Lymphoid system Flashcards Preview

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Flashcards in Lymphoid system Deck (30):
1

What are the three main classes of lymphocytes?

B cells
T cells
NK cells

2

Where do the arterial and venous vessels serving the node enter and leave lymph nodes?

Hilum

3

Where do lymph eventually enter the venous system?

Junction of the R or L subclavian and jugular veins

4

Which lymphocytes are involved in Humoral immunity?

B lymphocytes

5

Which lymphocytes are involved in cell mediated immunity?

T lymphocytes

6

How are resting B lymphocyes arranged in lymph nodes?

Primary follicles

7

Where in the lymph node do activated B cells go?

Germinal centres

8

If B cells are particularly prominant in a lymph node what kind of conditions are you thinking about?

Autoimmune
Infections (bacterial)

9

If T cells are particularly prominant in a lymph node what kind of conditions are you thinking about?

Viral infection
Drugs such as phenytoin

10

What does the red pulp of the spleen contain?

Sinusoids and cords

11

What does the spleen do, from an immunological perspective?

Acts as a filter for blood - detects retains and eliminates unwanted, foreign or damaged material and facilitates immune response to blood borne antigens.

12

What is the triad of symptoms seen in hypersplenism?

1. Splenomegaly
2. Fall in one or more of the cellular components of blood
3. Correction of cytopenias

13

What three disease can cause hyposplenism?

Coeliac disease
Sarcoidosis
Sickle cell disease

14

What are the two main functions of the lymphatic system?

Return lymph to the circulation
Filter lymph before return to circulation

15

In what conditions in the lymph node response primarily due to B cells?

Autoimmune conditions
Infections

16

In what conditions in the lymph node response primarily due to phagocytes?

Draining of a tumour site

17

In what conditions in the lymph node response primarily due to T cells?

Viral infections
Drugs such as phenytoin

18

What artery supplies the spleen and what is this artery a branch of?

Splenic artery - branch of the coeliac trunjk

19

Describe the venous drainage of the spleen?

Drained by the splenic vein which joins with the superior mesenteric vein to form the portal vein.

20

Describe the immunological function of the spleen

Detects retains and eliminates unwanted, foreign or damaged material
Facilitates the immune response to blood borne antigens

21

What does the red pulp of the spleen contain?

Sinusoids which are filled with blood
Splenic cords
Marginal zone next to the white pulp

22

What do the splenic cords contains?

Macrophages
Fibroblasts
Cells in transit

23

What is the main function of the red pulp of the spleen?

Mechanical filtration of red blood cells

24

What is the main function of the white pulp of the spleen?

Activation of the immune response through humeral and cell mediated pathways

25

What does the white pulp of the spleen contain?

Nodules called malpighian corpuscles composed of:
- Lymphoid follicles rich in B lymphocytes
- Periarteriolar lymphoid sheaths rich in T lymphocytes (CD4+ cells)

26

What is the triad of hypersplenism?

1. Splenomegaly
2. Fall in one or more of the cellular components of the blood.
3. Correction of cytopenias by splenectomy

27

In hyposplenism are the features mainly from reduced red pulp or white pulp function?

Red pulp

28

What might you see on a peripheral blood smear of someone with hyposplenism?

Howell Jolly bodies

29

What is a howell jolly body?

Basophilic nuclear remnants in circulating erythrocytes. Purple spot in the erythrocyte in peripheral blood smear.

30

What would you think of as a diagnosis if you saw howell jolly bodies on peripheral blood smear?

Reduced splenic funtion