Vaccine induction of CD4-mimicking HIV-1 broadly neutralizing antibody precursors in macaques. (https://pubmed.ncbi.nlm.nih.gov/38181743/)

These scientists wanted to find a way to make a vaccine that can protect against HIV, which is a virus that can make people sick. They knew that there is a part of the HIV virus called the CD4-binding site (CD4bs) that can be targeted by special antibodies called broadly neutralizing antibodies (bnAbs) that can protect the body from getting infected.

But, so far, the vaccines that have been made for HIV have not been able to make these bnAbs. There are a few reasons why this is difficult. One reason is that the CD4bs is covered by something called glycans, which makes it hard for the vaccine to target it. Another reason is that the body needs to have the right kind of immune cells, called B cells, that can recognize the CD4bs and make the bnAbs. And finally, the vaccine needs to encourage these B cells to change and become stronger.

So, in this study, the scientists tried something new. They gave a vaccine to monkeys called macaques that was designed to target the CD4bs. And guess what? The vaccine worked! It made the macaques produce antibodies that were similar to the bnAbs that can protect against HIV.

The scientists looked at the structure and genes of these antibodies and found that they were similar to the bnAbs that can mimic a part of our body called CD4, which the HIV virus uses to enter our cells. This is important because all the bnAbs that can mimic CD4 have something in common when they bind to the virus.

The genes of these macaque antibodies were also similar to the genes of human antibodies that can protect against HIV. This means that the macaques have immune cells that are similar to ours and can make the same kind of protective antibodies.

This study is a big step forward in finding a way to make an effective vaccine against HIV. It showed that the vaccine can trigger the right kind of immune cells to make the right kind of antibodies that can protect against the virus.

Saunders KO., Counts J., Thakur B., Stalls V., Edwards R., Manne K., Lu X., Mansouri K., Chen Y., Parks R., Barr M., Sutherland L., Bal J., Havill N., Chen H., Machiele E., Jamieson N., Hora B., Kopp M., Janowska K., Anasti K., Jiang C., Van Itallie E., Venkatayogi S., Eaton A., Henderson R., Barbosa C., Alam SM., Santra S., Weissman D., Moody MA., Cain DW., Tam YK., Lewis M., Williams WB., Wiehe K., Montefiori DC., Acharya P., Haynes BF. Vaccine induction of CD4-mimicking HIV-1 broadly neutralizing antibody precursors in macaques. Cell. 2024 Jan 4;187(1):79-94.e24. doi: 10.1016/j.cell.2023.12.002.