Immunology 1 Flashcards

(215 cards)

1
Q

This exists to protect the host from infection

A

Immune system

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2
Q

This is the ability of an organism to resist a particular infection or toxin by the action of specific antibodies or sensitized white blood cells

A

Immunity

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3
Q

This is a collection of cells, tissues, and molecules that mediate resistance to infections

A

Immune system

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4
Q

Primary function of the immune system

A

Surveillance → recognition of self from non-self → identification of foreign or pathogenic invaders → attack and elimination

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5
Q

This is a coordinated reaction of the immune cells and molecules to infectious microbes

A

Immune response

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6
Q

The study of molecules, cells, organs & systems responsible for the recognition & disposal of what is foreign or non-self

A

Immunology

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7
Q

How body components respond to foreign materials and how they interact

A

Immunology

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8
Q

It deals with understanding the desirable (protective) and the undesirable (pathologic)

A

Immunology

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9
Q

It deals with ways by which the immune system can be manipulated to protect the body against diseases by preventing the invasion of infectious agents or to treat diseases by eradicating established infections.

A

Immunology

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10
Q

Founder of Immunology
Father of Vaccinology
Initiated vaccination - first reliable method of conferring lasting immunity to smallpox

A

Edward Jenner

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11
Q

This is defined as “the phenomenon in which exposure to one agent produces protection against another agent (Stevens)”
Cowpox and smallpox

A

Cross-immunity

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12
Q

The person who defined cross reactivity as “the phenomenon in which exposure to one agent produces protection against another agent (Stevens)”

A

Louis Pasteur

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13
Q

This may occur through heat, aging, or chemical means, and it remains the basis for many of the immunizations that are used today.

A

Attenuation or change

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14
Q

Year when spread of vaccination (first rabies vaccine given to a young boy bitten by a rabid dog)

A

1885

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15
Q

Year when immunology began

A

1796

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16
Q

Discovered antibodies while developing a diphtheria antitoxin

A

Eml Von Behring & Shibasaburo Kitasato

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17
Q

True or False.

Tetanus poisons can be given to patients to cure them from this disease.

A

True

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18
Q

Year when antibodies protect against disease

A

1901

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19
Q

Developed a way to make pure culture of bacteria and discovered cholera bacterium and Mycobacterium tuberculosis

A

Robert Koch

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20
Q

Year when immune response to tuberculosis started

A

1905

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21
Q

Demonstrated that protective effects of the immune system could also cause great damage to the body
Worked on anaphylaxis

A

Charles Richet

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22
Q

Discovered the ABO blood group and Rhesus factor (Rh)

A

Karl Landsteiner, 1930

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23
Q

Year when there is vaccine against Yellow Fever

A

1951

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24
Q

Year of the development of antihistamine drugs for allergy treatment

A

1957

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25
Year when the structure of the antibody molecule revealed
1972
26
Year of the development of monoclonal antibody
1984
27
Year when Hepatitis B vaccine was discovered
1986
28
Year of the Transplantation immunology
1991
29
Year when Human Papilloma Vaccine started to prevent Cervical Cancer
2005
30
A complex collection of fluid and cells that penetrate all the organs, tissue spaces, vascular network and fluid compartments of the body “Soldiers” that protect the body
Immune system
31
Organs of defense and immunity
Reticuloendothelial system (RES) Extracellular fluid (ECF) Bloodstream Lymphatic System
32
A network of connective tissue fibers inhabited by macrophages that attack and ingest microbes
Reticuloendothelial system (RES)
33
Surrounds all tissue cells; penetrate by blood and lymph vessels
Extracellular fluid (ECF)
34
Contains specific and non-specific cellular defenses
Bloodstream
35
Brings all components of the second and the third line of defense to attack infectious microbes
ECF
36
It provides the route of passage for macrophages while waiting for the foreign substances
RES
37
Functions of the lymphatic system
Returns tissue fluids to the general circulation Carries away excess fluid in inflamed tissues Concentrates and processes foreign invaders Initiates the specific immune response
38
This involves further differentiation into monocytes, granulocytes (neutrophils, eosinophils, basophils), RBCs and thrombocytes.
Myeloid series
39
This is responsible for the production of the lymphocyte, and the natural killer (NK) cells which is also known as the large granular lymphocyte.
Lymphoid series
40
Site of maturation of T and B cells
Primary lymphoid organs
41
Two primary lymphoid organs
Bone marrow | Thymus
42
Bone marrow or Thymus. | Responsible for providing the stem cells from which the blood cells arise
Bone marrow
43
Bone marrow or Thymus. | Located near the heart
Thymus
44
Bone marrow or Thymus. | Produces humoral factors that will induce immunological competence in lymphocytes
Thymus
45
Bone marrow or Thymus. | Site of maturation for B cells
Bone marrow
46
Bone marrow or Thymus. | Site of maturation for T cells
Thymus
47
Bone marrow or Thymus. | Its equivalence in chickens is the Bursa of Fabricius
Bone marrow
48
Secondary lymphoid organs
``` Spleen Lymph nodes (LN) Peyer’s patches Tonsils Appendix SALT (skin-associated lymphoid tissue) MALT (mucosa-associated lymphoid tissue) GALT (gut-associated lymphoid tissue) ```
49
Serve as an antigen trapping site of tissues or vascular spaces and the site where mature lymphocytes can interact effectively with the antigen
Secondary lymphoid organs
50
Lymphocytes circulate through these organs so that every antigen is exposed to a sample of the whole lymphocyte population (of B cells or T cells)
Secondary lymphoid organs
51
Carry products of the immune response such as antibodies and T cells to the blood and/or tissues
Secondary lymphoid organs
52
Two major cellular components of the immune system
Agranulocytes | Granulocytes
53
Two agranulocyte cells
Lymphocytes | Monocytes
54
Central cell of the immune system
Lymphocytes
55
20-25% of the WBC in blood | 99% of cells in lymph
Lymphocytes
56
Composed of T cells, B cells and NK cells
Lymphocytes
57
True or False. | Lymphocytes are the only WBC that produce specific receptors for antigens
True
58
True or False. | Lymphocytes are morphologically similar but extremely heterogenous in lineage, function, and phenotype
True
59
Manner by which lymphocytes are distinguish
Cluster of differentiation (CD)
60
Important features of lymphocytes
Restricted cell surface receptors Clonal proliferation (able to produce similar cells) Long life span: memory cells Recirculation between tissues and blood, assuring body wide distribution
61
This is the ability of lymphocytes to recognize differences between antigens
Specificity
62
True or False. | Basal cells have antigen binding receptor to recognize the antigen.
True
63
True or False. | T-helper cells have T cell receptor (TCR) molecule that functions like the immunoglobulins.
True
64
Have TCR and CD4
Th
65
Have TCR and CD8
Tc
66
T or B cell. | 15%-20% of lymphocytes in the blood
B cell
67
T or B cell. | 75%-80% of lymphocytes circulating in the blood
T cell
68
T or B cell. | Associated with humoral immunity
B cell
69
T or B cell. | Function: differentiates into antibody-producing plasma cells in the presence of an antigen
B cell
70
True or False. | Other lymphoid stem cells migrate from the bone marrow to the thymus, thereby undergoing specialization into T cells.
True
71
T or B cells. | Found in all lymphoid tissues, especially in the paracortical region of the lymph nodes
T cells
72
T or B cells. | Develops first from lymphoid stem cells in the liver of fetuses
B cells
73
T or B cell. After birth, they develop and mature from lymphoid stem cells in the bone marrow where they mature containing IgM and IgD
B cell
74
T or B cell. | Long life span
T cells
75
T or B cell. After maturation, they migrate to the lymphoid tissue, lymph nodes (specifically in the cortical region), spleen, tonsils, adenoids, & GALT.
B cells
76
End product of B cell activation
Antibodies
77
T cells differentiate into
Td, Tc, Th, Ts
78
Both T cell differentiated cells function for cell mediated immunity and antigen clearance.
Td and Tc
79
Both T cell differentiated cells function as regulatory cells.
Th and Ts
80
T cell associated with delayed type hypersensitivity
Td
81
Cytotoxic T cells
Tc
82
Suppressor T cells; down regulates immune system
Ts
83
T helper cells; aid in the enhancement of the immune system
Th
84
T cells that provide chemical signals that help stimulate other immune cells like B lymphocytes to differentiate into Ab-producing cells
Th cells
85
T cell that produce cytokines that regulate activities of T cells & B cells, monocytes & other immune cells
Th
86
Th differentiates into
Th1 | Th4
87
Th1 cytokine that activate macrophages or help B cells to switch to IgG synthesis
TNF-γ
88
Th2 cytokine that activate mast cells, eosinophils and causes B cells to synthesize IgE
IL-4
89
``` True or False. CD4 molecules displayed on the surface of the T cells are able to recognize a non-peptide bonding portion of MHC class II molecule. ```
True
90
Normal ratio of CD4+ to CD8+ cells
2:1
91
T cells that identify cells infected with intracellular organisms and eliminate or lyse the cells harboring them
Tc cells
92
T cell that kills tumor cells, host cells infected with viruses, and other microorganisms
Tc cells
93
T cell involved in other types of allergic reactions
Tc cells
94
``` True or False. CD8 molecules displayed on the surface of these T cells recognize the non-peptide bonding portion of MHC class I molecule. ```
True
95
T cells that function to downregulate thus control the adaptive immune responses
Ts cells
96
15% of blood lymphocytes Large lymphocytes that have Killer Activation Receptors (KARs) and Killer Inhibition Receptors (KIRs), but do not have membrane surface markers
NK cells
97
Function of NK cells
Destroy target cells by cytolysis and apoptosis
98
True or False. NK cells normally circulate in the blood but can migrate to infected tissues and kill infected host cells but do not express the kinds of clonally distributed antigen receptors that B cells and T cells do.
True
99
Type of surface protein that is lacking in NK cells
MHC class 1
100
Lymphocytes that kill foreign cells, viral infected cells, tumor cells and produce cytokines that stimulate macrophages
NK cells
101
3-7% in the circulation | Phagocytes that develop from the myeloid series; considered as an agranulocyte
Monocytes
102
Largest WBC and develop into macrophages when they leave the circulation
Monocyte
103
Morphology of monocytes
Nucleus is oval or kidney-shaped | “Ground glass” appearance
104
Functions of macrophages
Phagocytosis | Secrete cytokines that influence growth and activation of other cell types
105
True or False. | Activated macrophages are among the most important types of APCs that can present antigens to lymphocytes.
True
106
Corresponding names of macrophages according to tissue location
Histiocytes - CT Microglial cells - brain Mesanglial cell - kidneys Kupffer cells - liver
107
Cells with granular cytoplasm and an irregularly shaped, lobed nucleus, derived from myeloid stem cell lineage
Granulocytes
108
Three types of granulocytes
Neutrophils, Eosinophils, Basophils
109
Type of immunity that is present at birth, non-specific, rapid response, lacks memory response and serves as the body’s initial protection
Innate immunity
110
Body’s first line of defense
Physical barriers Chemical barriers Normal microbiota
111
Different physical barriers of the body
``` Skin Mucous membrane Gastrointestinal tract Genitourinary Tract Tears Saliva Mucus-coated hair in the nose ```
112
This physical barrier undergoes periodic shedding of keratin & epidermis to help remove pathogenic microbes.
Skin
113
Helps the skin inhibit microbial growth
Dryness
114
Functions as a waterproofing of proteins to prevent water-soluble substances from entering the skin
Keratin
115
These are secretions of the skin that have acidic pH
Sweat and sebaceous secretions
116
This protects the body from the exterior surface and is lined by epithelial cells which secrete mucus that covers microbes to be eliminated
Mucous membrane
117
Act as filter found in the respiratory tract
Ciliated cells of the respiratory tract
118
Protective mechanisms of the GIT
Peristalsis, defecation and vomiting that get rid of the microbes
119
Main protective characteristic of the genitourinary tract
Length of the urethra
120
Washes away microbes in the eye surface
Tears
121
It prevents colonization of microbes by diluting its number and washing them from the surface of the teeth and mucous membrane of the mouth
Saliva
122
Protective contents of saliva
lysozyme, urea, uric acid low pH that inhibits the growth of microbes IgA that prevents attachment of microbes
123
Filter air and help trap microorganisms, dust and pollutants
Mucus-coated hair in the nose
124
Chemical barriers in the body
``` Sebum Perspiration Lysozyme Saliva Gastric juices Vaginal secretions Urine Genetic components ```
125
Oily substance that acts as protective covering of the skin produced by sebaceous glands (holocrine)
Sebum
126
Contains unsaturated fatty acids that inhibit bacterial and fungal growth
Sebum
127
Flushes microorganisms from the skin surface
Perspiration
128
Contained in nasal secretions, saliva, tears | Breakdown cell walls of bacteria
Lysozyme
129
Protective mechanism of gastric juices
High acidity destroys microbes
130
True or False. Some microorganisms like H. pylori are able to survive in the stomach by producing urease which neutralizes the stomach acid.
True
131
Vaginal secretion which is acted upon by Lactobacillus, making the area acidic to ward off other pathogenic organisms
Lactogen
132
With acidic pH due to uric acid and hippuric acid that inhibits pH sensitive microbes
Urine
133
Genetical immunity | High pathological specificity
Genetic components
134
Normal microbiota prevents pathogenic organisms from colonizing the host by
Competing for nutrients Producing substances harmful to pathogens Bacteriocins Altering conditions that will affect the survival of the pathogen
135
Considered as ribosomally synthesized antibacterial peptides or proteins that either kill or inhibit the growth of closely related bacteria
Bacteriocins
136
More internalized system of protective cells and fluids that includes inflammation and phagocytosis
Second line of defense
137
Acts rapidly both in the local and systemic levels once the first line of defense is breached
Second line of defense
138
Components of the second line of defense
Cellular defenses | Molecular defenses
139
Use special-purpose cells found in the blood and other tissues of the body All are derived from pluripotent stem cells (granulocytes and agranulocytes)
Cellular defense
140
cells that engulf invading microorganisms (e.g. neutrophils and macrophages)
Phagocytes
141
Receptors used by the cells to regonize pathogens
Pattern recognition receptors (PRRs)
142
These are present in the cell membrane of phagocytic cells such as macrophages and dendritic cells
PRRs
143
Recognize Pathogen Associated Molecular Patterns (PAMPs)
PRRs
144
Structural features which are expressed by microbes (lipopolysaccharide, peptidoglycans, proteins, sugars)
PAMPs
145
A kind of PRR that is located in the plasma membrane of phagocytic cells
Toll-like receptors
146
Recognize pathogen molecules (LPS, flagellin, peptidoglycan, DNA of bacteria, DNA or RNA of viruses, components of fungi & parasites) and Induce defensive cells to release cytokines
TLRs
147
Mechanism of TLR
A TLR recognizes the lipopolysaccharides on the invading microbes in which it dimerizes with another TLR → sends signal to the nucleus → produces interleukins (IL 1 & 8 for inflammation; IL 6 & 12 to promotes specific activities of B & T cells)
148
Local defensive response to tissue damage from microbial infection Mobilizes & attracts immune components to the site of injury
Inflammation
149
Localizes an infection → Prevents spread of microbial invaders, Neutralizes any toxins being produced at the site Aids in the repair of damaged tissues
Inflammation
150
Cardinal signs of inflammation
Rubor (redness), Calor (heat) Tumor (swelling), Dolor (pain) Functio laesa (loss of function)
151
More than 2 weeks of inflammation If neutrophils fail to remove the offending agent, macrophages and lymphocytes take over and form the granuloma to contain the offending agent
Chronic inflammation
152
Mechanism of inflammation
Injury → vasodilatation of the blood vessels → increased blood flow → increased vascular permeability due to endothelial retraction→ leakage of fluids and neutrophils to extracellular tissues → exudate formation → swelling and edema → macrophages and lymphocytes repair tissue damage → formation of a scar or return to normal state
153
Fever is regulated by the
Hypothalamus
154
Systemic response caused by infection from bacteria & their toxins
Fever
155
``` Increases thermostat (setpoint) to higher levels Our body respond by chills and blood constriction until the setpoint is reached ```
Pyrogens
156
Types of pyrogens
Endogenous | Exogenous
157
Endogenous pyrogens
IL-1, Tumor Necrosis Factor (TNF)
158
Exogenous pyrogens
Bacteria, viruses
159
Stimulates immune reaction through IL-1 Some microorganisms such as viruses are sensitive to heat and are killed when exposed to it Heat can also increase metabolism
Fever
160
Benefits of fever
Inhibit multiplication of temperature sensitive microorganisms Impedes nutrition of bacteria by reducing iron availability Can speed up hematopoiesis, phagocytosis
161
True or False. | Fever is only beneficial up to some point. At 41oC, there could be convulsions.
True
162
Engulfment of the invading microorganisms by macrophages & neutrophils
Phagocytosis
163
Types of Macrophages
Fixed/Resident Macrophages | Wandering Macrophages
164
Types of Fixed/Resident Macrophages
Microglia - brain von Kupffer cells - liver Alveolar macrophages - lungs
165
Type of macrophage that is found in bloodstream and migrate to infected area
Wandering macrophages
166
Survey tissue compartments for microbes, particulate matter and dead cells and extract antigens from foreign matter to be presented to T cells
Phagocytosus
167
True or False. | Phagocytes recognize the offending agents via receptors such as Toll-like Receptors which bind to microbial antigen.
True
168
Steps in phagocytosis
1. Chemotaxis 2. Attachment 3. Ingestion 4. Digestion 5. Expulsion
169
Step in phagocytosis: | Phagocytes with protein cell-surface receptors move to a site where they are needed; directed migration 7 of 11
Chemotaxis
170
Step in phagocytosis: | Attachment of phagocytes to an object; phagocytes recognize a bacterium & binds to it with the help of an opsonin
Attachment
171
Step in phagocytosis: | Phagocyte extends pseudopods & surround bacterium forming a phagosome
Ingestion
172
Step in phagocytosis: Lysosome fuses with phagosomes forming a phagolysosome; chemicals (lysozyme, lactic acid, nitric oxide & oxidants) from lysosome attack the bacterium
Digestion
173
Step in phagocytosis: | Phagolysosome fuse with the cell membrane & debris for them to be excreted
Expulsion
174
Cellular components that control viral multiplication
Interferons
175
True or False. | Interferons could be not viral specific and species-specific.
True
176
Interferon that can affect different kind of viruses
Not viral specific
177
Interferon that can affect only viruses that infects a certain species (E.g. humans)
Species-specific
178
Produced by viral infected host cell in response to viruses, RNA, immune products, and antigens
Interferons
179
Interfere with viral multiplication via viral protein synthesis, degradation of viral RNA and prevention of the translation of viral proteins
Interferons
180
React with plasma or nuclear membrane receptors inducing uninfected cell to manufacture mRNA for synthesis of Antiviral Proteins (AVPs)
Interferon
181
Disrupts various stages of viral multiplication
AVPs
182
Used in therapy of certain VIRAL INFECTIONS and CANCER
Interferons
183
Three types of interferons
INF-α INF-β INF-γ
184
Interferon that is a product of B lymphocytes, monocytes & macrophages and activate Natural Killer cells
INF-α
185
Interferon that is aroduct of fibroblasts and epithelial cells and plays a role in B and T lymphocyte maturation and inflammation
INF-β
186
Interferon that is a product of T lymphocytes and NK cells and nduces neutrophils & macrophages to kill bacteria & tumor cells by producing nitric oxide
INF-γ
187
Type of interferon that inhibits cancer cells
INF-γ
188
True or False. INF-α and INF-β are the only ones involved in viral infections while INF-γ is involved in activating macrophages for phagocytosis of bacteria.
True
189
Mechanism of action of interferons
When viruses bind to host cells, a signal is sent to the nucleus to synthesize interferons. These interferons are secreted in the extracellular space and are taken up by uninfected cells. The uninfected cells then produce anti-viral proteins which will inhibit multiplication by interfering with viral protein synthesis. Hence, viral replication is inhibited. This allows other body defenses to fight the disease effectively.
190
Cell that is responsible for extracellular killings in the second line of defense
NK cells
191
Functions of NK cells
Eliminate irreparably injured & tumor cells Recognize and destroy parasitic cells extracellularly Respond by killing these cells & secreting macrophage-activating cytokine INF-γ Fight viral & other intracellular infections by killing host infected cells Has inhibitory receptor and activating receptor Contain lytic enzymes
192
Mechanism of NK cells
In healthy host cells, there is MHC-1 Complex. The NK cells bind to the host cells in its inhibitory receptor thereby inhibiting the activating receptor. As a consequence, the host cell is unaffected. In viral infected cells, MHC is lost. Hence, they bind to the activating receptor which activates the release of lytic enzymes that kill the virus infected cells
193
Primary component of molecular defenses of the body
Complement System
194
Defensive system of proteins produced by the liver and found circulating in the blood serum
Complement system
195
“Complements” the immune reactions in destroying the offending agents
Complement system
196
Consists of around 26-30 blood proteins that work to destroy bacteria and certain viruses via a “cascade reaction”
Complement system
197
Complement system destroys microbes by
Cytolysis Inflammation Phagocytosis
198
Three complement pathways
Alternative Pathway – Innate Immunity Lectin Pathway – Innate Immunity Classical Pathway – Adaptive Immunity
199
True or False. Second line of defense only involve Alternative and Lectin pathway while Classical pathway complements third line of defense or Adaptive immunity.
True
200
Discovered after the classical pathway | Antibody INDEPENDENT pathway
Alternative pathway
201
First response of innate immunity
Alternative pathway
202
Initiated by the presence of microbes – attacking proteins in blood, lymph and extracellular fluids – that have lipopolysaccharides, endotoxins, and yeast cell wall (zymosan), as well as aggregates of IgA which then starts with the hydrolysis of C3
Alternative pathway
203
Mechanism of Alternative pathway
Begins at C3 which is activated at slow rate by water & plasma enzyme (bypassing C1, C4 and C2 components) → C3 combines with complement proteins: factor B, factor D and factor P on the surface of the microbe → C3 is split to C3a and C3b
204
Complement protein that causes inflammation and triggers degranulation of mast cell
C3a
205
Complement protein that causes opsonization & cytolysis
C3b
206
Enters the terminal complement pathway which leads to the formation of the membrane-attack complex (MAC) that can kill the microbes by making holes (cytolysis)
C3b
207
Acts as an opsonin and facilitate phagocytosis
C3b
208
Participates in the formation of C5a which also causes phagocytosis and inflammation
C3b
209
True or False. | C3b is an opsonin while C5a and C3a are anaphylatoxins.
True
210
Most recently discovered | Antibody INDEPENDENT pathway
Lectin pathway
211
Initiated by binding of complement to Mannose, sugar found on microbial cell wall Activated by lectin produced by the liver due to cytokines released by macrophages after ingesting bacteria, viruses & other foreign materials
Lectin pathway
212
MBL associated serine protease in Lectin pathway
MASP-1 | MASP-2
213
MBL-associated serine protease that is synthesized as a zymogen and is activated when it complexes with the pathogen recognition molecules such as MBL
MASP-1
214
Steps in Lectin pathway
1. Lectin (e.g. mannose-binding lectin/MBL) binds to carbohydrate mannose or similar sugars on bacterial and viral cell walls 2. Activation of C2 and C3 3. C2a and C4b combine and activate C3 (gets hydrolyzed to C3a and C3b)
215
Initiated by binding of complement to antibody
Classical pathway