cells and organs of the immune system Flashcards
(46 cards)
what is immune system
are cells and tissues in our body that recognize and attach foreign substances/pathogens in our body
how are we infected
- when pathogen bridge our first line of defence (are barriers which our body has build against the outside. example: skin, nose or epithelial cells lining our gut)
so, body use both epithelial and mucosal surfaces lining all contact area from outside to protect us.
what are mucosal or mucosal membrane
are membrane that line body cavity and surfaces of the internal organs.
they are consist of one or more epithelial cells on the surface.
mucosal membrane in our body they can secrete mucus for example in our nose to keep us health
what happens at the site of entry
- first microorganism have to get close to us
- phagocyte (can eat up the pathogens) and local immune response will become active and try to hear the wound, preventing us from infection.
- so if they can not hear/ take care of infection, local immune response will induce second phase called inflammantion
- in inflammation they will be macrophage recruited and activated and we dendritic cells that move to close lymphonode and initiate adaptive immunity.
-adaptive immunity have ability to target structure that are specific to the pathogen that is infecting us - adaptive immunity will protect us from re-infection bt creating memory immunity. it is accomplished by specific antibody to the pathogen
- specific T cells can make macrophage more efficient
- cytotoxic T cells can kill and affect cells where virus is duplicated.
what is inflammation
means they are more cells and immune molecule recruited to the site of infection.
ex: cytokine ,chemokines, complements, NK cells, phagocytes
what is cytokines and chemokines
cytokines are proteins made up of cells that affect behaviour of other cells. often immune cells
chemokines are proteins that stimulate migration and activation of other cells. they guide cells to different place in our body
what do we call cytokines made of lymphocytes
are called interleukines
what are the cells of immune system
we main focus on white blood cells/ leukocytes
they are neutrophils, eosinophil, basophils, lymphocytes and monocytes, T and B cells
where does all immune cells arise from
bone marrow or hematopoietic stem cells
what is red blood cells and platelets
red blood cell they transport oxygen
platelets they help to close up wound/ clotting
what are lymphoid progenetor
B and T cells (has antigen presenting receptors), NK cells, dendritic cells and ILC
what are cells in granulocytes
neutrophils, eosinophils, monocytes, basophil and lymphocytes
what is monocyte
they circulate in the blood and migrate into tissues and then they differentiate and become macrophages.
what is macrophage
-macrophage in tissues they are long lived , they engolf and kill pathogens
- they induce inflammation
- they secrete signal in proteins that activate other immune cells to form immune response
what is mast cells
- they found in tissues while other granulocytes are found in blood
- role in allergy responses
-they have granule structure which secrete the activation
where does cells in lymph node found
in blood and tissues
when does lymph node cells become effector cells
example: when T and B cells encounter antigen they differentiate into effector cells.
what are innate and adaptive immune response
- innate immune system is our first line of defence. and is based on pattern recognition receptor ( they are same always) that can detect common features of pathogens. so when it fails then
- adaptive immune system kick in. here we have antigen binding receptor (they can change and become better) involve and have high variability
what are cells that belongs to innate immune system
-NK cells
-granulocytes
-dendritic cells
- ILC
what are cells that belongs to adaptive immune system
B and T cells
what are task of different cells in innate immune system upon activation
- macrophage (present antigen to T cells) and neutrophils: responsible for phagocytosis, induce inflammantion and activation of bactericidal mechanism (kill bacteria).
- dendritic cells: antigen uptake in peripheral cites and presenting antigen in lymph nodes. they also link two systems. they activate adaptive immune response.
- eosinophil: kill antibody-coated parasite
-basophils; play role in allergy response
-mast cells: they release granules that contain histamine and other active agent. they play role in allergy
-NK cells: release lytic granules that kill virus-infected cells.
what are task of different cells in adaptive immune system upon activation
-dendritic cells: form a bridge btn innate and adaptive immune system. recognize pathogen receptor and they can be activated and stimulated early in infection. they ingest pathogen. they associate with antigen surface in the way they can be recognized by T cells. and they will find T cells that fit on their surfaces then they deliver 3 different signals
- T cells: need 3 signals to be activated. they stimulate B cells. then they differentiate and become plasma cells that can produce antibodies that help to fight the infection
-B. cells : need 2 signals to be activated to make antibodies.
how many signal do T and B cells need to be activated
T cells need 3 signals
B cells need 2 signals
what can activated T cells do
- they can activate B cells
- they can differentiate and become plasma cells that help to produce many antibodies.