At present, only two people have validly cured of HIV — the so-called “Berlin” and “London” patients. Another “Dusseldorf patient” is in remission for 17 months and is considered a good candidate for the title of the third recovered.
In all these cases, the doctors applied the same technology — a bone marrow transplant from a donor with a mutation in the gene for CCR5. The CCR5 receptor needed for the virus to penetrate the cells of the immune system, and mutation hinders this process and makes the carrier resistant to the infection. Such radical treatment is not safe and can only be applied in individual cases. The indication for a complete “reinstall” of the immune system, which, in fact, is a bone marrow transplant, may be lymphoma. The patient “deinstalliert” his personal immune system along with the cancer cells and instead re-infusing the stem cells of the bone marrow donor, which restores myeloid and b cells.
For transplantation should carefully select the donor: it must have the necessary and relatively rare mutation in CCR5, to be histochemistry and not hurt anything dangerous for the recipient. Even under these rules of transplantation remains a risky procedure — much more dangerous than conventional antiretroviral therapy — and could fail. So, in two patients from Boston after they have undergone transplantation and had stopped taking antiretroviral drugs, HIV re – appeared in the body after 12 and 32 weeks, respectively. In addition, a mutation in the CCR5 only works with a certain type of HIV and does not help with the rest.
A new case is fundamentally different from all listed the fact that “são Paulo” patient didn’t have cancer of the blood and bone marrow transplantation he did. Instead, he and four other volunteers have received particularly aggressive cocktail of drugs. In addition to the three drugs which they took at that time (tenofovir, emtricitabine and efavirenz, different blocking viral reverse transcriptase), it included two more drugs — dolutegravir and maraviroc. The first prevents viral sequences integrated into the human genome, and the second binds to CCR5 and prevents HIV to enter the cell. The idea of researchers that this combination — similar to the comprehensive treatment of antibiotics — was supposed to help impose the pathogen from all sides and not let him slip away.
On top of this, patients prescribed nicotinamide (or vitamin B3), which in theory has immunomodulatory effects. At the end of June in the journal Brazilian Journal of Infectious Diseases published an article Brazilian-American authors in which they demonstrated the ability of this substance ex vivo to activate HIV holed up in long-lived T-cell memory.
Cycle of HIV
As media HIV uses RNA. When the virus enters the cell its RNA the cellular machinery synthesizes enzymes, which are already in the matrix, the cellular RNA is synthesized viral DNA integrates into the genome of the cell. There it begins the normal synthesis of RNA and proteins that are packaged in virions and is ready to leave the cage.
Even if you completely block the activity of HIV with antiretroviral therapy, “silent” DNA integrated into the genome, is still preserved, and after the medication is discontinued the virus becomes activated again and again begin to multiply. In such a depressed state, the virus may be years and neither the immune system nor the medicines are not able to detect and destroy.