T-cells Flashcards
What is the co-stimulatory signal found on T-cells
CD28 receptor on Cd4+ t cells, and the b7 ligand found on antigen presenting cells
What is anergy, and what occurs when it happens?
Anergy is the process where T cells are no longer responsive to antigen stimulation because there is no secondary signal
IT IS A SELF TOLERANCE INDUCTION???
What is the function of IL-2 in t-cells
Involved in T-cell proliferation
What role do CD3 proteins play in T-cell activation?
CD3 resides on the t-cell membrane, and elicits signal transduction using ITAMS
Is CD 28 a receptor or a ligand?
A receptor on T cells!
What is the role on CD40 IN T-cell binding?
The DC40 ligand arises from the is found on helper t cells, and binds to CD40 on macrophages and b-cells
-This strengthens the bond between CD-28 receptors on t-cell and b7 ligand
What is the role of INF gamma and what does it produce?
IFN is produce by Th1 cells, and activate macrophages to engulf bacteria
What does IFN gamma inhibit
Th2!
What do Th2 produce? What do they stimulate and block?
IL 4- E to A class switching, eosinophil production, promote b-cell growth
IL 5- stimulate Ig-A production, eosinophiles
IIL-6 - pro inflammatory, b cells maturation
IL-10- inhbibitory against APCs
-IL-4 blocks Th1
What doe T-17 secrete?
IL-17, IL22 (anti-inflammatory/antifungal)
How does a dendritic cell stimulate t-cell diffrentiation?
It phagocytes the the microbe, and depending on that microbe (tlrs) it will direct the t cell to differentiate.
What cytokines block TH17?
INF-gamma, Il-4
What are the two ways tha CD4 cells stimulate CD8 cells?
CD4s produce cytokines that help in B cell proliferation (IL4, IL-6)
AND
They enhance ability to APCs to help B-cells proliferate
Do CD8 cells also gave CD 28 receptors?
YES!
What are the enzymes that CTLS inject to cause apoptosis
Granzymes and Perforin
What is a one strategy for immunosuppression in transplants?
Blocking T-cell activation
Describe the mechanism of DiGeorge Syndrome:
Lack of a thymus
- heart defects, low calcium, low t-cells .
Are B cell defects of T cell Defects harder to treat?
T cell defects because t cell help b-cell proliferate.
What are the combined immune defiency disorders?
SCID and and Winscott Algdridge disease ( abnormal platelets)
What are are the 3 hallmarks of DiGeorge Syndrome?
cardiac issues, underdeveloped thymus, low calcium level
What is the genetic deletion that cause Digeorge Syndrome?
22q11.2
What are mitogens?
Proteins that stimulate mitosis
What is the outcome of partial DiGeorge?
they will likely ok, since some t-cells are still being made
What are stages of erythrocyte development?
Protoerthyrocyte Basophilic Erythroblast Polychromatic Erythroblast Orthochromatic Erythroblast Reticulocyte, Eryhtrocyte
What are the stages of granulocyte development?
Myeloblast Promyelocyte Neutrophilic Myelocyte Neutrophilic Metamyelocyte Neutrophilic Stab cell Neutrophil