Chapter 16 Flashcards
what is adaptive immunity
the body’s ability to
recognize and defend itself against distinct
invaders and their products
5 attributes of adaptive immunity
Specificity • Inducibility • Clonality • Unresponsiveness to self • Memory
2 types of adaptive immune responses
cell-mediated immune responses and antibody immune responses (humoral immunity)
primary and secondary lymphoid organs
primary- red bone marrow and thymus
secondary- lymph nodes, spleen, tonsils, and mucosa-associated lymphoid tissure (MALT)
properties of antigens
Molecules the body recognizes as foreign and
worthy of attack
• Recognized by three-dimensional regions called
antigenic determinants/epitopes on antigens
• Large foreign macromolecules make the best
antigens
• Include various bacterial components as well as
proteins of viruses, fungi, and protozoa
types of antigens (3)
exogenous, endogenous, and autoantigens
define exogenous antigens
Exogenous antigens— include toxins and other components of microbial cell walls, membranes, flagella, and pili
define endogenous antigens
—produced by
microbes that reproduce
inside a body’s cells
define autoantigens
derived
from normal cellular
processes
Roles of the Major Histocompatibility Complex
(MHC) and Antigen-Presenting Cells
• Group of antigens first identified in graft patients
• Important in determining compatibility of tissues for tissue
grafting
• Major histocompatibility antigens are glycoproteins found
in the membranes of most cells of vertebrate animals
• Also know as human leukocyte antigen (HLA) system
• Hold and position antigenic epitopes for presentation
to immune cells
2 classes of MHC proteins
MHC class I- present on all cells except RBCs MHC class II- Present on antigen-presenting cells (APCs) • APCs include-macrophages and dendritic cells
describe T lymphocytes
Produced in the red bone marrow and mature in the thymus • Circulate in the lymph and blood • Migrate to the lymph nodes, spleen, and Peyer’s patches • Have T cell receptors (TCRs) on their cytoplasmic membrane
3 types of T lymphocytes
cytotoxic t cells, helper t cells, and regulatory t cells
cytotoxic cells ____
directly kill other cells
helper T cells regulate ______
B cells and cytotoxic t cells
what do regulatory t cells do
represses adaptive immune responses
four fates that immature t cells undergo
T cells that do not recognize body’s MHC protein undergo
apoptosis
• T cells that recognize autoantigen die by apoptosis
• Some “self-recognizing” T cells become regulatory
T cells
• T cells that recognize MHC protein and foreign epitopes
become repertoire of protective T cells
b cells are found primarily in the ______
spleen, lymph nodes and MALT
major function of B cells
secretion of antibodies
each b lymphocyte has multiple copies of the ____
B cell receptor (BCR)
antibodies are ______similar to BCRs
immunoglobulins
what region of the antibody contains the antigen-binding sites
the arms or the Fab region( fragment antigen binding)
the antibody stem is called
Fc region (fragment, crystallizable)
5 basic types of stems and these form the 5 classes of antibodies which are
IgM, IgG, IgA, IgE, and IgD
antibody class involved in the immune response varies by
type of antigen, portal of entry, and antibody function needed
describe IgG
—most common and longest-lasting antibody
describe IgA
associated with body secretions
describe IgM
first antibody produced
describe IgD
exact function is not known
Describe IgE
involved in response to parasitic infections and allergies
list the several ways antibodies function
-Activation of complement and inflammation
• Neutralization
• Opsonization
• Agglutination
• Antibody-dependent cellular cytotoxicity
(ADCC)
where does clonal deletion of b cells occur
in bone marrow
cytokines secreted by various _____
leukocytes
what is the cytokine network
complex web of signals among cells of the immune system
interferons are _________ ______ that may act as cytokines
antiviral proteins
growth factors are
proteins that stimulate stem cells to divide
what is the tumor necrosis factor (TNF)
• Secreted by macrophages and T cells to kill tumor
cells and regulate immune responses and
inflammation
what are chemokines
chemotactic cytokines that signal leukocytes to move
steps involved in activation of cytotoxic t cells
- Antigen presentation
- Helper T cell differentiation
- Clonal expansion
- Self-stimulation
two pathways cytotoxic t cells kill targets
perforin-granzyme pathway and CD95 Cytotoxic pathway
cytotoxic t cells destroy their targeted cells by secreting what toxic protein molecules
perforins and granzymes
CD95 cytotoxic pathway is mediated through______
glycoprotein on bodys cells
memory response is _____ effective than the primary response
more
T-dependent antibody immunity depends on the function of _______
helper t cells
four steps of this immune response
- Antigen presentation for Th activation and
proliferation - Differentiation of helper T cells into Th2 cells
- Activation of B cells
- Proliferation and differentiation of B cells
what are the majority of cells produced during b cell proliferation
plasma cells
plasma cells are
short lived cells that can die within a few days
2 types of acquired immunity
naturally acquired and artificially acquired
describe naturally acquired immunity
response against antigens encountered in daily life
describe artificially acquired immunity
Response to antigens introduced via a vaccine
define active immunity
results when a person is
challenged with antigen that stimulates production
of antibodies; creates memory, takes time, and is
lasting
describe passive immunity
preformed antibodies are
donated to an individual; does not create
memory, acts immediately, and is short term
Naturally acquired active immunity
resulting from infection
Naturally acquired passive immunity
Mother to child: Transplacental or via colostrum
Artificially acquired active immunity
vaccination
Artificially acquired passive immunity
Injection of antibodies (immune serum Gamma
() globulin) to protect against helaptitis A,(copied this from her slide idk if she meant hepatitis lmfao)
rabies, tetanus etc
