Ch. 1: Intro to Immune System

Question 1

Characteristic of Humeral Immunity

Answer 1

• B-cell/antibody mediated
• acts on EXTRA-cellular antigens on cell surfaces and in blood
• Recognize proteins in conformational folding

Question 2

Characteristics of Cell- mediated immunity

Answer 2

• Adaptive
• Intracellular microbes - have been chopped up and presented by MHC
• T-cells

Question 3

Properties of Adaptive Immune response

Answer 3

• specificity
• Diversity of lymphocytes antibodies and TCR
• Memory - larger fast secondary response
• clonal expansion
• specialization - fight each microbe in a way that specific to it - unlike innate that treats all the same
• contraction/homeostasis
• non-reactivity to self

Question 4

CD4+ T-cells

Answer 4

• aka Helper or Effector T-cells
• regulate T-cell response
• produce cytokines
• activate B-cells
• Activate macrophages
• Th1 and Th2 and Th17 responses

Question 5

Follicular dendritic cells

Answer 5

• located in germinal centers of lymph nodes

- presents antigens only to B-CELLS

Question 6

Primary Lymph Organs

Answer 6

• Bone Marrow
• Thymus
• where B & T cells mature

Question 7

Secondary Lymph tissue (Peripheral)

Answer 7

• Where adaptive immune responses are initiated
• Lymph Nodes
• Spleen
• Mucosal and cutaneous - pharyngel tonsils, Peyer’s patches in gut

Question 8

Location of B/T cells in lymph node and spleen

Answer 8

Lymph Node:
- B-cells - follicles around the cortex (have germinal centers)
- T-cells - besides follicles - Paracortex
Spleen
- B-cells - Follicles
-T-cells - Peri-arteriolar lymphoid sheaths

Question 9

T-cell migration/re-circulation

Answer 9

• Naive T-cells exit Thymus into blood
• Reach HIGH ENDOTHELIAL VENULES (HEV, post cap venules)
• T-cells express L-selectin which binds to special carbs on HEV
• They enter the paracortex and then can be activated/proliferate if contact antigen
• if not just continue out and re-circulate back and forth btw blood and lymph (go into lymph drainage from node, then back into blood at thoracic duct)

Question 10

T-cell antigens

Answer 10

tend to be proteins that are chopped into peptides by APC (most T-cells don’t recognize lipids or carbs)

Question 11

Heavy Chain class isotype switching

Answer 11

production of different antibodies with the same specificity

• Fc region of heavy chain varies - light chain stays the same
• antibody for same antigen just made at different times and has different functions

Question 12

Affinity Maturation

Answer 12

• Helper T-cells stimulate the productions of antibodies with higher and higher affinity for the antigen
  
  • when a B-cell proliferates there can be mutations, and those with greatest affinity survive

Question 13

Antibody function

Answer 13

• bind to antigen so that it can’t infect cells
• opsonize microbe for phagocytosis
• activate the complement system