Human immunodeficiency virus (HIV) is a viral infection that attacks our immune systems. Infection enters the body by contact with bodily fluids, such a blood and semen. The disease can be transmitted through anal or vagina sex, and/or sharing needles and other drug injection equipment. Once the virus enters the body, it targets specialized immune cells known as T cells. These cells are critical for an effective immune response. T cells are responsible for identifying and targeting invading pathogens. They also help stimulate other immune cells to elicit robust immunity. HIV will take over the cell’s genome and begin producing more HIV, consequently destroying the T cell. As HIV replicates, T cell number declines and makes it more difficult for the body to resist disease. If HIV progresses without early intervention, it can lead to acquired immunodeficiency syndrome (AIDS), which states that the T cell count in the blood is below 200 cells/mL. It is important for individuals with increased risk of disease to talk to their doctor about ways to prevent or treat early symptoms of HIV before it progresses.
There is no cure for HIV, but there are many treatments that delay progression and control symptoms. Antiretroviral therapy (ART) is a common form of medication that works to suppress the replication of HIV in T cells. It is best to get on treatment as soon as possible to prevent progression to AIDS. While treatments are limited, individuals can still work to prevent contracting HIV by engaging in protective sex with condoms, never sharing needles or syringes, and using pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP). PrEP and PEP are medications that individuals with high risk of HIV take to prevent disease contraction. The treatment blocks an enzyme in the cells to stop the virus from replicating. Patients take PrEP daily as a pill or can get injections. While there are many preventative options and treatments that limit disease progression, millions of individuals live with HIV and over a million contract HIV each year. In response, scientists are trying to find better ways to target HIV after exposure.
A recent paper in Nature Immunology, by Dr. Florian Klein and others, discovered an antibody that can target various forms of HIV, improving treatment efficacy. Klein is a Professor and Director of the Institute of Virology at the University of Cologne. His work focuses on HIV and how to better target the virus by developing antibodies.
Klein and his team identified an antibody referred to as “CD4bs bNAb”, which neutralizes various forms of HIV. This is a major finding since HIV changes and evolves constantly. Consequently, finding an optimal therapy is a challenge.
Researchers examined blood samples from patients that have effective immune systems against the virus and developed over 800 different antibodies based on the results of these samples. After characterizing each antibody, scientists found one that targeted multiple variants of HIV. Not only does CD4bs bNAb maintain a broad range of targets, but also overcomes resistant mechanisms that have previously made other therapies ineffective. To explain the antibody’s precision and efficacy, researchers analyzed the structure and found that it has a long amino acid chain that can reach viral targets that are often difficult to access. Klein and his team suspect this long chain is what makes the antibody so potent.
Klein and others have developed a robust antibody treatment for patients with HIV. As a result, it is predicted that a single administration could provide 93% protection in clinical applications, based on computational analyses. This is a groundbreaking discovery because of the antibody’s ability to target various forms of HIV and overcome resistance. Overall, this has translational potential in the clinic by improving preventative medication and providing effective treatment in patients with HIV.
Paper, Nature Immunology, Florian Klein, University of Cologne
