Washington, Sept 20 : A team of researchers at Wake Forest University of Medicine in Winston-Salem, North Carolina have developed a new method in which immune cells from “cancer-resistant” people are to be injected into those with cancer to help fight the disease.

The US Food and Drug Administration (FDA) has granted the researchers permission to screen people for the immune cells’ ability to ward off the disease.

Cancer patients will be given immune cells from the best cancer fighters after being matched for blood type.

All have some ability to fight cancer, through immune cells called NK cells, which can identify and kill tumour cells, although the degree of influence by these cells has not been identified.

But, lead researcher Zheng Cui has found that a much larger population of immune cells called granulocytes can also kill cancer and that the efficiency of these cells differs from person to person.

For the study, Cui took blood samples from more than 100 people and mixed their granulocytes with cervical cancer cells. While granulocytes from one individual killed around 97 per cent of cancer cells within 24 hours, those from another healthy individual only killed around 2 per cent of cancer cells.

Average cancer-killing ability seemed to be lesser in adults after 50 and even lower in people with cancer. It also fell when people were under stress, and during particular times of the year.

“Nobody seems to have any cancer-killing ability during the winter months from November to April,” New Scientist quoted Cui, as saying.

Initial evidence suggests the ability to fight off cancer can be transferred between people. Granulocytes are already taken from donors and given to some patients with depleted immune systems due to chemotherapy, for example, though not to treat cancer directly. And last year Cui successfully treated a range of different cancers in mice by injecting them with granulocytes from a strain of mice that are completely resistant to cancer

“The concept of using immune cells from one person to fight cancer in another person is a very hot topic right now,” said John Gribben, a cancer immunologist at Cancer Research UK’s experimental medicine centre at St Bartholomew’s Hospital, London.

However, there is a risk of graft-versus-host disease.

“If they’re using live cells there is a theoretical risk of graft-versus-host disease, which can prove fatal,” Gribben said.

It is a problem in patients with depleted immune systems, where transfused cells may propagate and capture the host’s immune system, destroying cells in the bone marrow.

Cui says he is working with the FDA to minimise this risk. (With inputs from ANI)