0604 - Effector and memory T cell - EG Flashcards
Give an example of a disease to which adaptive immune response can be life long.
adaptive memory to measles via either vaccination or infection results in lifelong immunity.
What are the four characteristics of memory (immune)?
quantitative (more memory than niave cells to a specific antigen), qualitative (more readily converted to effectors), altered recirculation (from lymphoidal tissue to non-lymphoidal), long-lived.
What is dendritic cell licencing?
Often dendritic cells need to be conditioned by the CD4 response in order to be able to equip the DC to activate a CD8 cell properly
What are the 3 phases of lymphocyte development from their activation due to stimulus to immune memory formation?
Expansion phase with mass clonal expansion to eradicate the pathogen; contraction phase to reduce lymphocyte count post resolution; residual memory cells to be able to elicit effective response on secondary exposure.
What chemokine receptor maintains lymphocytes in their lymphoid organs?
CCR7
What is STAT? What do they do?
acronym for signal transduction and activation of transcription. STAT signal downstream of receptor, phoshporylate, form dimers, and then enter nucleus to regulate transcription.
What is the signature cytokine of Th1 cells?
interferon-gamma
What is the signature cytokine of Th2 cells?
IL-4
What are Th1 cells particularly good at activating?
inflammatory response, macrophages, and dendritic cells to kill intracellular pathogens.
What cytokine stimulates the differentiation of a T cell to a Th1 cell?
IL-12; receptor signals to STAT4
What is the master regulator gene that causes T cell differentiation to Th1?
T-bet
List some actions of Th2 cells
activation of B cell proliferations, stimulate eosinophil recruitment and activation, stimulate mucosal secretion (e.g. of goblet cells)
What molecules help the differentiation of a T cell to a Th2 cell?
IL-2 (STAT5) and IL-4 (STAT6)
What is the master regulator gene that causes T cell differentiation to Th2?
GATA3
What IL activates mast cells by which Th cell?
IL-9 of Th2 activates mast cells
What IL activates eosinophils by which Th cell?
IL-5 of Th2 activates eosinophils
What is the function of Th17 cells?
recruit and activate neutrophils, stimulate epithelial cells such as keratinocytes to secrete beta-defensins, act against extracellular bacteria and fungi.
What is the master regulator gene that causes T cell differentiation to Th17? What activates this?
ROR-gamma-t, activated by STAT3 (STAT3 activated by secretion of IL6 and IL-!beta cytokines by DC)
What is the master regulator gene that causes T cell differentiation to Tfh?
Bcl-6
What is the master regulator gene that causes T cell differentiation to Tregs?
FoxP3
