lecture 3

Question 1

What recognize T cells?

Answer 1

• peptides on antigen-presenting cells (APC)

Question 2

What is MHC?

Answer 2

• cluster of highly polymorphic genes divided into MHC class I and class II gene loci

Question 3

What display MHC class I and II?

Answer 3

antigens (peptides) to T cells

Question 4

Human MHC is…

Answer 4

HLA human leukocyte antigen

Question 5

MHC I molecules are composed of

Answer 5

alpha chain and non-polymorphic ß2-microglobulin

Question 6

what is the function of MHC I molecules?

Answer 6

• presentation of cytoplasmic and intracellular antigens

Question 7

In which groups are MHC I molecules divided?

Answer 7

a,b,c

Question 8

MHC II molecules are composed of?

Answer 8

2 polymorphic protein chains

- 1 alpha chain and one ß chain

Question 9

name the function of MHC II molecules

Answer 9

presentation of endosomol extracellular antigens

Question 10

MHC II molecules are divided into

Answer 10

group d,q,b

Question 11

To which type of T cells display MHC I molecules peptides?

Answer 11

CD8+ T cells

Question 12

Which MHC molecules display peptides to CD4+ T cells?

Answer 12

MHC II molecules

Question 13

What is the major barrier in tissue transplantation?

Answer 13

MHC

Question 14

What happens usually after transplantation to genetically non-identical individuals?

Answer 14

graft rejection

Question 15

Name the types of transplantation

Answer 15

• syngeneic
• allogeneic
• xenogeneic

Question 16

What type of transplantation is mostly used in humans?

Answer 16

allogeneic

Question 17

graft rejection could be

Answer 17

hyperacute, acute and chronic

Question 18

What mediates graft rejection?

Answer 18

MHC-specific T and B lymphocytes

Question 19

What could be a treatment for graft rejection?

Answer 19

immunosupression

Question 20

graft v. host disease (CvHD) happens where?

Answer 20

in bone marrow transplantation

Question 21

what is the mechanism behind CvHD?

Answer 21

reactivity of grafted mature T cells to host antigens

Question 22

what is important for transplantation and autoimmune disease?

Answer 22

• HLA typing

Question 23

Which number is the most important in HLA typing?

Answer 23

• first number -> A02:01/40:01

Question 24

Which techniques are used during HLA typing?

Answer 24

• serological or molecular menas

Question 25

What is examined during serological typing?

Answer 25

proteins on cell membrane

Question 26

How is the serology investigated?

Answer 26

- terasaki plates - antibodies against specific HLA proteins → each well with blood of patient → activation of complement system → lymphocytes from blood will die - sometimes false positive reaction

Question 27

What is examined during molecular typing?

Answer 27

- genes encoding specific proteins are detected

Question 28

What is the investigation method for molecular typing?

Answer 28

PCR

Question 29

what shows a positive reaction in molecular typing?

Answer 29

seen as band in gel after electrophoresis -> primers for HLA alleles

Question 30

Which transplantation is possible without cross matching?

Answer 30

- liver | - heart also because cross matching takes too long -> immunosupression after wards

Question 31

what is cross-matching done for?

Answer 31

- antibodies

Question 32

how is chronic reaction managed?

Answer 32

by changing the immunosupression

Question 33

what happens during chronic rejection?

Answer 33

in the vessel wall → fibrosis → occlusion of vessel → necrosis and dieing of graft

Question 34

What is caused by hyperacute rejection due to presence of memory cells in the recipient?

Answer 34

- intervascular thrombosis

Question 35

when does acute rejection occur?

Answer 35

after a few weeks → immune system needs time to generate antibodies/ t lymphocytes → graft will die

Question 36

what is the mechanism behind immunosupressiojn?

Answer 36

- supress cytotoxic T cells | - > cyclosporin A

Question 37

incorrect blood transfusion could lead to?

Answer 37

hemolytic lysis