Gullo Exam 1 Flashcards
(121 cards)
Antigen Definition?
A substance that interacts specifically with any product of the immune system- not always productively
Pathogen definition?
living organisms (usually) that has the ability to cause disease- often has many potential antigens
Immunogen Definition?
an antigen that is recognized by the immune systems and leads to a productive response
What cell type is the largest proportion of leukocytes?
Neutrophils
Humoral Immunity refers to what broadly?
B Cells and their products (antibodies)
Cell-Mediated Immunity refers to what broadly?
CD8+ and CD4+ T Cells
Cytotoxic and Helper, respectively
Infants and Geriatrics share what in common about immune system?
Both weak immune systems
infants have no adaptive immunity, elderly have no new T cells
Explain Recognition Phase of Adaptive Immunity
involves processing of antigen by macrophages/dendritic cells
along with additional cellular interactions which lead to lymphocyte activation.
Explain Activation phase of Adaptive Immunity
involves proliferation and differentiation of lymphocytes
resulting in the expression of specific humoral and cell mediated immune effector functions.
Explain Effector phase of Adaptive Immunity
interaction of immune effector cells and molecules with antigen resulting in the elimination of antigen at the site of the infection.
Antigenic Determinant / Epitope Definition?
exact area of the recognition by B and T lymphocytes on the antigen
Most common antigen type?
proteins
T Cells can only ‘see’ what type of antigen?
peptides
B Cells can ‘see’ what type of antigens?
Chemicals Nucleic Acids Carbohydrates Lipids Peptides
Immunodominant Epitopes definition?
A single Pathogen can contain hundreds of antigens and a large number of immungens
only a set of them will be immundominant
Immunodominant epitopes are defined as those that dominate over others eliciting immune responses
Cross Reactivity and Penicillin
B-lactam ring of penicillin, cephalosporin, and carbapenems
some patients with a previous drug allergy to penicillin can develop drug allergy to cephalosporin
Penicillin can act as a hapten (non immunogenic) and can interact with RBC surface proteins. The combination of both can lead to the recognition of the new immunogen by B cells
Passive Immunization
Homologous hyper immune globulin (e.g. rabies)
Maternal to fetal transmission
Active Immunization
can be live or inactivated/killed. can be whole-cell, polysaccharides, or a subunit.
Explain Antigenic Sin
This process occurs with pathogens that have frequent variation in their antigen structures such as influenza
Immunodominant epitope dominate the response and often mask the new epitopes that on their own might otherwise elicit a response
Happens can only elicit an immune response when?
only capable of stimulating an immune response when bound to a carrier.
B-Cell Receptors are made up of what?
Membrane Bound Abs
Function of Secreted Abs
Neutralize toxins
Prevent the entry and spread of pathogens
Eliminate microbes
General Structural Properties of Ab
two heavy and two light chains held together by disulfide bonds with a ‘hinge’ region
Light Chains of Ab specific structural properties
constant (C) domain at the carboxyl half of the protein
variable (V) domain at the amino terminal half of the protein
Within the variable domain there are three sections with very high variability from protein to protein. Each section is called a complementarity determining regions (CDR) or hypervariable region.