Researchers across the U.S. have discovered a method to check the duplication of the commonest form of HIV virus at a crucial moment when the infection is just beginning to mature in the body.
The research has hinted at a possible new component of human immunity against HIV -1 that could also be a possible new approach for a HIV vaccine.
HIV -1 virus that is spread through bodily fluids targets the immune cells, called CD4 T cells by infecting and destroying them. Scientists have long been aware of Interleukin-21 (IL-21) – a substance yielded by CD4 T cells that usually serve as an effectual defense against the HIV virus. Besides, boosting the generation of antibodies to attack the HIV virus; IL-21 also stimulates the anti-viral action of those immune cells, which concentrate in destroying viruses like HIV-1.
However, the process of how IL-21 could influence the early periods of HIV-1 infection that encourages the virus to increase and spread ceaselessly, was still unclear.
The researcher team thus, carried out a couple of studies to unravel the effect of IL-21 on HIV-1 virus during the latter’s early stages. For this, they formed a culture from human tissues, chiefly of spleen and lymph node tissue and rendered them to IL-21 before introducing HIV-1. After 72 hours (3 days) the scientists found that the cultures with IL-21 had more than less than two-thirds of HIV virus than those, which didn’t receive the therapy.
The second representation examined IL-21 in mice after human stem cells were transplanted in them in order to produce a physiological atmosphere as familiar as possible to that in humans. They observed that the mice commenced yielding IL-21 over the span of two weeks, and the outcome stayed stable. After 14 days, more than half of the mice with IL-21 didn’t show noticeable level of HIV-1 as the substance reduced both the consequence as well as extent of the disease.
A scrutiny of the results projected that IL-21 not only fires up immune system right from the start, but also ceases the HIV-1 virus from duplicating during the crucial early stages of its development, when the virus is just focused on one area of the body and hasn’t yet spread throughout.
The decline in viral weight is caused due to the surge of episodes instigated by IL-21. The researcher team discovered that IL-21 commands CD4 T cells to multiply the amount of small RNA molecule known as “microRNA-29 (miR-29)” that hinders the duplication of HIV-1, checking the sum of virus generated from the infected cells.
Dr. Laurie H. Glimcher, the Stephen and Suzanne Weiss Dean of Weil Cornel Medical College and the senior author of the study said that the research underlines elements of the human system, which are “capable of mounting an antiviral response and driving intrinsic resistance to HIV-1.”
Dr. Stanley Adoro, a postdoctoral associate in medicine in Glimcher’s lab and the lead author of the study said that the research has revealed a “potentially potent arsenal that patients have against the virus,” and believed that “IL-21 is one of those arsenals and that deploying it early will be powerful” in combating the infection.
However, he added as HIV-1 that is infamous for damaging IL-21 generation in patients and stopping miR-29 extraction in CD4 T cells, their “goal now is to fully understand the nature of the IL-21 response in the first few days after exposure at the site of virus entry and how HIV-1 reduces miR-29 amounts in target CD4 T cells.”
This discovery also throws light at a possible proposition for a HIV-vaccine. Although, scientists are still arguing the elements of a future vaccine, there is an agreement that ceasing the HIV-1 virus at its earliest and most susceptible stage would be the most effectual approach to sheltering the patients from the disease.
Dr.Glimcher said that their research has projected that IL-21 response could be stimulated at the early periods of the infection, and “in addition to what the vaccine will do later down the road, could potentially limit the initial levels of virus in the body.”
She added, “We are hopeful that this knowledge will bring us one step closer to shielding patients from this deadly and complex virus.”
The research team included scientists from Weil Cornel Medical College, Harvard University, the Ragon Institute of Massachusetts General Hospital and Masachusetts Institute of Technology.
The study was published on June 25, in a journal called Nature Communications.
On the prospect of HIV vaccine, in our earlier article it was reported that Weil Cornel Medical College along with the Rockefeller University, the Scripps Research Institute and International AIDS vaccine initiative, discovered through an experiment that orderly immunizations adapted with different stages of immune response could generate a special group of antibodies, known as “neutralizing antibodies” that contains the ability to attach themselves with the HIV virus and neutralize them as they mutate in a patient.
Pia Dosenovic who is a postdoctoral fellow in Michel Nussenzweig’s Laboratory of Molecular Immunology at Rockefeller University and the co-author of the experiment stressed on the fact that although the outcome of their experiments show that orderly immunizations might vaccinate againt HIV, they have “only just begun to understand how this sequence would work.”
This study was published in a journal called Cell and Science.