What are natural killer cells? What is their job? How do they differ from t-cells?

What are natural killer cells? What is their job? How do they differ from T cells? Natural killer cells are part of our innate immune system, and by that I mean that they're a cell population that doesn't require any education. So you may have heard of T and B cells, which are another part of our immune system. But those actually learn different pathogens or different bugs that we come into contact with or maybe even different tumors by having some genetic recombination in their actual DNA.

And that's why we talk about memory cells, memory B cells and memory T cells. But for natural killer cells, they really work on identifying different things that are not normal. For example, a virus or bacteria based on a couple of ways. One, they work with antibodies. So if you have an antibody that comes up because maybe you were sick and you develop antibodies or if you get an antibody like for example, daratumumab, which is anti cd38 antibody, the natural killer cell then knows to bind to a portion of that antibody.

So the antibody becomes a link, meaning the antibody binds to the cell. And the other part of the antibody binds to the natural killer cell. And it can then elicit toxins and kill directly that cell. So that's why we use natural killer cells, as are we think of them as sort of our effector cells, the ones that do the business for things like daratumumab.

So they don't need training and education by being exposed to different things before, but they work with things like antibodies. Another thing that natural killer cells do is potentially recognize abnormal cells because they look at something called class one protein. And without going into too much detail, the short of it is that cancer cells often hide that protein to evade immune activity from things like T cells.

But ironically, natural killer cells can sometimes see that and think, Hey, this is not myself, and they can actually kill it without, again, any genetic recombination. So we know that these cells are, as I said, part of the innate immune system as opposed to what we call the adaptive immune system, which is something, like I said, that might require genetic recombination.

Now we know that natural killer cells are a very effective therapy or have effective therapy potential, and we're hoping to try to develop that more in multiple myeloma natural killer cells is a type of white cell that we have in, you know, in our body that goes after viruses, after cancers. Its job is to protect our bodies from those viruses or for cancers, for that matter.

They are a type of lymphocyte. They're a little bit more maybe a little more primitive in in developmental biology in that they they're part of what's called the innate immune system rather than the adaptive immune system. The adaptive refers to sort of T cells and B cells, B cells making antibodies, T cells expressing T cell receptors that allow them to target specific markers on cells, whether it be cancer cells or infected cells, natural killer cells that don't have t cell receptors.

They have other surface markers that that enable them to, you know, interact with abnormal cells, whether it be cancer cells or infected cells in the body. But but it's not it's sort of specific to a particular target or a particular molecule or piece of a molecule. Their functionality and ability to recognize and kill abnormal cells is a little less specific, which can be advantageous, especially in the early goings of of an infection, for example.

You know, it takes time for the body's adaptive immune system to respond to the infection, and natural killer cells may be able to get something going early on. So they have distinct, you know, functional properties that may make them, you know, to be even potentially even better or or certainly different types of immune cell for cellular immunotherapy. And natural killer cells were discovered at Karolinska Institute in the seventies.

They are very few cells, about 2 to 3% of all white blood cells. We all have it as people, and their main function is to act against viruses. But even against tumors, you know, you probably get scared when I tell you that even small kids, even your kids can get tumors and that natural killer cells accumulate at the tumor and destroy it.

Before growing up to cancer. Are there different types of NK cells? The interesting thing about NK cells is that there are a lot of subtypes and they are differentiated by how much they express certain things like CD 56 or CD 16. These are just markers on the surface of these cells and they sort of give an idea about immature and mature and K cells.

And actually what we are now learning is that there are subsets that might be memory in case cells. They may be more likely to respond to certain pathogens or certain bacteria or viruses. And then we have in case cells that might be bone marrow based versus peripheral blood based, and they may have different ways of interacting with tumor cells.

So we do have this knowledge of subsets of NK cells. I would say that characterizing them like helper T cells or CD8 killer T cells or memory T cells, we haven't gotten as far as we have in T cell biology. How does car NK cell therapy compared to CAR-T cell therapy? It's as easy as natural killer. That's the name.

So you're going you put your bullet and you're out. So it's immediate, very effective effect, probably without side effects, but not long lasting. The T cells are on the opposite way. People want to use the T, so the people that want to use the T cells and they want to use them because they think they they will be long lasting in your body and they will act against the cancer cells under a longer time.

That's the main difference. Probably causing side effects such as the CRS, cytokine release syndrome. So it's a direct immediate effect and away from full place or slowly, not slowly, but but somewhat slower than the NK cells effect and long lasting in your body. If you ask a T cells guy or woman and the NK cells guy or woman, they will put handed argument for and against, but probably not because the NK cells are t cells. they have markers that differentiate them from the T cells.

But I mean it's a it's the most advanced T cell I would say as the plasma cells are the most mature B cells, the NK cells are the most advanced t cell