A retrovirus that causes leukemia in humans may be slipping in undetected blood reserves, claim researchers in the issue tomorrow of Proceedings of the national Academy of sciences . But other researchers familiar with the work counter that there is no cause for alarm.
Each pint of blood donated in the United States is satisfied for many viruses, including hepatitis, HIV, and type of human T-lymphotropic virus 1 (HTLV-1), which can lead to leukemia. But Dorothea Zucker-Franklin of the University of New York and his colleagues say they have found evidence that the fragments of the virus escape detection by current tests. The researchers tested blood samples from 81 former intravenous drug users. Using the polymerase chain reaction (PCR), the researchers found that 48% made from an HTLV-1 gene, but only 22% of them were positive for anti-HTLV-1 antibodies which are commonly used to screen the virus. "I am very concerned," said Zucker-Franklin, a hematologist. "I do not think we should transfuse people with cells that have these [viral] sequences."
Although Zucker-Franklin said it has no evidence that someone has been infected with HTLV-1 gene, called tax , following a transfusion, she added that privacy issues prevented him from studying people who received tax of . blood-contaminated and while there is no evidence that anyone hosting tax suffered any illness of her, she noted that the gene is particularly worrying because - at least in studies test tubes - it can turn cancer cells
"it is a major contribution if it is true," said Institute of Human Virology head Robert Gallo, whose isolated laboratory for the first HTLV-1. . specifically, he said, it could lead researchers to probe into the cancer cells for single genes such as tax . Because the virus under the same share of the family genes, Gallo said, the work also raises the possibility that there is yet another virus in the two members of the HTLV family.
But other experts have their doubts. "I'm not convinced that there is a high prevalence of tax " in people who do not have HTLV-1 antibody, retrovirologist says Michael Busch, of the University of California, San Francisco and Irwin Memorial blood that city centers. Busch says his lab collaborated with Zucker-Franklin on an analysis of tax in HTLV-1-positive and HIV-negative blood samples. "the results were inconsistent, "he said. and in larger studies with blood donors, his team found no pieces of viruses that evade antibody-based tests." HTLV is the last thing I would be concerned, "he said.
0 Komentar