For those of you who haven't heard from me in a really long time (which is probably most you) please blame it on second year. My friends and I love to joke about how second year is like first year on steroids (or on crack) which basically means more information in less time. Seriously, we have exams like every two weeks. It's unholy!
But, besides all that, we are finally learning immunology. I was really excited about it (and still am) because it's SO cool. The body's defensive are incredibly extensive and intensive. And just thinking about the number of pathogens we interact with everyday (germs in our food, on our doorknobs, in our sneezes...) it is kind of amazing that we are not ill every second of every day.
Unfortunately, with such strength of character, comes ridiculous complexity. And I seriously mean ridiculous. Our innate immune system is, in part, composed of the "complement pathway." In general, it's basically a whole much of molecules that are in our bodies that can bind to the membrane of bacteria and poke holes in it. Literally. Okay, that makes sense. But the molecules that are involved in the complement cascade make me wonder if scientists and doctors lack the common sense gene. Here is a quote from my lecture notes.
"C1s, which is cleaved to become a new serine protease, cleaves C4 into C4b which binds C2 which is cleaved into C2b, forming the macromolecular C4bC2b complex. This cleaves C3 into C3b. Binding of C3b into the complex forms the enzyme C4bC2bC3b. This C5 convertase activates the lytic pathway by cleaving C5 to C5b, which complexes with C6 into C5bC6 and C7 into C5bC6C7. This complex displays a high affinity binding site for C8. The formation of the C5b678 complex retrieves C9 to form C5b6789."
And that's only the classical pathway! Hmph!
