I have just entered into immunology research and I need to know the following: Please try to help me by answering the following questions if you have expertise.
1. What's the reason behind using isotype controls in an experiment? I need the mechanism behind the usage of isotype controls in experiments (often when we go for flow cytometry)?
2. What is the principle of using IL-4 and GM-CSF to generate DCs from monocytes (i.e. for generating MDDCs)? I understand IL-4 is an anti-inflammatory Th2 cytokine!
3. What does PolyI:C do to make DC mature?
2. Good question. It works but I'm not sure anyone really knows why or how. Some say the IL4 suppresses CD14 expression but others say that GM-CSF is enough. I think of monocytes as a non-activated myeloid cell that can differentiate to macrophage or DC depending on the stimulus.
3. PolyI:C activates DC through a TLR. Can't remember which one - TLR9 I think. This mechanism probably arose as a way of responding to viruses via the presence of nucleic acid.
Hope all that is helpful.