For Immunology Chapter 11 Day 1 “Signal 1” occurs when a TCR recognizes antigen within an MHC molecule on an antigen presenting cell. Then, transcription of IL-2 and CD25 occur.  What is the significance of the upregulation in these two genes? What molecular interactions would you expect to find in cSMACs and pSMACs? What purpose … Continue reading T Cell and APC Signals 1, 2, and 3!

For Immunology Chapter 9 Day 3 During the selection process in the thymus, thymocytes mature from CD4+ CD8+ (DP) cells to being single positive (SP) for either CD4 or CD8. Briefly describe the following: Instructive model Stochastic (random) model The kinetic signaling model is the currently accepted idea for explaining why cells commit to a … Continue reading Wrapping Up T Cell Development with a Discussion of Death (or Not)

For Immunology Chapter 9 Day 2 After jumping through the hoops necessary to make functional α and β chains of their TCRs, ~95% of CD4+CD8+ (DP) thymocytes die from what? Because of this fact, why are quotes necessary when someone says thymocytes “learn” or are “educated” in the thymus? What stages of T-cell development (DN1, … Continue reading T Cell Development – Selection and More Selection