June 25, 2017
So far, I have done many projects in my internship in the Moore Lab. Most of my projects have used mice models to study secondary bacterial infections after an initial infection with Influenza. This project is a little different and is focused more on immunology, which I love.
Before I discuss the project, a little background information is necessary. Toll like receptors are receptors found on immune cells that recognize pathogen-associated molecular patterns (PAMPS), leading to the activation of the immune system. Each Toll Like Receptor (TLR) recognizes a foreign particle found in pathogens. There are eleven TLRs in humans and thirteen TLRs in mice.
In my favorite project, we gave mice an initial infection with either PBS (a placebo) or Influenza. We waited five days, euthanized the mice, collected immune cells, lysed the cells, and did a quantitative reverse transcriptase PCR to determine the relative RNA levels of each Toll Like Receptor. In the experiment, we found that TLR9 RNA levels were unregulated when there was an infection with Influenza while there is no significant increase or decrease in the other Toll Like Receptors.
This is a very strange result because TLR9 recognizes unmethylated Cytosine and Guanine dinucleotides, which are found in bacteria NOT Influenza. TLR9 was not supposed to increase. Toll Like Receptor 7, on the other hand, recognizes single-stranded RNA, which is in Influenza. According to some of the research articles I read, sometimes stimulation of one TLR can lead to an up regulation of another TLR. My hypothesis is that stimulating TLR7 leads to an up regulation of TLR9, but more work on this idea needs to be done. So far, this has been my favorite project. I will keep you all updated on future results.