NEWS OF THE WEEK and which the stratospheric ozone lay er screens from Earth's surface. But to the researchers' surprise, the con trol fish, not exposed to UV-B, also devel oped melanoma. 'Tart way through our experiments, we realized that longer wavelengths that come through the glass of the aquarium also give melanomas," Setlow says. The team concluded after further ex periments that UV-A (320 to 400 ran) and visible radiation, which are not ap preciably absorbed by DNA and which are much more abundant in sunlight than UV-B, induce melanoma in the fish. The team hypothesizes that the energy from longer wavelengths of light absorbed by melanin—the brown ish-black pigment found in skin cells— may be transferred to some other com pound that then damages DNA. "My personal opinion is we can ex trapolate these results to humans," Setlow says. "As far as we know, the pho tochemical reactions of DNA are inde pendent of source, fish or human. And the fish have melanocytes—cells con taining melanin—like humans." On the basis of their work, the re searchers point out that sunscreens de signed to protect against burning UV-B rays may not guard against melanoma. They also note that ozone absorbs sig nificantly only at wavelengths under 320 ran, so depletion of the ozone layer likely would have only a minor effect on the incidence of melanoma.
protect someone from infection by the virus. The work was carried out by a team led by David H. Schwartz of Johns Hopkins University School of Hygiene & Public Health, Baltimore, Md., and is published in the July 10 issue of Lancet [342, 69 (1993)]. The vaccine is based on a recombinant version of gpl20, HIV-l's envelope gly coprotein. It was derived from a labora tory strain of HIV-1 not typically seen in AIDS patients. The vaccine, produced by the California biotechnology firm Genentech, previously was shown to pro tect chimpanzees exposed to the virus. In the Johns Hopkins trial, 10 volun teers received 300^g doses, 10 received 100 μg, and eight got a placebo. The doses were given in three injections over the course of 32 weeks. Nine of the 10 high-dose vaccinées and five in the low-dose group produced antibodies that neutralized the virus strain from which the vaccine was made. Six of the nine who responded to the high dose also produced antibodies against a different strain that is much more common among AIDS patients. Such cross-reactivity is considered an important feature of a practical AIDS vaccine. No significant side effects were seen.
Pamela Zurer
Hong Kong's government is spurring birth of a high-value-added chemical industry in its New Territories region. The government will implement the advice of studies it commissioned that call for setting aside portions of established industrial areas. Reclamation of these sites is needed to permit building chemical plants. A total of more than 300 acres has been designated for reclamation and subsequent development for chemical industry. These actions follow recent construction of a world-class chemical waste treatment plant on Tsing Yi Island near Hong Kong's Kowloon Peninsula. Hong Kong's philosophy has always placed emphasis on high-value-added and "high-tech." But it is particularly pushing development of industries now so as to have as many as possible functioning before reintegration with China on July 1,1997. The basic agreement between the U.K. and China stipulates that what is in place in Hong Kong in 1997
Prototype AIDS vaccine shows promise in tests Early tests of a genetically engineered AIDS vaccine in human volunteers show that it is the first such vaccine to elicit consistent levels of potent antibod ies against HIV-1, the virus that causes AIDS. Scientists say the results are encourag ing but stress the vaccine is only a proto type, not a formulation that will be test ed in larger scale trials. So the study is not expected to lead to a practical AIDS vaccine anytime soon. The vaccine was tested in 20 healthy volunteers at low risk for infection by the AIDS virus. The HIV-1 antibodies that showed up in their blood were found to neutralize the virus in vitro. But no one knows if these antibodies can 8
JULY 19,1993 C&EN
Antibody levels were much higher than in previous AIDS vaccine tests, notes Patricia E. Fast, who heads the AIDS Vaccine Evaluation Group at the National Institute of Allergy & Infectious Diseases, which funded the study. But no one knows what antibody levels are necessary to protect people from infection, she adds. Most high-dose vaccinées also produced antibodies that inhibit formation of syncytia, giant cells formed by fusion of HIV-infected and uninfected cells. A similar vaccine trial currently is under way involving the MN strain of HIV-1, which is thought to be more typical of the strains found in U.S. and European patients. An MN-derived vaccine may be a more appropriate candidate for efficacy trials, the researchers say. Before a vaccine can be approved for human use, it must be tested in thousands of healthy volunteers at risk of HIV infection. More than 20 experimental AIDS vaccines are in various stages of human testing around the world. A vaccine for general use is at least five to 10 years away, scientists say. The Lancet study is "a significant step, [but] there's a long way to go," Fast remarks. Ron Dagani
Hong Kong spurs birth of a chemical industry will be allowed to function for at least 50 years as a capitalist enclave within socialist China. Two principal sites have been selected for development of chemical processing plants—Tuen Mun and Teung Kwan Ο—envisioning a mix of polyes ter, acetal, and styrene production facil ities. Both sites will be provided with appropriate pipelines, bulk storage fa cilities, and docking facilities for barges and ships. Reclamation of the Tuen Mun site will begin in mid-1994, with completion scheduled for 1999. No date has been set to start reclamation at Teung Kwan O. The specification of polyester, acetal, and styrene plants for Tuen Mun does not include the names of the compa nies that will operate the plants. Specu lation includes the Taiwan-based For mosa Plastic Group, joint ventures by European and American companies, and investment by China itself. Joseph Haggin
