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RECORD DONORS: U.S. Healthcare founder Leonard Abramsom and his wife, Madlyn, a cancer survivor, donated $100 million to create a new cancer research center at the University of Pennsylvania Medical Center. Photo: Courtesy Bruce Wemger INJECTION INNOVATION: A young patient shows some apprehension as a needle-free injector device is placed against her arm prior to firing. Remember the terror you felt as a child when you went to the doctor for a vaccination? These days, doctor visits are worse for children. Added to the standard list of measles, mumps, and rubella (often given as one combination injection); diphtheria, tetanus, and pertussis (given as a single DTP vaccine); and polio; now Haemophilus influenzae b, hepatitis A, hepatitis B, and varicella are preventable by vaccination. "In 1989, it took just eight shots to fully immunize a child against the recommended diseases; now, it takes a minimum of 14," says Bruce G. Weniger, assistant chief for vaccine development at the Centers for Disease Control and Prevention's National Immunization Program. To avoid upsetting a child with large numbers of shots given during a single visit, medical personnel often reschedule some injections-but some parents don't bother taking the child back for rescheduled or booster shots. These are good reasons to develop new injection technologies, but there are others, Weniger says. Needlestick injuries from vaccinations and other injections, which can transmit infections to health care workers, cost roughly $500 million per year to treat, not including lost work time, says Weniger. And in developing nations, improper reuse and ineffective resterilization of needles contribute to disease spread. Companies are developing combination vaccines to decrease the numbers of injections, as well as jet injectors with disposable nozzles that shoot a fine stream of vaccine through the skin. But, Weniger warned at a December symposium at the Albert B. Sabin Vaccine Institute at Georgetown University, unless new administration techniques are developed, some new vaccines may languish unused. Photo: Karen Hopkin HEADLINERS: Elvis Presley may be frequently sighted, but Wild Type drummer Ken Kinzler and keyboard player Bert Vogelstein are frequently cited. NIH ROCKERS: From left, Francis Collins, Richard Klausner, and Steve Katz of the Directors help Washington, D.C., science writers ring out 1997. Ebola hemorrhagic fever is still rare (thanks to the efforts of virus fighters) but nevertheless a threat. Traditional vaccine approaches have failed, and researchers do not understand how infection affects host immunity, largely because the disease is so dangerous to study. But hope looms. A group from the University of Michigan in Ann Arbor and the Centers for Disease Control and Prevention (CDC) in Atlanta recently tested an anti-Ebola "genetic vaccine" in laboratory animals (L. Xu et al., Nature Medicine, 4:37-42, 1998). Researchers injected plasmids bearing certain Ebola genes into mice, and the expressed viral proteins elicited low amounts of circulating antibodies and stronger cell-mediated immunity. The vaccine did not encode parts of the virus that are suspected of suppressing host immunity. To assess whether this apparent immune response can prevent disease, the researchers genetically vaccinated guinea pigs, which react to Ebola much as humans do. Like mice, the guinea pigs responded immunologically; they also survived exposure to Ebola up to four months after initial immunization. These results suggest that viral proteins produced in test animals confer immunity while the same proteins injected as traditional vaccines fail. "This de novo synthesis of the virus protein provides a means of presenting antigens to immunocompetent cells that would mimic an actual infection," explains Anthony Sanchez, Public Health Service research officer at CDC and one of the authors of the study. It remains to be seen whether humans will respond in the same way to genetic vaccination. GENETIC VACCINE: CDC's Anthony Sanchez found that guinea pigs survived exposure to Ebola virus, inset, up to four months after initial immunization. On December 14, the United States Food and Drug Administration (FDA) approved Zenapax, a monoclonal antibody that can help to prevent the rejection of acute kidney transplant rejection, for use in humans. The drug, which was initially developed in National Cancer Institute (NCI) laboratories, will be marketed by Nutley, N.J.-based Hoffmann-LaRoche Inc. Two double-blind placebo-controlled randomized trials by Hoffmann-LaRoche showed acute kidney rejection episodes were reduced almost 40 percent in patients taking Zenapax. FDA approval of Zenapax marks the culmination of 16 years of research by Thomas A. Waldmann, chief of the branch of metabolism of NCI. In the early 1980s, Waldmann became interested in the role of T cells in the functioning of a normal immune system as well as their role in immune-related disorders like leukemia and organ rejection. His research on T cells led to several innovations, including the creation of Zenapax's precursor, anti-Tac (T. Uchiyama et al., Journal of Immunology, 126:1393-97, 1981). Clinical trials are now under way to determine if Zenapax is effective in treating uveitis, an autoimmune disorder causing blindness. "I count it as a great success that our initial focus on basic science grew into a discovery that can touch a broad patient population," Waldmann says. A recent study shows the biological sciences both attracting and losing a large share of top students from 1985 through 1995. The study, which tracked the education and career paths of top science and engineering students, was prepared by the Commission on Professionals in Science and Technology (CPST) in Washington, D.C. While the number of top students entering college increased 17 percent from 1985 through 1995, science and engineering's share of those students declined from 29 percent to 24 percent, according to Catherine D. Gaddy, executive director of CPST and one of the study's authors. The report defines top students as those with an "A" grade-point average at entry to college. While the proportion of top students choosing to major in physical sciences remained stable at 3 percent, those choosing to enter fields in engineering and mathematical sciences declined, respectively, from 18 to 10 percent and from 2 to 1 percent. Although biological sciences saw their share of new top students increase from 6 percent to 10 percent from 1985 to 1995, the field's retention of top students was one of the lowest, as only 33 percent went on to graduate in the field. "A similar trend was observed in mathematical sciences," Gaddy says. "We can't explain why this has happened using data alone. But the report shows where university administrators and faculty should direct their concern." More information on the report can be found at www.aaas.org/cpst/. For more than a decade, Winslow Briggs, director, emeritus, of the department of plant biology at the Carnegie Institution of Washington in Stanford, Calif., and colleagues have probed the response of Arabidopsis thaliana, a plant in the mustard weed family, to blue light. In a December paper (E. Huala et al., Science, 278:2120-3, 1997), they reported the surprising finding that two domains of the protein are common to other organisms as well. Blue light is a beacon to a plant. "To a plant growing in a patch of forest, the brightest place appears blue, so it makes sense that a plant aims in that direction. Indirectly, sensing blue light increases photosynthetic activity," Briggs explains. In 1992, he identified a protein in the cell membrane that is phosphorylated in the presence of blue light, an early step in the signal transduction pathway that bends the plant toward light, a response called phototropism. Two related domains of that protein, called LOV1 and LOV2, for "light, oxygen, voltage," have counterparts in diverse organisms: an Archaean, two types of bacteria, a fungus, an insect, and mammals. The proteins apparently sense an environmental stimulus-light, oxygen, or voltage-and then gain or lose an electron, which triggers further cellular responses. "This discovery represents a remarkable evolutionary adaptation of a single basic function to serve widely divergent purposes. The extraordinarily high conservation really blew us away," says Briggs. The researchers do not yet know the precise functions of the domains in the species examined.

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RECORD DONORS: U.S. Healthcare founder Leonard Abramsom and his wife, Madlyn, a cancer survivor, donated $100 million to create a new cancer research center at the University of Pennsylvania Medical Center.