Last week was a pretty slow week with most of the group on vacation. I continued to watch the jurkat cells and count them on a pretty regular basis. This week there should be enough cells to harvest them and extract RNA. I also observed the extracting of PBMC's (peripheral blood mononuclear cells) which contain the lymphocytes and monocytes (cells of the immune system). When spun at high speeds the blood separates into different levels according to density. The lymphocytes and monocytes form a buffy coat under the layer of plasma that you pipette out. It's important to get good separation of the blood for clear results in many of the tests in the lab. Once the pbmc's were separated Jie showed me how they select the T cells (a type of lymphocyte) from the sample magnetically. T cells express CD3 on the cell surface. The white blood cells are mixed with CD3 antibodies that are attached to an iron molecule. These micro beads only attach to the cells expressing CD3 and the whole sample is run through a filter with a magnet. It was cool to see the process from beginning to end starting with whole blood and ending with a specific type of lymphocyte.

It also looks like I've got the rest of the data I need for my project. It's exciting to see the last bits come together. So far our data suggests that the CD56hi cells we were looking for are present pre-transplant in babies with no thymus function. This does not support the hypothesis in another paper, based on mice, which proposes that this type of cell is derived from the thymus.