Immune Organs Flashcards Preview

MCD- Immunology > Immune Organs > Flashcards

Flashcards in Immune Organs Deck (13):
1

Primary lymphoid organs

Bone marrow and thymus where lymphocytes are produced

2

Secondary lymphoid organs

Spleen, lymph node, mucosal associated lymphoid tissue
Where antigen meets lymphocytes

3

The thymus

Bi lobed
Medulla - not very stained
Cortex - highly stained
No change during infection
Older = fewer new T cells produced so they become less diverse

4

Bone marrow

Red = cells
Yellow = fat
Adults = more fat, fewer cells

5

Lymph nodes

Lymphatic fluid is filtered
T cells in the centre
B on the outside
More B cell production = germinal centres form

6

How do lymphocytes enter lymph node?

High endothelial venules
Lymphocyte rolling
Chemokine receptor on lymphocyte binds to chemokine on HEV
Integrity on lymphocyte has a higher affinity for receptor
Stops

7

Spleen

Filter antigens in blood
White pulp where lymphocytes are
Next to splenic artery = periarterial lymphatic sheath (T) then B region
Without spleen = more infected by encapsulated bacteria

8

Peyers patch

In gut
Germinal centre and follicles
M cell samples antigen and presents it to lymphocytes in the peyers patch

9

Cutaneous immune system

Dendritic cells of skin and mucosa
Lymphocytes
Keratinocytes = detect damage to skin
Macrophages

10

What does selectin do?

Allows weak binding of lymphocyte to HEV

11

Classify T cell receptors

All express CD3
Alpha beta TCR or beta gamma TCR

Of the alpha beta
2/3 express CD4 helper
1/3 express CD8 cytotoxic

Recognise process antigens

12

B lymphocyte markers

CD19 and CD20
Express MCG class II
Antigen presenting cell
Recognise intact antigens

13

Antigen presenting cells and their location

Dendritic - skin and mucosal
B - lymphoid tissue
Macrophages- lymphoid tissue