“What became clear was dendritic cells orchestrate immunity, so they are the center of the immune response.”

Sarah Schlesinger: What became clear was dendritic cells orchestrate immunity, so they are the center of the immune response. They pick up any foreign material, whether it be a bacteria, whether it be pollen to which you’re allergic. Probably most of them spend their time picking up your own self, showing those antigens to the rest of the body. They pick up the antigens. They process it, which means they sort of chew it up, and then they display it on their surface with several other molecules. And that display allows the T-cell lymphocytes and the B-cell lymphocytes to see the antigen. So the only way that a lymphocyte can respond to an antigen is if a dendritic cell processes it and shows it to it.

So because of this concept, it became clear that to make a vaccine work, you need to get to a dendritic cell. In all likelihood, more than in all likelihood, almost with certainty, all vaccines that work, work by getting to dendritic cells. We just don’t know how. So since we have been working on HIV vaccines, well, now for 25 years, but then for 15 or whatever, and the regular, the sort of empiric methods that had been tried before were not working, the notion that one should engage in rational vaccine design, and directly target dendritic cells, began to gain favor. And so I began to work on that end of vaccine design at the Walter Reed.

Recorded on: June 10, 2008