Innate immunity Flashcards
What is the innate immune system?
The first line of defense in the immune system that responds rapidly and non-specifically to infections
What are the key features of innate immunity?
It is rapid non-specific and does not have immunological memory
What are the physical barriers in innate immunity?
The skin mucosal surfaces and epithelial cells
What are the chemical barriers in innate immunity?
Lysozymes in tears and saliva and acidic gastric juices in the stomach
What is the role of neutrophils in innate immunity?
They are the first responders to infections performing phagocytosis and releasing reactive oxygen species and cytokines
What are Toll-Like Receptors TLRs?
Receptors on immune cells that recognize common pathogen-associated molecular patterns PAMPs
What is phagocytosis?
The process by which immune cells engulf and destroy pathogens
What are macrophages?
Immune cells that patrol tissues perform phagocytosis and signal other immune cells to respond to infections
What is the complement system?
A group of proteins in the blood that enhances the ability of antibodies and immune cells to clear pathogens
What are the three pathways of complement activation?
The classical pathway the alternative pathway and the lectin pathway
What is the role of the classical complement pathway?
It is triggered by antigen-antibody complexes and leads to the lysis of pathogens
What triggers the lectin complement pathway?
It is triggered by mannose-binding lectin binding to carbohydrates on pathogens
What is the membrane attack complex MAC?
A structure formed by complement proteins that creates pores in pathogens leading to their lysis
What are eosinophils?
Immune cells involved in defending against parasitic infections and contributing to allergic reactions
What are basophils?
Immune cells that release histamine and play a role in allergic responses
What is the role of mast cells?
They release histamine and other chemicals during allergic reactions and infections
What is chemotaxis?
The movement of immune cells towards the site of infection in response to chemical signals
What are natural killer NK cells?
Immune cells that can kill infected or cancerous cells without the need for prior activation
What is acute inflammation?
A rapid immune response to infection involving the recruitment of immune cells pathogen destruction and tissue repair
What is the role of cytokines in innate immunity?
They act as signaling molecules that regulate immune responses and recruit other immune cells to the site of infection
What are pathogen-associated molecular patterns PAMPs?
Molecular structures that are commonly found on pathogens and recognized by innate immune receptors
What are damage-associated molecular patterns DAMPs?
Molecules released by damaged or dying cells that trigger an immune response
How does the innate immune system activate the adaptive immune system?
Through antigen presentation by dendritic cells to T cells
