The Complement System: Classical, Lectin, and Alternative Pathways

We are learning about the features of innate immunity, and one that is often overlooked is the complement system. This is a very complicated ensemble of proteins circulating in the bloodstream that activate each other in a specific sequence that results in immune system engagement to kill pathogens. It's quite involved with multiple possible pathways, so this will take a while, but let's dig into this important system now!

Script by Stephanie Melchor

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

[Liberperlo]

This is the best video on complement I have seen. I'm not an immunologist or even a student. Just a librarian who is fascinated by the immune system. Thanks!

[alemantewassie]

This was the best video I have ever watched about Complement system. Only someone who have left a few minutes left to cover this topic knows how fantastic this work is. Thank you Prof Dave.

[emdoubleyew]

This makes re-reading my immunology textbook nearly painless. Lovely stuff you have.

[sumeet]

Professor Dave, I am an MS1(first year medical student) and my first block includes immunology. I wanted to say your videos including this complement protein video are more concise than the lectures from my immunology professor. Thank you!

[Hannah-yzgj]

you don't know how much you helped me understand this topic. i was on the verge of crying going through our readings but this video really clarified a lot of things (for some reason it seemed like our lecturers were also speaking a whole different language while teaching this). thank you so much!

[MissD]

This is really excellent. Also the speed at which you speak is perfect for people who are trying to understand something, other videos I have to pause and re listen because they’re talking too fast, but this is perfect!

[bethuelmutiti]

I really don't know how my Med School would be without you sir 😭🙏❤️🔥. A Big thanks to you for making my life easy

[dmskarunaratne]

no words. simplistic way to teach complex theory with best illustrations. thank you. Best video on this topic.

[Sydney-gkgh]

This is by far the most clear yet comprehensive breakdown of these pathways that I have seen. Thank you so much, you just tied together so many loose ends from days of studying!

[shaqthedoc]

dude you just cleared the evolutionary aspect of the complement system, great job👍🏻

[wassyjalal]

I used to watch your videos way back in high school for AP bio and your videos are still carrying me as a first year medical student lmaooo. Could not have made it where I am today without you

[whbclaire]

Thank you so much for this. In my role as a medical writer, I have been doing some programs on paroxysmal nocturnal hematoglobinuria, which is a disease of the complement cascade. This clearly explained a lot of the things I was confused about.

[madelinegreene]

I have an immunology test next week for my first year of grad school--this has been SO much more helpful than anything my professor has said!

[ferhanslamang]

I had no idea where all these complement proteins came from, but you simplified it really well for me.

[ValeriaSteiger]

Thank you soooo much, seriously! After studying medicine for 4 yrs i did not just learn it by heart, but understood it

[sagacious_Codyt]

This has been really helpful. I've been struggling to understand the complement cascade but with how you've laid everything out, I'm subliming..
.. Thank you so much

[immune]

Very comprehensive with just enough detail for competence but not too overwhelming!

[zhaomengna]

Very detailed and direct illustration and description. Learn more from these lectures. Thanks a lot.

[pamtarlow]

Great video. I am a pharmacist trying to help my patients with Long Covid and appreciate the excellent education here.

[birukgossaye]

Hey Professor, I understand almost everything you explain so please start makin videos about music theory and all. You're the best teacher ever.