chapter 8 Flashcards
comensal organisms
live peacefully on our skin and in our mucosal layers. and do not normally cause disease. they just chill there
live, and let live
pathogens
organism that causes disease to its host
immunity
being resistant to the to a disease or infection
innate resistance
ready to go and able to express their maximum protective effectiveness every time they are called to defend the body.
adaptave immune response
This very potent response differs from the innate response in that it initially is very weak (ineffective), but becomes very specific and amplifies a coordinated response geared specifically to whatever foreign agent has triggered it.
antigen (Ag)
Any substance recognized by the immune system, either the innate or adaptive aspect, is called an antigen (Ag).
An immature cell that can develop into all types of blood cells, including white blood cells, red blood cells, and platelets.
derived in the bone marrow, can differentiate into either a common lymphoid progenitor or into a common myeloid progenitor
common lymphoid progenitor
common lymphoid progenitor which further specializes into cells considered innate as well as cells of the adaptive immune response
common myeloid progenitor
common myeloid progenitor that differentiates into the rest of the innate cells of the immune system, as well as red blood cells and platelets.
leukocytes
‘white blood cells’. specialized cells that exit the blood to reside in tissues
The common myeloid progenitor cell gives rise to…
the erythroblast that produces erythrocytes (red blood cells),
megakaryocytes that produce platelets, an unknown precursor that gives rise to mast cells
granulocytes (eosinophils, basophils, and neutrophils),
monocytes that give rise to dendritic cells (DCs) and macrophages
the common lymphoid progenitor cell gives rise to…
lymphoid cells, namely B cells, T cells, and innate lymphoid cells (ILC) including natural killer (NK) cells.
primary immune system organs/tissues
sites where hematopoietic stem cells differentiate into the cells of the adaptive immune system – B and T lymphocytes. B cells differentiate in the bone marrow, while T cells differentiate in the thymus. As we will cover in greater detail in Part II of this module, both B and T cells go through a series of selection steps as ‘training’ to become a mature participant in the immune system. These selection/training steps occur within their respective primary lymphoid tissue.
secondary immune system organs/tissues
All other organs and tissues involved in the adaptive immune response are considered secondary lymphoid tissues.
mucosal-associated lymphoid tissues MALT
gut associated lymphoid tissue GALT
skin associated lymphoid tissue SALT
are secondary lymphoid tissues located near barriers commonly breached by invading organisms. They are able to provide context-specific signals to the adaptive immune system to help generate the most appropriate response.
adaptive immune responses two seperate branches to its response
humoral (antibody-mediated) immunity
- ‘antiserum’
-spreads antibodies around when sick
cellular (cell-mediated) immunity
1. Cytotoxic T cells (CTLs) can directly attack target cells that are infected with intracellular pathogens
- T-helper cells help the CTLs
epitopes
regions or sites on an antigen that is recognized by antibodies or T cell receptors
monovalent for 1 epitope
multivalent = more stronger
Antibody affinity
is the measure of how stongly a given antibody binds to a single epitope
a higher affinity indicates a stonger binding
Antibody avidiry
relates to the overall ability of an antibody or antiserum to bind to the complete antigen (additive effect of all epitopes)
haptens
some antigens dont issue an immune response unless attatched to a carrier protein
this is what a hapten is
histocompatibilty complex (MHC)
what is it called in humans
the primary dirver of tissue incompatibility between donors.
in humands the it is called the Human Leukocyte antigen (HLA) complex
3 classes of histocomaptibility complex (MHC) proteins
class I MHC - in all types of nucleated cells
class II MHC - appear only on cells that can process antigens and present them to T lyphpcyes
class III MHC - not requires for self/non-self discrimination
hypersensetivity type 1
AllergE (igE)
antibodies came in contact with (peanut) during B-cell phase. On re-contact the antigen (peanut) or similar antigen, causes basophil/mast cells to release histamines. which is an allergic reaction
hypersensitivity type 2
igG/igM
bind to the surface of a specific cell type marking it to be destroyed (autoimmune disease)(rohan)
