Picture this: A 43-year-old nurse practitioner (that’s me) on the floor of her 8-year- old daughter’s
Disaster Area bedroom, drawing different colored blobs with pointy things sticking out of them and rectangular-shaped objects floating towards them.
A few triangles are trying to get involved but there isn’t much space left on the poster board. The letters “C” and “B” and “A” and the numbers “4” and “3” figure prominently in the project. Arrows point one way, then another, up, down, diagonally. Things are connected by lines, but after several minutes, it’s impossible to tell which lines are connected to which objects.
When I am done, I have clearly failed to figure out the complement system, although I have created a pretty good facsimile of a blindfolded 3-year-old’s efforts to copy a Jackson Pollack painting.
My advice to anyone having trouble with basic immunology is to first look at the big picture…
Diagramming worked great for understanding the Kreb’s Cycle when I was in nursing school. I read, reread, and then re-reread the chapters on the complement system in 3 different basic immunology textbooks. I Googled it. I Wikied it. I watched a podcast given by a lovely immunologist in California whose name I can’t remember. But I just can’t seem to get the big picture.
OK, I get that there are three ways to activate the complement system. I get that antigens and antibodies are involved. I’m trying to memorize all these pathways and numbers and enzymes, and then it hits me: Mrs. MacDonald’s 9th grade American Experience class!
When we were learning about the design and architecture of Washington DC, Mrs. MacDonald taught us what is possibly the most useful 3-word phrase in the English language: “Form Follows Function.” When I started thinking about the complement system backwards, it suddenly all made sense.
The point of the complement system—its function—is to blow stuff up that doesn’t belong there. What do you need to blow stuff up? Bombs. What are the equivalent of bombs in the immune system? Membrane Attack Complexes. What do you need A LOT OF to build a MAC? C3b. What is the point of the 3 pathways of activation? To build C3b.
Realizing that rote memorization is not the secret to understanding the immune system has helped me tremendously. So my advice to anyone having trouble with basic immunology is to first look at the big picture, figure out what the desired end result is (the function), and then work backwards from there (to understand the form). If you’re like me, you will save yourself a lot of frustration. Not to mention a lot of art supplies.
AUTHOR PROFILE: Elizabeth Kirchner, CNP, is a nurse practictioner at the Cleveland Clinic in Cleveland, Ohio, and the Education and Curriculum Chair of the Rheumatology Nurses Society.