Overview Flashcards
Innate Immunity have cells that arise from what?
myeloid progenitor cells
What type of immune cells recognize general features of some pathogens such as repeating subunits that are common to many organisms?
innate immunity
General features that the innate immune system recognize are known as what?
PAMPS - (pathogen-associated molecular patterns)
PAMPS are recognized by what?
PRRs (pattern recognition receptors) that are found on a variety of immune cells
T/F Innate cells recognize signals from the acquired immune response that modulate their responses
true
How do innate cells help to initiate acquired immune cells?
innate cells (macs, dendritic cells) help by processing and presenting antigen to lymphocytes
What are the cells that mediate acquired immune responses?
lymphocytes
How are specific antigens recognized?
the recognition of specific sequences of amino acids, epitope or antigenic determinant
How is immunological memory provide a rapid response upon re-exposure to a pathogen?
upon encounter with specific epitope, lymphocytes produce protein factors (cytokines) to “help” other lymphocytes as well as regulate the activities of innate cells
Where is the site where all elements of the blood are derived from one type of progenitor cell? What is this specific cell called?
Bone marrow
pluripotent hematopoietic stem cell (hSC)
hSC give rise to 2 progenitors that give rise to the rest of the immune system. What are they?
- myeloid progenitor
- common lymphoid progenitor
The myeloid progenitor is the precursor for what? What type of immunity do these cells provide?
- granulocytes
- macrophages
- dendritic cells
- mast cells
Innate immunity
What is the group of cells that make up most of the innate immune system which are polymorphonuclear cells? What are the types of these cells?
granulocytes
- neutrophils
- eosinophils
- basophils
What are phagocytic cells that help activate bacteriocidal mechanisms?
neutrophils
What ar cells that kill antibody-coated parasites?
eosinophils
What type of granulocyte has an unknown function but is very similar to eosinophils?
basophils
What cell stems fromthe myeloid progenitor that are scavenger cells that have receptors for a variety of structures that are common to infectious agents?
macrophages (macs)
What cells play an important role in initiation of acquired immune responses?
macrophages
The immature circulating form precursors of macs are what?
monocytes
What are cells that are the most potent stimulators of T cell responses?
What is an important characteristic of these?
dendritic cells
branched, dendritic morphology
What cells take up antigen at the sites of infection/inflammation? Where do they take the antigen after and to what?
dendritic cells take up antigen then return to 2ndary lymphoid tissue to present antignes to naive T cells
What cells stem from myeloid progenitors degranulate to release histamine? What type of hypersensitivity are they associated with?
mast cells
associated with type I hypersensitivity rxns
Describe how macrophages and dendritic cells help initiate the development of acquired immune responses
- take up protein antigens
- process antigen (cut it into pieces)
- present antigen to naive T cells
- initiation of acquired immune responses
What cells have IgE receptors on their surface so that their activity can be modulated by acquired immunity?
mast cells
What gives rise to T cells and B cells?
common lymphoid progenitor
What gives tise to the Natural killer cells?
common lymphoid progenitor
Of the cells that come from the common lymphoid progenitor, which express receptor molecules on their surface and which do not?
T cells and B cells express receptor molecules on their surface to allow them to specifically recognize forein antigens
Natural killer cells (NKs) do NOT express antigen specific cell surface receptors
T/F all cells of the immune system originate from the bone marrow
Where do cells of the immune system circulate?
blood and lymphatic system
Describe where lymphocytes are generated and where they mature
- generated in bone marrow from common lymphoid progenitor cells
- migrate to lymphoid organs where they differentiate or mature
What are organized tissues where lymphocytes interact with non-lymphoid cells (antigen presenting cells or APC)?
lymphoid organs
What are the 2 main actions that occur in the lymphoid organs?
- development
- initiate of adaptive immune respones
Where do lymphocytes develop and mature?
central lymphoid organs or primary lymphoid organs
Where do T cells originate? B cells?
Where do T cells mature? B cells?
Both originate in bone marrow
T cells mature in thymus; B cells mature in bone marrow
Where are adaptive immune responses initiated?
peripheral lymphoid organs (2nd lymphoid organs)
What are the 2 actions that take place in the peripheral lymphoid organs?
- designed to trap antigens
- facilitate presentation of these antigens to lymphocytes
What is the peripheral lymphoid organ that colelcts antigen from the blood? What is its main function?
spleen
dispose of dead RBCs
The spleen is made up of red pulp and white pulp. Describe them
red pulp=> site of RBC disposal
white pulp=> lymphocytes surround arterioles entering the spleen
- white pulp divided into periarteriolar lymphoid sheath (PALS) which contain primarily T cells with flanking B cell corona
What are highly organized lymphoid tissues that collect antigen from lymphatics? Describe the process to reach this peripheral lymphoid organ
lymph nodes
- lymphatic vessels collect extracellular fluid from tissues
- return it to bloodstream
- lymph is continuously produced by filtration of blood
Describe the location of B cells and T cells w/in lymph nodes
B cells localized in follicles
- T cells distributed more diffusely in surrounding paracortical areas called T cell zones
Where are B cells undergoing intense proliferation? What occurs before this proliferation begins though?
Germinal centers
only following antigenic stimulation with T cell help
What tissues are associated with GALT (gut associated lymph tissue)? What is the function of these tissues?
tonsils, adenoids, appendix, Peyer’s patches
function is to capture antigen from eipthelial surfaces of GI tract
What tissue are the most important GALT tissues and have specialized cells called M cells? What is the fxn of M cells?
Peyer’s patches
M cells collect antigens along intestinal mucosa