"In a bold new approach ultimately aimed at trying to cure AIDS scientists used genetic engineering in six patients to develop blood cells that are resistant to HIV the virus that causes the disease.  Its far too early to know if this scientific first will prove to be a cure or even a new treatment. The research was only meant to show that so far it seems feasible and safe.  The concept was based on the astonishing case of an AIDS patient who seems to be cured after getting blood cells from a donor with natural immunity to HIV nearly four years ago in Berlin. Researchers are seeking a more practical way to achieve similar immunity using patients own blood cells.  The results announced Monday at a conference in Boston left experts cautiously excited.  For the first time people are beginning to think about a cure as a real possibility said Dr. John Zaia head of the government panel that oversees gene therapy experiments. Even if the new approach doesnt get rid of HIV completely it may repair patients immune systems enough that they can control the virus and not need AIDS medicines  what is called a functional cure he said.  Carl Dieffenbach AIDS chief at the National Institute of Allergy and Infectious Diseases agreed.  Were hopeful that this is sufficient to give the level of immune reconstitution similar to what was seen with the patient from Germany he said.  This is the first time researchers have permanently deleted a human gene and infused the altered cells back into patients. Other gene therapy attempts tried to add a gene or muffle the activity of one and have not worked against HIV.  The virus can damage the immune system for years before people develop symptoms and are said to have AIDS  acquired immune deficiency syndrome. The virus targets special immune system soldiers called Tcells. It usually enters these cells through a protein receptor or docking station called CCR.  Some people about  percent of whites fewer of minorities lack both copies of the CCR gene and are naturally resistant to HIV. One such person donated blood stem cells in  to an American man living in Berlin who had leukemia and HIV.  The cell transplant appears to have cured both problems but finding such donors for everyone with HIV is impossible and transplants are medically risky.  So scientists wondered Could a patients own cells be used to knock out the CCR gene and create resistance to HIV  A California biotechnology company Sangamo SANGuhmoh BioSciences Inc. makes a treatment that can cut DNA at precise locations and permanently edit out a gene.  Dr. Jacob Lalezari director of Quest Clinical Research of San Francisco led the first test of this with the company and colleagues at the University of California in San Francisco and Los Angeles.  He warned that it would be way overstated to suggest that the results so far are a possible cure.  Its an overreach of the data. There are a lot of people out there with hopes and dreams around the Cword so caution is needed.  In the study six men with HIV had their blood filtered to remove a small percentage of their Tcells. The genesnipping compound was added in the lab and about onefourth of the cells were successfully modified. The cells were mixed with growth factors to make them multiply and then infused back into the patients.  Three men received about . billion modified cells. Three others received about  billion.  Three months later five men had three times the number of modified cells expected. As much as  percent of their total Tcells appear to be the new type  resistant to HIV Lalezari said.  The sixth man also had modified cells but fewer than expected. In all six patients the antiHIV cells were thriving nearly a year after infusion even in tissues that can hide HIV when it cant be detected in blood.  The cells are engrafting  theyre staying in the bloodstream theyre expanding over time said Lalezari who has no personal financial ties to Sangamo the studys sponsor.  The only side effect was two days of flulike symptoms. It will take longer to determine safety but several AIDS experts said they were encouraged so far.  It is a huge step and a first for the field of genetics said John Rossi a researcher at City of Hope in Duarte Calif. where he and Zaia plan another study to test Sangamos approach. The idea is if you take away cells the virus can infect you can cure the disease.  On Wednesday Dr. Carl June a gene therapy expert at the University of Pennsylvania will report partial results from a second federally funded study of  people testing Sangamos product. He treated his first patient with it in July .  Many questions remain   People born without the CCR gene are generally healthy but will deleting it have unforeseen consequences   Will HIV find another way into cells Certain types of the virus can use a second protein receptor though this is less common and usually when AIDS is advanced. Sangamo is testing a similar approach aimed at that protein too.   How long will the modified cells last Will more be needed every few years   Could doctors just infuse Sangamos product rather than removing cells and modifying them in the lab   What might this cost  Sangamo spokeswoman Liz Wolffe said its too early in testing to guess but it would be a premierpriced therapy  in the neighborhood of Dendreon Corp.s new prostate cancer immune therapy Provenge  .  Yet AIDS drugs can cost  a year so this could still be costeffective especially if its a cure.  Jay Johnson  who works for Action AIDS an advocacy and service organization in Philadelphia had the treatment there in September.  My results are excellent he said. The overall goal is to not have to take medication and then hopefully lead maybe to a cure.  Matt Sharp  of suburban San Francisco also had the treatment in September.  I would trade anything to not have to take a handful of medications every day for the rest of my life and suffer all the consequences and side effects he said.  I may not live long enough to see the cure but I always hoped for a chance.    Online  AIDS informationhttp  andhttp"