Research hints at new strategies against AIDS "Too much pessimism has been expressed in the past year with regard to controlling HIV in people who are already infected with the virus." So said Robert C. Gallo, director of the National Cancer Institute's Laboratory of Tumor Cell Biology, in opening his plenary lecture at the 7th International Conference on AIDS last week in Florence, Italy. HIV is the human immunodeficiency virus, the cause of AIDS. Gallo outlined a number of discoveries by researchers in his lab on the molecular biology of HIV that, down the road, could lead to new strategies for combating the virus. That work and research results presented by other scientists at the conference reinforce the notion that HIV is a formidable but not invincible foe. For example, Gallo says Franco Lori, one of his collaborators, has made the startling discovery that some mature HIV particles contain a small amount of viral DNA tightly complexed with the virus's reverse transcriptase enzyme. HIV is a retrovirus, and the genetic material of retroviruses is RNA, not DNA. If this HIV-DNA is involved in some phase of the viral life cycle—and Gallo and Lori believe it is—it may open new strategies for attacking HIV. Another researcher in Gallo's lab, Julianna Lisziewicz, has shown that inserting multiple copies of an HIV regulatory gene, tar, into the genome of a T lymphocyte blocks subsequent HIV replication after the virus infects the cell. The idea is that the HIV regulatory protein Tat— which acts by binding to the mRNA product of tar—is overwhelmed by the multiple copies of tar mRNA produced when the T cell is activated. This finding is the first step toward a possible gene therapy strategy for AIDS patients, Gallo says. At the University of California, San Francisco, AIDS researcher Jay A. Levy and coworkers are investigating other aspects of the molecular biology of AIDS that could lead to treatments for the disease. For example, the team has shown that a
factor produced by cytotoxic T lymphocytes taken from individuals infected with HIV but without symptoms of disease suppresses HIV replication in infected T cells without killing the cells. Levy calls the factor a "novel, previously undescribed cytokine." His team is working to characterize the new factor, which obviously could have use for treating AIDS patients. While these and other basic research advances are encouraging,
the news from epidemiologists at the meeting was bleak. The World Health Organization estimates more than 1 million people have gotten AIDS since the pandemic began in 1981. At least 8 million to 10 million adults around the world have become infected with HIV, and about 1 million children have been born infected with it. By the year 2000, WHO projects a total of 40 million HIV infections. Rudy Baum
Recession in plastics may be bottoming out The U.S. may be in a recession, but it wasn't obvious—superficially, at least—at the National Plastics Exposition, held last week in Chicago. The triennial show, sponsored by the Society of the Plastics Industry, set several new records: The exhibitor list reached 1200, up almost 17% from 1988, and floor space increased comparably. But, at press time, it seemed unlikely that total attendance would reach, let alone exceed, the 1988 record of 73,000. Even if the recession was out of sight, it wasn't out of mind. "Our first quarter felt the full brunt of the recession, with declines in auto builds and housing starts reducing demand for durable goods," notes Edward H. Munoz, vice president and general manager of Hoechst Celanese's engineering plastics division. "But early returns in our second quarter suggest the recession
has bottomed out. One exception is the automotive sector, which we expect will remain very weak." Indeed, SPI statistics for the first quarter show resin .sales down 6.6% from the like period in 1990. Unsaturated polyester sales were down 24%, reflecting conditions in the auto and construction markets. Polystyrene and acrylonitrile-butadienestyrene sales also were off sharply. Nevertheless, there's a "sense that customers are beginning to see the light at the end of the tunnel," says Tony Carbone, Dow's group vice president for plastics. Dow is "very pleased w i t h t h e traffic at t h e show," and order rates and bookings are "impressive," he adds. Joachim R. Harder, vice president of Mobay's plastics d e p a r t m e n t , agrees; his booth was "extremely busy." He was struck by the number and quality of visitors. "We have a
National Plastics Exposition in Chicago hosts record number of exhibitors June 24, 1991 C&EN 5
