4. Pemrosesan, Presentasi Antigen & Aktivasi Sel

D I A N E U R I K E S E P T Y A N I N G T R I A S

F A C U L T Y O F M E D I C I N E

U N I V E R S I T A S G A D J A H M A D A

Antigen Processing, Antigen Presentation, & Dendritic cell Activation

[email protected]

Antigen uptake by dendritic cells

Dendritic cells take up pathogens.

Antigen processing

The dendritic cells process the pathogens. So that the pathogens

can be recognized by T cells.

Antigen processing.

T cells can only recognize a peptide presented on the surface of antigen-

presenting cell through MHC molecule.

Dendritic cell migration

The dendritic cells migrates to the draining lymph node.

DC migration

Antigen presentation to T lymphocytes

The dendritic cell presents an antigen to naïve specific T lymphocyte.

Intracellular Pathogens Processing & Presentation

Intracellular pathogens

• Virus

• Intracellular bacteria

Presented to T cell by MHC class I

Intracellular antigen processing

Extracellular Pathogens Processing & Presentation

Extracellular antigen processing

Extracellular antigen processing

Review

MHC molecules expression on human cells

All nucleated cells express MHC class I .

Only certain cells express MHC class II .

MHC molecules expression on human cells

Dendritic cells, B cells, and macrophages express both MHC

class I and class II.

But only dendritic cells is known as professional antigen presenting cell.

Those cells are antigen-presenting cells.

Dendritic cells as proffesionalantigen-presenting cells

Express co-stimulatory molecules.

Migrate to the lymphoid organs to present the antigen to T cell.

Distributed throughout the body and have processes which help in antigen uptake.

Dendritic Cell Activation

Dendritic Cells Maturation

Ag processing

Dendritic cells begin a maturation process as they migrate via the

lymphatics to the draining lymph node

DC maturation

Dendritic Cell Maturation

Changes occur in the surface marker of dendritic cell by which change

the nature of dendritic cell.

Play role in DC migration to T cell zone of lymphoid organ.

Co-stimulatory molecule which play role in T cell activation.

Able to phagocyte pathogens.

Mature vs Immature Dendritic Cells

Mature dendritic cell migrates to T cell zone of the secondary

lymphoid organ

DC maturation

Mature dendritic cell activates antigen-specific T lymphocyte.