Second Week

My weekly schedule is about the same- I go to the lab three days a week and do immunohistochemistry (IHC) on samples of brain tissue. This week I attended a conference on amyloid which is a protein in the membrane. In Alzheimer's patients, the amyloid breaks off and forms plaques outside the cell that disrupts synaptic signaling.

What I Learned: There are two types of samples you can do IHC on: floating tissue and mounted tissue. Last week, I watched/helped someone do IHC on floating tissue, and this week I did it on mounted tissue. There are a few differences in the protocol- (for mounted tissue) the tissue is mounted onto slides at the very beginning of the process and is rehydrated and put in the oven before the regular procedure starts. Also, we use a special marker, that keeps liquid from crossing over, to draw a circle around our samples so that the primary antibodies actually affect the sample (rather than floating onto the surrounding slide).

I'm not 100% sure what to analyze from my IHC yet. After we get a successful IHC, we analyze it. For example, we can look for which areas the protein concentration is highest, or whether or not the protein is even there, etc.
I have a few ideas:

• Do IHC on a regular (without Alzheimer's) brain tissue sample for tau and a separate IHC for amyloid. Then do IHC on Alzheimer's brain tissue sample for tau and a separate IHC for amyloid. Compare. Then do IHC on brain trauma tissue for tau and a separate IHC for amyloid and compare with Alzheimer's and regular tissue.
• There are five stages of brain trauma tissue that we have starting from Stage 1 (which is the least severe) till Stage 5 (which is the most severe). Do IHC on tissue from each stage for tau and amyloid and note differences. Do IHC on Alzheimer's and compare all the results. (I'm leaning toward this one more).

I might not do either of them because as I learn more, I change my plan (this would be the third time I've changed my plan in the last 2 weeks).