Can a person with a compromised immune system develop a response to a cancer vaccine?

Can a person with a compromised immune system develop a response to a cancer vaccine? Yeah, so that's a great question and that's one of the hurdles in cancer vaccines, which is we know that we can make vaccines against smallpox in a patient who's got a good immune system and that has, you know, protected the world from what was a major source of mortality. The question is can you recapitulate that with a tumor where the cell is more similar to a normal cell than a bacteria and can you do it in a person where the immune system isn't working so well? That's where we hope that a combination of the right kind of adjuvants, so a dendritic cell for instance, maybe being a better teacher, more powerful and other factors that can help mold and shape the immune system of a patient or reverse some of the things that the cancer those combinatorial things we think we hope will bear fruit rather than the single approach. And I should just mention as an example of how that can work, the way a CAR T cell is constructed is that the stimulatory molecule is inserted next to where the CAR T binds. The first generation of CAR T cells didn't have the stimulatory molecule, they didn't know they had to do that and they didn't work. So we think that this is about the devil is in the details that by creating better stimulation adding those extra components, understanding what in the patient, in the cancer patient's immune system turns responses off and blocking those things, putting those pieces together we hope will lead to a long term immune protection. Are there any challenges with cancer vaccines? I think the first simple thing to say about vaccines is they don't work well enough yet. For all the reasons that you asked, the patient's immune system not working well, knowing what the right antigens are, getting them presented in the right way. That's what all the research is very much in the middle of trying to understand. And I see that the real challenge is in some ways patience to know that you're working in a way that hopefully will bring fruit but to make sure you're taking into account all those other pieces and having the patients to kind of actually address them. I think the other important thing to say is that some of the tremendous successes we've seen with the immune system so far have still progress to be made in them. It's amazing that we see responses to cars. We know that most patients relapse and so we have to address that. And so we think that fixing the immune system, understanding ways that the immune system gets tired and we think vaccines are a very important way to do that may bring us to a better place.