General Immunology Flashcards
What is the mechanism of respiratory burst?
O2 consumption increases
NADPH oxidase activated
2e + O2 -> O2-
O2- + H2O -> H2O2 (hydrogenperoxide) = toxic
What is the difference between phagosome and phagolysosome?
phagosome: antigen trapped in vacuole in neutrophil
phagolysosome: when phagosome fuses with primary granules
What are opsonins?
proteins that enhance contact and phagocytosis by neutrophils or other phagocytes
What is diapedesis?
That neutrophils are triggered to leave the circulation by crossing capillary walls.
What are CAMs?
Cellular adhesion molecules on endothelial cells where neutrohils attach to
What are the phases of phagocytosis in neutrophils? (4)
- chemotaxis
- adherence/attachment
- phagocytosis
- destruction
Do Gram positive and Gram negative bacteria have a thick or thin peptidoglycan layer?
a. both thick
b. both thin
c. + thick, - thin
d. - thick, + thin
c. + thick, - thin
How do macrophages develop?
a. hematopoietic cells > monoblast > monocytes > macrophages (in circulation)
b. hematopoietic cells > monocytes > monoblast (in circulation) > macrophages
c. hematopoietic cells > monoblast > monocytes (in circulation) > macrophages
d. hematopoietic cells > monocytes > monoblast > macrophages (n circulation)
c. hematopoietic cells > monoblast > monocytes (in circulation) > macrophages
What cells express TLRs?
a. predominantly macrophages
b. predominantly neutrophils
c. predominantly NK cells
d. predominantly T-cells
a. predominantly macrophages
What TLRs are present on the cell surface membrane?
a. TLR1, 2, 4, 5, 6
b. TLR 3, 7, 8, 9
a. TLR1, 2, 4, 5, 6
What TLRs are found intracellular?
a. TLR1, 2, 4, 5, 6
b. TLR 3, 7, 8, 9
b. TLR 3, 7, 8, 9
Nitric oxide killing is used in?
a. neutrophils
b. macrophages
b. macrophages
Microglial cells are macrophages in?
a. brain
b. kidneys
c. connective tissue
d. lymphoid tissue
a. brain
Mesangial cells are macrophages in?
a. brain
b. kidneys
c. connective tissue
d. lymphoid tissue
b. kidneys
Histiocytes are macrophages in?
a. brain
b. kidneys
c. connective tissue
d. lymphoid tissue
c. connective tissue
What is correct about macrophages?
a. first type of cells to appear in circulation and can repeatedly phagocytose in response to invasion of microbial antigens
b. they secrete anti-inflammatory cytokines that prevevnt fever
c. they have MHCI and selected macrophages also have MHCII
d. they have no ability to secrete proteins
e. they are lymphocytes
c. they have MHCI and selected macrophages also have MHCII
What is correct about neutrophils?
a. They can rapidly destroy antigen by phagocytosis and respiratory burst
b. They are lymphocytes that are in the first cells to destroy antigens.
c. They are major producers of IL-1.
d. They are efficient antigen-processing cells.
e. All of the above.
a. They can rapidly destroy antigen by phagocytosis and respiratory burst
APC include which of the following?
a. dendritic cells
b. selected macrophages
c. B cells
d. T cells
e. answers a, b and c
f. answers a, b and d
e. answers a, b and c
What is correct about antigen?
a. highly degradable proteins and large inert substances are not good antigens
b. large molecules are good antigens, therefore polysaccharides with simple repeating sugars are good antigens
c. large complex proteins are good antigens
d. antigens do not drive an immune response
e. lipids, but not lipoproteins, are good antigens
c. large complex proteins are good antigens
Lymphoid stem cells give rise to:
a. T-cells and B-cells
b. T-cells, B-cells and NK cells
c. T-cells, B-cells, NK cells and lymphoid dendritic cells.
d. T-cells, B-cells, lymphoid and myeloid dendritic cells.
c. T-cells, B-cells, NK cells and lymphoid dendritic cells.
Lymphoid stem cells give rise to:
a. PMN
b. Eosinophils
c. Monocytes
d. NK cells
d. NK cells
What is true about T-cells?
a. CD4 are helper cells, CD8 are cytotoxic cells
b. CD8 are helper cells, CD4 are cytotoxic cells
a. CD4 are helper cells, CD8 are cytotoxic cells
What is true about Th-1?
a. intracellular pathogens + tumors
b. extracellular pathogens, neutralization of toxins and viruses in body fluids, activation of other cells, abnormal regulation > allergies
c. recruitment and activation on target cells to stimulate pro-inflammatory molecules, synergizing with TLR ligands
a. predominantly secrete IL-2, IFN-gamma and TNF-bèta (intracellular pathogens + tumors)
What is true about Th-2?
a. intracellular pathogens + tumors
b. extracellular pathogens, neutralization of toxins and viruses in body fluids, activation of other cells, abnormal regulation > allergies
c. recruitment and activation on target cells to stimulate pro-inflammatory molecules, synergizing with TLR ligands
b. extracellular pathogens, neutralization of toxins and viruses in body fluids, activation of other cells, abnormal regulation > allergies