Acquired Immune Response Flashcards
define acquired immunity
the resistance of a host resulting from the formation of antibodies or anti-body like responses
what are the 2 parts of the immune response?
- Humoral antibody response
- cell-mediated immune response
define the Humoral antibody response
- responses that lead to the formation of antibody molecules that circulate with the body fluids.
define cell-mediated immune response
the production of lymphocytes that have specific reactive sites
define antigen
any foreign substance that stimulates the formation of antibodies (usually proteins or carbohydrates over 10 kDa, some lipids)
define antibody
a substance that will specifically combine with only the type of antigen called antigenic determinants
why cant an antigenic determinant stimulate antibody formation alone?
- it cant because of its small size but it can react with antibodies already formed
Humoral antibodies are released into the…
blood and are found in most tissue fluids
Humoral antibosdies destroy…
invading organisms or neutralize toxins
what the 1st step in humoral antibody response?
a bacterium with a specific antigenic determinant is phagocytized by a microphage in a lymph node or lymphatic organ
what the2nd step in humoral antibody response?
the foreign substance (antigen) is presented to a B cell which has a specific receptor that combines. When the B-cell combines with its specific antigen it becomes activated and begins to multiply AKA clonal expansion.
what the 3rd step in humoral antibody response?
A helper T cell is involved in this process
what the 4th step in humoral antibody response?
activated B cells differentiate into either memory lymphocytes or plasma cells
what the 5th step in humoral antibody response?
plasma cells contain increased cytoplasm, ER, and ribosomes produce proteins called immunoglobulins(Ig) or antibodies
what the 6th step in humoral antibody response?
memory cells replicate to a limited extent and become involved with secondary antibody responses.
what are the classes of immunoglobulins or antibodies?
IgG IgM IgA IgD IgE
IgG
…
IgM
….
IgA
…
IgD
…
IgE
…
In the humoral antibody response, when does the antibody appear in detectable levels
week 1 after exposure to antigen
(Primary) Maximum antibody concentration is attained at week ____ and what happens over the years at this level?
3;
the level of antibodies slowly decrease over the yearsc
what happens when a person who has had a primary antibody response is re-exposed to the same antigen?
- IgG and IgA are produced in a few days rather than a few weeks. The preprogrammed memory cells( which last for years) rapidly change into antibody-producing plasma cells before the invading organism has a chance to produce a clinical disease.
what are the 4 ways the antibodies function against microorganisms?
- agglutination
- neutralizing antibodies
- antitoxins
- activation of the complement system
define the agglutination reaction
antibodies bind microorganisms into clumps by forming bridges between cells. These cells are readily phagocytized
what occurs when neutralizing antibodies?
combine over the surface of microorganisms and prevent their attachment to host cells
How do antitoxins function against microorganisms?
antitoxins form antibodies that neutralize toxins produced by microorganisms
- activation of the complement system
…
