The immune system is known to protect the body by destroying foreign invaders. But now a team of researchers at Hadassah University Medical Center on Mount Scopus has discovered that it can also build. This previously unknown function plays a major role in pregnancy, with important implications for conditions that cause pre-eclampsia and miscarriages. "Our research revealed that natural killer (NK) cells of the immune system are positive regulators of human cells, in addition to their well-known killing function," says obstetrics and gynecology Prof. Simcha Yagel, whose team's findings have been published in Nature Medicine. "This positive regulation stimulates the immune system to secrete special growth factors, and triggers the tremendous uterine blood vessel widening necessary for the growth and development of the placenta. We know now that without this positive regulation, the placenta would not develop properly. "It's as if we opened a door we never knew existed and entered a completely new world of exciting possibilities." Yagel, Prof. Ofer Mandelboim and Dr. Jacob Hanna (of the Hebrew University-Hadassah Medical School's Lautenberg Center for General and Tumor Immunology) and Dr. Debra Goldman-Wohl (of Hadassah's department of obstetrics and gynecology) and colleagues discovered this previously unknown feature using both cellular and molecular biology to advance their understanding of maternal-fetal interaction. "What we have learned about the immune system will have significant impact on many aspects of problematic pregnancies as well as the In Vitro Fertilization process. In the future, our research may help us remedy or prevent these conditions," Yagel says. "The placenta is the connection between mother and fetus. If the placenta doesn't develop properly, it impedes implantation of the fetal cells," he explains. "Shallow fetal cell implantation is a hallmark of pre-eclampsia - a condition that develops in late pregnancy caused by vascular problems of the placenta. Our discovery could lead to a treatment that reduces the incidence of pre-eclampsia, a condition that affects 7% of all pregnant women and may have therapeutic implications on recurrent miscarriage," he says. "In the next stage of our research, we will continue to explore the precise immune receptors for a better understanding of how they function, and ultimately, how they can help ensure healthy babies." TRAUMA CENTERS IN NORTH Five government centers for the treatment of emotional trauma have opened in Haifa, Safed, Nahariya, Nazareth and Tiberias to follow up patients who suffered anxiety attacks from Hizbullah's rocket attacks during the recent conflict, the Health Ministry says. The special cabinet committee for strengthening the North decided to allocate NIS 4.5 million for these centers, which are located at Rambam Medical Center, Ziv Hospital, Western Galilee Government Hospital, Scottish Hospital and Poriya Hospital. Doctors and nurses are undergoing special training to identify patients suffering from anxiety and stress so they can prevent them from developing post-traumatic stress disorder. FISH OIL CAPSULES BENEFICIAL Omega-3 fatty (fish oil) capsules may prevent more sudden deaths than automated external defibrillators in homes and public places or implanted defibrillators, according to the results of a new Minnesota study. Researchers compared these preventive strategies in a computer-simulated community of 100,000 people that resembled the population of Olmsted County in 2000. By raising omega-3 fatty acids levels among the cyber-Olmsted citizens, Dr. Thomas Kottke and colleagues at the Heart Center in St. Paul were able to lower overall death rates in the simulated population by 6.4%. By contrast, investing in automated external defibrillators (AEDs) reduced death rates by only 0.8%, and implanted defibrillators (ICDs) reduced deaths by 3.3%. The study, to be published in the American Journal of Preventive Medicine, showed that raising omega-3 fatty acids "would have about eight times the impact of distributing AEDs and two times the impact of implanting ICDs," Kottke said. Three-quarters of the reduction in deaths from increased omega-3 fatty acid levels would come from raising omega-3s among the healthy portion of the population, the researchers said. Although previous studies have shown that omega-3 fatty acids and defibrillators can prevent sudden cardiac deaths, it is difficult to compare their effectiveness across a population. For instance, people who suffer from a cardiac condition can be prescribed a series of treatments, and may follow their doctors' orders to different degrees. To keep these types of variables under control, Kottke and colleagues developed the computer simulation, which combined realistic data on patient health and treatments with unrealistic conditions such as 100% patient compliance. Raising blood levels of omega-3 fatty acids after a cardiac event such as a heart attack could save 58 lives a year, according to the simulation's predictions. Only seven lives per year were saved by AEDs, while implantable defibrillators prevented 30 deaths each year under simulation conditions. "Despite the fact that AEDs do save lives, they are unlikely to ever have a substantial impact on rates of sudden death," Kottke said, explaining that a whole chain of events - from speedy application of the device to surviving in the hospital - has to occur to save a person with an AED.