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Now comes the action part of the story. Our immune system consists of many different kinds of cells. The important thing to remember is that each cell mainly does two things: signals other cells, and acts upon receiving a signal. The resulting action is quite fast and profound.
When we last left off in the movie, a presenting cell scavenged our body for things that are not usually present, and grabbed that substance to show a helper T cell a receptor (the signal) on its surface (Lower right corner of frame 1, small plum-colored cell). The helper T cell understands that signal to mean that something bad is in the body, and then communicates with a B cell (frame 2, orange cell), coaxing it to start dividing by releasing cytokines (frames 3 and 4).
There's a lot of terminology and lots of players involved in an allergic reaction. So if you're wondering why (like I was in those very uncomfortable 24 hours following my hives/rash reaction) your medication takes a while to calm down your swelling, itching, and general misery, remember that all these players need to be calmed down as well!
When we last left off in the movie, a presenting cell scavenged our body for things that are not usually present, and grabbed that substance to show a helper T cell a receptor (the signal) on its surface (Lower right corner of frame 1, small plum-colored cell). The helper T cell understands that signal to mean that something bad is in the body, and then communicates with a B cell (frame 2, orange cell), coaxing it to start dividing by releasing cytokines (frames 3 and 4).
There's a lot of terminology and lots of players involved in an allergic reaction. So if you're wondering why (like I was in those very uncomfortable 24 hours following my hives/rash reaction) your medication takes a while to calm down your swelling, itching, and general misery, remember that all these players need to be calmed down as well!