Acquired Immune System Flashcards
(22 cards)
Adaptive Immune system
system of host defenses against pathogens
-can recognize and remember specific pathogens
Types of lymphocytes
B-Cells
T-Cells
Two types of acquired immunity
1- Humoral or B cell immunity
2- Cell mediated or T cell immunity
T Cell development
bone–>thymus–>stored peripheral lymphoid tissues
B cell development
Bone—>stored in peripheral Lymphoid tissue
Functional cycle of the B cell
Made in bone marrow–> Recognize infection–> Produce antibodies–> become memory cells
Phases of typical infection and adaptive immune response
- Innate response (establish infection)
- Induction of adaptive response
- Adaptive immune response
- Immunological memory
* *with a second exposure to a pathogen, response occurs with increased potency and duration
Mechanism of antibody action
- Direct action (enhances phagocytosis)
- agglutination
- precipitation
- neutralization - Activation of the compliment system
Antibody neutralization
Blocks viral binding site, coats bacteria and/or opsonization
Antibody Agglutination
Clumping of particles/microbes
Antibody Precipitation
creating chains and size eventually leading to phagocytosis by macrophage
Functions of the compliment system
- opsonization
- lysis of pathogen
- agglutination/neutralization
- chemotaxis- attracts phagocytes
- Activation of mast cells/basophils
- increased inflammation
T cells recognize antigens when bound to?
MHC protein on antigen-presenting cells
- T cells cannot see antigens on their own, need antigen presented to them
Antigen presenting cells
- macrophages
- dendritic cells
- B cells
Function of MCH-1
Present intracellular antigens to cytotoxic T cells (CD8)
Function of MCH-2
Present extracellular antigens to helper T cells (CD4)
Function of the Cytotoxic T cell
- Kill infected host cells, cancer cells, transplanted tissue
- Releases Perforin which causes cell lysis by forming a pore in the cell membrane
Function of the helper T cell (Th)
- Activate macrophages
- Stimulate B cells to produce antibodies
- Induce formation of cytotoxic T cells
Function of Th1
Activate macrophages (cell-mediated immunity)
Function of Th2
Activate the B cells, eosinophils, mast cells (Humoral immunity)
Disfunction of the adaptive immune system
- inadequate immunity
- excess immunity
- misdirected immunity
Intraoperative allergic reactions
- 90% of rxn occur from IV drugs within 5 minutes
- Most common life threatening Sx= Circulatory collapse
- Sometimes the only manifestation is refractory hypotension
