Cells/ Organs/ Microenvironments Flashcards
(137 cards)
1
Q
What kind of cells have the ability to differentiate into many types of blood cells?
A
HSCs = Hematopoietic Stem Cells
2
Q
What is the highly regulated process where HSCs differentiate into mature blood cells?
A
Hematopoiesis
3
Q
Where do all red/ white blood cells develop from?
A
pluripotent HSCs
4
Q
What are the 2 primary lymphoid organs?
A
Thymus/ Bone Marrow
5
Q
Where do immune cells develop from immature precursors?
A
Primary Lymphoid Organs
6
Q
Where do mature antigen-specific lymphocytes first encounter antigens/ begin differentiation into effector/ memory cells?
A
Secondary Lymphoid Organs
7
Q
What are 4 secondary lymphoid organs?
A
Spleen/ Lymph Nodes/ Gut/ Mucosal Tissue
8
Q
Where does hematopoiesis occur?
A
Bone Marrow
9
Q
Where are HSCs constantly renewed/ directed to differentiate into myeloid/ lymphoid progenitor cells?
A
Bone Marrow
10
Q
What are the 2 major types of progenitor cells that HSCs differentiate into?
A
Common Myeloid/ Lymphoid
11
Q
What progenitor cell gives rise to Red blood cells/ Megakaryocytes (platelets)/ Granulocytes/ Monocytes?
A
Common Myeloid Progenitor Cell
12
Q
What are 4 types of myeloid cells?
A
Granulocytes/ Monocytes/ Macrophages/ Dendritic cells
13
Q
Are myeloid progenitor cells related to innate or adaptive immune system:?
A
Innate
14
Q
Are lymphoid progenitor cells more innate or adaptive?
A
Adaptive (both)
15
Q
What progenitor cell gives rise to White blood cells/ B + T lymphocytes/ Innate lymphoid cells/ Natural Killer cells?
A
Common Lymphoid Progenitor Cell
16
Q
What progenitor cell gives rise to RBCs?
A
Myeloid
17
Q
What progenitor cell gives rise to WBCs?
A
Lymphoid
18
Q
What progenitor cell gives rise to Platelets?
A
Myeloid
19
Q
What progenitor cell gives rise to Granulocytes?
A
Myeloid
20
Q
What progenitor cell gives rise to Monocytes?
A
Myeloid
21
Q
What progenitor cell gives rise to Macrophages?
A
Myeloid
22
Q
What progenitor cell gives rise to B/T Lymphocytes?
A
Lymphoid
23
Q
What progenitor cell gives rise to Natural Killer Cells?
A
Lymphoid
24
Q
What kind of cell can both myeloid/ lymphoid progenitors give rise to?
A
Dendritic Cell
25
What is the precursor for platelets? (myeloid)
Megakaryocytes
26
What are the 3/4 types of granulocyte?
Neutrophil/ Basophils/ Mast cells/ Eosinophils
27
What granulocyte is associated with inflammation/ allergies?
Basophils/ Mast cells
28
What granulocyte is associated with antiviral/ antiparasitic activity?
Eosinophils
29
What are the 4 main types of cells that develop from common myeloid progenitor cells?
Erythrocytes/ Monocytes/ Granulocytes/ Megakaryocytes
30
What granulocyte causes direct harm to pathogens?
Neutrophils
31
How do the different granulocytes differ?
granule staining/ protein content + function
32
What do Neutrophils/ Eosinophils/ Basophils/ Mast cells have in common?
granules = granulocytes
33
What are 3 kinds of molecules produced by Neutrophils?
Proteases/ Antimicrobial proteins/ Histamine
34
What kind of molecule is Elastase?
Protease
35
What is the function of Elastase (protease)?
Tissue Degradation
36
What is an example of an antimicrobial protein (produced by neutrophils)?
Defensins
37
What is the role of Histamine?
Inflammation
38
What are the 3 types of molecules produced by Eosinophils?
Cationic proteins/ Cytokines/ Chemokines
39
What is the role of cationic proteins?
disrupt ion flow/ induce ROS formation
40
What is an example of a cationic protein?
Eosinophil Peroxidase
41
What is the relation of Eosinophils to the innate immune system?
Cytokines/ Chemokines
42
What kind of molecule is Interleukin?
Cytokine = Eosinophil
43
What kind of molecules are IL-8/ RANTES/?
Chemokine = Eosinophil
44
What is the function of chemokines?
attract leukocytes
45
What is the function of cytokines?
modulate adaptive immune responses
46
What are the 3 types of molecules produced by basophils/ mast cells?
Cytokines/ Lipid mediators/ Histamine
47
What molecules produce Histamine?
Neutrophils/ Basophils
48
What molecules produce Cytokines?
Basophils/ Eosinophils
49
What kind of molecule is Leukotriene?
Lipid Mediator
50
Why are lipid mediators important?
regulation of inflammation
51
What cells have phagosomes/ lysosomes in them?
Monocytes/ Macrophages/ Dendritic cells
52
What is the precursor for Macrophages?
Monocytes
53
What do monocytes differentiate into?
Macrophages/ Dendritic Cells
54
What cells function to repair/ remodel/ destroy pathogens/ present antigens?
Macrophages
55
What cells are known as "ingesters" of antigens?
Dendritic cells
56
What cells present antigens to naive T lymphocytes for initial activation?
Dendritic cells
57
What are professional antigen-presenting cells?
Monocytes (Macrophages/ Dendritic cells)
58
What 2 cells are specialized for phagocytosis?
Macrophages/ Neutrophils
59
What cells can present antigens to T cells via MHC molecules?
Macrophages
60
What cell is the most potent antigen-presenting cell for activating naive T cells?
Dendritic cells
61
What happens after immature dendritic cells capture an antigen?
mature/ migrate out of location to another to present antigen to T cells
62
What kind of proteins do professional antigen-presenting cells secrete?
proteins that attract/ activate other immune cells
63
How do professional antigen-presenting cells internalize pathogens?
phagocytosis
64
What do professional antigen-presenting cells do to internalize pathogens?
digest pathogenic proteins to peptides
65
How do antigen-presenting cells present peptide antigens on membrane surfaces?
MHC II molecules
66
What cells upregulate costimulatory molecules required for optimal activation of T helper cells?
professional antigen-presenting cells
67
What are the 3 main cell types that develop from common lymphoid progenitor cell?
B/T lymphocytes/ NK cells
68
Although lymphocytes appear similar, what makes them different?
Clusters of Differentiation = CD molecules on surfaces
69
Why are CD proteins important?
signal transduction
70
What CD molecule binds to MHC class II molecules?
CD4
71
What CD molecule binds to MHC class I molecules?
CD8
72
What type of cell is CD4 on?
T-helper
73
What type of cell is CD8 on?
T-cytotoxic
74
What does MHC do?
present antigen to lymphocyte
75
What would you find on T-helper cell membrane?
TCR/ CD4 molecule
76
What would you find on T-cytotoxic cell membrane?
TCR/ CD8 molecule
77
What would you find on B cell membrane?
BCR
78
What does the CD4 molecule do?
binds T helper cell to the antigen to hold antigen stable within the receptor
79
What is the state of newly formed B/T cells prior to activation?
Naive
80
What happens when naive lymphocytes interact with antigen?
proliferate and differentiate
81
What is the term for lymphocytes in an active role?
Effector cells
82
What is the term for the lymphocytes that persist in host and respond faster/ efficiently if re-challenged?
Memory cells
83
How many copies of BCR are on B cells/ why?
multiple of same receptor- stronger interaction
84
What are sets of genes that code for cell surface proteins essential for the immune system to recognize foreign molecules? (present molecule)
Major Histocompatibility Complexes = MHC
85
What cells have MHC I on them?
nucleated cells - neutrophils/ platelets NOT RBCs
86
What cells have MHC II on them?
antigen-presenting cells = dendritic cells/ phagocytes/ B cells
87
Where is blood cell formation during embryogenesis?
shifts site to site
88
Where do HSCs populate postnatally?
Bone Marrow
89
How do HSCs self-renew?
process takes time/ varies with host/ different stages differentiation (emergence/ maturation/ expansion)
90
B cells develop in contact with what cells?
Stromal cells of the bone marrow
91
What do stromal cells do?
facilitate HSC proliferation/ direct migration/ stimulate differentiation
92
Where do T cells initially develop?
Bone Marrow
93
Where do T cells migrate to develop to full maturity?
Thymus
94
What directs stepwise changes in thymocytes?
microenvironment of thymic cortex/ medulla
95
What drives positive/ negative selection?
TCR affinity of binding with MHC-peptides
96
What happens when thymocytes TCR's bind self MHC-peptide complexes with TOO HIGH affinity?
thymocytes induced to die
97
What is it called when thymocytes TCR's bind self MHC-peptide complexes with TOO HIGH affinity/ cell induced to die?
negative selection
98
What is the result of negative selection on thymocytes?
cell induced to die
99
What is it called when thymocytes bind self-MHC/peptide complexes with INTERMEDIATE affinity?
positive selection
100
What happens to thymocytes with the positive selection?
mature/ migrate to thymic medulla
101
Where does positive/ negative selection occur?
cortex of thymus
102
Where is the immune response initiated?
secondary lymphoid organs
103
Where do lymphocytes encounter antigens/ become activated/ undergo clonal expansion/ differentiate into effector cells?
secondary lymphoid organs
104
What are the 4 secondary lymphoid organ areas?
Lymph nodes/ Spleen/ Mucosa-associated lymphoid tissue = MALT/ gut
105
How are the secondary lymphoid organs connected to one another?
blood/ lymphatic circulatory systems
106
What is a network of vessels filled with lymph from plasma?
Lymphatic system
107
What is a protein-rich fluid?
Lymph
108
What is the fluid component of blood?
Plasma
109
What are the 2 most highly organized secondary lymphoid organs?
lymph nodes/ spleen
110
Where is B cell activity in secondary lymphoid organs?
cortex
111
Where is T cell activity in secondary lymphoid organs?
paracortex
112
How is B/T cell activity separated in secondary lymphoid organs/ lymph nodes?
microenvironment- cortex/ paracotex
113
What is the innermost lymph node?
medulla
114
Where are macrophages/ dendritic cells found?
medulla
115
What enters secondary lymphoid organ through the afferent vessel?
antigen
116
How do naive lymphocytes enter secondary lymphoid organs?
High Endothelial Venule = HEV
117
How do lymphocytes exit secondary lymphoid organs?
efferent vessel
118
What are the 3 parts of lymph nodes?
cortex/ paracortex/ medulla
119
What cells are found mostly in the follicles (cortex) of lymph nodes?
B cells
120
What cells are found mostly in the paracortex of lymph nodes?
T cells
121
What cells are mostly found in the medulla of lymph nodes?
Macrophages
122
What is the outer layer of lymph nodes called?
Cortex
123
What do lymphoid cells do during activation events?
actively migrate towards each other for required interactions
124
What guides T cells/ APCs toward activation interactions?
FRCC = Fibroblastic Reticular Cell Conduit
125
Where does differentiation into effector cells take place?
Follicles of secondary lymphoid organs
126
Where are dendritic cells arranged in follicles in lymph nodes?
cortex
127
Where are the follicles of B/ APC (dendritic) cells in the lymph nodes?
follicles = in cortex
128
Where do B cells further mature/ undergo clonal expansion?
germinal centers (follicles/ cortex)
129
What happens in germinal centres?
B cells further mature/ antigen affinity increased/ class switching occurs
130
What secondary lymphoid organ is the first line of defence against bloodborne pathogens?
spleen
131
What are red blood cells compartmentalized into in the spleen?
red pulp
132
What are white blood cells compartmentalized into in the spleen?
white pulp
133
What is the name of the specialized region of macrophages/ B cells that borders the white pulp?
Marginal Zone
134
What is an important layer of defence against infection at mucosal/ epithelial layers?
MALT = mucosa-associated lymphoid tissue
135
What organizes responses to antigens that enter mucosal tissue?
MALT
136
What is the network of follicles/ lymphoid microenvironments associated with the intestines?
GALT= gut=associated lymphoid tissue
137
What are the 4 secondary lymphoid tissues?
lymph nodes/ spleen/ MALT/ GALT
