B and T cell responses Flashcards
T helper 1 cells secrete which two cytokines?
a. Interferon gamma and tumor necrosis factor
b. Interleukin 4 and interleukin 5
c. Interleukin 9 and interleukin 10
d. Interferon gamma and interleukin 13
a. Interferon gamma and tumor necrosis factor
Which of the following cells are not involved in cross-presentation of antigens?
a. Macropahges
b. Denditic cells
c. Basophils
d. B cells
e. All the above are involved
c. Basophils
T helper 2 cells secrete all of the following except:
a. IL-12
b. IL-10
c. IL-13
d. IL-4
e. IL-5
a. IL-12
**secreted by Th1 cells
What are the four things secreted by T helper 1 cells?
TNF
INF gamma
IL-12
IL-2
The interleukin responsible for the differentiation of T helper 1 cells is ___ and the one responsible for the differentiation of T helper 2 cells is ____.
Th1 = IL-12 Th2 = IL-4
T helper 1 cells respond against viruses and tumor infected cells of the ____ immunity and T helper 2 cells are part of the ____ immunity.
Th1 - cell mediated immunity
Th2 - Humoral immunity
Which of the following is false?
a. Th1 cells are effective against intracellular bacteria and protozoa while Th2 cells are effective against extracellular parasites
b. Th1 cells active cell mediated immunity while Th2 cells activate humoral immunity
c. Interferon gamma is going to stimulate cytotoxic T cells to become CTL’s and they’re secreted by macrophages and activate NK cells
d. IL-4 is responsible for glass switch to IgE and IL-5 is responsible for class switch to IgA
c. Interferon gamma is going to stimulate cytotoxic T cells to become CTL’s and they’re secreted by macrophages and activate NK cells
**its secreted by actiavted NK cells and they’re potent activators of macrophages
T helper 2 cells target all the following cells except:
a. Mast cells
b. Macrophages
c. Eosinophils
d. Basophils
b. Macrophages
**also target B cells
**macrophages, NK cells and CTL’s are all main effectors of Th1 cells
Which interleukin is responsible for the proliferation of T helper cells?
IL-2
What are the steps to activate a naive T cell?
- TCR binds specific antigen displayed by MHC II binding the CD4 co-receptor
- CD28 binds B7 on APC
- LFA-1 (CD11) binds ICAM on APC
- CD40L / CD154 binds CD40 on APC which activates the APC to express more B7 and secrete IL-12
Which interleukin is necessary for the memory T cell to stay alive?
IL-7
True/False: CTL’s are responsible for producing cytokines to help kill infected host cells expressing antigens.
False
**T helper cells produce cytokines
True/Flase: Both CD95 and Perforins are ersponsible for activating caspases.
False
**Granzyms and CD95/ Fas-ligand
True/ False: Both granzyms and perforins enter the target cell by receptor mediated endocytosis.
True
T independent B cells are activated by which non-protein antigens?
Lipids
Polysaccharides
Nucleic acids
Which of the following is false?
a. T dependent activation produce only IgG and can induce germinal center responses
b. With T independent activation there is no class switching and differentiation is induced by the BCR signaling alone
c. Dendritic cells process antigens into peptides which are then presented with MHC to T cells in T dependent activation
d. T dependent activate via BCR’s but depend on signals from T helper cells to cause division/ differentiation
a. T dependent activation produce only IgG and can induce germinal center responses
**T independent only produce IgG since there is no class switching with this kind of activation
What are the co- stimulatory signals of naive B cell activation?
CR2 (CD21) binding to C3d
What are the accessory molecules of naive B cells?
CD81 and CD19
Which of the following is false regarding plasma cells?
a. Early plasma cells are short lived vs. secondary plasma cells are long lived
b. Early plasma cells home to the bone marrow, gut, and lactating mammary glands
c. Early plasma cells produce IgM mainly but also produce small amounts of IgG
d. Primary plasma cells arise from germinal centers while secondary plasma cells arise from the memory B cells
b. Early plasma cells home to the bone marrow, gut, and lactating mammary glands
**true for late plasma cells, early plasma cells home in red pulp of spleen and medullary cords of lymph nodes
True/False: B cells that present antigen are 100,000 times more specific to them than non- specific antigens.
True
Which of the following interleukin is responsible for differentiation of B cells into plasma cells?
a. IL-2
b. IL-4
c. IL-6
d. IL-5
c. IL-6
**all the others are responsible for proliferation of B cells
A decrase in CD40 L on T cells can lead to what syndrome?
Hyper IgM sundrome
True/Flase: Isotype class switching results in the light chain gene switching.
False
** heavy chain gene switch
Isotype class switching requires the binding of ___ and ___ regulated by ___ that are realsed from T helper cells.
CD40 on B cells and CD40L on T cells regulated by cytokines
Which of the following immunoglobulins is the first to be secreted by B cells using IL-2, IL-4, IL-5?
a. IgG
b. IgM
c. IgA
d. IgE
b. IgM
Which of the following uses IL-4 to activate and produces immunity against parasites and mast cell degranulation?
a. IgG
b. IgM
c. IgA
d. IgE
d. IgE
Which of the following uses mucosal tissues, cytokines, and TGF- beta for mucosal immunity?
a. IgG
b. IgM
c. IgA
d. IgE
c. IgA
Which of the following has phagocytic responses when activated and uses IL-4 to activate one of the subclasses?
a. IgG
b. IgM
c. IgA
d. IgE
a. IgG
Which of the following arouses IL-5 that activates eosinophils and also arouses BAFF?
a. IgG
b. IgM
c. IgA
d. IgE
c. IgA
Which of the following activates the complement system and can also be transferred through the placenta to a neonate?
a. IgG
b. IgM
c. IgA
d. IgE
a. IgG
True/False: Affinity mutation only occurs in humoral immunity and T helper cells regulate somatic mutations.
True
What two things are responsible for promoting prolonged interactions between B and T cells and is essential for a response within the germinal center?
LY108 and SLAM assocaited proteins
True/False: With a primary exposure we see more IgG produced whereas in a secondary exposure we see more IgM produced.
False
**primary = IgM secondary = IgG
With a primary immune response we have a longer ___ phase mainly composed of naive B cells and with secondary immune responses we have a shorter __ phase that consists of higher immunoglobulin affinity and levels along with memory B cells.
Primary = long lag phase Secondary = shorter lag phase
Which of the following is false regarding neonatal immunity?
a. Maternal IgG is transported by the neonates FcRn across the placenta to the fetus or from collostrum across the gut epithelium
b. A newborn has a natural passive immunity that protects them for up to 3-4 months causing them to have a high incidence of hemophilus influenza bacteria
c. The initial or primary immune response has a prolonged lag phase which doesn’t produce many immunoglobulins
d. All the above are true
d. All the above are true
Which cells are going to have ADCC’s?
NK cells
Macrophages
Eosinophils
Neutrophils
