Immunology Flashcards
What is the difference between active and passive immunity?
Active immunity - is encountering the infection previously
Passive immunity - is through the acquisition of antibodies
What is innate immunity?
The first line of defense which aims to protect against any kind of pathogen
A non-specific mechanism that is fairly fast acting
what are the 4 major barriers with innate immunity??
1) Structural/phsyical barriers (eg skin, mucous membranes)
2) chemical barriers (eg temperature,low pH, chemical mediators
3) inflammatory barriers
(inflammation)
4)phagocytic barriers (eg. Neutrophils,monocytes,macrophages)
What are cytokines?
Small proteins that are the signaling chemicals of the immune systems
Mediate inflammation
Attract and activate other immune cells
What is adaptive immunity?
Where specific molecules (antigens) are recognized and eliminated
What are the 4 characteristic attributes of adaptive immunity?
1) antigenic specificity
2) diversity
3) immunological memory
4) self-recognition
What do antigen presenting cells do?
They engulf the antigen, then process and present it to other effector cells (eg. T cells)
What do B cells do?
They encounter the antigen and then divide (into memory B cells or plasma cells - antibodies)
Describe the 7 step process that occurs in T cells to kill a cell?
1) macrophage in tissues picks up viral particle released from an infected cell
2) antigen processed then presented outside cell
3) macrophage releases signaling molecules
4) attracted T helper cells recognizes antigen
5) activated T helper releases cytokines
6) cytotoxic T cells activated then recognize infected body cells
7) infected body cell killed
What are the two types of cytotoxic cells?
Cytotoxic T cells - adaptive immunity
Natural killer cells - innate immunity
Both cells contain granules filled with potent chemicals which Lyse the cells and punch holes in the membrane allowing protein digesting cells to enter
How can passive and active immunity be acquired?
Active immunity can be acquired via vaccination/memory cells
Passive immunity - we inherit some immunity from motherzoid
How long is the lag time in response to an antigen?
Approximately 5 days
