Random Remediation Flashcards
(25 cards)
Which TH cell is does cell-mediated immunity & which does Humoral immunity?
TH1 = Cell mediated (1 cell eliminates the bad guy) TH2 = Humoral immunity (B cell produces lots of Abs)
What causes commitment towards Th1 cells?
Activated macrophages/IL-12
What 2 things cause TH2 commitment?
IL-4/Absence of IL-12
What co-stimulatory cell surface protein do activated T cells (TH cells) express?
CD40L
What cells express CD40?
APCs
- What is the major cytokine of TH1 cell mediated immunity?
2. What 2 things does it stimulate?
- IFN-y
2. M# activation & B-cell ab opsonization
Where are CD8 Tcells activated/what activates them?
Lymph nodes by DCs
What does a DC need to express to be a “real” DC? Where does this happen?
B7 in lymph node
What is the T-cell zone called where DCs meet up with Naive T-cells?
Parafollicular cortex
What 4 cell surface molecules are needed to activate(signaling cascade) a T cell?
TCR, CD3, CD4, CD8
What are the 4 CD3 proteins?
Gamma, Delta, Epsilon, Zeta
What are the co-stimulatory molecules that a T cell must receive to become activated (not when it has already been activated)?
B7 proteins (CD80 & CD86)
What drives T cell proliferation?
IL-2
How does the IL-2 receptor become “high affinity”
Expression of IL-2Ralpha chain/ formation of IL-2Ralpha,beta,gamma complex
What is the job of a TH1 cell vs. a TH2 cell?
TH1 = Activates M# & induces B cells to make OPSONIZING abs. TH2 = Activates B cells to make NEUTRALIZING abs. & does "various" things to M#
How can a CD8 T cell become activated by a DC?
Cross presentation
2 Ways CD4 cells can Activate CD8 Cells
- Cytokines
2. Enhance APC ability to stimulate CTL differentiation
How does a CD8 cell kill a target cell?
Releases its granule contents- perforin & granzymes- in an immunologic synapse –> apoptosis
What do CTLs secrete after killing something? (I’m not sure if it is after, but it will help remember)
IFN-y to activate M#
What are the CTL’s two mechanisms of killing?
- Granzyme & perforin –> apoptosis
2. FasL-Fas binding –> apoptosis
3 Functions of GammaDelta T cells
- First line of defense
- Regulatory cell
- Bridge between innate and adaptive responses
Are GammaDelta T cells MHC restricted?
No, they do NOT need APCs, they can recognize unpresented antigens
NKT cells are different than NK cells, their function =
Release IFN-y & IL-4 to promote/suppress different immune responses
What do NKT cells recognize?
self & foreign lipids and glycolipids
