The Immune System Flashcards
(176 cards)
1
Q
Role of lymph nodes
A
Filter fluids in collecting vessels
2
Q
4 lymphoid organs
A
- Spleen
- Lymph nodes
- Tonsils
- Thymus
3
Q
What occurs at the arterial end of the capillaries- state the direction of fluid
A
Filtration - fluid moves out
4
Q
What occurs at the venous end of the capillaries - state the direction of fluid
A
Reabsorption - fluid moves in
5
Q
How much excess fluid is drained OUT of the blood into the lymphatic system?
A
3L
6
Q
Why does fluid move out of the capillaries at the arterial end?
A
The hydrostatic pressure is greater than osmotic pressure
7
Q
Why does fluid move into the capillaries at the venous end?
A
The osmotic pressure is greater than the hydrostatic pressure
8
Q
What type of cells are lymph capillaries made from?
A
Endothelial cells
9
Q
2 unique structural modifications in the capillaries
A
- Cells overlap to create valves
2. Gaps in the wall to prevent leakage
10
Q
3 tunics of lymph collecting vessels
A
- Interna
- Media
- Externa
11
Q
What do lymphatic vessels in the skin travel with?
A
Superficial veins
12
Q
What do vessels in the deep lymphatic system travel with?
A
Deep arteries
13
Q
Which parts of the body drain into the right lymphatic duct?
A
- right arm
- right side of brain
- right side of thorax
14
Q
where does most of LHS of body drain into ?
A
Thoracic duct
15
Q
What veins does the lymph enter? (2)
A
- Subclavian vein
2. Internal jugular vein
16
Q
Does the lymph system have a pump?
A
No
17
Q
What type CT is there in lymphoid tissue?
A
Reticular
18
Q
Where in the lymphatic system are B cells stored?
A
Nodules
19
Q
2 distinct regions of the lymph node
A
- Inner medulla
2. Outer cortex
20
Q
Where does lymph enter the lymph nodes?
A
Afferent lymphatic vessels
21
Q
Where does lymph leave the lymph nodes?
A
efferent lymphatic vessels at the hilus
22
Q
4 types of tonsils
A
- Palatine
- lingual
- Pharyngeal
- Tubal
23
Q
Where does interstitial fluid collect?
A
Intercellular spaces
24
Q
Why is lymph slow moving and has a low pressure?
A
The lymphatic system does not have a pump
25
Which places is lymphoid tissue stored?
1. Most organs
| 2. Nodules
26
What is lymphoid tissue?
Immune tissue
27
Where are lymph nodules found?
Within lymph nodes
28
Function of lymph sinuses
allow macrophages to enter
29
Which area of the spleen contains the venous sinus, red cells and splenic cord?
Red pulp
30
What does the white pulp of the spleen contain?
Lymphocytes on reticular fibres
31
What hormones does the thymus secrete to make T cells immunocompetent?
1. thymosin
| 2. thymopentin
32
2 areas of the thymus
1. Dark staining cortex
| 2. Light staining medulla
33
Which area of the thymus contains densely packed lymphocytes?
Dark staining cortex
34
Role of Thymic corpuscle?
converts self-reactive T cells into immunosupressive T cells
35
Role of tonsils
gather inhaled/ingested pathogens
36
Which tonsil surrounds the auditory tube?
Tubul
37
Which tonsil is at the back of the nasopharynx?
Pharyngeal
38
Which tonsil is under the tongue?
Ligual
39
Where are the palatine tonsils?
Either side of the posterior oral cavity
40
What do viruses need to replicate?
A host
41
Do viruses contain any organelles?
No
42
How to viruses bind to the host cells?
Surface proteins that host cells recognise
43
Name a virus and disease which the virus dormant time can be decades
Chicken pox - shingles
44
What structure can bacteria form to act together?
Biofilms
45
Which type of bacteria have purple staining?
Gram +ve
46
describe the cell wall in gram -ve bacteria
Thin peptidoglycan wall
| Extra cell membrane - lipopolysaccharide
47
What is cellulitis an infection of?
The skin
48
Are fungi eukaryotes or prokaryotes?
Eukaryotes
49
Why are fungal infections hard to treat?
Because they have the same organelles as human
50
3 types of fungi
1. Yeast
2. Mould (pores)
2. Dimorphic
51
What is dimorphic fungi?
Fungi that can switch between types
52
Thrush, athletes foot and ringworm are all types of what infection?
Mild fungal infection
53
Parasite that lives outside of the body
Ectoparasite
54
Parasite that lives inside of the body
Endoparasite
55
Parasite that lives inside of another parasite
epiparasite
56
2 classes of human parasites
1. Protazoa
| 2. Helminths
57
What is the name of the protazoa that causes diarrhoea?
Giardia
58
Which human cell does malaria enter?
RBC
59
3 types of helminths
1. Trematodes
2. Nematodes
2. Cestodes
60
Name of helminth tapeworms
Cestodes
61
What diseases can cestodes cause:
1. Malnutrition
| 2. Malabsorption
62
How does a fluke enter a human body
By the skin
63
What is the smallest infective agent?
Prions
64
How do prions affect proteins
causes them to change their folding shape - becomes non-functional
65
What is microflora?
Microorganisms on the surface of the skin - preventing other bacteria from entering
66
Name 4 ways to recognise antibody binding
1. Enzyme
2. Collodial gold
3. Radioactive element
4. Fluorescent dye
67
Why is the indirect method using fluorescent dyes for immunohistochemistry not persistant?
The antibodies do not stay attached for long
68
What colour stain is produced with the indirect method of IHC using an enzyme?
brown
69
What antibody is biotinylated in IHC?
Secondary antibody
70
What is used to preserve a antibody staining?
Chemical fixatives
71
Why are chemical fixatives sometimes a problem?
Identification of the antibody binding is lost
72
Why is an isotyte antibody used during Immunohistochemistry?
To test for a false positive
73
During ELISA, why are the plates washed?
to remove unbound antibodies
74
Advantage of competitive ELISA
more specific
75
Do bacterial cells have a nuclear membrane?
No
76
What are the 70s bacterial ribosomes split into?
30s and 50s
77
What are the 80s mammalian ribosomes split into?
40s and 60s
78
What is an aerobic organism?
requires oxygen to grow
79
What is an anaerobic organism?
Doesnt require oxygen for growth
80
What is the name of an organism which can use oxygen for growth but also has anaerobic methods of energy production
Facultative
81
What are atypical bacteria?
Do not stain either gram +ve or -ve
82
Name 3 types of atypical bacteria
1. Mycoplasmas
2. Chylamadiae
3. Rickettsiae
83
How is DNA carried in bacteria?
Plasmids in the cytoplasm
84
Term that describes: medicine that inhibits the growth/destroys microorganism
Antibiotic
85
Term that describes: destructive/inhibiting growth of bacteria
Antibacterial
86
Term that describes: destructive/inhibiting growth of microorganisms
Antimicrobial
87
Term that describes: chemical liquid that destroys bacteria
Disinfectant
88
Term that describes: drug/substance which kills bacteria
Bactericidal
89
Term that describes: Capable of inhibiting the growth of bacteria
Bacteriostatic
90
Name of 2 types of antibiotics acting on the cell wall
1. beta lactams
| 2. Glycopeptides
91
Function of beta lactam
break cross links in peptidoglycan cell wall
92
Mechanism of action of penicillin
work on penicillin-binding-proteins on bacterial cell wall to weaken it and affect cell division
93
How do glcopeptides function?
inhibit peptidoglycan formation - prevention of joining dimers
94
Why cant glycopeptides work against gram -ve bacteria?
It is too large to penetrate through the lipopolysaccharide wall
95
Name a type of glycopeptide
Vancomycin
96
Where do lipopeptide antibiotic work?
Cell membrane
97
How do lipopeptide antibiotics work?
Depolarise the cell membrane
98
Which antibiotic acts on the 23s subunit of 50s ribosome?
Linezoid
99
Mechanism of chlorophenicol, macrolides and lincosamides (antibiotics)
Attach to 50s ribosomal unit - prevents AA chain forming
100
Which antibiotic prevents the attachment of mRNA to the ribosome?
Aminoglycosides
101
Role of tetracyclin antibiotics
Attach to 30s ribosomes - tRNA cannot bind to mRNA
102
3 Antibiotics acting on nucleic acid synthesis
1. Ramfipicin
2. Quinolones
3. Metranidazole
103
Role of ramfipicin
inhibits RNA polymerase
104
Role of Quinolones
Inhibits DNA gyrase - strands cannot reseal
105
Role of metranidazole
Attaches to DNA strand - causing breakage in strands
106
How does the antibiotic trimethoprim work?
Interferes with a metabolic pathway
107
What does trimethoprim inhibit?
dihydrofolate reductase - formation of folic acid
108
What is antibiotic prophylaxis
using antibiotics before surgery & chemotherapy to prevent infection
109
What is instrinsic resistance?
The entire species is resistant before the antibiotic has been introduced
110
3 types of gene transmission in bacteria
1. conjugation
2. transduction
3. transformation
111
Define a nosocomial disease
An infection not present or incubating prior to admittance to hospital - usually occuring 48 hours after admittance
112
What pathogen causes Hospital Acquired Pneumonia?
Bacteria
113
What is CAUTI
Cathetar associated urinary tract infections
114
What type of bacteria is E Coli?
Gram negative
115
What does sepsis cause?
Injury to own tissues & organs
116
What type of bacteria is MRSA?
Gram +ve
117
What 2 classes of antibiotics are MRSA resistant to?
Penicillin and cephalosporin
118
How does methicillin kill a bacterial cell, what organelle specifically?
It attaches to penicillin binding sites- weakening the cell wall.
119
How is MRSA resistant to all penicillins?
Penicillins all contain the beta lactam ring. Resistant strands modify the PBP so penicillins cannot attach.
120
What type of bacteria is C.diff?
Gram +ve
121
How is C.diff transmitted?
1. Orally
| 2. Through faeces
122
what does C.diff form?
Spores
123
Which enzyme identifies C.diff?
Glutamate dehydrogenase
124
2 types of toxin tests
1) ELISA
| 2) PCR
125
How can antibiotics be a risk factor for C.diff?
They alter gut flora - allowing C.diff to flourish & produce toxins
126
What is conservative treatment?
Avoiding invasive treatments - watchful waiting etc.
127
What antibiotics is glycopeptide resistant enterococci resistant to?
1) Vancomycin
| 2) teicoplanin
128
What type of bacteria does daptomycin work against?
Gram +ve
129
Define Vmax
Maximum velocity (rate) of reaction - at saturating [S]
130
Define Km
[S] at which rate if half of Vmax (maximum rate)
131
What Km will an enzyme have with low affinity for substrate?
high Km
132
Define necrosis
Tissue degeneration by lysosomal enzymes due to disease.
133
What does tissue repair inhibit?
Mast cell activation
134
Define dysplasia
Loss of normal architecture of cells
135
Define metaplasia
When tissues adapt to environmental stimuli by change in cell differentiation
136
What do cells differentiate to and from in the cervix?
columnar to squamous
137
What is well differentiated malignancy?
cells that closely resemble tissue of origin
138
What is atheroscleorosis?
Thickening and inelasticity of artery walls
139
Where are B and T cells produced, developed and matured?
Red bone marrow and thymus gland
140
3 secondary lymphatic organs
1. Spleen
2. Lymph nodes
3. Lymph nodules
141
Role of physical barriers in the body
prevent pathogen reaching epithelia
142
Define haematopoiesis
Formation of blood components
143
What are interferons produced by?
Lymphocytes, macrophages and fibroblasts which have been infected by a virus
144
3 types of interferons
1. Alpha
2. Beta
3. Gamma
145
Which pathogens do interferons work against?
Viruses
146
Which antimicrobial protein works by puncturing holes in the cell membrane?
Complement cascade
147
What 3 pathogens do M1 (classically activated macrophages) defend against?
1. Viruses
2. Bacteria
3. Protazoa
148
What is macrophage plasticity?
Macrophages behave differently depending on what protein they express.
149
What does PAMPS stand for?
Pathogen associated molecular patterns
150
What is an epitope?
The small component of an antigen which only initiates an immune response.
151
What are the 5 types of immunoglobins?
GAMED
152
How many polypeptide chains does an antibody have?
4
153
What 3 processes occur when the antigen binds at the variable region?
1) Neutralisation
2) Agglutination
3) Precipitation
154
In monoclonal antibody technique, what cells are taken from the mice?
Spleen
155
Which proteins are involved in complement?
C1-C9
156
which 3 factors are involved in complement?
1. Factor B
2. Facor D
3. Factor P (Properdin)
157
In terms of complement, which binding protein is involved in the lectin pathway?
Mannose binding protein
158
3 pathways of complement
1. Innate - lectin
2. Innate - alternative
3. Classical
159
What enzyme produces alpha gal residues?
alpha-1,3- galactose transferase
160
What is the name of the type of tolerance which is non-reactivity to an antigen that should cause an immune response?
Acquired tolerence
161
Where do Pre T cells develop self-recognition?
In the thymus
162
Which antibody isotype encourages mast cell degranulation?
IgE
163
Which immune cells are responsible for allergic contact eczema - type 4 hypersensitiivty?
T cells
164
Which antibody type induces type 1 hypersensitivity?
IgE
165
Biological effect of a chemokine in type 1 hypersensitivity
Attracts macrophages, neutraphils and monocytes
166
Which hormone relaxes bronchiole smooth muscle
Epinephrine/adrenaline
167
Which immune cells phagocyte when the parasite is too large to be engulfed by a phagocyte?
Eosinophil
168
2 methods of diagnosis for allergies?
1. Pinprick test
| 2. ELIZA - blood sample; IgE titre is taken
169
What cells undergo apoptosis in atopic dermatitis?
Keratinocytes - skin
170
Which antibody isotype cause type 2 hypersensitivity?
IgG
171
2 type 2 hypersensitivity diseases
1. Anaemia
| 2. Thrombocytopenia
172
In type 2 hypersensitivity, what do IgG antibodies attack?
RBC/platelets
173
What antibodies cause type 3 hypersensitivity?
IgG
174
In type 3 hypersensitivity why can only phagocytosis act?
The antigens are soluble
175
What response does type 3 hypersensitivity bring about?
Inflammatory
176
What is destroyed in coeliac disease?
Villi in intestine
