Trigger 5: T1D and insulitis

Question 1

Insulitis is the

Answer 1

manifestation of the autoimmune attack against beta cells

Question 2

Insulitis is a

Answer 2

hallmark of T1D

Question 3

insulitis is characterised by

Answer 3

the presence of immune and inflammatory cells within the pancreatic islets

Question 4

definition of insulitis

Answer 4

the presence of a predominately lymphocytic (B and T cells) infiltration of the islets of langerhans.

• consists of at least 15 CD45+ cells
• present in a minimum of three islets

Question 5

while both T and B cells are reported in insulitis lesions, which cells are the predominant population

Answer 5

cytotoxic CD8 T cells

Question 6

CD8 T cells are though to target B cells which

Answer 6

express elevated levels of HLA class I molecule e.g. MHC 1

Question 7

hyper expression of MHC I (HLA class I molecule)

Answer 7

may be associated with viral infections implicated in the development of t1DM

Question 8

when a CD8 T cells recognises a B cell over expressing MHC 1receptors

Answer 8

cytotoxic killing via apoptosis

Question 9

hyper expression of HLA molecules is another

Answer 9

key feature in the pathology of T1D- represents chronic inflammatory state

Question 10

immune cells infiltrate islets in a

Answer 10

non-uniform fashion

Question 11

when lymphocytes infiltrate

Answer 11

decrease in Beta cells mass and lesions in pancreas

Question 12

which immune cells ae present wishing insulitis infilitration

Answer 12

• CD8 (which do killing)
• CD4 (in lesser amounts)
• CD20 B cells
• CD68+ macrohages

Question 13

what is a marker stain for all lymphoctes

Answer 13

CD45

Question 14

CD68 is a

Answer 14

glycoprotein found on the surface of macrophages

Question 15

CD20 is a

Answer 15

glycoprotein found on the surface of B cells

Question 16

CD4 is a

Answer 16

glycoprotein found on the surface of T helper cells

Question 17

CD8 is a

Answer 17

glycoprotein found on the surface of cytoxic T cells

Question 18

CD45

Answer 18

a marker for all lymphocytes

Question 19

HLA class 1 molecules is a

Answer 19

genome complex which encodes MHC I

Question 20

HLA class 2 molecules is a

Answer 20

genome complex which encodes MHC II

Question 21

immunostains targets

Answer 21

CD glycoproteins e.g. CD8/ CD4

Question 22

which types of cells are present in the highest concentration in T1D

Answer 22

CD8 T cells

Question 23

which cells are present the lowest conc in T1D

Answer 23

CD4 t cells

Question 24

as insulin content decreases

Answer 24

mean number of immune cells increases and then at a set point decreases to 0

Question 25

once insulin is gone

Answer 25

immune cells go back to where they came from 9therefore present in patients with newly diagnosed diabetes)

Question 26

both …. are involved in b cell destruction

Answer 26

by themselves- not strong enough

Question 27

insulin-speciifc autoantibodies (produced by bc els)

Answer 27

are present in children with T1D before the age of 5

Question 28

islet autoantibodies are

Answer 28

a differential diagnosis marker for T1D

Question 29

IAAs arise from

Answer 29

auto reactive B cells and CD4 T cell iteraction

Question 30

CD4 T cells and other immune cells

Answer 30

provide “help” to B cells and stimulate antibody production, as well as promote responses by effector CD8 T cells, and stimulate islet-resident macrophages.

Question 31

auto reactive CD4 T cells

Answer 31

• represent an active area of research and clinical interest for therapies. Developing antigen-specific tolerance-promoting methods to inhibit autoreactive CD4 T cells is an idea

Question 32

CD45

Answer 32

CD45 (lymphocyte common antigen) is a receptor-linked protein tyrosine phosphatase that is expressed on all leucocytes