Antigens and Haptens Flashcards
Any substance that can induce humoral and/or cell mediated immune responses when introduced to an individual or animal is known as _____.
Antigen
All of the following are microbial antigens except:
a. Bacteria
b. Helminth parasites
c. Foreign proteins
d. Protozoa
c. Foreign proteins
**non-microbial antigens
Antigens found in genetically identical individuals is known as:
a. Autologous antigens
b. Allogenic antigens
c. Isogenic antigens
d. Xenogenic antigens
c. Isogenic antigens
Antigens that are found within different species of animals is known as:
a. Autologous antigens
b. Allogenic antigens
c. Isogenic antigens
d. Xenogenic antigens
d. Xenogenic antigens
Antigens that are found within the same individual are knonw as:
a. Autologous antigens
b. Allogenic antigens
c. Isogenic antigens
d. Xenogenic antigens
a. Autologous antigens
A non-antigenic molecule usually of low molecular weight that by itself can’t induce an immune response but can react with the products of that response is known as ____.
Hapten
Antigens that are found in genetically dissimilar members of the same species are known as:
a. Autologous antigens
b. Allogenic antigens
c. Isogenic antigens
d. Xenogenic antigens
b. Allogenic antigens
True/False: The more complex a molecule the more varied the epitope composition and the more likely different immune responses will be induced.
True
True/False: Polysaccharides are considred the most complex organic compounds and therefore the most antigenic.
False
**proteins are, polysaccharides are weak antigens b/c they don’t possess sufficient chemical complexity
True/False: The more foreign the antigen the more vigorous the immune response.
True
Antigens that are ___ have many epitopes with different specificities vs ___ which have many epitopes with the same specificity.
Polyvalent - different specificity
Multivalent - same specificity
Which of the following is false regarding heterophile antigens?
a. They can cross-react with an unrelated antigen
b. Two unrelated antigens share one or more identical or very similar epitopes
c. The affinity of the antibody for the cross reacting epitope is usually greater than that for the original epitope
d. Moon blindness in equines (corneal edema and ulceration) is an example of this
c. The affinity of the antibody for the cross reacting epitope is usually greater than that for the original epitope
***usually less than that for the orignial epitope
True/False: Hapents always have to be coupled to a carrier substance in order to produce an immune response.
True
What are autocoupling haptens?
Haptens that form spontaneous covalent bonds with self proteins to create new antigens.
Helper T cells recognize foreign antigens on the surface of ____ and present them in the groove of ____.
APC, MHC II
What kind of cells do cytotoxic T cells recognize antigen on?
Virus infected and tumor cells
Cytotoxic T cells present antigens in the groove of which MHC class?
MHC I
Which of the following is false regarding superantigens?
a. They don’t lead to acquired immunity and have no memory
b. They are active at high concentrations and release small amounts of cytokines
c. Cytokine release causes systemic toxicity
d. Stimulation is not specific for the pathogen and regardless we have massive T cell activation
b. They are active at high concentrations and release small amounts of cytokines
**active at low concentrations and release large amounts of cytokines
Which of the following is false?
a. BCR’s can be secreted in plasma as antibodies
b. TCR’s have grooves that bind small pepties presented by MHC on surface of APC’s
c. MHC molecules are essential for presentation of peptides so they can recognize and bind to TCR’s
d. All the above are true
d. All the above are true
What is an immunogen?
Antigens that stimulate an immune response
True/False: All antigens are immunogens.
False
**all immunogens are antigens but not all antigens are immunogens
What is an adjuvant?
Molecules that interact with the immune response to make a molecule that is not antigenic more antigenic and therefore enhance the immune response
Which theory is based on cells that possess antigen receptors that can react with specific infectious agents and specificity was determined prior to antigen exposure?
Selective theory
When an antigen telsl the body what shapes to make the binding sites on the antibody molecule is referred to as the ____ theory.
Instructional theory
