Lecture 1: Overview of Immune Responses Flashcards
Cellular innate components
Phagocytes (macrophages, neutrophils), dendritic cells, natural killer cells, innate lymphoid cells
Steps in functional response of phagocytes
Recruitment of cells to site of infection
Recognition and activation by microbes
Ingestion of microbes by phagocytosis
Destruction of ingested microbes
Function of cytokines
Regulate growth and differentiation of all immune cells
Activate the effector functions of lymphocytes/phagocytes
Reactivity to self for innate and/or adaptive immunity?
None
Humoral innate components
Complements, APPs, cytokines, chemokines
T or F: Innate immune system exists before infection
True
Cells communicate through
Direct cell-cell contact and through interactions involving cytokines and chemokines
Macrophage maturation stages
Monocytes enter the blood circulation and migrate into tissues, where they further mature into macrophages, especially during inflammation
Each cytokine acts via
Specific signaling receptor expressed on target cell
Phagocytes include
Neutrophils and macrophages
Macrophages produced where and stimulated by
Produced in bone marrow, stimulated by M-CSF
Adaptive immunity
Longer to develop
Highly specific
Shows memory
How does innate immune system respond after repeated exposures to Ag
Same way every time
Phagocytes
Ability to ingest and digest microbes (innate)
Dendritic cell function
Potent stimulators of T cells to induce adaptive immunity
Can divide to myeloid DCs and plasmacytoid DCs
Also include langerhans cells
Mast cell location/function
Common at sites in the body exposed to external environment (skin)
Close proximity to blood vessels
Can release mediators to modulate behavior of nearby cells
Neutrophils are produced where and production is stimulated by what
In the bone marrow, stimulated by granulocyte colony stimulating factor (G-CSF)
Response to intracellular infections
Cytotoxic T cells
NK T cells
Macrophages/phagocytes
Innate immune cells include
Phagocytes
Natural killer cells
Blood components
Specificity of innate immunity is for
Ags shared by groups of related microbes and molecules produced by damaged host cells
Neutrophil life span
Circulate in blood for few hours to few days
What is an antibody
Protein produced by immune system when it detects antigens
Activated phagocytes secrete
Cytokines or promote or regulate immune responses
Diversity of innate immunity
Limited- germline encoded