Some time ago, I made a post (actually two) about the innate immune system where I briefly explained the function of Natural Killer Cells (NKs).
@kryzsec also made a post that contains a paragraph about these cells, that play an important part in our immune reaction.
Because of this, I won't go into too much detail about them. Instead, I will show you some fun gifs of what we did in the lab yesterday!
We were interested in the killing behavior of NKs, as there are two ways in which they can kill other cells.
The first step is the same, they come in contact with a potentially "bad" cell and check for certain structures on the surface. These structures either inhibit the killing reaction or encourage it.
After that, they either connect to a receptor at the target cell, which causes a cascade of reactions that lead to the cell's death, or they set free a number of granules, which contain enzymes that also lead to death. The second way is faster, but it's not 100% clear how the NK chooses which way is the appropriate one.
For our experiment, we used a "Jurkat" cell line, which was T-lymphocytes that are missing the MHC-I, a for the immune reaction important complex at the outside of the cell.
The NKs came from the "waste" that is created when cleaning donated blood. There are several steps required to separate them from everything else, but we didn't do that ourselves.
The Jurkat cells and NKs were both dyed with different fluorescent dyes, green for the Jurkat cells (which dyed the cytoplasm) and red for the NKs (here the granules collected the dye). They were then measured with a fluorescence microscope over the course of an hour, the microscope took a picture every 20 seconds.@suesa
After analyzing the results, I was able to create these gifs:
Here you can see a NK swim past a Jurkat cell, then come back to attack and kill it. Note the rapid loss of green color! It means the cell is leaking. There's also a faint red invading the cell, which suggests that granules were used in the killing process.
This NK seems to be killing two Jurkat cells at the same time. See how it pushes between them and they both start losing color? Again, they're leaking.
My last NK didn't kill one, not two but three Jurkat cells during the hour it was observed. It seems to linger a bit after killing the first one, but then rushes towards the others.
I like how well you can see the fact that NKs aren't just tiny balls the whole time, as it stretches out at the end. One tends to imagine cells as something stationary or controlled by, for example, the currents of blood. But these NKs move very much by themselves!
Seems like killing others is in our blood !! Lol 😂
I'm glad I wasn't drinking anything as I might have spit it all over my laptop as a reaction
bereh
Hehehe :p
At least when we go to jail for murder we'll have a cell mate...
OH GAWD! STAHP! I am drinking and this computer is expensive!
Never drink while reading comments!
Sounds advice; is sound.
LOL!!!!
Honestly i didnt understand half of the article because im not that much familiar with doctory staff :D but the gifs were great, they showed how cells were destroyed by the touch of those NYs! Thank you
Tbh, I mainly wanted to post the gifs because I love how they look. The other info is just pretty decoration.
Not only decoration, atleast we know what these gifs are about!
According to the gif, it took almost 30mins or is that secs to kill one and make the colour fade.. Wow.
Yes! The NKs actually need a while to kill
I must say that I completely agree with your last statement
Honestly I had never watched a NK cell directly and seeing it was just, amazing and enlightening. Like, wow. Sorry I do not mean to have a spammy: "good post" kind of comment but I am just sitting here watching this and just, I am mesmerized by seeing it in action. Though now I have a lot of curiosity surrounding how the NK cells choses to kill, I know you stated we do not know, 100%, how it chooses but its just sparked curiosity in me now. So my question I will ask, if you are willing and have the time to answer, is what is the current leading hypothesis or model on how we think it does this? If you know.
You don't need to answer, I will probably start searching it up to see the ideas floating around but... those GIF's.
"Good post Suesa!"
My supervisor said "we have no idea. One is faster, so that might be a factor. Maybe it uses the receptor pathway when it runs out of granules. But that's just speculation".
And I agree with you in the gifs. When I was scrolling through the pictures, I just knew I needed a gif of it.
it is like an angel of death, if it touches you, you are dead. If I am not mistaken jurkat is an immortalized T lymphocite, it is my first time to see it on action.
It is! You are not mistaken.
Hello @suesa!
I read the post you referred and it was very interesting (you even gave me extra information about the cells in one of the comments I wrote to you, I'm still grateful for the answer), but being honest with you, when I saw the gifs I could only exclaim: WTF!
Hahahahaha I'm sorry, but seeing those little things acting in such a way is really amazing! I have seen similar experiments in movies or TV series, but never from a real person.
I don't understand much about the cell world, but the way you explain it seems great to me! With you I'm less and less ignorant of the subject, I thank you for that.
I will wait for more of these small particulars of microscopic life
As I haven't read the other posts, permit me to ask the reason behind the NK killing the Jurkat cell.
The absence of MHC-I at the outside of the Jurkat cell acts as a signal that something is wrong with it. Normally, MHC-I binds to a receptor of the NK and inhibits killing. It's just one of many, many signals but an easy one to use in this scenario.
Ok. Now it's clearer. Thought it was just a homicidal cell with a weird thirst for killing.
I like the Nuclear Extracellular Trap (NET) ability of NK cells too, it's like they go all Kamikaze at the end...such a bad-ass innate immune cell!!
I never saw anything like this. Just Wow!!! So you are saying that they check for certain kinds of surface markers and kill them. Right?
Yes! There are a lot of possible markers that inhibit or encourage the killing, the absence of MHC-I is one.
This feels like watching a bloodbath. However lucky these cells do not contain blood, but still it looks brutal.
This is also the very specific kind of content we should see more on Steemit. You are giving things which regular people like us can rarely get to see.
On the next episode, we will see Unnatural killers, as we introduce a bullet which kills far more cells in an hour.
We need to extend the reach of science more if we want to combat the pseudoscience fans around Steemit. The first article in science tag is a pseudoscience article about how vaccines harm people.
Your article rocks, may there be more like it! Thanks!
The cellular world is an entire universe and understanding its creatures and their interactions seems a very complex job. I want to appreciate the way you put a lot of effort to convey these difficult topics in an easy way. This is for sure The Science Blog.
I loved this one... microscopic murder, some gore in the blood :D
This is really neat stuff, @suesa. I learned about cells in biology class and I knew they were "alive," obviously... but I never really paid attention to them. Every now and then I realise they exist, and I'm made up of them.
I also never realised their activity could be this animated-- as you said, I think of cells and imagine them as mostly either stationary or moving along in the bloodstream. Instead, those are real, tiny things committing genocide of sorts on other tiny things... inside me! I can't think about it for too long or I'll go crazy.
Thanks for teaching me something new today. Your science posts are one of my favourite things on Steemit.
So violent!! Thanks for this post, I love a good science article. Thank you for taking the time to create quality content for us to read :)
good !!
By the body reaction produces antibodies and fight to protect us from the attack and how long can?
Great
Such a meaningless comment
This No seem pretty destructive, these cells are really damaged, and from the gif, it seems Nk has completely taken over in the last gif
yes! this is natural killers. i see the natural killers at the first time. and it is informative for us.
Wow that is scary. It is like little animals killing eachother.
Great you always come back with new informative post you great keep it up
As a student, I always found immunology very intruiguing... Thanks for the nice reminder ;-)
Anything other than literature aint my way....but my instinct says this is a nice post
Maybe you're more interested in my fictions ^^
Obviously
I try to keep a balance and post both. Many people follow me for both :)
Its amazing to see people post on both...you are such a rare gem
Amazing
Nice gifs @suesa, but did you test how aluminium and thimerosal affect the NK's killing abilities? :D
.... :P
I don't mean to ask here but there is no other means. I'd like you to give me a reference where I can read about these. I like the concept but I understand it not.
https://www.ncbi.nlm.nih.gov/pubmed/?term=natural+killer+cells
Thanks ma'm
Useful information.
Nice illustration !!! :D Really lovely gif
Chemical biology XDD yeah !!
btw is there some localization for the red dye?
Not sure what you mean? The granules take up the dye, because their interior is relatively acidic, while the dye is slightly basic.
Actually I am not too sure what is granules (I thought granules is small particulates? but you said it is something with enzyme?)
Sounds like lysosome ? or it is not an organelle
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2116378/
Haha i see~
Still got a long way for me to learn biology lol
omg Thanks for sharing
Some bloody killer...
:o So coool!
Hearing about NK cells in microbiology class is totally different than watching them actually kill other cells
Thanks for the gifs @suesa
The more I learn about biology, the more I'm amazed that all these tiny parts can work together and keep up alive at all. We imagine that we're thinking, independent people, but we're more like massive colonies held together by a bag of skin and good intentions.
The gifs are amazing. They look like something out of a video game. That NK cell moves around with such speed and agency, it's hard to imagine it's not a thinking creature with its own brain.
Remember, this happened over the span of an hour. It moves a lot slower in reality!
But I agree, it's absolutely fascinating.
Hy, super
Nice post
Nice Spam
you create a great post....and you write a important topic...i like it.... hope everybody like your post...thanks for shear it...
Generic Spam Comments for the Win!
According to the gif, it took almost 30mins or is that secs to kill one and make the colour fade
Did you seriously copy @sweetestglo-eu 's comment and expect me not to notice?
:))