Immunology
Complement System and Activation
Complement: large group of proteins found in blood & tissue
Complements promote: o
1. Phagocytosis
o 2. Inflammatory Responses
o 3. Cytolytic Attack on pathogen/ pathogen- infected cells
Biochemical Features:
o Synthesized mainly by cells in LIVER (90% produced here)
o Makes up 10% of serum globin
o Sensitive to heat treatment
o Exist in PRO-FORM (inactive)…. Need to be activated for biological activity
o Amounts are stable EXCEPT they are affected by cirrhosis of liver & kidney
damage Pathways of Complement Activation:
1. Alternate Pathway: 1 one activated
st
o Pathogen surface creates local environment conducive to complement
activation 2. Lectin Pathway
o Mannose-binding lectin binds to pathogen surface
3. Classical Pathway (last to act, but first two pathways derive from this pathway)
o C- reactive protein or antibody binds to specific antigen on pathogen surface
***Each pathway undergoes “Recognition-Activation-Destruction” ***
Complement Components:
Consist of C1 C9
Key Points:
o In innate immunity, C- reactive protein (C1q) is initiator of class pathway
oC-reactive protein is an ACUTE PHASE PROTEIN, not a complement
component 1 Step: C1 binds to C-reactive protein on pathogen surface
st
o This forms a QRS complex (Q= tubule structure, R/S = enzymes)
o***IgG & IgM can initiate classical pathway (belonging to adaptive immunity)*** 2nd
Step: As soon as complex forms, C4 interacts w/ QRS & is CLEAVED into…
oC4a: inflammatory mediator
o C4b: this binds covalently to microbial surface
3rd Step: C2 binds to C1 QRS Complex and C2 is CLEAVED into...
oC2a: this binds to surface of C4b = CLASSICAL C3 CONVERTASE, C4b2a
o C2b
4th Step: C3 binds to C4b2a & is cleaved into…
o C3a: inflammatory mediator
o C3b: this binds to C4b2a C4b2a3b
5th Step: C5 binds to C4b2a3b to become CLASSICAL C5 CONVERTASE (C4b2a3b)
6th Step: C5 Convertase cleaves into…
o C5a: inflammatory mediator
o C5b
7th Step: C5b goes through 4 complements (C6-C9) form membrane attacking unit to destroy
pathogen membrane
Mannose Binding Lectin (MBL): plasma protein produced by liver upon acute phase reaction
They are proteins that recognize pathogen carbohydrates which belongs to PRR
(pattern recognition receptor) of innate immunity
o Bind specifically to bacterial mannose b/c of defined structure & special difference
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Uses MASP-2 & MASP-1 (basically looks like C1 QRS complex) to activate C4 & C2 to
form Classical C3 Convertase (C4b2a)
MBL Binding also initiates macrophage phagocytosis (act as )OPSONIN
o Complement fragments that coat bacteria & facilitate cell phagocytosis = opsonin
Alternative Activation Pathway: immediately activated when pathogen enters body
Key Point: Pathogen surface creates local environment conductive to complement activation
o Key Step: DIRECT ACTIVATION OF C3 (no c1 c4
c2) C3 is cleaved into…
C3a: recruits phagocytosis (inflammatory mediator)
C3b: tags bacterium for destruction
oFormation of Alternative C3 Convertase: C3bBb (Not C4b2a)
Formation of Alternative C5 Convertase: C5b Bb (Not C4b2a3b)2
Once found, it follows classical pathway of binding w/ C6-C9
MORE STUFF TO THIS, GOODNIGHT
Lecture 2: Inflammatory Cytokines & Signaling Mechanisms
Cytokine: cell-produced peptides & proteins that mediate inflammatory
effects Monokine: cytokines produced by monocytes
Lymphokine: cytokines produced by lymphocytes
Interleukin: cytokines produced by leukocytes & acted on leukocytes
Most are simple polypeptides or glycoproteins
Production is regulated by inducing stimuli
o Under normal conditions, body does NOT produce cytokines
Production is short and very controlled
Cytokines activated by individualized cytokine receptors. Cytokine action:
oAutocrine: acts on itself
oParacrine: cell produced cytokine
oEndocrine: once produced, released into blood stream & goes to brain &
stimulates cytokines
Cytokine induces production of additional cytokines = cytokine cascade
NFkappaB is initially in cytoplasm; once activated, it is free to move into nucleus & acts
as transcription factor to initiated giving expression to cytokine
Proteins form complex that regulates procaspase complex to form active procaspase 1
o This does something & leads outside of cytoplasm
Biological Effects of Inflammatory Cytokines during Pathogen Infection:
IL-1Beta/ TNF- alpha: increase blood vessel permeability that allows effector cells to
enter infected tissue
IL-6: acts on fat muscle (make heat & raise temperature in infected tissue
CXCL8: attract neutrophils from blood & guide them to infected tissue
IL-12: produced by macrophage that activate NK Cells
***Every outcome is cause state of inflammation @ infection site***
Inflammatory Activites of Cytokines in Diff. Organs/Tissues:
IL-1/IL-6/TNF-Alpha:
o Liver: acute phase proteins (produces c-reactive protein, mannose binding lectin)
This leads to activation of complement opsonization
o Bone Marrow/ Endothelium: neutrophil mobilization (Bacteria not viral)
Leads to phagocytosis
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o Hypothalamus: increased body temp.
Leads to decreased viral & bacterial replication
Fever = caused by increase # of cytokines (GOOD to an extent ) o
Cytokines are killing pathogens (decreasing replication)
o Fat/ Muscle: protein & energy mobilization to increase body temp.
Leads to decreased viral & bacterial replication
Increased fever, fat is burned & you become skinny
Pathological Effect of TNF- alpha: MOST important inflammatory
factor Local infection: helps control infection (GOOD)
o Macrophages activated to secrete TNF-alpha in the tissue
o Increased release of plasma proteins into tissue & phagocytes
o Phagocytosis of bacteria/ plasma & cells drain to local lymph node
***goes to specific tissue***
Systemic Infection: (BAD)
o Macrophages activated in liver & spleen & secrete TNF-alpha into BLOODSTREAM
o Systemic edema causes decreased blood pressure (organs don’t have sufficient oxygen &
start dying)
o Ex) sepsis: infection of blood stream
Severe infection bacteria replicate in blood stream(sepsis) systemic TNF-alpha
Acute Phase Proteins: class of proteins whose plasma concentrations increase or decrease in response
to inflammation
This response is called : ability of liver to produce acute phase Acute- Phase Response
proteins which include c-reactive protein, & mannose binding lectin
TNF & IL-1: activate vascular endothelium & increase vascular permeability
IL-12: enhance NK cell cytotoxicity
IL-1, IL-6 & TNF- Alpha: induce inflammatory responses & cause tissue injury
IL-8 & MCP1: induce migration of leukocytes into inflammatory sites
IL-10: down- regulate inflammatory reactions
IL-1 Receptor
Class 1 Cytokine: IL-6, IL-4, IL-2
Class 2 Cytokine: IFN-alpha, beta, &
gamma TNF- receptor family
Chemokine Receptor Family
Eventually activates NFkappaB produce cytokines
Cytokine IL-6 Receptor: activation through JAK/STAT pathway
Cytokine receptor subunits & JAKS are all separate
Cytokine receptor subunits bind JAKs (Janus Kinases)
Cytokine binding assembles receptor, which is phosphorylated
STATs bind to phosphorylated receptor & are then phosphorylated o
STATS: Signal Transducers & Activators of Transcription
Phosphorylated STAT dimers go to nucleus & initiate gene expression
TNF-Alpha Receptor: mediates signaling cascade leading to cytokine production & other activities
This receptor has a DAS domain eventually leads to activating NFkappaB cytokine prod.
Interferon: first line of Defense against viral infection
Natural cell signaling proteins (INDICATOR OF VIRAL
INFECTION) Two Types of Interferons:
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o Type 1: IFN- alpha & beta
Major Functions:
INDUCE RESISTANCE to viral replication in all cells
INCREASE EXPRESSION of ligands for receptors on NK
cells ACTIVATE NK cells to kill virus infected cells
o Type 2: IFN- gamma
Interferon Response: cells gaining anti-viral status
o Begins building status when IFN beta from infected cell binds itself to type 1 interferon
receptor and gives it immunity
Recognizing Virus Infection:
Viral replication in cytoplasm produces uncapped RNA
RLR (RIG1 Like Receptor) binds to viral RNA and induces dimerization
Dimerization initiates signaling pathways that activate IRF3 & NFkappaB o
IRF3: causes synthesis & secretion of type 1 interferons
o NFkappaB: causes synthesis & secretion of inflammatory cytokines
Chemokines: family of chemotactic cytokines
Major function: induce & direct chemotaxis (moving into a particular
place) Proteins classified as chemokines according to:
o Shared structural characteristics (small size)
o Presence of 4 cysteine residues
Receptors are G-protein coupled receptor w/ 7 trans- membrane domains known as
chemokine receptors
o GOES THROUGH MEMBRANE 7 TIMES!!!
***Mvmt. Of immune cells (neutrophils, macrophages.) to inflamm. site is mediated by chemokine***
Chemokine Interleukin IL-8: interacts w/ G protein coupled receptors CXCR1 & CXCR2
Primary Function: induction of chemotaxis in its target cells
o Ex) neutrophils to infiltrate into local inflammatory tissues
Chemokine Receptor Activation:
Chemokine, chemokine receptor & membrane assoc. G protein form a
complex GTP replaces GDP & activates G protein
Complex dissociates to give 2 parts of G protein that initate:
o Pathways of signal transduction
o Cell movement (like moving neutrophils from blood stream to tissue
***GTP, GDP, ATP produce energy needed to move molecules***
Lecture 3: Inflammatory Response in Innate Immunity & Its Regulation
Objectives:
Understand concept of inflammation & 5 cardinal prop. of inflammation
Understand cellular mechanisms by which inflammation is induced
Understand how neutrophils are attracted into inflammatory sites (adhesion & extravasation)
Describe major inflammatory mediators the increase vascular permeability
Understand protective & pathogenic roles of TNF- Alpha
Understand significance of acute phase response & acute phase
proteins Understand mechanism underlying NK cell cytotoxicity
Three Major Stages of Innate Immune
Response: Pathogen Invades
Innate responds to pathogen
Creates inflammation & pathogen is eliminated
Basic Features of Inflammation: body’s protective response to invading pathogens
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Inflammation can be caused by BOTH pathogen or physical causes (car accident,
acid, autoimmune diseases)
Two Types:
o Acute: scratch, cut
o Chronic: liver disease- tissues have constant battle of
inflammation Triggers increases in:
o Local blood supply
o Capillary permeability
o Leukocyte migration & blood clotting
Mechanisms Pathogens use to Damage Tissue:
Exotoxins released
Endotoxins released
Direct cytopathic effect
Inflammatory Response after Infection:
Surface wound introduces bacteria activating resident effector cells to secrete cytokines o
Macrophages are first cells to sense bacteria invasion
Armed w/ diff. types of receptors (ex- toll like receptors)
Interaction w/ bacteria initiates two major functions:
Phagocytosis
Produce inflammatory cytokines (interferons)
o Allows permeability to increased & blood cells leak into place
where bacteria are inflamed tissues (inflammation)
Vasodilation & increased vascular permeability allow fluid, protein & inflammatory cells to
leave blood & enter tissue
Infected tissue becomes inflamed, causing redness, heat, swelling, & pain
Heat: blood supplies this
o Cytokines acting on fat cells to metabolize
Redness: b/c of dilation, skin becomes thinner which is why it is red b/c of RBC
Swelling: permeability increase, large amount of fluid/ protein leaks swelling
o Ex) soft tissue- severe swelling
Pain: due to local inflammation- macrophages produce soo many signals to bring molecules
to site of pathogen
o Ex) kids cry first
Loss of Function: depends on location of inflammation
o If inflammation is in liver/ heart/ brain, function may or may not be permanently affected
Recognition & Response of Tissue Macrophages:
Binding of bacteria to phagocytic receptors on macrophages induces their engulfment
& degradation
o Phagocytosis (form phagosome --> phagolysosome --> bacteria destroyed)
Binding of bacterial components to signaling receptors on macrophages induces synthesis
of inflammatory cytokines
o Ex) TLR4: gram (-) get into body, cell wall has LPS- interacts w/ CD14 forming complex,
complex reacts with TLR4, TLR4 have intercellular signals that activate
NFkappaB & becomes free protein moving from cytoplasm to nucleus which
allows transcription to occur
Three Mechanisms of Cytokines:
Autocrine: proteins that act on the SAME cell that produced
THEM Restricted to working w/n cytoplasm of cello
Paracrine: proteins that act on the NEIGHBORING cell
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o Restricted to working w/n cytoplasm of cell
Endocrine: proteins that can move w/n body of organism
o Ex) go through blood stream and go to brain
Effects of Inflammatory Cytokines: IL-1/IL-6/ TNF-alpha
Activation of Complement Opsonization: produced in liver
o Ex) acute phase proteins (C-reactive protein, mannose binding lectin)
Phagocytosis: produced in bone marrow endothelium
o Neutrophil mobilization
Decreased Viral & Bacterial Replication:
o Produced in hypothalamus: increased body temperature
o Produced in fat/ muscle: protein & energy mobilization to generate increased body temp.
Regulation of Inflammatory Reactions & Pathogenesis: macrophages & inflammatory cytokines do this
Local Infection:
o Macrophages activated to secrete TNF-Alpha in tissue
IMPORTANT CYTOKINE: TNNF-Alpha
Produced locally: regulates inflammatory interactions & controls
bacterial infection & heals tissue
If goes to whole body, blood stream has soo mcuh TNF alpha, it will
act on whole body causing DICs, and leads to organ failure due to
insufficient blood supply & you die
o Increased release of plasma proteins into tissue
o Increased Vascular Permeability:
o Increased phagocyte & lymphocyte migration into tissues
o Increased platelet adhesion to blood vessel wall
o Phagocytosis of bacteria local vessel occlusion containment of infection
o Antigens drain or are carried to local lymph node (YOU
SURVIVE) Systemic Infection:
o Macrophages activated in liver & spleen secrete TNF-Alpha into bloodstream
o Systemic edema causes decreased blood volume, hypoproteinemia, &
neutropenia, followed by neutrophilia
Decreased blood volume causes collapse of
vessels Can’t get inside infected blood vessel
o Disseminated intravascular coagulation leads to wasting & multiple organ
failure: SEPTIC SHOCK (YOU DIE)
Generation of Inflammatory Peptides: C3a, C4a, C5a
Three Types of Complement Pathways:
o 1. Alternative Pathway: activated first
Pathogen surface creates local environment conductive to complement act.
Direct activation of C3 Alt. C3 Convertase (C3BbB) Alt. C5 Convertase
(C3b Bb)2
Eventually forms membrane attacking unit that damages pathogen membrane
Only forms TWO inflammatory mediators: C3a, C5a
o 2. Lectin Pathway: mannose binding lectin recognizes pathogen mannose
Macrophage has to produce cytokine then go to blood stream liver then will
activate acute phase protein (MBL) (takes several days to kick in)
Bacteria surface must have mannose (similar to C1 QRS complex once formed)
Eventually forms membrane attacking unit that damages pathogen membrane
Forms THREE inflammatory mediators: C4a, C3a, C5a
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o 3. Classical Pathway: last to activate
C-reactive protein (acute phase response) binds to C1 to form complex
Can be activated by antibodies (IgG, IgM) – innate immune response
Bind to C4 C2 to produce C3 Convertase (C4b2a) C3a binds to produce C5
Convertase (C4b2a3b) C5-9 react to form membrane attacking complex
Forms THREE inflammatory mediators: C4a, C3a, C5a
Once Complement is Activated:
o Recruitment of inflammatory cell s
o Opsonization of pathogens, facilitating uptake & killing by phagocytes
o Perforation of pathogen cell membranes
***Opsonin: macrophage mark bacteria as foreign substance to be destroyed***
Anaphylatoxins: fragments of complement system (C3a, C4a, C5a) that induce allergy like symptoms
Increase vascular permeability (leaking blood volumes, mucosal surface swelling)
o 1. Increased permeability allows increased fluid leakage from blood vessels &
extravasation of complement & other plasma proteins @ site of infection
o 2. Migration of monocytes & neutrophils from blood into tissue is increased.
Microbicidal activity of macrophages & neutrophils is also increased
Release of Neutrophils into Bld Stream: come from bone marrow to respond to BACTERIAL infections
Neutrophils travel to & enter infected tissue o
Here, they engulf & kill bacteria
o Neutrophils die in tissue & engulfed & degraded by macrophages
IL-1, IL-6 & TNF-Alpha are MAJOR effector molecules CAUSING this event
Lymphocytes: increase when responding to VIRAL infections
Eosinophils: increase when responding to parasite Neutrophil
Infiltration into Inflammatory Site Mechanism:
Under normal conditions: neutrophils are “rolling” along vascular endothelial
surface S-Le & selectin naturally interact w/ each other
ox
Interaction isn’t forceful (affinity low)
Selectin- mediated adhesion is weak
Interact w/ one another, selectin releases neutrophil & continues
rolling cell
Under Inflammation: LFA-1 is highly expressed by neutrophils
o Endothelial cells express LFA-1 receptor ICAM-1, which create a tight interaction
& slows neutrophil rolling
Once interact, form tight reaction, neutrophil cant roll, cells stuck
o In presence of CXCL8 (chemokine) from the macrophages, form gradient that allows
neutrophils pass through the space b/t endothelial cells & migrate into inflammatory
site Acute Phase Response: occurs in the liver
Only occurs when inflammation causes lots of cytokines in blood stream (fever,
increased neutrophils, production of ATP)
This then leads to production of acute phase proteins (c-reactive protein or MBL)
o C-reactive protein binds phosphocholine on bacterial surfaces, acting as an opsonin &
as a complement activator
o MBL binds to carbohydrates on bacterial surfaces, acting as an opsonin &
complement activator
Play major roles in phagocytosis, opsonin & complement
activator Macrophage Phagocytosis:
When bacteria inside neutrophil or macrophages:
o They are killed inside cytoplasm (most toxic chemicals that kill pathogen are
SUPEROXIDE ANION & HYDROGEN PEROXIDE)
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Macrophage Phagocytosis can be initiated by ANTIBODIES (IgG)
o Antibody binds to bacteria antibody coated bacteria bind to FC receptor on
macrophages active phagocytosis formation of phagolysosome
Respiratory Burst in Neutrophils & Macrophages:
There are several enzymes here:
o NADPH Oxidase, Superoxide dismutase, Peroxidase
enzymes Interferon: two types
Type 1: produced by almost any type of cells
Type 2: produced by NK cells & acting on macrophages
Interferon Response: NK cells are activated by interferon to serve as early defense against viral infection
Occurs in 3 Major Ways:
o Induce resistance to viral replication in all cells
o Increase expression of ligands for receptors on NK cells
o Activate NK cells to kill virus infected cells
Antibody-Dependent Cell- Mediated Cytotoxicity (ADCC): belongs to ADAPTIVE immunity
Effector Cells: NK Cells
o Kill virally infected cells
Targeting molecule: antigen specific IgG antibody
o Antibody binds to pathogen target on cell
Required Receptor: Classification of Differentiation (CD16-IgG) antibody interaction
o CD16 interacts w/ antibody & forms bridge that eventually releases poisons to kill
cell Killing Substance: release of perforin
Mechanism: create a pore in target cells
***LOOK AT LAST 3 SLIDES IM DONE GOODNIGHT***
Lecture 4: Immunogen, Antigen & Antibody
Objective:
There’s a sh*t ton of objectives, just know & understand everything
Antigen- Induced Immune Responses: this is how cells begin to interact w/
antigen T Helper cell notifies B cells & Killer T Cells & Macrophages
o T Killer: t- cell mediated immune response
o Macrophage: regulation of innate immunity
o B Cell: mediated humoral immune response (antibodies)
Antigen: any molecule recognized by specific antibody, B cell receptor or can be bound by an
MHC molecule & presented to a T cell receptor
Basically, anything foreign to the body that INTERACTS w/
antibody Antigen can have either:
o Antigenicity: ability of antigen to interact w/ antibody
o Immunogenicity
IMPORTANT: all antigens have potential to be bound by specific antibodies, but some
antigens (HAPTEN- incomplete antigen) need to be attached to a specific substance to gain its
full immunogenicity
o Happen Conjugated w/ Carrier will produce 3 sets of anitbodies:
Specific to carrier protein (Ex- Albumin- will induce immune
response) Specific to Hapten Molecule
Specific to both hapten & carrier
o Clinical Significant: antibodies against hapten often mediate allergic reactions like
hypersensitivity reaction to penicillin (sometimes fatal)
Immunogen: any antigen capable of INDUCING humoral and/or cell- mediated immune response
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Immunogenicity: ability of immunogen to induce an immune response
ALL IMMUNOGENS ARE ANTIGENS, but NOT ALL ANTIGENS ARE IMMUNOGENS
Antigen Epitope: small portion of antigenic molecule that is bound by an antibody or gives rise to
MHC binding peptide that is recognized by a T cell receptor
AKA Antigenic determinant
They are exposed on molecule’s surface & bound by an antibody
oOne antibody only recognizes & binds to one epitope on
antigen : general name for B cell produced antibodiesImmunoglobulin
Proteins produced by B cell
All ANTIBODIES ARE IMMUNOGLOBULINS, but NOT ALL IMMUNOGLOBULINS
ARE ANITBODIES
Ex) Horse Injected w/ snake venom, serum extracted which contains variety of antibodies and
is then injected to us upon snake bite
Antibody Cross- Reactivity: one antibody recognizing one antigenic determinant can interact w/
another antigenic determinant
In other words, binding of an antibody w/ closely related molecules (1:1
ratio) : secreted from of immunoglobulin produced by a B cellAntibody
Synthesized & released by plasma cells that differentiated from B cells
Immunization: DELIBERATE induction of an adaptive immune response
Usually by injecting an immunogen
Can produce antibody and/ or effect T cell activity OR
Interact w/ these antigens
Viral Proteins: STRONGEST
Bacterial Antigens
Carbohydrates Antigens
Lipid Antigens
Most antigens have this, but not all
Having Immunoreactivity: capable of BINDING w/ antibody, B cell antigen & MHC molecules
Almost all antigens have this
Having Defined Chemical Structures: unique biological substances or chemicals on an antigen
Includes proteins, peptides, carbohydrates, lipid, etc.
Size of Antigen: variable dependent on molecules
Large antigens = usually stronger = larger
immunogenicity Types of Antigens:
Xenoantigen: my cells injected into a mouse; my cells are xeno to the mouse (diff. species)
Alloantigen: antigen in human species
Autoantigen: usually a normal protein or complex of proteins that is recognized by
immune system of patients suffering from a specific autoimmune disease
o Ex) some component of eye when damaged leaks into tissues b/c immune cells are sensitive
to eye component, they begin attacking it believing it is an antigen
Heterophile antigen: certain antigens of similar nature, if not identical, present in different tissues
in different biological species, classes or kingdoms
From simple shape to complex structure
Detailed molecular structure (Ex- H-Phobic or H-Philic)
Antigen Heterogeneity: one virus can express different types of proteins on its surface
Variable Antigenicity: different levels of inducing adaptive response
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Some proteins are weak & others strong
Proteins ALONE are sufficient to elicit immune response (T & B
cells) Usually w/ help from adjuvantso
Antigen Presenting Cells (APC like dendritic cells) & T cells are required to help B
cells produce specific antibodies
Presentation of antigens by ACP cells to T cells is determined by T cells that recognized antigens as
peptide fragments bound to major histocompatibility complex (MHC) molecules
Primary Immunization: aka priming
o Established immunological memory
o Initial immunization isn’t a strong immune response
o Subsequent immunizations lead to STRONGER immune responses w/ high specificity
due to immunological memory
Antibody: immunoglobulin secreted from B cells
Immunoglobulin on cell surface: known as B cell surface antigen receptor
o There are other immunoglobulins that are secreted but are not antibodies b/c they do
NT bind to antigen
If on surface of cell = B cell receptor
If secrete in blood plasma & body fluid = real antibody
Types of Antibody:
IgG: MOST IMPORTANT & main type of antibody found in blood
o By binding to antigens from pathogens, IgG protects body from infection
o Cleavage of IgG by a protease splits
into: Fab
Fc (constant variable)
NK cells causing ADDC b/c Fc interacts w/ CD14
IgM: short lived antibody, but the LARGEST antibody
o1st antibody to appear in response to initial exposure to an antigen
IgA: main immunoglobulin found in mucous secretions & mucosal
surface IgE: provide immunity against parasites
oCauses allergic disease but plays pivotal role in response to
allergens : don’t know what the heck this does, just know it existsIgD
Consists of a light chain & a heavy chain
o Light on the outside
o Heavy chain on inside and the trunk
Consists of a variable region or a constant region
o AA sequence varies among all antibodies: variable region
o AA sequence is identical: constant
Consists of a hinge region: allows movement (disulfide bonds)
o Allows:
Wave movement
Rotation
Wag
Bending
4 Subclasses of IgG: they all diff by structure of the hinge
IgG1: one bracket hinge
IgG2: two bracket hinges
o Mother can’t pass placenta to
baby IgG3: LONGEST hinge
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Immunology
Exam 2
IgG4: one bracket hinge
o Involved in neutralization pathogens (but binding affinity is relatively
low) Classical Method for Generating Monoclonal Antibody:
Isolate immune cells from mouse to form antibody forming cells
Fuse w/ myeloma cells hybridomas which are screened for production of desired antibody
Antibody producing hybridomas cloned clonal expansion monoclonal antibodies (purified)
Injection Techniques & Concerns (Lab)
Objectives:
Compare & contrast intramuscular, subcutaneous, & intradermal administration techniques
& materials
o What to use, different uses
Evaluate results of TB test
Discuss proper Technique for vaccine reconstitution
Rights of Administration:
Right Patient
Right vaccine (& diluent)
Right Time (age, interval,
expiration) Right Dose
Right route (Needle
technique) Right site
Right documentation
Vaccine Inspection:
o Visual appearance
o Storage temperature
o Expiration data
Have all supplies ready before starting the process
o Hand sanitizer, gloves, cotton balls, band aids, alcohol swabs, correct needles, syringe sizes,
vaccine (diluent if needed), sharps container, trashcan, biohazard bag/ container
Create a ROUTINE
o Keeps you from forgetting a step
o Streamlines the process & makes you more efficient
Reconstitution or agitate, if need (ex- roll the vial in b/t
palms) Vaccine batch prep.
o CDC does NOT encourage this practice
o Label: name, lot #, date/time of fill, expiration
NEVER combine vaccines in a single syringe
o Diff. vaccines
o Partial of same vaccine from diff. vials
Intramuscular Injection Sites:
Deltoid Muscle (Upper Arm Muscle)
Diptheria- tetanus & Diphtheria- tetanus- pertussis
Haemophilus influenzae type b
Hep A & B
Human Papillomavirus
Inactivated influenza *
Meningococcal Conjugate
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Pneumococcal Conjugate
Inactivated Polio *
Pneumococcal Polysaccharide *
* Live vaccines are given SQ***
Pediatric IM Injection:
Deltoid muscle
Needle length: 5/8 to 1”
o Use 5/8” until child is in pre-teens
Needle Gauge: 22-25 gauge
Deltoid Muscle
Needle Length: 5/8 to 1”
o Use 5/8” for little old ladies
o Standard needle is 1 inch
Needle Gauge: 22- 25 gauge
Visually find the muscle o
“C” Method
o Finger Method:
3 finger width (HUGE VARIATION)
Avoid areas w/ sores, rashes, scars, or tattoos
Only inject at a 90 DEGREE angle
o Bury needle in arm
o Aim for the middle
***REVIEW IM INJECTION STEPS***
Subcutaneous Injection Sites:
Triceps- fatty area on back of
arm Subcutaneous Vaccines:
Inactivated polio*
Pneumococcal Polysaccharide*
Measles-Mumps-Rubella
Varicella
Meningococcal
Polysaccharide Zoster
Fatty Tissue
Needle Length: 5/8” (everyone)
Needle Gauge: 23-25 gauge
Must be given at a 45 degree angel
o Make sure to hit subcutaneous & NOT muscle
***REVIEW SQ INJECTION
STEPS*** IM/ SQ Post Injection Counseling:
Reassure patient
Ask patient to wait for 10-15mins for evaluation of adverse events
Reiterate common side effects (injection site pain or redness) & side effects that require
medical attention (anaphylaxis)
Tuberculin purified protein derivative (PPD)
Inject at a slight angle, stay in skin longer
PPD Needle & Syringe:
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Needle & syringe packaged together
o Safety device
Needle Length: ¼ to ½”
Needle Gauge: 26 to 29
gauge Short bevel
o Not entire needle in skin
o Bevel needs to be UP
PPD Injection Location:
Palm-side-up surface of forearm 2-
4” antecubital space (elbow)
avoid areas w/ veins, sores, rashes, scars, tattoos, inside hair line if possible
***REVIEW PPD INJECTION STEPS***
PPD Patient Counseling:
Must read induration in 48 to 72 hours
Mild itching, swelling, irritation normal
o Do not scratch
Avoid creams, lotions on site No
band aids or tight coverings
Reading PPD:
Need good lighting
Measure induration:
o Hard,dense, raised formation
o Erythema is NOT measured (no redness
measured) Find margins of induration
o Measure WIDEST edges of induration
ACROSS the arm, not up and down
o Record in millimeters
Positive Result: depends on induration measurement & risk factors for exposure to TB
>/ 5mm (high risk): peoples who immune system isn’t
working o HIV infected person
o Immunosuppressed people
>/ 10mm (medium risk): pretty much everyone is here
o Recent immigrants (<5yrs)
o IVDA (IV Drug Abusers)
o Residents of Employees of high risk settings (jail, nursing
homes) TB spreads fast here
Hospitals, healthcare facilities, homeless shelters, residential facilities of
HIV/ AIDS patients
>/ 15mm (low risk)
o Everyone else, regardless of risk factors
Reconstitution: mix powder (vaccine) w/ diluent (Liquid)
Required for lyophilized (freeze-dried)
vaccines Storage
o Vaccine in freezer (-15 degrees)
o Diluent @ room temperature or refrigerator
ALWAYS:
o Use diluent provided by manufacturer
o Refer to package insert for directions, vaccine appearance, & expiration time
frame Switch needle to avoid potential dull needle for administration
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Will require agitation to dissolve powder & uniform solution/ suspension
Administer ENTIRE contents of liquid
o Will not always be 0.5 mL or 1 mL
Expiration:
o Unmixed = expiration date on vials
o Mixed = manufacture directions
VARIES from immediately 24 hours
Make sure patient has filled out forms, insurance or patient has paid cash before
diluting vaccine
Principles of Vaccination & Screening Patients
Objectives:
Understand the difference b/t passive & active immunity
Describe characteristics of live attenuated, inactivated, & polysaccharide
vaccines Understand basics of vaccination in practice
Discuss screening & its importance in vaccinating patients
Antigen: foreign to the body
Ex) live or inactivated substance capable of producing immune response
Protection produced by own immune
system Lasts many years; often lifetime
Source: body gains exposure from past illness or
vaccine :Passive Immunity
Protection transferred from another person/ animal
o Ex) transplacental- most important source in infancy
If mom doesn’t have immunity to it, she can’t pass on those antibodies
Better protection for measles, rubella, & tetanus
This is temporary protection that wanes w/
time Sources of passive immunity:
o Mother to infant
o Blood products for transfusion
o Immune globulin antibodies (human): basically a immune shot on steroids
(contains LOTs of antibodies from donors)
o Antitoxin (animal)
Live- Attenuated: made in lab
Modifying a disease creating a “wild” virus n
o “wild” organism does NOT cause illness
Attenuated = WEAK
Must replicate in the body to be effective
o Immune response similar to natural infection
Immunity w/ 1 dose typically (not oral ones)
st
o2nd dose provides a very high level of immunity
o Active immunity may not develop
if: Pregnant
Transfusion
***Most live vaccines are VIRAL, two are bacterial (BCG, Oral Typhoid) but not in
U.S.*** Inactivated Vaccines: killed
Bacteria/ vaccine inactivated w/ heat or chemicals
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Only certain components that are meant be included are further purified Can NOT
cause disease & not affected by circulating antibodies
o HOWEVER, it takes two weeks to work
Requires multiple doses & booster doses
Polysaccharide Vaccines: inactivated vaccine that contains subunit of sugar molecules that
antigen displays on bacterial surface
Multiple doses are NOT needed
Cannot be given to children younger than 2 YRS of age
Examples: be careful, forms can be found in both of the below
subunits o Pure Polysaccharide
o Conjugate Polysaccharide
Timinig & Spacing Vaccines:
All vaccines can be adinstered at the same visit (one
exception) Can be an issue if:
o Patient has had blood products
o If a live vaccine has been administered
o If the patient has waited too long between
doses Scenario 1: Blood Products:
Circulating antibodies can interfere w/ vaccine antigen
Blood products have antibodies in them
o Inactivated vaccines are ok
o Live vaccine might not replicate as well
Separate:
o MMR given first – wait 2 wks before antibody
o Antibody given first- wait 3 months
Scenario 2: Same Time Dosing
If patient needs >1 vaccine @ given
appt: o Ok to give multiple
No increase in adverse reactions
Do NOT mix vaccines in same syringe
Scenario 3: 2 weeks ago
If vaccine is LIVE:
o Wait 4 weeks for next If
vaccine was INACTIVATED:
o Give requested vaccine today
Scenario 4: Late Booster
Increasing interval b/t doses of multidose vaccine does NOT diminish
effectiveness Decreasing interval WILL interfere w/ antibody response
o Vaccines should also not be administered to earlier than min. age (insurance
usually) 4 day “grace” period before min. age
LATE BOOSTER GIVE MISSED DOSE NOT
necessary to restart series or add doses
Caused by vaccine
Three Types:
o Local: typical redness, pain, swelling
o System: usually because of live vaccine (feel yucky)
o Allergic: very rare (risk minimized by screening)
Adverse Event: anything that happens after
May or may not be caused because of vaccine
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Screening Patients:
Screen EVERY PT. & EVERY TIME
o Screen for contraindications & precautions
Pt reviews VIS
Consent Form is complete
Allow pt. to ask questions!
Consider vaccine deferral
Consider vaccine referral to physician (or call)
Consider precautions & contraindications
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