Clinical Immunology

Question 1

What chromosome are the HLA class 1 genes on?

Answer 1

Chromosome 6

Question 2

Name the HLA class 1 groups

Answer 2

HLA-A, HLA-B, HLA-C

Question 3

Name the HLA class 2 types

Answer 3

HLA-DP, HLA-DQ, HLA-DR

Question 4

How man HLA alleles are there?

Answer 4

Hundreds. 1 in 70 million chance of having identical match.

Question 5

Explain direct recognition in donor rejection

Answer 5

Donor APCs migrate to lymph nodes where they are recognised by t- cells that are stimulated by HLA proteins on APC cell surface = ALLOREACTIVE RECIPIENT T-CELLS

Question 6

Explain indirect recognition in donor rejection

Answer 6

Proteins from donor tissue that are allelicly different to recipient are processed by recipient APCs

Question 7

Explain SPUR

Answer 7

Serious
Persistent
Unusual/opportunistic
Recurrent

Infections in immune deficiency

Question 8

What is associated with antibody defects?

Answer 8

Bacterial infection

Question 9

What is associated with T cell defects?

Answer 9

Fungi, viruses and GvHD

Question 10

What causes GvHD?

Answer 10

Happens in bone marrow transplantation-caused by T cells in BM

Question 11

What infections are associated with phagocytic defects?

Answer 11

Abscesses

Question 12

What is associated with terminal complement defects?

Answer 12

Neisseria

Question 13

What is associated with classical complement defects?

Answer 13

Bacteria

Question 14

What is an example of an antibody deficiency?

Answer 14

Agammaglobulinaemia/ brutans syndrome. Due to a mutation in a tyrosine kinase essential for B cell formation

Question 15

What happens b-cells if yo lack tyrosine kinase?

Answer 15

B cells can’t be generated from immature B cells in bone marrow

Question 16

What happens if you have an IgA deficiency?

Answer 16

Susceptible to infections

Question 17

What causes hyper IgM?

Answer 17

Can’t undergo class switching. May lack cd40 expression of B cells that allows it to interact with t helper cells

Question 18

What causes secondary antibody deficiencies?

Answer 18

Lymphoproliferative disease- leukaemias. Malnutrition

Question 19

What causes transient hypogammaglobinaemia in infancy?

Answer 19

Transplacental transfer takes place in last 3 months of pregnancy- if baby is immature may lack IgG

Question 20

What is the effect of di George syndrome/thymic hypoplasia?

Answer 20

Genetic defects that cause developmental defects of 3rd and 4th pharyngeal arches

Question 21

What is the effect of di George on the parathyroids?

Answer 21

Hypocalcaemia

Question 22

What is the effect of di George on the great vessels?

Answer 22

Congenital heart disease

Question 23

What is the effect of di George on the thymus?

Answer 23

T cell deficiency - fungal, viral infections, graft vs host

Question 24

What is the HIV target?

Answer 24

Infects helper T cells by binding to cd4 molecules

Question 25

What is seroconversion illness?

Answer 25

10-15% of patients infected with hiv. Body produces antibodies to virus.

Question 26

How is AIDS defined

Answer 26

By Th appearance of opportunistic infections

Question 27

How many HIV viruses are there?

Answer 27

Two. Hiv-1 and his-2

Question 28

AIDS is defined as a cd4 t Cell count of what?

Answer 28

Less than 200 microlitres

Question 29

How does HIV escape detection?

Answer 29

Original detected by cytotoxic T cells but virus creates subtypes as it replicates so it escapes detection- as t helper cells are killed off- no adaptive immunity

Question 30

What does HART stand for?

Answer 30

Highly active retroviral therapys

Question 31

What is multiple kaposi's sarcoma?

Answer 31

Cancer caused by herpes virus found in AIDS

Question 32

What is severe combined immune deficiency? (SCID)

Answer 32

Inherited stem cell deficiency- lack of function in t and B cells

Question 33

What is kostnanns syndrome?

Answer 33

Primary disorder of neutrophils. Reduced production

Question 34

What is leucocyte adhesion deficiency?

Answer 34

Defect in production of integrins required for neutrophils to stick to blood vessels to get to infected tissues

Question 35

Chronic granulomatous disease?

Answer 35

Primary disorder of neutrophils- can't kill microbes- can't generate reactive oxygen species required for killing bacteria)

Question 36

What do defects in c1q, c2 or c4 cause?

Answer 36

Immune complex disease. Complement complexes can't be cleared from spleen or liver - damages tissue eg kidney

Question 37

What are iatrogenic causes of secondary immune deficiency?

Answer 37

Immunosuppressive treatment. Removal of lymphoid tissue