today learned how researchers

found that combining a vaccine with low-dose chemotherapy could make pancreatic cancer susceptible to the effects of

immunotherapy.

That study could make a big difference because typically, pancreatic cancer

does do not respond to immunotherapy, and fewer than 5% of patients survive 5

years after diagnosis.

Written by Catharine Paddock PhD

Not to be reproduced without permission.

Follow @twitter

window.twttr = (function (d, s, id) {
var t, js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) return;
js = d.createElement(s); js.id = id;
js.src= "https://platform.twitter.com/widgets.js";
fjs.parentNode.insertBefore(js, fjs);
return window.twttr || (t = { _e: [], ready: function (f) { t._e.push(f) }
}(document, "script", "twitter-wjs"));

Courtesy: Medical News Today Note: Any medical information available in this news section is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional.