INNATE INMUNE SYSTEM Flashcards
What are the 4 main functions of INMUNE SYSTEM?
- DEFENSE AGAINST INFECTION
- DEFENSE AGAINST NEOPLASIA
- PRODUCTION INFLAMMATION (TISSUE DAMAGE)
- RECOGNITION AND RESPONSE TO FOREIGN TISSUES.
What function of inmune system is compromised in Autoinmune disease?
Production of inflammation
What are the 2 components of innate inmune system?
1.Bloodborne Component
2. Physical barrier Component
Bloodborne innate system’s elements
Complement System
PMN
NK Cells
Monocytes
APC’s
Physical barrier’s elements
Skin, mucosal membranes, stomach acid, saliva
Characteristics of the Innate Inmune System
- NONSPECIFIC
- RAPID EFFECT
- COMPOSED OF BLOODBORNE + PHYSICAL BARRIER
Functions of the Innate inmune system (6)
- Recruitment of inmune cells (Inflammation)
- Activate complement cascade
- Kill virus infected cells (NK CELLS)
- Activate Adaptive Inmune Syst (APCs)
- Assist in phagocytosis of foreign material
- Physical/Chemical barrier against agents
Which element of the Innate IS is in charge of killing VIRUS-INFECTED CELLS
NK Cells
Which element of the Innate IS activates the Adaptive IS
Dendritic cells (APCs)
Which element assists in phagocytosis of foreign material
Complement cascade (C3b)
Via which element APCs detect microbes or tissue damage?
PATTERN RECOGNITION RECEPTORS
- Toll-Like Receptors
Once a Pattern Recognition Receptor is detected, it produces secretion of
CYTOKINES:
- IL-1
- TNF-alfa
Secretion of IL-1 and TNF-alfa promotes
Leukocyte migration
Which cells of the Innate IS can detect microbes and tissue damage?
- APCs
- Marophages
- Neutrophiles
How does NK Cells recruitment is done?
Plasmacytoid (Specialized APCs) produce TYPE I IFN (alpha-beta)
Type I Interferon promotes
- Anti viral state
- Enhancing of NK Cells
How the Innate IS activates the Adaptive IS
2 vias:
1. Cytokine secretion (IL-1, IL-2, IL-6)
2. APCs presents to T-Cells via MHC II
Once they find an antigen, APCs will go to ____________
Lymph nodes for T-Cell activation
APCs promotes T-Cell activation via __________
MHC II
Which is the first cell in respond in bacterial/fungal infection?
NEUTROPHILES
Which is the most abundant leukocyte?
NEUTROPHILES
Which is the primary function of the neutrophil?
Phagocytosis
Neutrophiles contain receptors for
Complement System
Antibodies
Monocytes turn into ___________ when migrate to tissue
Macrophages
Macrophages before migration to tissue are located in __________ and are known as ____________
Blood / Monocytes
Function of the macrophages
- Regulation of inflammation (Cytokines)
- Phagocytosis
3.Antigen presentation to T-Cells - Tissue repair
How do Macrophage activation occur?
- Component of microbes bind to PRR
- Via Cytokine IFN-Gamma
Types of PRR
- Toll-like receptor
- NOD-like receptor
Toll-like receptors bind to
Peptidoglycan
Flagellin
Viral RNA
NOD-like receptors bind to
Biomolecules associated with cellular damage
What is a Dendritic cell?
- The PRIMARY APC for T-Cell (MHC II)
- Link between Adaptive and Innate IS
Mast cells are Leukocytes characterized for
- Having large cytoplasmic granules
Mast cell degranulation occurs when ____________ and promotes ______________
They bind to microbial products /
Secretion of Vasoactive substances and Proteolytic enzymes
What kind of vasoactive substances do Mast Cells produce?
HISTAMINE
Sustance P
Which leukocyte is in charge of combatting parasytic infections?
Basophils and Eosinophils
NK Cells are essentially Lymphocytes without __________
T-Cell receptor
Besides kill virus-infected cells, NK also kills ____________
Tumor cells
Explain the cycle of activation between NK and Macrophages
- NK cells promote macrophage activation by secreting INF-Gamma
- Macrophages promote NK Cells activation by IL-15, IL-12 and Type I IFN.
Which Cytokines activate NK Cells
IL-12, IL-15 and Type I IFN
NK Cells can bind to Antibodies via
CD16
How do NK Cells kill virus-infected cells
1) Secretion of Granzime/Perforins for Apoptosis
2) Via Antibody dependant cellular toxicity (Bind to AB via CD16)
Activation of Complement System starts with
C3 is separated into C3a and C3b
C3b is in charge of
Profuction of Opsin by C3b = Enhancing of Phagocytosis
C3a is in charge of
Chemotaxis ( and activation of C5a) = Inflammation
Complement’s C5a function
Activation of MAC Complex = Cell Lysis
Which components of Complement System form the MAC Complex
C6-C9
Pathways of Complement System Activation
1) Alternative pathway
2) Classical pathway
3) Lectin pathway
Which Complement activation pathway is antibody-mediated?
Classical pathway
Which complement activation pathway is associated to innate IS?
Alternative pathway
