Innate Immunity - Robison Flashcards
What are primary lymphoid organs?
Bone marrow and thymus
What are the secondary lymphoid organs?
Anywhere else the lymphocytes interact
Ex. lymph nodes, MALT, spleen, tonsils
What is the first immune cell to the scene?
Neutrophils
What are the types of Dendritic cells?
Langerhans cells - keratinized epidermis dendritic cells
Dermal Dendritic Cells- in the dermal layer
M cells- Dendritic cells in the small intestine that transport antigens to the mucosal layer
Plasmacytoid Dendritic Cells- circulate in blood and produce type 1 interferon when encountering viruses
What is unique about innate immunity?
Non-specific
Fast
No memory
Similar in the same species
What is unique about adaptive immunity?
Specific
Slow
Memory
Different from person to person
Why is skin an effective antimicrobial barrier?
Non-specific defense
First line of defense
Physical barrier with very active antimicrobial peptide
Name some antimicrobial peptides and their functions
Alpha Defensins: on neutrophils and poke holes in the microbial membrane
Beta Defensins: on nearly every cells; chemotactic, and induces histamine release and also pokes holes in the microbial membrane
Cathelicidins: in lysozymes
What are Paneth cells, where are they, and what do they contain?
Paneth cells are in the small intestine
They contain two types of alpha defensins
Kills Giardia and E. Coli
How do defensins work?
They bind acidic phospholipids in the membranes of microbes and generate pores
What are the three pathways of complement activation?
Lectin, Classical, and Alternative
How does the Lectin pathway get activated?
MBL and Ficolin both contain MASP 1 and 2 and bind to sugars on the microbe
How does the Classical pathway get activated?
IgG and IgM can activate C1 to start cleaving
How does the Alternative pathway get activated?
Uses C3b with Factor B to create a C3 convertase type
What inhibits the complement pathway?
Factor H and I
