T Cell Receptor Activation

Now that we know about T and B-cell development, let's learn about T cell receptor activation. Only certain T cells are allowed to differentiate into mature T cells, whether CD4+ or CD8+. How does this work? Let's find out!

Script by Niyati Vachharajani

Check out "Is This Wi-Fi Organic?", my book on disarming pseudoscience!

[mangogo]

Hey Professor Dave. I was just wondering at 4:31, your diagram had MHCI binding to CD4 T cells, and MHCII binding to CD8 Tcells. Shouldn't it be the other way around?

[RiyadhSaleh-go]

4:29 MHC II binds with CD4+
MHC I binds with CD8+

[hardoise]

You're one of the few with whom I can allow myself to tell people "No guys, there's good on youtube"

[FrogUniverse]

4:35 The image on the left should show a T cell labeled as CD8, not CD4. CD8 is the co-receptor that interacts with MHC class I molecules, which are presented by nucleated cells. CD4, on the other hand, interacts with MHC class II molecules, which are presented by antigen-presenting cells (APCs). It looks like there was a labeling error in the diagram. 4:42 there is a labeling error in this image as well. The diagram shows CD4 pointing to MHC I and CD8 pointing to MHC II, which is incorrect. The correct associations are:
CD4 should be pointing to MHC II.
CD8 should be pointing to MHC I.
This is because CD4+ T cells (helper T cells) interact with MHC class II molecules, while CD8+ T cells (cytotoxic T cells) interact with MHC class I molecules. 5:00 As you can see here the top diagram contradicts the bottom. labeling in the bottom image is correct. Here’s a brief overview:
CD4+ T-cell interacts with the MHC II complex on a macrophage.
CD8+ T-cell interacts with the MHC I complex on an infected cell or cancer cell.

[matreyia]

wow… not a medical student but now understand the mechanisms behind immune system cellular processes. thanks 🙏

[TheCrossroads]

FYI the schematic @4:36 has CD4 and CD8 flipped

[universeusa]

Thanks 🙏
Awesome YouTube channel
We learn a lot 👌👍

[brian]

Dear Dave, thank you for your excellent way of educating the public. I do get a great deal of help from your video and enjoy this kind of learning. I am a new member (study buddy) here. I wonder if I am qualified for early access to the hidden videos in Immunology. I am going to take an exam in a few days...

[secretsocietyserver]

Thanks! Today I learned that T cells undergo negative selection to eliminate self targeting T cells, and positive selection to allow non self targeting T cells!

[nicholasgardiner]

Thanks Professor Dave, great elocution.🎉❤

[DylanMcGowan]

Is it possible you could do a video on hiv medicines out there and explain how they work and their effecacy? Symtuza is a brand im interested in learning about.

[keegan]

hey professor farina, are you ever going to cover nuclear + radiation physics? i feel like a general explanation of radiation science in your style would help to dispel a lot of the anti-nuclear rhetoric in north america and europe

[shelbyg]

This is what I study for my job! My company creates CAR T Cell therapies for cancer treatment.

[Huebert-zpuq]

Do you think you could do a video on positive and negative selection in detail? We covered it in courses but it was one of the more confusing topics. Going through things like the antigen presented during positive and negative selection, AIRE etc. I think it’s a high yield topic that also lets you explain autoimmune a little and how the system can go wrong

[NuNugirl]

Dave can you please explain the effects on B cells after splenectomy, because I have ITP. Thanks.

[donchristie]

Things going well, Wael
(Been trying to find the time to learn more about Lebanon)

[anonimusgamingnation]

how i get acces to full series i am gonna have an exam on imunobiolgy and you help me a loot with your videos and i am stuck at adapative imunity and i know you have recorded all the videos just curios how to acces them if i become a membre i have acces to them ?

[josemadrid]

So can the more knowledge about T-cells are able to help in the fight against cancer?

[defiant]

T Cell therapy is being tested to help with Autoimmune diseases like Lupus.

[Tom_Tom_Club]

Please do a video on Dr. Fatima's videos and/or the Dark Matter doesn't exist conspiracies