Neisseria here to answer any and all questions about the immune system. Wonder what's happening when you're sick? Or why do allergies tend to overlap or get worse over time? Or how vaccines work? (Spoiler: THEY ARE FREAKING IMPORTANT. GET THEM) Then ask away! I'll be taking questions all day, and will also take any stragglers tonight/tomorrow.
A bit about my background: I'm currently at the end of my PhD in Immunology, so I've got a lot of knowledge about what is going on in the research world. Almost all my experience has been with mice, so I can also take any questions about what mice research is like. As for hands on or practical advice? I am not a doctor, and I have yet to delve in the world of drug development. So I'll probably only give you vague conjectures for anything related to those, and really, you should see a medical doctor if you have an issue =P.
Finally, a reminder for just how kick ass the immune system is. Here's a video of cytotoxic T cells killing a cervical cancer cell:
The cancer cells are the larger blobs in the middle, while the T cells are the smaller circles that are all up on the cancer cell. Surface proteins on the T cell have recognized the tumor, and are now releasing all sorts of things to kill it. Glorious, glorious cell death at 0:15.
Image from deviantart user Velica
Video from youtube user CD84U, attributed to "Tom Hickin (with help from Claudia Nunes and Richard Stanton) as part of his CUROP project at Cardiff University."