2. IMMUNOLOGY Flashcards
1
Q
purpose of immune system
A
discriminate self from non-self
2
Q
what r the 2 types of non specific defence mechanisms and give 2 examples for each
A
physical: skin, cilia
chemical: sweat, tears
3
Q
What r the two components of a general immune response
A
inflammation and complement
4
Q
where r complements produced and where can they be found when inactivated
A
liver
circulate in blood
5
Q
what r the 2 functions of a complement
A
marks pathogens for destruction
clumps together lots of antigens
6
Q
what is the function of inflammation (2 things- steps, same point)
A
increase blood flow to an area
this brings immune cells to the site of infection
7
Q
name the three types of lymphoid organs
A
primary, secondary, tertiary
8
Q
what happens at primary lymphoid organs (general)
A
where leukocytes r synthesised
9
Q
what happens at secondary lymphoid organs (general) and what does this mean for naive cells
A
leukocytes monitor areas which allows naive cells to interact with antigens
10
Q
what r tertiary lymphoid organs, where do they form and in response to what
A
collections of immune cells that form in non-lymphoid tissues in response to local chronic inflammation
11
Q
what r the two primary lymphoid organs
A
bone marrow and thymus
12
Q
what is the bone marrow the site of (2)
A
site of immune cell synthesis and site of B cell maturation
13
Q
what is the thymus the site of
A
site of t cell maturation
14
Q
name the secondary lymphoid organs (3)
A
lymph nodes, spleen and mucosal associated lymphoid tissues (MALT)
15
Q
example of MALT
A
eg Peyer’s Patches in the small intestines
16
Q
what do secondary lymphoid organs involve the formation of
A
germinal centres
17
Q
what two cells do germinal centres produce (2)
A
produces long-lived antibody secreting plasma cells and memory B cells
18
Q
what are the lymph nodes the site of (1)
A
site of dendritic cell, B and T cell interactions
19
Q
what is the spleen the site of removal of (2)
A
site of removal of RBCs and antibody coated bacteria
20
Q
where r B cells found in lymph nodes
A
lymphoid follicles in cortex
21
Q
where r T cells found in lymph nodes
A
paracortex
22
Q
what cell does a dendritic cell interact with in the lymphatics and how do they enter and what with
A
interact with naive CD4+ cells to active them in the paracortex
enter with antigen in afferent lymphatics
23
Q
what happens to activated B and T cells in lymphatics (2)
A
T cell differentiate into effector or memory cells
B/T cells exit via lymphatics
24
Q
what is the general structure of the spleen
A
red and white pulp
25
function of red pulp
mechanically filtrates the RBCs
26
function of white pulp (1)
activates humoral and cell mediated immune response
27
what type of immune response is humoral immunity (1) and what does it involve (2) and what for (1)
adaptive immune response
involves B cells and antibodies for extracellular pathogens
28
what type of immune response is cell mediated immunity, (1) what does it involve (1) and what for (1)
adaptive immune response
involves mature T cells for intracellular pathogens
29
Why is the adaptive system required? (2)
1. innate immunity can be evaded
2. memory for faster response to same antigen
30
what r germinal centres rich in
B cells
31
what r PALS rich in and what does it stand for
(periarteriolar lymphoid sheath) r rich in T cells
32
when r tertiary lymphoid organs present and give an example (1)
present pathologically due to chronic inflammation eg primary chronic infection
33
what two lymphoid organs have germinal centres
secondary and tertiary
34
define Haematopoiesis
production of all the cellular components of blood and blood plasma
35
recall Haematopoiesis pathways
find picture
36
compare receptors for innate and adaptive immunity and give 2 examples for adaptive
innate= broad
adaptive= highly specific (b and t cell receptors)
37
compare onset for innate and adaptive immunity
innate= fast
adaptive= slow
38
compare amplification for innate and adaptive immunity
innate= no
adaptive= yes
39
compare duration for innate and adaptive immunity
innate= short
adaptive= long
40
compare self discrimination for innate and adaptive immunity
innate= not as good
adaptive= good
41
compare memory for innate and adaptive immunity
innate= none
adaptive= yes
42
compare regulation for innate and adaptive immunity
innate= not as controlled
adaptive= highly regulated
43
what two things can innate cells recognise and with what?
PAMPs and DAMPs
with PRRs
44
what does PAMPs and DAMPs and PRRs stand for
pathogen/damage associated molecular pattern
pattern recognition receptors
45
what r the two types of PRRs
membrane bound PPRs and cytoplasmic (free) PRRs
46
example of membrane bound PRR (2)
Toll like receptors and C-type lectin receptors
47
example of cytoplasmic bound PRR (1)
NOD-like receptor
48
define pattern recognition receptors, what is their origin and how is their conservation
receptors from germline with a great degree of evolutionary conservation
49
which TLRs r intracellular and what do they detect
TLR 3, 7, 8, 9
detect nucleic acids from intracellular pathogens (viruses and bacteria)
50
what TLRs r extracellular
all except 3, 7, 8, 9
51
How do TLRs work (4 steps)
1. binds to PAMP
2. secondary messengers generated in cell
3. secretion of inflammatory mediators (IL1,12, TNFa)
4. this stimulates activity of innate immune cells
52
what cells r TLRs found on
macrophages, dendritic cells and neutrophils (all APCs)
53
what is the PAMP TLR 2 recognises and where is this PAMP present
lipoteichoic acid
gram + bacteria and mycobacteria eg TB
54
what is the PAMP TLR 3 recognises and where is this PAMP present
double stranded RNA of viruses
55
what is the PAMP TLR 4 recognises and where is this PAMP present
lipopolysaccharide on gram - bacteria, viruses
56
what is the PAMP TLR 5 recognises and where is this PAMP present
flagellin on flagellated bacteria
57
what is the PAMP TLR 7/8 recognises and where is this PAMP present
single stranded RNA on viruses, bacteria
58
what is the PAMP TLR 9 recognises and where is this PAMP present
double stranded unmethylated DNA on viruses, bacteria and protozoa
59
what is significant about TLR 10
only present in humans
60
name the 7 innate cells (think TELEMANN)
dendritic cells
macrophages
neutrophils
basophil
eosinophil
mast cells
NK cells
61
why r dendritic cells important for immune responses
connects the innate and adaptive immune responses
62
origin of dendritic cells
mesenchymal origin
63
where can dendritic cells be found generally
in tissue that has contact with outside environment: skin, nasal lining, stomach and intestines
64
main dendritic cell and location (2)
interstitial dendritic cells (present in bone marrow and blood)
65
4 functions of dendritic cells
phagocytic, antigen presenting, cross presentation, cytokine production
66
What is cross presentation and explain dendritic cell cross presentation
Presentation of exogenous antigens via MHC by a APC
Dendritic cells present exogenous antigens in the context of MHC II to activate T cytotoxic cells
67
what 3 things can dendritic cells recognise
cytokines, PAMPS and DAMPs
68
characteristics of mature dendritic cells (5)
increased MHC II expression
increased secretion of pro-inflammatory cytokines
decreased phagocytic capacity
increased CCR7 expression
increased glycolysis
69
what is CCR7
chemokine receptor that guides DCs to secondary lymphoid organs
70
3 functions of macrophages
phagocytosis, antigen presentation and cytokine secretion
71
appearance of macrophage nucleus (3) and what do its lysosomes contain (1)
round single nucleus often with a small indentation
peroxidase
72
where r macrophages derived from (2)
blood monocytes or as tissue resident macrophages
73
where r tissue resident macrophages derived from and how do they persist
derived from yolk sac/ foetal liver during development
persist in tissues via self renewal
74
what r the identifiers of macrophages (2)
CD14+ and CD 40+
75
3 principle cells of chronic inflammation
macrophages, plasma cells, lymphocytes (T and B)
76
what r macrophages activated by (1)
INF gamma (IT IS i NOT t)
77
what can macrophages produce and give 3 examples
cytokines: TNF-alpha, IL-1 and IL-12
78
what is TNF alpha
a pro-inflammatory molecule
79
what is opsonisation and what two things can bind?
marking for phagocytosis by antibody and complement
80
explain the steps of opsonisation for antibodies
1. antibody binds to pathogen via their Fab region
2. macrophages have Fc receptors that bind to the antibody
3. this allows for phagocytosis of the bacteria that the antibody has bound to
81
explain steps of opsonisation for complement
1.antibody binds to pathogen via their Fab region
2. complement binds to antibody Fc region to form a complex
3. macrophages have complement receptors that recognise this complex which is then phagocytose
82
what is the most abundant leukocyte and what %
neutrophils 70
83
what do neutrophils secrete to kill pathogens
secretes superoxides which r toxic
84
What r the contents of neutrophils (2)
have 2 main intracellular granules: primary and secondary lysosomes
85
what 2 types of infections r neutrophils raised in
bacterial, bacterial pyogenic infections
86
two methods neutrophils use to kill pathogens
respiratory burst and phagocytosis
87
what is the principle cell of acute inflammation
neutrophils
88
what chemokine attracts neutrophils to site of infections and what two functions does this have
IL 8- role in neutrophil production and recruitment
89
example of polymorphonucleur cells and where can these be found
Barr body: present in female neutrophils
90
what is the GENERAL lifespan of neutrophils (gist)
short life
91
explain the steps of neutrophils movement in acute inflammation
1. neutrophils attracted by IL 8
2. E-selectin (adhesion molecule) on capillary endothelium is activated by IL-1 and TNF-alpha from damaged cells and binds to the CD15 glycoprotein on neutrophils in blood
3. neutrophils slow down and roll along endothelium lining
4. ICAM-1 on endothelium binds to intern on neutrophil, causing it to stop
5. diapedesis: neutrophil squeezes through the endothelium (holes made by C3a, C5a, chemokine, histamines and prostaglandins)
92
location of immature and mature basophils
immature= bone marrow
mature= circulating in blood
93
what activates basophils
IgE cross linking with its affinity IgE-Fc receptors (Fcε)
94
what three substances do basophils secrete
histamine, serotonin and heparin
95
what medical condition is basophils important in and give 4 examples
hypersensitivity reactions
hay fever, anaphylaxis, asthma, tropic dermatitis
96
where can basophils not go and what cells do this instead?
egress into tissues, mast cells
97
what 1 type of infection do eosinophils deal with
parasitic
98
what do eosinophils secrete and give three examples
release cationic granules eg major basic protein, ROS and eicosanoids
99
alternative name for granulocytes
polymorphonucleur cells
100
three granulocytes (BEN acronym)
basophil, eosinophil, neutrophil
101
what r the 3 main professional phagocytes
neutrophils, macrophages, dendritic cells
102
what type of killing mechanism is used in phagocytosis
oxygen dependant mechanism
103
what does a combined phagosome and lysosome form
phagolysosome
104
what two substances r released phagolysosomes to kill pathogens and what condition is maintained and why this condition
granzyme B and azurophillic granules and a low pH to ensure optimum conditions for destruction of pathogens
105
what is the MAIN oxygen dependant mechanism for killing
respiratory burst
106
explain the 5 steps of resp burst
1. electrons pumped into phagolysosome by NOX 2
2. electrons combine with molecular oxygen to make a superoxide
3. hydrogen and chloride ions are co-transported in
4. H+ combined with superoxide to make peroxide
5. peroxide combines with chloride ions to make HOCL (catalysed by MPO) which is bactericidal
107
what two reactions r mast cells present in
parasitic infection and allergic reactions
108
at what surfaces can mast cells be found
at mucosal surfaces
109
what is essential for massst cell development
stem cell factor
110
what r mast cells activated by
IgE binds to allergen then mast cell is activated via Rc receptor 1 (immune complex formed with IgE crosslinking Fcε R1)
111
what do mast cells secrete when they degranulate (5)
histamine, TNF alpha, IL 4 and 13 and lipid mediators
happy technicians found 13 lipid mediators
112
what does histamine do (2)
increase vascular permeability
smooth muscle contraction
113
what does IL 4 and 13 promote (2 things- be careful)
promotes Th2 differentiation
promotes IgE production
114
what does TNF alpha do (1)
promotes tissues inflammation
115
what do the lipid mediators prostaglandin and leukotrienes do (4)
increases vascular permeability
smooth muscle contraction
stimulates mucus secretion
chemoattractants for immune cells
116
where can NK cells travel (2)
blood and tissues
117
marker for NK cells (1)
CD 16+
118
what is the unique killing mechanism for NK cells
antibody-antigen dependant cellular cytotoxicity (ADCC)
119
how do NK cells recognise self and non-self
recognise self and non-self by the presence of MHC I on cell surfaces
120
what cells do NK cells activate, what do these do and how
cytotoxic T cells- which then act on tumor cells
NK cell cytokine production
121
explain the 3 steps of ADCC
1. IgG binds to surface antigens on the pathogen-infected or cancer cells
2. NK cells have Fc receptors (CD 16) that recognise that antibody Fc region
3. this cross linking triggers degranulation of granules that contain perforin and granzymes that induce apoptosis and cell death
122
how r virally infected cell identified by NK CELLS (2 step answer)
viral proteins expressed on the surface of cells during viral replication become antibody targets. Antibodies bind to this and NK cells can recognise the Fc region of the antibodies
123
how r cancer cells identified by NK cells
cancers down regulate MHC I mediated antigen presentation so when NK cell receptors detect low levels of MHC I on cell surfaces, they become activated and try to kill the cancer cill
124
what r the three main APCs and what do they all present in the context of what
macrophages, B cells and dendritic cells
all present exogenous antigens in the contact of MHC II
125
what is the most effective/ potent APC
dendritic cells
126
where do dendritic cells egress to
egress to secondary lymphoid organs
127
which cells can present MHC I
all nucleated cells (so not RBCs)
128
what does MHC stand for, what is it and what is its major role
major histocompatability complex
cell surface glycoprotein
presents antigens to T cells
129
where r MHCs coded for
chromosome 6
130
where are exogenous antigens processed in the cell and presented in which context
exogenous antigens are processed in the endoplasmic reticulum and are presented in context of MHC II
131
where r endogenous antigens processed and presented by
endogenous antigens r processed in endolysosomal compartment and are presented in context of MHC I
132
what forms an immune synapse (2)
a APC bound to a T cell
133
what three things do immune synapses require to be successful for a response to be generated
1. primary receptor binding eg TLR to MHC II
2. co-stimulatory molecules binding (co-receptors interacting on the bound DC and T cell in number 1)
3. appropriate cytokines being released
134
what happens to a T cell on initial encounter with a new antigen
T cells will differentiate into memory or effector T cells
135
what r the two adaptive immune cells
B and T cells
136
what is the identifying T cell marker and what is its function
CD 3- starts intracellular signalling which activates the T cell
137
can T cells express CD 4 and 8 and what happens to this ability after thymic education
can express both but thymic education leads to only 4 or 8 being retained not both
138
what r the three generic types of T cells
naive, effector or memory
139
what is a naive T cell
not encountered any antigens before
140
what is the T cell marker of activation
CD 25
141
what is memory and naive T cell identifier
memory= CD 45RO+
naive= CD45RA+
142
how do T cells recognise antigens and what is the exception to this
MHC binds to T cell receptors
exception= superantigens
143
what 4 things can (effector) T cells differentiate into after activation and what 2 factors does this depend on
T helper cells (1, 2, 9)
TfH (follicular helper cells)
depends on transcription factors and cytokine stimulation
144
what cell induces apoptosis in virally and cancer infected cells and what type of antigen is this
T cytotoxic cells
endogenous antigen
145
what is the marker for cytotoxic T cells
CD 8+
146
what two substances do cytotoxic T cells release to kill cells
perforin and granzymes
147
function of perforin
pore forming cytolytic protein that allows salt and water to enter cells and causes them to lyse
148
function of granzymes
proteases which initiates DNA degradation and apoptosis
149
how do T cytotoxic cells cause apoptosis (2 steps)
1. Tc cells expresses Fas ligand which binds to Fas on target cells
2. which activates caspase cascade to cause apoptosis
150
what MHC does T cytotoxic cells detect
MHC I
151
once activated what do cytotoxic T cells turn into (2)
effector or memory cells
152
marker for T helper cells
CD 4+
153
what is T cell polarisation and give two examples
antagonistic action of T helper cells eg Th1 and Th2 and Th17 and Treg
154
what do Th17 and Tregs do
17= inflammation
Reg= tolerance
155
what type of adaptive immunity do Th1 cells support
cell mediated
156
what cells Th1 regulate (4)
monocytes, macrophages, NK and cytotoxic T cells
157
overall action of Th1
eliminates cellular antigens
158
what type of immunity do Th2 cells support
humoral immunity
159
what cells Th2 regulate (3)
eosinophils, basophils, mast cells
160
overall action of Th2 (3)
stimulate B cells, increase IgE antibody production by class switching B cells
161
what r Tregs
principle cells in peripheral immune tolerance (tolerance)
162
what is the key cytokine with mass anti-inflammatory action
IL 10
163
where is Th17 located
mucosal membranes
164
what is the principle cytokines of Th17 cells and what is its action
IL17
induces immune cells to produce IL 8
165
three types of B cells
can be naive, effector or memory
166
whats the mature B cell marker
CD 20
167
what is the alternative name for effector B cells
plasma cells
168
what 3 steps happens when memory B cells encounter their specific antigen?
1. activated
2. undergoes proliferation
3. begin secreting IgG
169
where does B cell activation occur
secondary lymphoid organs in cortex of lymph nodes mostly
170
what r the two ways that B cells can be activated
1. activated directly by internalising the antigen
2. activated indirectly via APCs
171
characteristic of B cells that r directly activated by antigens (3)
short lived B cells
rapid production
IgM releasing
172
characteristic of B cells indirectly activated (3)
long-lived plasma cells
release IgG, E or A
higher affinity
173
where do activated B memory cells go after an infection has been dealt with
back to secondary organ or to bone marrow
174
where do B cells migrate to and from after activation
migrate from their lymphoid follicles to newly formed germinal centres
175
what three changes do B cells undergo after activaation
somatic hypermutation, clonal expansion, class swtiching
176
how is B cell affinity tested after somatic hypermutation? What happens to those with high affinity
Dendritic cells in germinal centres present the same antigen to the B cell to test its affinity- positive selection occurs for B cells with high affinity
177
what is somatic hypermutation
point mutations in antibody which allows higher affinity binding to antigen
178
what does the Fab region of an antibody bind to
epitope of the antigen
179
what r Fab regions of an antibody determined by?
determined by a process called VDJ recombination during maturation in the bone marrow
180
what is agglutination
using antibodies to cluster and bind pathogens together
181
functions of antibodies 4
neutralisation of toxins
agglutination
opsonisation of pathogens
complement activation via the classical pathway
182
what does the antibody Fc region stand for and what dose it bind to
fragment crystallisable region
binds to Fc receptors on immune cells surfaces
183
what does the constant region of the antibody determine 2
antibody type and therefore effector function
184
what r the 3 structural ways of labelling antibodies
1. variable and constant region
2. Fab and Fc region
3. light and heavy chains (constant region= only heavy, variable= light and heavy)
185
what is colostrum
initial part of breastmilk
186
what antibodies does colostrum contain (3 and which one is the principle one)
IgA, IgM and IgG but IgA is the principle antibody
187
what is lymphocytosis and what 2 types of infection cause this
raised lymphocyte levels
viral infections and intracellular bacterial infections but these r less common eg TB)
188
where is IgA normally present in the body (3)
coats mucosal surfaces, colostrum and coats neonate gut
189
form of IgA antibody
dimer
190
form of IgM antibody
pentameric
191
what antibody has highest capacity to activate complement
IgM
192
what antibody is most abundant in blood
IgG
193
how specific is IgM
not entirely specific to antigen
194
how specific is IgG
highly specific
195
which antibody can cross the placenta
IgG
196
what antibody is important in secondary responses
IgG
197
how many subclasses does IgG have?
4
198
what cells does IgE bind to and how
mast cells and basophils
via Fc receptors
199
tell mw about IgD function
not known
200
what infections r IgE antibodies important for (2)
allergy and helminth
201
what is the first antibody to respond to antigen exposure
IgM
202
what happens to IgG levels in secondary response (2)
IgG levels increase rapidly and to a high level
203
what is hypersensitivity
undesirable response to antigenic, allergenic or self material
204
condition for hypersensitivity
requires pre-sensitisation state of the host
205
what type of reaction is T1 and give an example
anaphylactic eg anaphylaxis
206
what type of reaction is T2 and give an example
antibody-mediated eg pernicious anaemia
207
what type of reaction is T3 and give one example
immune complex eg farmer's lung
208
what type of reaction is T4 and give one example
T cell mediated eg TB
209
mechanism of T1 reaction and what is released
cross linking of antigen to IgE on mast cells/ basophils causes massive degranulation therefore, massive release of histamine
210
what makes up a membrane attack complex (5) and what does a MAC do?
C5b, C6, C7, C8, C9, creates hole in bacterial cell membrane
211
mechanism in T2 reaction and what are the two methods that this causes cell destruction
igM/ igG binds to self antigen on cell surface= cell destruction by the membrane attack complex and cellular mechanisms
212
mechanism of T3 reaction and what does it cause
free IgG/IgA binds soluble antigen forming a circulating immune complex which causes inflammation
213
mechanism of T4 reaction (include second exposure)
primary exposure: Th1 is activated by APCs and forms memory T cells
secondary exposure: memory T cell encountering antigen again, they activate macrophages causing tissue damage
214
what cell is T4 reactions mediated by
Th1- T helper cell 1
215
examples of T1 reaction 4
anaphylaxis
asthma
hay fever
dermatitis
216
examples of T2 reaction (4)
autoimmune haemolytic anaemia
goodpastures's syndrome
pernicious anaemia
RHEUMATIC FEVER
217
examples of T3 reaction (2)
systemic lupus eyrthematosus
post-streptococcal glomerulonephritis
218
examples of T4 reaction (4)
TB
graft vs host disease
MS
guillian-barre syndrome
219
what is anaphylaxis classed as medically
a medical emergency that can be fatal
220
what is treatment procedure for anaphylaxis (4)
1. ABCDDE
2. call help
3. remove trigger
4.IM 500mcg adrenaline
221
what is the treatment if there is no response to anaphylaxis treatment after 5 minutes
repeat IM adrenaline
222
what 3 things can cause autoimmunity to develop
thymic education failure (mismatch of immune tolerance)
failure of t regs (normally release IL 10)
CD4 activation against autoantigens
223
what does treatment for autoimmunity involve (2)
reducing inflammation
suppressing the immune system
224
2 examples of autoimmune conditions
SLE
MS
225
what is central tolerance- better definition?
B and T cell receptors r tested against see antigens
226
what 2 things happen to B cells in central tolerance that recognise self antigen
apoptosis or receptor editing
227
what happens to T cells in central tolerance
T cells undergo positive and negative selection (+ recognise MHC molecules and - test affinity to self)
228
what is peripheral tolerance and what cell tests this
peripheral tolerance= some low affinity self reactive T cells can escape the thymus to the periphery and r tested by dendritic cells.
229
what happens to identified faulty T cells in peripheral tolerance
undergo apoptosis or are converted to Tregs
230
4 features of autoimmunity
often relapsing remitting
damage/ destruction of tissues
altered organ growth/ function
generation of autoantibodies
231
what is primary immunodeficiency, what types of disorders and give an example
those born with intrinsic defects in their immune system
rare and mostly genetic disorders
eg SCID (where T and B cells lose functionality)
232
what is secondary immunodeficiency, what is it referred to as
acquired immunodeficiency and referred to as immunosuppression
233
define what occurs in immunosuppression
production is negated or blocked
234
what can induce secondary immunodeficiency? 2
drugs eg steroids
cancers of bone marrow and blood eg leukaemia
235
explain profound immunodeficiency regarding HIV and AIDs
HIV has a cell tropism for CD4+ which destroys them
once CD4 cell count is bellow 200 cells/uL there is profound immunodeficiency= defines development of AIDS
236
what is the principle of vaccination (5 key points, 1 definition)
controlled and safe exposure to a part of a pathogen that is immunogenic and will induce immunological memory with little to no harm to the host
237
what is negative phase related to vaccinations
period after initial antigen exposure where ones immunity is actually lower than before encountering the antigen
238
compare active and passive immunity negative phase
active= negative phase and passive= no negative phase
239
compare active and passive immunity boosters
booster effect on subsequent dose for active immunity but in passive, the antibodies r eliminated so there is no boost
240
what is the key cytokine for resolution of allergic inflammation
INF gamma
241
4 functions of IL4
IgE class switching
Th2 polorisation
promotes eosinophils to enter tissues and mucous secretions
activates B cells to differentiate into plasma cells
242
name all the pro-inflammatory cytokines (9)
1, 2, 3, 5, 6, 8, 12, TNF alpha, Interferon gamma
243
name all the anti-inflammatory cytokines (2)
4, 10
244
main source of IL1 and function
macrophages
induces fever
245
main source of IL2 and function
Th1 cells
stimulates growth and differentiation of T cells
246
main source of IL3 and function
activated T helper cells
stimulates differention and proliferation of myeloid pregenitor cells
247
main source of IL4 and function
Th2 cells
stimulates proliferation and differentiation of B cells
248
main source of IL5 and function
Th2 cells
stimulates production of eosinophils
249
main source of IL6 and function
macrophages and Th2
stimulates differentiation of b cells and induces fever
250
What is chemotaxis and what two things can do this
attraction and movement of macrophages towards a chemical signal
cytokines and chemokines
251
main source of IL8 and function
macrophages
neutrophil chemotaxis
252
main source of IL10 and function
th2 cells
inhibits th1 cytokine production
253
main source of IL12 and 2 functions
dendritic cells, macrophages, b cells (APCs)
activates NK cells and stimulates differentiation of naive T cells into Th1 cells
254
main source of TNF alpha and functions (2)
macrophages
induces fever, neutrophil chemotaxis
255
main source of Interferon gamma and function
th1 cells
activates macrophages and NK cells
256
what is a complement (3- what is it, where is it synthesised, what form does it circulate in)
an acute phase protein synthesised by the liver and circulates in an inactive form
257
name the three pathways of complement
classical, B lectin and and alternative pathway
258
what is the function of C3 convertase
cleaves C3 into C3a and C3b
259
what is the product of the 3 complement pathways
C3 convertase
260
what activates the classical pathways
antigen- antibody complex (IgM/G)
261
what activates the alternative pathways
when C3b in plasma directly binds to pathogen surfaces and activates the cascade
262
what activates the MB lectin pathway
activated by mannose binding lectin (MBL) binding on mannose on pathogen’s surface
263
what is mannose
mannose is a pathogen surface carbohydrate that is not present on human cell
264
what r the 3 main products of the complement pathways (3)
mainly C3a, C5a, C3b
265
what does C3b do
opsonises pathogens
266
what does C3a do (2)
inflammation and chemotaxis
267
what is CD3 a marker of?
signalling component of T cell receptor
268
what is CD4 a marker of? Where is this found (1) and what is its significance pathologically
co-receptors for MHC II
found on helper T cells
used by HIV to enter T cells
269
what is CD8 a marker of? Where is this found (2)
co-receptor for MHC I
found on subset of myeloid dendritic cells and on all T cells
270
what is CD14 a marker of?
surface marker for macrophages
271
what is CD16 a marker of?
bind to Fc portion of IgG antibodies
272
what is CD56 a marker of?
unique marker for NK cells
273
what is CD95 a marker of?
acts as FAS receptor, involved in apoptosis
274
main marker for a T reg cell
CD 28
275
four examples of immune based therapies
monoclonal antibodies, cytokines, IV immunoglobulins, immunosuppressive drugs
276
why r cytokines often the drug target for immunity
because cytokines regulate the immune system
277
what do HLAs stand for and compare to MHC
human leukocyte antigen
HLA r specific to humans only as other animals have MHCs but HLA is synonymous to MHC
278
which HLA associates correspond to MHC I (3)
A, B, C
279
which HLA associates correspond to MHC II (4)
HLA-DR, DQ, DP and DM
