Immunity Flashcards
1
Q
2 factors in Host – parasite relationship
A
- Properties of the parasite that enable them to produce disease
- Mechanisms by which the host defends itself against the parasites.
2
Q
also influence the host-parasite relationship
A
environment
3
Q
The most common successful host-parasite relationship is our own
A
microbial flora
4
Q
Unsuccessful host-parasite relationship results to
A
infectious disease
5
Q
– colonization of organisms in the host
A
infection
6
Q
follows infection only if the presence of microorganisms or its products directly injure the host’s tissues. Usually produce signs and symptoms of the illness
A
disease
7
Q
Mechanisms by which the host defends itself in the presence of invaders
A
I. Nonspecific host defense mechanisms
II. Specific host defense mechanisms
8
Q
A. Humoral immune response
B. Cellular immune response
A
II. Specific host defense mechanisms
9
Q
Barriers in the host against microorganisms:
A
- first barrier
- inflammation
- lymphatic system
10
Q
gross surface area which are the: skin, respiratory tract, gastrointestinal tract, genitourinary tract
A
first barrier
11
Q
- intact skin is impenetrable to most pathogenic microorganisms
- desquamation
- simple drying
- fatty acids
A
skin
12
Q
- integrity of mucosal lining
- peristaltic movement of intestine
- defecation
- acid pH of gastric secretion
A
gastrointestinal tract
13
Q
- hairs in the anterior nares
- cilia of respiratory mucosa
- mucous secretions
- sneezing, coughing, epiglottic reflex
A
respiratory tract
14
Q
- intact mucous membranes
- act of urination
- acid pH of urine, vaginal secretion
A
genitourinary tract
15
Q
- a complex cellular response which varies with the specific type of organisms
A
INFLAMMATION
16
Q
- polymorphonuclears (neutrophils). Macrophages, lymphocytes, plasma cells eosinophils
- phagocytosis is an important event in inflammation
A
cells participating in an inflammatory response
17
Q
- lymphatic vessels and lymph nodes
- filters microorganisms
A
lymphatic system
18
Q
the disease producing ability of the organisms
A
pathogenicity or virulence
19
Q
Pathogenic properties of microorganisms
A
1.ability to attach to epithelial cells
2. virulence factors that promote pathogen survival and host tissue injury
3. ability to produce toxins
4. capacity for genetic change
20
Q
– specific
Ex. Pili of Neisseria gonorrhoeae
A
ability to attach to epithelial cells
21
Q
The capsule of certain bacteria protects them from phagocytosis
A
antiphagocytic factor
22
Q
Hyaluronidase enzymes dissolve hyaluronic acid which form the cement substance between cells therefore facilitating the spread of inf.
A
spreading factor
23
Q
virulence factors that promote pathogen survival and host tissue injury
A
- antiphagocytic factor
- spreading factor
24
Q
ability to produce toxins – 2 types
A
exotoxins
endotoxins
25
– polypeptide in nature
- highly antigenic
- relatively unstable to heat
exotoxins
26
exotoxins, biologic activities:
a. cytotoxic effects
b. inhibition of protein synthesis
c. interference with neuronal transmission
d. effects on the transport of ions and water across cell membrane
27
– lipopolysaccharide in nature
- weakly antigenic
- relatively stable to heat
endotoxins
28
endotoxins, biologic activities:
a. production of fever
b. produce septic shock
c. leukopenia
29
– ability of organisms to undergo mutation
capacity for genetic change
30
the study of immunity
IMMUNOLOGY
31
- ability of the immune system of the host to recognize antigens as self or nonself
- means resistance to infection
immunity
32
reverse of immunity
susceptibility
33
Kinds of immunity
1. Natural
a. species
b. racial
c. individual immunity
2. acquired
a. active
b. passive
34
Kinds of immunity
- innate, inherited
natural
35
Kinds of immunity
- acquired throughout the lifetime of the host
acquired
36
human/animal species
species
37
brown/white race
racial
38
Acquired Immunity, Active
- active infection, subclinical infection
natural
39
Acquired Immunity, Active
- immunization or vaccination
artificial
40
Acquired Immunity, Passive
- placental transfer of antibodies
- colostrum of milk
natural
41
Acquired Immunity, Passive
- administration of preformed antibodies
artificial
42
Immune responsiveness of the host is controlled by the ___ (HLA) complex or system in man which is located in the short anm of chromosome 6
human leukocyte antigen
43
Major Fucntions of the Immune System
1. defense
2. homeostasis
3. surveillance
44
increased susceptibility to infection
hypofunction
45
allergy or hypersensitivity
hyperfunction
46
removal of worn-out cells or damaged cells
homeostasis
47
– autoimmune diseases
hyperactivity
48
– recognition and removal of abnormal mutant cells
surveillance
49
– development of tumor and malignancy or cancer
failure
50
IMMUNOCYTOLOGY
Cells of the immune system belong to:
1. Hematopoietic system
2. Mononuclear (Monocytic) Phagocytic system
3. Granulocytic system
4. Lymphoid system
51
Hematopoietic system
bone marrow stem cells -> non lymphoid precursor cells -> erythrocytes, thrombocytes, monocytes, granulocyes
bone marrow stem cells -> lymphoid precursor cells -> lymphocytes -> b cells & t cells
52
Cells mainly involved in immune responses:
1. Lymphocytes
2. Monocytes
3. Granulocytes
53
- known before as reticuloendothelial system
- principal cells are monocytes and macrophages
- - main function is phagocytosis; most efficient phagotic cells are macrophages
monocytic phagocytic system
54
- circulating in the blood
- comprises 1-3% of total WRC
- migrate to the tissues as macrophages
- macrophages known by different names in the tissues
monocytes
55
connective tissues
histiocytes
56
– liver
kupffer cells
57
lungs
alveolar macrophages
58
most efficient phagotic cells are
macrophages
59
– 5,000 to 10,000 cells/cu mm blood
WBC (white blood cell) count
60
– increase, seen in acute bacterial infection
leukocytosis
61
– decrease, viral infection
leukopenia
62
– neutophils, lymphocytes, monocytes, eosinophils, basophils
differential count
63
Granulocytic Phagocytes
- cytoplasm filled with granules
1. neutrophils
2. eosinophils
3. basophils
64
- 60 to 70% of total WBC count
- most predominant phagocytic cells in the peripheral blood
- increased in acute bacterial infection (neutrophilia)
neutrophils
65
increased in acute bacterial infection
neutrophilia
66
- 3%
- increased in parasitism and allergy
- less efficient phagocytic activity
eosinophils
67
- 1%
- granules contain chemical mediator such as histamine
basophils
68
– ingestion of microorganisms or other foreign substances by phagocytic dells
phagocytes
69
stages of phagocytes
1. recognition
2. attachment
3. invagination of cell membrane and formation of phagocytic vacuole pr phagosome
4. fusion of phagosome with lysosomal granules forming the phagolysosome, rupture of lysosome releasing its digestive enzymes into the phagosome, initiating the killing and digestion of foreign substance.
5. extrusion of digestive debris.
70
Lymphoid system
Classification of lymphoid organs and tissues
1. central or primary
2. peripheral or secondary
71
a. Bone marrow
b. thymus
central or primary lymphoid organs & tissues
72
a. lymph mode
b. spleen
c. bone marrow
d. GALT (gut-associated lymphoid tissue) and MALT (mucosa-associated lymphoid tissue)
peripheral or secondary lymphoid organs & tissues
73
- tonsils, Peyer’s patches, appendix
GALT (gut-associated lymphoid tissue) and MALT (mucosa-associated lymphoid tissue)
74
site of differentiation and maturation of B lymphocytes
- also a secondary lymphoid organ because it can be an important source of antibodies
Bone marrow
75
– important organ in the young
- fully developed and functional at birth
- site of differentiation and maturation of T lymphocytes
- master organ of the immune system
thymus
76
– oval or bean-shaped structures that are regularly distributed throughout the lymphatics
- filter foreign substances from the lymph
- lymphadenopathy(enlargement); lymphadenitis (inflammation)
lymph node
77
– largest mass of lymphoid tissues
- filters substances from the blood
- considered as graveyard of dying red cells
spleen
78
- principal cells of the lymphoid system
- 30%
lymphocytes
79
2 types of lymphocytes
B & T Lymphocytes
80
- 70-80%
- thymus
- long-lived
- bald
t lymphocytes
81
- 20%
- bone marrow
82
- 20%
- bone marrow
- variable
- hairy
b lymphocytes
83
Specific immune responses
2 mechanisms that mediate a specific immune response:
1. Humoral (antibody-mediated or AMI)
2. Cellular (cell-mediated or CMI)
84
- governed by B lymphocytes
- body’s main defense against bacterial infections
Humoral immune response
85
activation of B lymphocytes by appropriate antigen results to proliferation into 2 groups of cells
- plasma cells
- memory B cells
86
– responsible for direct synthesis of antibodies
plasma cells
87
responsible for a more rapid secondary immune response
memory B cells
88
- Substance that can combine with specific antibody
- substance that can stimulate a specific immune response
- not recognized by the immune system as self
- most are proteins, others are polysaccharides
Antigen (Ag)
89
- special forms of proteins that are produced upon antigenic stimulation of B lymphocytes
- high concentration in serum of the blood
- can be detected in the other body fluids like tears, saliva, urine, milk, cerebrospinal fluid, gastric secretions
Antibody (Ab) or immunoglobulins (Ig)
90
Classes of immunoglobulins:
1. IgG
2. IgA
3. IgM
4. IgE
5. IgD
91
– most abundant
- longest life span
- most important protective antibodies
- pass through the placenta
IgG
92
– second most abundant
- predominantly found in body fluids and portals of entry
IgA
93
– largest antibody
- produced by fetus in utero, elevated during intrauterine infections
IgM
94
– very low concentrations in the serum
- very little biologic functions
IgD
95
– very low concentration in the serum
- responsible for the immediate type of allergy
IgE
96
- Y-shaped
- antibody binding site
- a pair of heavy chain and a pair of light chain
- disulfide bonds
Ig
97
- governed by thymus dependent T lymphocytes
- plays a central role in defense
cellular immune response
98
activation of T cells by appropriate antigen results to :
1. generation of T cells subsets
2. release of immunoregulatory substances called cytokines which act as molecular signals in between immune cells
3. memory T cells
99
T helper cells, T cytotoxic cells, T suppressor cells, T contrasuppressor cells, T delayed type hypersensitivity cells
T cells subsets
100
1. further activation of macrophages so they have more ability to destroy phagocytosed organisms
2. cooperate with B lymphocytes in antibody production
3. cancer surveillance
4. graft rejection
5. delayed hypersensitivity reaction
6 defense against infections with acid fast organisms, fungal infections and termination of an ongoing viral infection
cellular immune response
101
Characteristics of specific immune response
1. highly specific
2. wide variety of cell types and cell products that interact to produce an immune response
3. memory
102
- harmful or unpleasant effect of immunity
- immune response that injure or damage the host instead of protecting the host
allergy (hypersensitivity)
103
– antigenic substance that can trigger allergy
- the tendency to develop allergy is hereditary
allergen
104
allergen may reach the body via:
1. respiratory route
2. gastrointestinal tract
3.direct contact with skin or mucous membranes
4. mechanical injection
105
kinds of allergy
1. immediate type (type 1)
2. delayed type (type IV)
106
- antibody-mediated
- clinical types:
a. skin urticaria and hives
b. allergic rhinitis
c. bronchial asthma
d. anaphylactic shock
e. immediate type of skin test
immediate type (type 1)
107
- cell-mediated
- clinical types:
a. contact allergy or dermatitis
b. tuberculin test
delayed type (type IV)
108
allergy to tubercle bacili
tuberculin test
109
Allergen enter the body via portals of entry -> stimulate the production of specific IgE -> IgE attach to surface of mast cells (and basophils)
First exposure (sensitizing dose)
110
Allergens combine with IgE attached to mast cells -> degranulation of mast cells -> release of highly active chemical mediator known as vasoactive amines, most important is histamine
Second or subsequent exposure to some allergen (challenging or provocative dosse)
111
responsible for the signs and symptoms of allergy
vasoactive amines
112
1. Contraction of smooth muscles
2. increase gastric secretions
3. increase in nasal and lacrimal secretions
4. increase vascular permeability
5. vascular changes leading to vascular collapse
effects of vasoactive amines
113
immune reaction against self-antigens
autoimmune diseases
114
- multisystem disease of autoimmune origin characterized by the presence of autoantibodies particularly anti-nuclear antibodies
Systemic lupus erythymatosus (SLE)
115
- severe form of chronic synovitis that sometimes lead to destruction of affected joints
- circulating autoantibodies called rheumatoid factor (RF) against an altered IgG
Rheumatoid arthritis
116
- autoantibodies against thyrocytes
Hashimoto’s thyroiditis
117
- autoantibodies against the islet cells of the pancreas
Insulin-dependent diabetes mellitus
