IMMUNOLOGY Flashcards
1
Q
the ability to ward off disease caused by microbes or their products and to protect against environmental agents
A
Immunity
2
Q
lack of immunity
A
Susceptibility
3
Q
response generated against a potential pathogen
A
Immune response
4
Q
– Immediate
– Notlong-lasting
– Nonspecific
– Lacks immunologic memory
– First line of defense
A
Innate Immunity
5
Q
– Responds rapidly to 2nd
exposure
– Specific
– Has immunologic memory
– Second line of defense
A
Adaptive Immunity
6
Q
Types of Innate Immunity
A
■ Skin and Mucous membranes
■ Formed Elements in the Blood
■ Lymphatic System
■ Complement System
■ Inflammation and Fever
■ Interferons
7
Q
Types of Skin and Mucous Membranes
A
■ Epidermis
■ Mucus in mucous membranes
■ Cilia in respiratory tract
■ Tears
■ Saliva
■ Flow of urine
■ Vaginal secretions
■ Defecation and vomiting
■ Sebum
■ Gastric acid
■ Lysozyme
■ Normal microbiota
8
Q
Types of Formed Elements in the Blood
A
■ Erythrocytes/RBCs
■ Leukocytes/WBCs
■ Platelets
9
Q
Myeloid stem cell (Granular leukocytes (white blood cells)
A
Erythrocyte
Megakaryocyte ->Platelets
Mast cell
Eosinophil
Basophil
Neutrophil
10
Q
Lymphoid stem cell (angular leukocytes (white blood cells)
A
Monocyte -> Dendritic cell, Macrophage
T-cell
B-cell -> Plasma cell
Natural killer cell
11
Q
Function: Phagocytosis
A
Neutrophils
12
Q
Function: Production of histamine
A
Basophils
13
Q
Function: Production of toxic proteins against certain parasites; some phagocytosis
A
Eosinophils
14
Q
Function: Phagocytosis (when they mature into macrophages)
A
Monocytes
15
Q
Functions: Phagocytosis and initiation of adequate immune responses
A
Dendritic cells
16
Q
Function: destroy target cells by cytolysis and apoptosis
A
Lymphocytes- Natural Killer cells
17
Q
ingestion of a microorganism or other substance by a cell
A
Phagocytosis
18
Q
– population of cells that descend from monocytes
A
Reticuloendothelial (Mononuclear Phagocytic) System
19
Q
Types of Reticuloendothelial (Mononuclear Phagocytic) System
A
Fixed Macrophages/Histiocytes
Free/Wandering Macrophages
20
Q
resident in certain tissues and organs of the body
A
Fixed Macrophages/Histiocytes
21
Q
roam the tissues and gather at sites of infection/inflammation
A
Free/Wandering Macrophages
22
Q
Types of Fixed Macrophages
A
■ Kupffer cells
■ Alveolar macrophages
■ Microglial cells
■ Langerhans Cells
■ Splenic macrophages
■ Peritoneal macrophages
23
Q
consists of a fluid (lymph), vessels (lymphatic vessels), and structures and organs
containing lymphoid tissue
A
Lymphatic System
24
Q
Types of Lymphatic System
A
Primary Lymphatic Organs
Secondary Lymphatic Organs
25
– where stem cells divide and become immuno competent
– e.g. bone marrow and thymus
Primary Lymphatic Organs
26
– where most immune responses occur
– e.g. lymph nodes, spleen, tonsils, Peyer’s patches, appendix, MALT (mucosa
associated lymphoid tissue)
– contains large numbers of lymphocytes and phagocytes
– Lymph nodes–sites of activation of T cells and B cell
Secondary Lymphatic Organs
27
*consists of >30 proteins produced by the liver that circulate in the
blood and within tissues
– inactive precursors: C1 through C9; activate by splitting
– active fragments :with lower case letters
Complement System
28
■ complements cells of the immune system in destroying microbes
■ acts in a cascade
Complement System
29
3pathways:all end inactivation of C3
– Classical
– Alternative
– Lectin
30
Outcomes of Complement Activation
-Cytolysis
-Opsonization
-Inflammation
31
■ a nonspecific, defensive response of the body to tissue damage
Inflammation
32
5 cardinal signs and symptoms in inflammation:
– Pain
– Redness
– Loss of function
– Swelling
– Heat
33
Functions:
– to destroy/remove the injurious agent
– if destruction/removal is not possible, to limit the effects on the body by confining or walling it off
– to repair or replace damaged tissue
Inflammation
34
Steps in Inflammation
Steps
1. Vasodilation and Increased Permeability
2. Phagocyte Migration and Phagocytosis
3. Tissue Repair
35
Two types of Inflammation
Acute and Chronic
36
– develop rapidly and last for
a few days or weeks
– mild and self-limiting
– principal defensive cells: neutrophils
Acute Inflammation
37
– develop slowly and last up
to several months or years
– severe and progressive
– principal defensive cells: monocytes and
macrophages
Chronic Inflammation
38
abnormally high body temperature due to resetting of the hypothalamic thermostat
Fever
39
– LPS from g( ) bacteria triggers phagocytes to release cytokines (IL-1, TNF-α)
Fever
40
– Cytokines trigger hypothalamus to release prostaglandins that reset the hypothalamic thermostat.
Fever
41
■ intensifies the effect of interferons
■ may help tissue repair
■ IL-1 - helps step up T cell production
Fever
42
■ a family of cytokines
■ produced by fibroblasts, lymphocytes and macrophages
■ inhibit viral replication
Interferons (IFNs)
43
3 types in humans:
– alpha interferon (IFN-ɑ)
– beta interferon (IFN-β)
– gamma interferon (IFN-γ)
44
has ability to differentiate between normal “self” cells and “nonself”
Adaptive Immunity
45
distinguished from innate immunity by its specificity and memory
Adaptive Immunity
46
refers to a component of the adaptive immunity where B cells secrete antibodies, which circulate in the blood as a soluble protein
Humoral Immunity
47
refers to the other component of the adaptive immunity, which is mediated by the activated, antigen-specific T cells
Cell mediated immunity
48
mediated by b cells (also by T cells and macrophages)
Humoral Immunity
49
mediated by t cells (also by helper t cells, cytotoxic t cells, natural killer cells, and macrophages)
Cell mediated immunity
50
acts on extracellular microbes and their toxins
Humoral Immunity
51
acts on intracellular microbes such as viruses, bacteria, and parasites and tumor cells
Cell mediated immunity
52
involves BCR receptors
Humoral Immunity
53
Involves TCR receptors
Cell mediated immunity
54
Iga, IgB, CD40, CD21, and Fc receptors are the accessory receptors
Humoral Immunity
55
CD2, CD3, CD4, CD8, CD28, and integrins are the accessory receptors
Cell mediated immunity
56
recognizes unprocessed antigens
Humoral Immunity
57
antigens are processed and presented by MHC complexes
Cell mediated immunity
58
plasma b cells secrete antibodies
Humoral Immunity
59
t cells secrete cytokines
Cell mediated immunity
60
rapid
Humoral Immunity
61
a delayed type hypersensitivity
Cell mediated immunity
62
does not act on the tumor cells and transplants
Humoral Immunity
63
acts on tumor cells and transplants
Cell mediated immunity
64
the process by which a lymphocyte proliferates (divides) and differentiates (forms more highly specialized cells) in response to a specific antigen
Clonal Selection
65
■ the formation of a clone of identical cells that can recognize the same specific antigen as the original lymphocyte
■ occurs in secondary lymphatic organs and tissues
Clonal Selection
66
2 Types of Clonal Cells
Effector Cells and Memmory Cells
67
– destroys or inactivates the antigen
Effector Cells
68
types of effector cells
*active helper T cells
*active cytotoxic T cells
*plasma cells
69
rapidly responds to the antigen during 2nd
exposure by rapid clonal selection
memory cells
70
types of memory cell
*memory helper T cells
*memory cytotoxic T cells
*memory B cells
71
substance recognized as foreign and provoke
immune responses; antibody generators
Antigen
72
protein produced in response to an antigen
Antibody
73
2 characteristics of Antigens
immunogenicity and reactivity
74
ability to provoke an immune response by
stimulating the production of specific antibodies, the proliferation
of specific T cells, or both
immunogenicity
75
ability of the antigen to react specifically with the antibodies or cells it provoked
reactivity
76
part of antigen that triggers immune responses and reacts with antibodies
epitope/antigenic determinant
77
■ either proteins or polysaccharides
■ MW≥10,000Da
■ Haptens
Antigens
78
LMW compounds that are antigenic when attached to a carrier molecule; has reactivity but no immunogenicity
Haptens
79
MHC stands for?
Major Histocompatibility Complex
80
■ a.k.a. human leukocyte antigen (HLA)
■ self antigens
■ transmembrane glycoproteins
Major Histocompatibility Complex
81
■ unique to an individual
■ present in all body cells except RBCs
■ help T cells recognize that an antigen is foreign, not self
Major Histocompatibility Complex
82
two types of MHC
MHC-I
MHC-II
83
present in all body cells except red
blood cells
MHC-I
84
present in antigen-presenting cells
(APCs)
MHC-II
85
3 kinds of Cell-Mediated Immunity
1. Processing of Antigens
– Exogenous Antigens
– Endogenous Antigens
2. Activation of T Cells
– Activation of Helper T Cells
– Activation of Cytotoxic T Cells
3. Elimination of Antigen
86
■ presentinfluids outside body cells
■ e.g., bacteria and bacterial toxins, parasitic worms, inhaled pollen and
dust, and viruses outside cells
■ processed by APCs
Processing of Exogenous Antigens
87
■ presentinside body cells
■ e.g., viral proteins produced after a virus infects the cell, toxins
produced from intracellular bacteria, or abnormal proteins
synthesized by a cancerous cell
■ processed by infected host cells
Processing of Endogenous Antigens
88
Activation of T Cells
– 1st Signal: antigen-MHC complexes
– 2ndSignal: cytokines e.g., IL-2
89
Cells Involved in Cell-Mediated Immunity
T helper cell (TH1, TH2, TH17)
Cytotoxic T Lymphocyte
T regulatory cell (T reg)
Activated Macrophage
Natural Killer cell
90
■ a subset of the helper T cells
■ carry an additional CD25 glycoprotein
Regulatory T Cell
91
Functions:
– combat autoimmune reactions by suppressing T cells that do not
distinguish between self and others
– protect normal flora
– protect the fetus during pregnancy
Regulatory T Cell
92
the immune system’s recognition of tumor antigens on cancer cells, and their destruction by cytotoxic T cells, macrophages, and NK cells
Immunological Surveillance
93
4 Process of Humoral Immunity
1. Processing of Exogenous Antigens
2. Activation of B Cells
3. Secretion of Antibodies
4. Elimination of Antigen
94
a.k.a. immunoglobulins (Igs)
Antibodies
95
■ can combine specifically with the epitope on the antigen that triggered its production
■ belong to a group of glycoproteins called globulins
Antibodies
96
4 polypeptide chains linked by disulfide bonds:
– 2heavy(H)chains–450AAs
– 2light(L) chains– 220Aas
97
2 regions in Antibodies :
– Variable (V)regions– contains the antigen-binding site
– Constant(C)regions– same in Igs of the same class
98
3 fragments in Antibodies:
– 2 Fab (fragment antigen-binding domain)– recognizes the antigen
– 1 Fc (fragment crystallizable domain)– binds to cell surface receptors
99
-Monomer
-80%
-Loc: Blood, Lymph, intestine
-Enhances phagocytes; neutralizes toxins and viruses protects fetus and newborn
IgG
100
-Pentamer
-6%
-Loc: Blood, lymph, B cell surface (as monomer)
-Especially effective against microorganisms and and agglutinating antigens; first antibodies produced in response to initial infection
IgM
101
-Dimer
-13%
-Loc: Secretions
-Localized protection on mucosal surfaces
IgA
102
-Monomer
-0.02%
-Loc: B cell surface, blood, lymph
-Serum function not known
IgD
103
-Monomer
-0.002%
-Loc: Bound to mast and basophils throughout body, blood
-Allergic reactions
IgE
104
due to the presence of long-lasting antibodies and very long-lived lymphocytes that
arise during clonal selection of antigen-stimulated B cells and T cells
Immunologic Memory
105
Memory T/B cells and can proliferate and differentiate into helper T cells, cytotoxic T
cells, or plasma cells within hours.
Immunologic Memory
106
can be measured by antibody titer - the amount of antibody in serum
– Primary response - After an initial contact with an antigen, a slow rise in the antibody titer occurs, first IgM and then IgG, followed by a gradual decline in antibody titer.
– Secondary response –After subsequent encounters, the antibody titer is far
greater than during a primary response and consists mainly of IgG antibodies.
Immunologic Memory
107
basis for vaccines
Immunologic Memory
108
refers to immunity, which results from the production of antibodies by the person's own immune systems in response to a direct contact of an antigen
Active Immunity
109
refers to a short-term immunity which results from the introduction of antibodies from the outside
Passive Immunity
110
Ways to Acquire Adaptive Immunity
1. Naturally acquired active immunity
2. Naturally acquired passive immunity
3. Artificially acquired active immunity
4. Artificially acquired passive immunity
111
a suspension of organisms or fractions of organisms used to induce immunity
Vaccines
112
– he deliberately inoculated people with cowpox to prevent smallpox in 1978
Edward Jenner
113
he coined the term vaccination (from L. vacca, meaning cow)
Louis Pasteur
114
for individual and community protection
Vaccines
115
– results when most of a population is immune to a disease
– outbreaks are limited to sporadic cases because there are not enough susceptible individuals to support the spread of
epidemics
– varies per disease
Herd Immunity
116
Types of Vaccines
Live Attenuated Vaccines and
Inactivated Vaccines
117
*living pathogen with reduced
virulence
*mimic actual infection (replicates
within the host)
*induce cellular and humoral
immunity
*lifelong immunity
*might mutate to a more
pathogenic form
*not for immunocompromised
people
Live Attenuated Vaccines
118
*do not replicate
*induce humoral immunity
*require booster doses
*safer than live vaccines
Inactivated Vaccines
119
8 Types of Inactivated Vaccines
Inactivated Killed Vaccines
Subunit vaccines
Toxoid vaccines
Polysaccharide Vaccines
Conjugated Vaccines
Nucleic Acid Vaccines
Viral Vector Vaccines
Virus-Like Particles
120
whole microbes that have been killed, usually by formalin or phenol
Inactivated Killed Vaccines
121
contain selected antigenic fragments
Subunit vaccines
122
contain inactivated toxins produced by the pathogen
Toxoid vaccines
123
contain molecules in a pathogen’s capsule
Polysaccharide Vaccines
124
contain polysaccharides combined with proteins
Conjugated Vaccines
125
contain DNA or mRNA that encodes for antigenic proteins
Nucleic Acid Vaccines
126
uses a nonpathogenic viral vector to deliver genetic material that encodes for antigenic proteins
Viral Vector Vaccines
127
contains viral proteins that mimic viral structure without genetic material
Virus-Like Particles
128
3 Diagnosis Reactions
Precipitation Reactions
Agglutination Reactions
Neutralization Reactions
129
involve the reaction of soluble antigens with
IgG or IgMantibodies
Precipitation Reactions
130
involve either particulate antigens or
soluble antigens adhering to particles
Agglutination Reactions
131
the presence of antibodies against a virus
can be detected by the antibodies’ ability to prevent cytopathic effects of viruses in cell cultures
Neutralization Reactions
132
■ the most widely used of a group of tests known as enzyme immunoassay (EIA)
■ 2 methods:
– Direct ELISA – detects antigens
– Indirect ELISA – detects antibodies
Enzyme-Linked Immunosorbent Assay
(ELISA)
133
■ an antigenic response that results in undesirable effects
■ represents immunological responses to an antigen (allergen) that lead to tissue damage rather than immunity
Hypersensitivity
134
■ immune system acts in response to self-antigens and causes damage
to one’s own organs
■ more common in women
Autoimmune Diseases
135
■ For T cells to function properly, they must have:– Self-recognition– Self-tolerance
■ Thymic selection– T cells that will target host cells are eliminated by clonal deletion in the thymus
■ Without self-tolerance, the body can produce autoantibodies or T cells that attack “self”.
Autoimmune Diseases
136
Types of Reactions to Transplantation
Organ Transplant
Graft
Graft rejection
Histocompatibility
Tissue typing (histocompatibility testing)
137
– involves replacement of an injured or diseased organ with an organ donated by another individual
Organ Transplant
138
– the transfer of a tissue from one part of the body to another, or from one person to another, without the transfer of the blood
supply of the grafted tissue
– Autograft
– Isograft
– Allograf
Graft
139
– recognition of transplanted organ as foreign and cell generation of cell mediated and antibody-mediated immune response
against it
Graft rejection
140
– the tissue compatibility between the donor and the recipient; based on MHC
Histocompatibility
141
– to reduce the risk of graft rejection
Tissue typing (histocompatibility testing)
