The Cells of the Adaptive Immune System

Question 1

Recap: cells of the innate immune system

Answer 1

Eo, Ne, basophil, monocyte 
Dendritic cell
NK cell
Mast cell
Macrophage 
Complement factors

Question 2

Recap: cells of the adaptive immune system

Answer 2

T-Cells: CD8+ and CD4+
Cytokines
Antibodies
B-cells

Question 3

Common pathway cells

Answer 3

gamma delta T-cell

NK T-Cell (important bridge btw the 2)

Question 4

T-Cells

Answer 4

Progenitor are formed in the BM
Immature T-cells migrate to the thymus
Receptors: alphabeta and gammadelta
gammadelta- migrate to mucosa without maturing in the thymus
alphabeta mature in thymus (many die)
Atg. recognition: there is MHC restriction
Cell-line marker: CD3

Question 5

Types of T-Cells

Answer 5

1. Receptor based
   - Conventional alphabeta
   - Non-conventional alphabeta NK (non-variable chains)
   - gammadelta
2. Function based
   - Effectors (cytotoxic, helper, regulatory)
   - Memory T-cells

Question 6

Cytotoxic T-Cells (Tc)

Answer 6

Cell surface markers: CD3+ and CD8+
Recognition of endogenous Atg presented through MHCI
Protection against viral infections, tumors and IC pathogens (Chlamydia, Lawsonia, Mycobact)

Question 7

T-Helper Cells (Th)

Answer 7

Cell surface markers: CD3+ and CD4+
Recognition of exogenous Atg presented through MHCII
Subtypes: Th1 and Th2
Produce CK!! and these produce cytokines- immune response
Th17- enhances inflamm
Treg: decrease the Atg specific immune response

Question 8

Gamma delta T-Cell

Answer 8

The TCR contains gamma and delta chains
Migrate to the periphery before or after reaching the thymus
In blood in small amounts
Presence on mucus membranes as intaepithelic lymphocytes (IEL)
Atg. recognition without MHC!!!!
Reaction mainly to lipids- tolerance

Question 9

Recap: B-Cells

Answer 9

Progenitor and immature in the bone marrow and bursa fabricii in birds
Native Atg recognition (conformation epitop)
No MHC restriction!!
The further differentiation (secondary maturation) is stimulated by antigens, and the products are plasma cells or memory cells, and this occurs in folliculi.
Clonal B-Cell receptor
Cell-line marker: CD19+

Question 10

Marginal Zone B-Cells (MZB)

Answer 10

Marginal zone is btw the red pulp and the follicles
Are sessile macrophages and special B-Cells
Express high amounts of IgM and CD21, but negligible amounts of CD23
Important in detecting bacterial carbs
Can transform into IgG or IgA
Provides rapid systemic immune response