can prevent The outbreak of immunodeficiency disease, Aids, Doctors today with drugs, the multiplication of the Human immunodeficiency Virus (HIV). This anti-retro viral therapy (ART), Aids is fatal. But to free a HIV-Infected of the virus and the cocktail of Drugs, the Doctors have managed to once – over ten years ago in Berlin. Now there is a second patients in London, this is the first Tests, probably also managed.
Better than winning the lottery
Aids virus, a slip need the hole to be able to in the human cells. It is called CCR5, and sits on the surface of certain immune cells, the T-cells. In about one percent of the population in Europe, this loophole is missing, you have a Mutation in the CCR5 gene are largely resistant to HIV infection. So why not the blood and immune cells to image stem cells in the bone marrow against CCR5-mutated stem cells to replace, so the Aids viruses infect the cells of the Infected and also not able to reproduce? This idea circulated among Aids experts, since they knew of the CCR5 Mutation. But no one runs a bone marrow transplant to people who are basically healthy, because you can prevent the onset of Aids with a cocktail of Drugs. Unless the HIV-Infected is so seriously ill with cancer of the blood that his only Chance is such a bone marrow transplant. This was the case in 2008 in the case of Timothy Ray Brown. The Americans lived in Berlin and was treated at the Charité hospital of the doctor, Gero Hütter. It is not due to visit for Brown, only a donor with a matching tissue type for the stem cell transplant, but the stem cells lacked, moreover, the CCR5-loophole. A hit with a probability similar to that of a lottery prize. And indeed, The weakened Brown died at the time of Transplantation, although almost recovered, but then was able to sell its HIV-suppressive medications. In his blood is no Aids virus can be detected until today. Since then, the “Berlin Patient” is the first of a HIV-infection, and healed people.
In the scientific magazine “Nature” (study starting Tuesday, January 21, o’clock, public) describe researchers are now in the case of a HIV-Infected in London, developed in 2012, lymphatic gland cancer (Hodgkin’s lymphoma) and with a CCR5-mutated bone marrow stem cells was treated by a team of Doctors from the University College and the Imperial College London and the University of Cambridge and the University of Oxford. 16 months later, the Doctors continued the anti-retroviral drugs because Aids viruses in the blood were detectable. Also 18 months later, the diagnosis is nothing, the Patient is apparently free of HIV even though the team of Doctors headed by Ravindra Gupta stresses that it is “too early” to talk of a “cure”. The “Mississippi Baby”, that should be before and after the birth with an intensive anti-retroviral therapy prior to virus transmission from the infected mother protected, had a total of 27 months after the end of therapy, no detectable amount of virus, then the Virus in 2014 occurred again.
A healing therapy of the HIV infection is not yet in sight
Too soon, even it would be incorrect to claim that a curative therapy is available, HIV-Infected could be freed of the virus, are not diagnosed with blood or lymph node cancer in Germany alone, approximately 86000 people. Because bone marrow transplantation is only considered in case of emergency, as a last resort, and comes with basically a Healthy person in question. For good reason, explains Gero Hütter, had treated in 2008, the “Berlin patient”: “Since the successful Transplantation of the ‘Berlin patient’ is trying to reproduce this case,” says Hütter, today, the medical Director of the company Cellex in Dresden. “Unfortunately, some of the patients who had received the same treatment have died early of complications or relapse of their cancer.”
In most cases, no donor with a CCR5 Mutation, whose tissue type matches the patient. “The stem cell transplant will remain in the future, HIV patients with additional hematologic disorders.” Nevertheless, the “London Patient indicates that” the fact that the successful treatment of the “Berlin patient” was caused not by chance or by special properties of brown. “This new successful case tends to indicate that it is the result of the selection of the Graft, which yielded no points of attack for HIV, to this healing,” says Hütter. “Thus the development of gene therapeutic therapy strengthening options in order to develop a method, this principle of the HIV-cure practical and for the patient less risky to implement.“
The success of London gives hope for gene therapy approaches
Thus, Hütter plays on Experiments in which HIV-Infected immune cells taken from the laboratory and genetically modified. Gene, the CCR5 cut more this-Gen so precise that the resistant do will be imitated at the end of Mutation (called Delta32). The altered cells are multiplied and the patient is injected back. Tests have shown that in recent years, and that these cells survive in the body and are resistant to HIV infection are able to build a functioning immune system. “Patients would prefer to be healed, to swallow as every day medicine,” says Carl June, cancer – and HIV-researchers at the University of Pennsylvania in Philadelphia, has been made in 2010 as the first such gene therapy Experiments, together with the Californian biotech company Sangamo. “Scientifically, we’re ready,” said June to the daily mirror. “If we change both stem cells and T-cells and the combine, we can build up in the patient’s immune system in which HIV is unable to reproduce.” Because in order to have a lasting effect, you must have the CCR5 Mutation, not only in Mature and finally viable T-cells, but also in the genome of the blood – and immune cell-forming stem cells induce. Only then are always HIV-resistant formed immune cells.
in fact, a study at the City of Hope National Medical Center in Duarte, California, with the help of the stem cell change to a twelve-HIV-patients is tested running for 2015. The amount of virus in the patients nine to twelve months after the Infusion of the genetically supposed to be souped-up stem cells, no virus detected, is to be interrupted, the retroviral therapy. Results of the study will be submitted in March 2019. June is testing an approach in which both the “Offensive”, a better immune system against the already HIV-infected cells, as well as the “Defensive” protection against reinfection with the virus by the CCR5 Mutation, should be strengthened. “We are currently preparing a Phase I study with 12 patients, where we produce two different cell types – better killer cells to HIV-to get rid of infected cells, and immune cells, which are CCR5-mutated.” Other researchers are trying stem cells from the umbilical cord of newborn babies are genetically engineered to adapt and use for the treatment of HIV patients. They could be provided provided – success – in sufficient number and with a matching tissue type. Thus, the tedious and time would be necessary to perform time-consuming sampling and genetic adaptation of cells of each of the HIV patients.
Ten years up to the clinic
However, not everyone is convinced by the gene therapy approach. That would probably achieve even in the best case, only a part of the stem cells, and can change, says Hans-Georg Kräusslich, Director of the Department of Virology at the University hospital of Heidelberg: “Currently is not, therefore, expect that as a result, equivalent success will be achieved” as with the “Berlin” or “London” patients. Anyway, the two cases were quite different. Although both diseases that require a transplant, but unlike Brown could be dispensed with irradiation of the body before the transplant, says Kräusslich. “In addition, the ‘Berlin Patient had a relapse of the leukemia after the first Transplantation, and needed a second transplant, again with irradiation of the whole body.” Even if both patients are now free of HIV and remain open as to whether the left is alone, CCR5 Mutation, on the loophole, or whether the transplant has other effects on the virus. Both patients had a “Graft-versus-Host”reaction, in which the bone marrow and the immune cells of the donor attack the cells of the body of the patient. Also cancer cells, and presumably also virus be attacked infected cells. It is not excluded that also play a role in the healing, says
Jürgen Rockstroh, senior physician and head of infectious diseases at the University hospital of Bonn.
More about
world-Aids-day, The locked Virus
Sascha Karberg
says To gene therapy in the clinic, the HIV-Infected can heal, it’ll take ten years, even June. The question of whether such a cheap therapy is also worth it, answered in June with Numbers I Will be infected someone in their early twenties and a life-long retroviral drugs and other therapies, provides, cost around a Million dollars per Patient. And in the United States alone there are currently a Million patients, provide. (smc)
