Monoclones may revolutionise medicine

Press, 24 October 1984, Page 6

Monoclones may revolutionise medicine

NZPA-PA Boston The awarding of the Nobel Prize in Medicine to the developers of monoclonal antibodies comes just as their discovery is finding workaday uses that could revolutionise the diagnosis and treatment of diseases from herpes to cancer. The beauty of these chemicals is their ability to Soint targets inside the \ . germs, particular blood cells, even single cancer cells, so that they can be identified or destroyed.

“I think it is one of the major contributions to biomedical research in the last 30 years,” said Dr Jack R. Wands of Massachusetts General Hospital. “It touches all branches of research from basic immunology to clinical applications such' as, potentially, cancer chemotherapy. It has had an enormous impact and will continue to do so.” Dr Wands is one of the scientists at dozens of universities and hospitals around the world who are looking for ways to harness these substances to cure disease. The Nobel Prize for Medicine was given to Drs Georg Koehler of West Germany and Cesar Milstein of Argentina for discovering how to produce monoclonal antibodies. Dr Niels Jerne, a British citizen who works in Switzerland, was also recognised for basic research into the body’s immune defences. Antibodies are chemicals produced by blood cells. They latch on to foreign substances, such as bacteria, and mark them for destruc-

tion by other parts of the immune system. They do this by recognising specific sites called antigens that sit on the surface of the invader. Each cell has millions of different antigens, and the body produces a host of antibodies, each sensitive to a different site, as it goes about its daily business of keeping a human healthy. Isolating one of these antibodies and then manufacturing it in bulk was an important advance. The result was a pure or monoclonal antibody, which recognises only a single antigen. The manufacturing process has now been appEed to a variety of antibodies, and these monoclonal antibodies provide a handy tool in many different branches of medicine. , They are already finding a practical apphcation in diagnosing diseases. A big problem of modem medicine is determining what germs are making people sick. Growing the bugs in cultures can take weeks, so doctors often must guess which antibiotics will work best Monoclonals can be made that wiU latch on to a teUtale antigen that is possessed by just one germ. Using a blood sample, doctors can now learn in hours what kind of microbe is causing the illness. The Food and Drug Administration, a Government agency that regulates the drug business, already has approved more than 60 of these diagnostic products for marketing. Among

potential uses are antibody tests that will spot such diseases as herpes simplex virus, chlamydia and gonorrhoea. Among other uses of monoclonals: © They can find cancers in the body that are too small to be identified any other way. Dr Wands has developed a variety that reveals Ever cancer whUe it still can be removed surgicaUy and cured. @ Monoclonals that find cancers may also be able to kill them. The idea is to bond the antibody with a poison to produce a kind of guided missile that wiU zero in on the tumour and wipe it out • Day-after therapy for disease may also be possible. Doctors hope to make antibodies that will target specific microbes and give them to people who have been exposed to the germs. Then then- own immune systems will take over and keep them from getting sick. • They are also making bone ’marrow transplants more practical for people with leukaemia and other diseases. One approach is to destroy aU of the victim’s cancerous bone marrow except for a single sample, use monoclonals to kill the cancerous cells in the sample and then put it back in the patient, where it produces new marrow. Another approach is to remove potentially dangerous blood cells from donated marrow and use this for a transplant. '