Molecular binding of antibody 04_A06 to the HIV-1 surface protein (gray). Different domains of the antibody are represented by different shades of blue. Image: Uniklinik Köln/Lutz Gieselmann.
An international team of scientists led by the German Center for Infection Research (DZIF) at the University of Cologne has recently identified an antibody capable of neutralizing the human immunodeficiency virus HIV-1 in almost all tested variants, potentially opening new avenues for treatment and prevention.
According to DZIF, the antibody, designated "04_A06", demonstrated remarkable effectiveness in laboratory tests, neutralizing 98.5 percent of more than 300 HIV strains. Experiments in humanised mice – whose immune systems have been modified to resemble those of humans – showed that "04_A06" could reduce viral loads to undetectable levels. Most other HIV antibodies only provide short-term effects in such models, as the virus quickly develops resistance.
Antibodies are proteins produced by the immune system to specifically target pathogens, but HIV's high mutation rate has made it difficult to identify broadly effective antibodies.
The research team studied blood samples from elite neutralizers – individuals whose immune systems naturally control the virus more effectively than usual. From over 5,000 B lymphocytes, the scientists generated more than 800 antibodies and tested their efficacy, with "04_A06" emerging as the most potent and broad-acting.
Dr Lutz Gieselmann, physician scientist at the Institute of Virology and first author of the study published in Nature Immunology, said the antibody's ability to overcome classic viral resistance mechanisms could make it a promising candidate for future clinical use.
Structural analysis revealed that "04_A06" possesses an unusually long amino acid chain, allowing it to reach conserved areas of the virus that are difficult to mutate without impairing function. This feature may explain why it retains activity against variants that evade other antibodies, according to DZIF.
Computer modelling further suggested that a single administration of "04_A06" could offer more than 93 percent protection in potential clinical applications. The antibody has been exclusively licensed to Vir Biotechnology, Inc., with researchers highlighting its potential both as a treatment for people living with HIV and as a preventive measure for those at high risk of infection, as per DZIF.
