Immune System and Lymph Nodes

Question 1

2 Types of defenses?

Answer 1

Innate - surface barriers, internal defenses
Adaptive - humoral (B-cell) and cellular (T-cell) immunity

Question 2

5 Structures of Lymphatic System?

Answer 2

tonsils, thymus, spleen, lymph nodes
MALT (mucosa associated lymph tissue)
– BALT (bronchus…)
– GALT (gut…)

Question 3

Primary vs secondary lymphoid organs?

Answer 3

Primary
- Thymus (T-cells) and Bone Marrow (B-cells)
Secondary
- diffuse lymphatic tissue, lymph nodules, spleen

Question 4

3 types of Lymphocytes?

Answer 4

T cells (helper, cytotoxic, suppressor)
B cells
Natural Killer Cells

Question 5

Supporting cells of immune system?

Answer 5

reticular cells – make reticular fiber
macrophages – from monocytes
follicular dendritic cells (not antigen presenting)
epithelioreticular cells – reticular cells of thymus
langerhans’ cells (antigen presenting)

Question 6

T Cells function?

Answer 6

macrophage present antigen to helper T cell
– cytokine (more helper T + expansion of cytotoxic T)
cytotoxic T cells
- memory cells
- killer cells (release granzymes and perforins)

Question 7

B cells function?

Answer 7

antibody contacts B cell –> presents to helper T cell
– cytokine (expansion of B cells)
B cells
- plasma cells (immunoglobulin response)
- memory B cells

Question 8

Natural Killer Cells function?

Answer 8

interferon activates NK
– release granzymes and perforin = apoptosis
Fc receptors on NK cells bind to IgG to recognize tumor antigen

Question 9

Diffuse lymphatic tissue?

Answer 9

• no capsule
• lymphatic cells with goblet cells
• mucous membranes

Question 10

Lymphatic nodules layers?

Answer 10

NO CAPSULE
Germinal center (large lymphocytes)
- proliferating B cells
Mantle Zone
- inactive B cells

Question 11

Follicular Dendritic Cells?

Answer 11

support B cells
- hold antigen in place

Question 12

Lymph Node Structure?
- edge?
- layers?
- entrance and exit?

Answer 12

Capsule (dIRCT)
Sub-capsular sinus (reticular cells/fibers)
Trabeculum (project into lymph)

Cortex (lymphatic nodules here)
Medulla (medullary cord + sinus)

Afferent and Efferent lymphatic vessel
Hilum (blood vessels supply)

Question 13

high endothelial venules composition and function?

Answer 13

cuboidal - columnar endothelial cells
- blood supply for lymphocytes to enter lymph node

Question 14

How do lymphocytes enter lymph node?

Answer 14

1) High endothelial venule (blood supply)
2) Afferent lymphatic vessels (lymph supply)