Immunodeficency

Question 1

what are the principle function of the immune system

Answer 1

protect from infection.
multilayer defence system
network of pathogen recognition to detect which antigens are self.
effective intracellular communication
multiple mechanism to remove pathogen
self regulation.

Question 2

Is the innate immune system long term or short term

Answer 2

short term

Question 3

Is the adaptive immune system long term or short term

Answer 3

long term

Question 4

is the innate immune system specific or non specific

Answer 4

non-specific

Question 5

Is the adaptive immune system specific or non specific

Answer 5

specific.

Question 6

What are the 3 components of the innate immune system

Answer 6

PPR, Cellular, barrier and chemical mechanisms

Question 7

What are the 2 components of the adaptive immune system

Answer 7

cellular and humoral.

Question 8

Where are receptors in the innate system found.

Answer 8

On cells e.g. macrophages and dendritic cells.

Question 9

What are the major components of the innate immune system and what do they tell us.

Answer 9

detect the type of pathogen e.g. gram +ve or -ve, virus but not the specific pathogen
PRR-pattern recognition receptor.
antimicrobial peptides, cells, complement components, cytokines.

Question 10

Pattern recognition receptors include

Answer 10

TOL like receptors, NOD like receptors, Rigl like receptors, C type lectins, scavenger receptors.

Question 11

Antimicrobial peptides include

Answer 11

defensins, cathelin, protegrin, granulysisn, histatin, secretory leukoprotease inhibitors and probiotics.

Question 12

Cells

Answer 12

macrophages, dendritic cells, Nk cells, NK T cells, neutrophils, eosinophils, mast cells, basophils and epithelial cells.

Question 13

Complement component

Answer 13

classic and alternative complememnt pathways and proteins that bind complement components

Question 14

cytokines

Answer 14

Autocrine, paracrine, endocrine, cytokines and mediate host defines and inflammation as well as recruit, direct and regulate adaptive immune responses

Question 15

Function of humoural aspect of adaptive immune system

Answer 15

– Kill, neutralise and recognise pathogen.

– Deal with extracellular orgnaism

Question 16

What are the different types of T lymphocytes

Answer 16

Killer or cytotoxic T lymphocytes are able to kill.

Helper T lymphocytes secrete growth factors (cytokines) which control immune response: Help B lymphocytes and T lymphocytes (Helper T cells are target of HIV)
Organise other components of the immune system.
Deal with intracellular organism e.g virus.

Suppressor T lymphocytes may damp down immune response

Question 17

What is the function of antibodies

Answer 17

•	Neutralize bacteria
•	Agglutination 
•	Precipitation of dissolved antigens.
PHAGOCYTOSIS
•	Activate complement
CELL LYSIS

Question 18

What is the function of T cells.

Answer 18

• Cytotoxic t cells bind infected cell
• Perforin makes holes in cell membrane
• Infected cell is destroyed.

Question 19

Do B cells deal with intra or extracellular infection

Answer 19

extracellular

Question 20

Do T cells deal with intra or extracellular infection

Answer 20

intracellular.

Question 21

How does the innate immune system communicate with the adaptive

Answer 21

cytokines
cells in the innate system which have engulfed the pathogen will express cytokines which trigger the adaptive immune system- instruct CD4 to make T cells.

Question 22

define immunodeficiency.

Answer 22

• Clinical situations where the immune system is not effective enough to protect the body against infection

Question 23

Causes of secondary or acquired immunodeficiency.

Answer 23

stress
surgery/burns
malnutrition
Cancer
Immunosuppressive effect of drug- chemotherapy
irradiation
AIDS.

Question 24

Causes of primary immunodeficiency.

Answer 24

very rare- genetical

Question 25

What is IRAK deficiency

Answer 25

innate system IRAK is a toll like receptor recognises bacterial cell wall or viral component. IRAK through intracellular signalling produces NF-Kb (transcriptional factor)- needed to make cytokines

Question 26

What test determines the function of neutrophils

Answer 26

Nitroblue tetrazolium test. Incubate neutrophil with dye and it should take up the dye creating free oxygen radicals forming dark blue circles. This does not occur if defective.

Question 27

What type of genetic disorder is the defect in NADPH oxidase complex

Answer 27

X-linked- defect in how phagocytes work.

Question 28

How does NADPH oxidase complex work

Answer 28

NADPH- oxidase complex trasfers one hydrogen atom across the membrane This forms free oxygen radicals causes acidic conditions and a decrease in pH Acidic pH releases prteolytic enzymes to destroy the infection.

Question 29

Clinical symptoms of chronic granulomatous disease (CGD)

Answer 29

``` • Osteomyelitis- bone infection • Pneumonia • Swollen lymph nodes • Ginigivitis- (gum disease) • Non-malignant granulomas • Inflammatory bowel disease – Immune system tries to compensate for decreased neutrophils= secrete chemo/cytokines- so although they are immunodeficient also have overproduction of other mechanisms for coping resulting in IBD. ```

Question 30

What defects in the complement pathway may result in immunodeficiency

Answer 30

lack of a factor C1, C9- without a factor a pore cannot be created in the bacterial membrane.

Question 31

How to diagnose a lack of complement factor deficiency

Answer 31

* Sheep RBC don’t have anything to inhibit complement whereas human RBC do * Sheep RBC and patient serum- complement should activate and RBC should lysis.

Question 32

What types of infections of defects in B cells predispose you too.

Answer 32

respiratory infections | recurrent bacterial infection with pyogenic organisms.

Question 33

what cell type defect results in X-linked agammaglobulinaemia

Answer 33

Primary B cell deficiency

Question 34

Is X-linkes agammagloinaemia a recessive or dominant condition.

Answer 34

autosomal recessive.

Question 35

what immunoglobulins are deficient in X-linked agammaglobinaemia

Answer 35

``` IgA IgG (subclass deficency) ```

Question 36

Which cell type deficiency is worse- B or T cell

Answer 36

T cell- B cells also require T cell help.

Question 37

What are the common symptoms of T cell deficiency

Answer 37

• Symptoms are recurrent infection with opportunistic infections, bacteria, viruses,

Question 38

What is the name of the deficiency which has both B and T cell deficiency.

Answer 38

– Severe Combined Immunodeficiency (SCID) syndromes

Question 39

How do you treat SCID (severe combined immunodeficiency)

Answer 39

bone marrow transplant. Gene therapy- replace faulty gene using viral plasmid and patient stem cells, virus incorporates genome into patients.

Question 40

What are the primary T cell deficiencies

Answer 40

Severe combine immunodeficency syndromes (SCID) Adenosine deaminase deficency Purine nucleoside phosphorylase deficncncy MHC Class II deficencny WiskottAldrich Syndrome