So, yeah, what the hell are T helper and cytotoxic cells, antibody secreting cells,
complement, and this whole antibody dependent versus independent immune
The norms’ notes kinda suck on this and are more confusing
Sometimes, you really do need to paint the picture to learn the info,
this might help add some puzzle pieces that will put the rest of the material
in a context.
MHC (aka major histocompatibility complex) is a receptor protein on
cells that recognizes and binds to antigens (small peptides, garbage in interstitial
There are two varieties:
the first type, MHC-I, is present on all body
It is one way of tagging our cells as “self.”
The second type, MHC-II, is
only present on antigen-presenting cells (APCs) such as dendrites,
macrophages, and B cells.
Antigen-presenting cells ingest microbes, toxins, and
other debris, glue the digested parts to MHC-II, and stick it on the outside of their
cell membranes sorta like the kid on the playground with a new toy – look at this!!
(bad joke but you all get the meaning)
So, MHC-II-bearing cells will “present” antigens from stuff they ingested, while
MHC-I-bearing cells will “present” antigens from
: for example, if they are
infected with a virus, they will chew up a little of it and post it on their surface, to
let other cells know that they, well, need to be killed.
T-cell mediated immune reaction: