immunity

1. 1
UNIT: IV
IMMUNITY
DEFINITIONS:
1) ACTIVE IMMUNITY: specific resistance to
disease acquired by individual as a result of
their own reaction to pathogenic
microorganisms or to the products of such
organisms.
2) ALLERGY: a type of antigen antibody
reaction marked by an exaggerated
physiological response to a substance in
sensitive individuals.
3) ANAPHYLATOXIN: a complement derived
peptide, c5a that causes the release of histamine
from mast cells.
4) ANAPHYLAXIS: hypersensitivity following
the parenteral injection of an antigen.
5) ANTIBODY: serum proteins produced by an
animal in response to the antigen.
6) ANTISERUM: blood serum that contains
antibodies.
7) ANTITOXIN: an antobody capable of uniting
with and neutralizing a specific toxin.
8) AUTOIMMUNE DISEASE: a condition in
which the body develops an immunological
reaction against it on tissues.
9) HUMORAL IMMUNITY: immunity arising
from the formation of specific antobodies that
circulates in blood stream in response to the
introduction of an antigen.
10) HYPERSENSITIVITY: an immune response
that damages the body’s own tissues.
11) IMMUNE SERUM: blood serum that that
contains one or more specific
12) IMMUNITY: a natural or acquired resistance
to a specific disease.
13) IMMMUNIZATION: any process that
develops resistance to a specific disease in a
host.
14) IMMUNOGLOBULIN: any of the serum
proteins such as gamma globulin, which
possess antibody activity.
15) IMMUNOLOGY: the study of immunity to
disease.
16) IMMUNOPROPHYLAXIS: the prevention
of disease by the administration of vaccines or
hyper immune sera.
17) SERODIAGNOSIS: diagnosis by observing
the reaction of blood serum.
18) SEROLOGY: the branch of medical science
which deals with the study of serum.
19) TOXIN: a poisonous substance such as a
bacterial toxin elaborated by an organism.
20) TOXIN- antitoxin: a mixture of toxin and anti-
toxin content slightly more toxin than anti-
toxin.
21) TOXOID: a toxin that has been treated to
destroy its toxic properties without affecting its
antigenic properties.
22) VACCINATION: inoculation with biological
preparation to produce immunity.
23) VACCINES: preparations of live attenuated or
dead organisms which when introduced in to
the body produce artificially active immunity.
IMMUNITY
• The term immunity refers to the resistance
exhibited by the host towards infection caused by
microorganisms and their products (toxins).
• This is based on the property of self and non self
recognition. That means immunity is carried out by
the process of recognition and disposal of non self
or materials that enter the body.
• Immune response is the reaction of the body
against any foreign antigen.
• But protection against infection disease is only a
part of it.
INSIDE:
A. IMMUNITY- DEFINIIONS AND TYPES OF
IMMMUNITY
B. IMMUNIZATION SHEDULE,
IMMUNOPROPHYLAXIS
C. HYPERSENSITIVITY AND
AUTOIMMUNITY
D. PRINCIPLES AND USES OF SEROLOGICAL
TESTS

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DEFINITION OF IMMUNITY
Immunity is defined as the resistance offered by the
host to toxic molecules, microorganisms and
foreign cells.
TYPES OF IMMUNITY
• Immunity against infectious disease is 2 types:
1. Innate or Native immunity
2. Adaptive or Acquired immunity
Immunity against infectious diseases
Innate or Native immunity
a. Non-specific
B. Specific
i. Species immunity
i. Species immunity
ii. Racial immunity
ii. Racial immunity
iii. Individual immunity
iii. Individual immunity
Adaptive or Artificial immunity
a. Active immunity
b. Passive immunity
i. Natural
i. Natural
ii. Artificial
ii. Artificial
Innate or Native immunity
a. Non-specific b. Specific
i. Species immunity i. Species immunity
ii. Racial immunity ii. Racial immunity
iii. Individual
immunity
iii. Individual
immunity
Adaptive or Artificial immunity
a. Active immunity b. Passive immunity
i. Natural i. Natural
ii. Artificial ii. Artificial
INNATE IMMUNITY
• First line of defense against infections
• Not affected by prior contact with infectious
microorganisms or by immunization.
• Specific (resistance to particular pathogen)
• Non-specific (general degree of resistance to
infections)
Species immunity
• Example: Resistance to plant pathogens and large
number of animal pathogens like rinderpest and
distemper.
• Mechanism- unclear but may be due to
physiological and biochemical differences between
the tissues of different host species
• Determines whether or not a pathogen can
multiply in them Total or relative refractoriness to
a pathogen, shown by all members of the species.
Racial immunity
• High degree of resistance of Algerian sheep to
anthrax.
• In USA, people of African origin more
susceptible than Causcasians to tuberculosis

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. • Genetic resistance to Plasmodium falciparum
malaria – some parts of Africa and Mediterranean
coast
• Hereditary abnormality ‘Sickling’ confers
immunity – survival advantage in malarial
environment. Within a species, different races may
show differences in susceptibility to infection.
Genetic in origin, by selection and inbreeding,
races possess high degrees of resistance or
susceptibility to various pathogens.
Individual immunity
• Genetic basis evident from studies on incidence
of infectious disease in twins.
• Ex: Homozygous twins exhibit similar degrees of
resistance or susceptibility to lepromatous leprosy
and tuberculosis.
Mechanisms of innate immunity
a. Epithelial surfaces: -Intact skin and mucosal
membrane – mechanical barrier, bactericidal
activity (due to high salt concentration in drying
sweat, sebaceous secretions and long chain fatty
acids and soaps). -Salmonella kept over glass slide
ans skin at intervals. -Frequent mycotic and
pyogenic infections seen in persons who immerse
their hands in soap water for longer periods. -
Mucosa of nose- Architecture prevents the inhaled
particles entering the passage, also by mucus lining
the epithelium and are swept back to the pharynx
which tend to be swallowed or coughed out.
Mechanisms of innate immunity
a. Epithelial surfaces: (CONTINUED) -Mouth
(saliva); Stomach (gastric digestive juices);
Conjunctiva: flushing action of lacrimal secretion.
-Tears contains lysozyme, an antibacterial agent
(Fleming), also present in all tissue fluids except in
CSF; -Flushing action of urine eliminates bacteria
from urethra. -Spermine and zinc present in sperm
has antibacterial activity. -Acidity of adult vagina
due to glycogen fermentation in epithelial cells by
resident acid uric lactobacilli makes it inhospitable
for many infections
b.Antibacterial substances in the blood &
tissues: - Betalysin (thermos table) – active against
anthrax and related bacilli - Basic polypeptides like
Leukins and Plakins from Leukocytes and Platelets
- Acidic substances like Lactic acid in tissues -
Lactoperoxidase in milk - Interferon (Protection
against viral infections) Mechanisms of innate
immunity - Microbial antagonism: Skin and Mucus
membrane has resident commensal bacterial flora
which prevent colonization by pathogens. Germ
free animal (Gnotobiotic animals are susceptible to
all types of infections)
C. Cellular factors: Phagocytes – Metchnikoff-
Phagocytosis – Microphages (Polymorphonuclear
leukocytes) & Macrophages (Histiocytes-
wandering ameboid cells in the tissues). -
Encapsulated Streptococcus pneumoniae are not
phagocytosed in the presence of opsonins. -
Brucella, Salmonella typhi and Lepra bacilli resist
intracellular digestion and may actively multiply
inside the phagocytic cells. -NK cells activated by
interferons – non-specific defense against viral
infections and tumors
d. Inflammation
e. Fever: Theraputic indication of fever was
instituted in treponema pallidum infection causing
Syphilis.
f. Acute phase proteins: Enhance host resistance,
prevent tissue injury and promote repair of
inflammatory lesions. CRP, alpha-1 acid
glycoprotein, serum amyloid P component,
mannose binding protein, hs-crp etc.
g. Toll-like receptors: Cell associated receptors in
Innate immunity
ADAPTIVE IMMUNITY
• Also known as Acquired immunity
• Antigenic specificity
• Diversity •
Immunological memory
• Self/non-self recognition: Self-tolerance. Failure
of self tolerance results in autoimmunity
Types of Adaptive immunity
• Active immunity
• Passive immunity

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Active immunity:
• Functioning immune system – B lymphocytes –
Antibody production – Production of
immunologically active cells.
• Sets only after latent period, often there is a
negative phase where measurable immunity may
be lower than it was before the antigenic stimulus.
Because antigen binds to specific antibody and
lower its level in circulation.
• Once developed, it is long-lasting, second
immune response is rapid.
• Bothe CMI and humoral immunity developed;
Immunological memory is present.
• Active immunity more effective and confers
protection than passive immunization. Resistance
developed by individual as a result of antigenic
stimulus. Also called adaptive immunity
Natural active immunity
• Clinical or inapparent infection by microbe.
• Patient recovered from attack of Measles
develops natural active immunity.
• Large proportion to poliomyelitis due to
childhood infection.
• Immunity is lifelong as in Chicken pox &
Measles. • Influenza or common cold; short-lived,
can recur.
• Premunition immunity: In Syphilis, re-infection
lasts only as long the original infection remains
active. Once disease is cured patient is prone for
spirochete infection.
• But in Chancroid, caused by Hemophilus
ducreyi, no effective immunity produced, re-
infection common
Artificial active immunity
• Resistance induced by vaccines
• Bacterial vaccines: Live (BCG for TB), Killed
(Cholera vaccine), Subunit (Typhoid Vi antigen),
Bacterial products (Tetanus toxoid).
• Viral vaccines: Live (Oral polio vaccine - Sabin),
Killed (Injectable polio vaccine-Salk), Subunit
(Hepatitis vaccine) Artificial active immunity •
Live vaccines – initiate infection without causing
disease or injury. Immunity lasts for several years,
but booster dose necessary. Can be administered
orally or parenterally.
• Killed vaccines – Less immunogenic than live
vaccines. Protection lasts only for a short period.
Atleast 3 doses required 1. Primary dose, 2. booster
dose. Ideal route: Parenteral. May be given orally,
but not effective.
• Humoral antibody response following parenteral
immunisation can be improved by adding
‘adjuvants’ like Aluminium phosphate.
Passive immunity:
• No active role from host’ immune system. No
need antigenic stimulus. Preformed antibodies are
administered.
• No latent period. Immediately after
administration, renders active protection.
• No negative phase. No secondary IR.
• Immunity is transient, lasting days to weeks, only
till the passively transmitted antibodies are
metabolised and eliminated.
• Factor of Immune elimination limits the
usefulness of repeated passive immunisation.
• Less effective, acts immediately so it provides
‘instant immunity’ Resistance transmitted
passively to a recipient in readymade form.
Types of Passive immunity
• Natural passive immunity
• Artificial passive immunity

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• Combined immunization
Natural passive immunity
• Resistance passively transferred from mother to
baby. • Maternal antibodies are transmitted to baby
by placenta. • Human colostrum- rich in IgA,
resistant to intestinal digestion, gives protection to
the neonates. • Human fetus, by 20th week starts
producing IgM but still inadequate at birth. • By 3
months of age- infant acquires some immunological
independence, though maternal antibodies give
passive protection. • Active immunisation of mothers
during pregnancy can improve the quality of passive
immunity in infants.
Artificial passive immunity
• Resistance transferred to a recipient by
administration of antibodies.
• Hyperimmune serum of humans or animals
• Convalescent sera and pooled human gamma
globulin. • Equine hyperimmune sera such as anti-
tetanic serum (ATS) prepared from
hyperimmunised horses was extensively employed
but now stopped due to hypersensitivity reactions
and immune elimination. Artificial passive
immunity
• Human hyperimmune globulin such as Tetanus
Immune Globulin (TIG) free from those
complications and provides more lasting
protection.
• Animal preparations (antisera) like anti-gas
gangrene, anti-venom & anti-botulinum
preparations are used due to non-availability of
human preparations.
• Convalescent sera (Acute phase serum and serum
obtained from patients recovering from infectious
diseases) contains high level of specific antibody.
• Pooled human gamma globulin (from healthy
adults) contains antibodies against common
pathogens prevalent in the region.
• Convalescent sera and pooled immune globulin is
used for passive immunization against some viral
hepatitis A infections.
• Human gamma globulin is used in treatment of
patients with immunodeficiencies.
• Indications:
• For immediate and temporary protection in a non-
immune host faced with threat of infection.
• To suppress active immunity if it is injurious, for
ex: rh immune globulin during delivery to prevent
IR to Rhesus factor in Rh negative women with Rh
positive babies.
Active immunity Passive immunity
a. Produced actively
by the host’s immune
system
a. Received passively.
No active host
participation
b. Induced by
infection or by
immunogen
b. Readymade
antibody transferred
c. Durable effective
protection
c. Transient, less
effective
d. Immunity effective
only after lag period
d. Immediate
immunity
e. Immunological
memory present
e. No immunological
memory
f. Booster effect on
subsequent dose
f. Subsequent dose less
effective
g. Negative phase may
occur
g. No negative phase
h. Not applicable in
the immunodeficient
h. Applicable in the
immunodeficient
IMMUNOPROPHYLAXIS
Immunoprophylaxis is the prevention of disease
by the administration of vaccines or hyper
immune sera or it may be defined as the

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prevention of disease by the production of active
or passive immunity.
Immunization according to who definition is the
process where by a person is made immune or
resistant to an infectious disease, typically by the
administration of a vaccine.immunization is of
three types:
Protection against infectious diseases by
(immunization) acquired by the individual either
passively or actively:
I- Passive acquired immunity
II- Ii- active acquired immunity
I- PASSIVE ACQUIRED IMMUNITY
Readymade ab transferred to individual giving
rapid protection and short lasting immunity:
A-naturally acquired passive immunity
occurs when antibody are transferred from
mother to fetus (igg ) or in colostrum (ig a).
b- Artificially acquired passive immunity
Short-term immunization by injection of
antibodies, for examples: - injection of
antitoxic serum for treatment of diphtheria or
tetanus. - Injection of gamma globulin that are
not produced by recipient's cells, to
hypogammaglobulin children.
II- ACTIVE ACQUIRED IMMUNITY
Individual actively produces his own
ab. Immunity develop slowly and long
lasting due to development of
immunological memory:
A-natural active acquired immunity the
person becomes immune as a result of
previous exposure to a live pathogen
B-artificially active acquired immunity
a vaccine stimulates a primary response
against the antigen without causing
symptoms of the disease.
TYPES OF IMMUNIZATION
1. Active immunisation
Vaccines are preparation of live attenuated or dead
organisms which when introduced in to the body
produce artificially active immunity.
Types of vaccine
I. Live attenuated vaccines: there are the
suspensions of living organisms with
reduced virulence but are able to produce
antibodies. A single dose include long
lasting immunity and the immunity can be
reinforced by subsequent booster dose.
Example: bcg vaccine, oral typhoid
vaccine, opv, measles vaccine, mumps
vaccine, rubella vaccine, varicella vaccine.
II. Inactivated or killed vaccine: in such
vaccines the organism is killed by heat,
formalin, phenol, alcohol or uv
radiations.usually three dose of vaccines
are given.generally 2nd
dose is given 6th
weeks after first dose and 3rd
dose after 6th
month of 2nd
dose.
Example: pertussis vaccine, plague vaccine,
cholera vaccine, killed polio vaccine, hepatitis a
vaccine
III. Toxoids: toxoids are modified toxins that
have lost toxigenicity but retain
antigenecity.toxoids are usually prepared
by inactivating exotoxins with formalin or
heat.
Examples: diphtheria toxoid vaccine, tetanus
toxoid vaccine.
2. Passive immunization: it involves injection of
exogenous antibody present in human or animal
serum to provide immediate protection to an
infection.the immunity so produced is for a limited
period and short lasting till the antobodies are
eliminated from the body. Three types of
preparations are available for passive
immunizations:
1) Pooled immunoglobulin: it is prepared from
pooled normal human serum containing high
levels of appropriate antobody.human normal
immunoglobulin is used in short term
prophylaxis against hepatitis a and measles in
contacts or travelers who intend to visit
countries where such disease are more
prevalent.
2) Specific immunoglobulin or specific human
immunoglobulin: it is prepared from the serum

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of patients who are recovering from infection
or from person who have been actively
immunized against a specific infection.
Specific immunoglobulin are available against
tetanus as human tetanus
imunoglobulin,hepatitis b as human
immunoglobulin,rabies human rabies
immunoglobulin (hrig)
3) Homologous and hetrologous sera:
antibacterial, antiviral antibodies in human
serum are injected to provide temporary
protection against infection.
2. Combined passive and active
immunization: in some disease, passive
immunization is undertaken in conjution
with inactivated vaccine products in order
to provide both immediate passive
immunity which is tempory and slowly
developing active immunity which lasts for
longer periods of time. Both the
preparations should be injected at different
sites in a body.
VACCINE SERUM
Vaccine is a mixture of
live orr dead germs or
viruses of a particular
disease.
Serum is a clear, hay
colored liquid which is
obtained after the clotting
of blood cells.
Vaccine is injected to
raise resistance of the
body against that
disease
Not applicable with serum
Vaccine generally
contains antigens
Serum contains antibodies
Vaccine is used to fight
against disease
Serum is used in
diagnostic tests and blood
typing
The content of vaccine
is specific
Serum is a mixture of
many different substances
2.
HYPERSENSITIVITY
Hypersensitivity is an exaggerated immune
response that results in tissue damage and is
manifested in the individual on a second or
subsequent contact with an antigen.
Hypersensitivity reactions can be classified as
either immediate or delayed.
There are six types: i.ii.iii.iv.v.vi
IMMEDIATE HS DELAYED HS
Reaction appears
immediately within
minutes and recedes
rapidly usually in one
hour.
Appears slowly within 24-
72 hours and lasts longer
for days
Antibody mediated
reaction
Cell mediated reaction
Passive transfer possible
by serum or their extracts.
Transfer possible only with
lymphoid cells
Desensitization is easy but
short lived
Difficult but long lasting
Wheal and flare with
maximum diameter in 6
hour.
Erythema and induration
with maximum diameter in
24 to 48 hours.
TYPE-I: HYPERSENSITIVITY:
ANAPHYLACTIC REACTION
The term anaphylaxis is used when the
manifestations of allergic reaction are severe.
It is ige mediated hypersensitivity reaction that
occurs quickly when a large shocking dose of
antigen is introduced after one or more small
sensitizing doses.
Features of anaphylaxis:
1. Reaction occurs immediately in few second
to few minutes after administration of
shocking dose.
2. Ige produced has affinity for skin cells and
is probably synthesized in man only.
3. The manifestations occurs due to
constriction of smooth muscle and
increased vascular permeability.
4. Duration is short.
5. It is not a heritable disease.
Manifestation of anaphylaxis:

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Manifestations of anaphylaxis depend on
species of animals, amount of shocking dose,
site of injection and portal of entry of antigen.
The manifestations may be local or systemic.
Localized anaphylaxis: it include cutaneous
and mucosa anaphylaxis.
Systemic anaphylaxis: it is rare in man and
occasionally observed in hypersensitivity
individuals by insect stings, injection of foreign
serum or drugs antibiotics etc...
ATOPY
it is a type i hypersensitivity reaction that occurs
spontaneously in response to substances that are
usually present i our environment in everyday
life.about 1% population is prone to such
environmental antigen such as pollen, animal
dander, wheat husk, certain foods etc. The most
common manifestations are fever and asthma.
Features of Atopy:
Atopy shows familial distribution
Reactions occurs at the site of entry of ag.
Atopy is ige mediated hypersensitivity reaction.
2. TYPE-II: CYTOTOXIC REACTION
It is mediated by antibodies – igg, igm that are
directed towards antigens present on the
surface of cell or other tissue components and
ultimately resulting in damage of cell.
The antibody is produced against an antigen
that can be microbial product absorbed on to a
cell or drug.
Both igg and igm are produced in type ii
reaction.
The ab attaches to ag via fab region followed
by complement fixation via fc region causing
damage to cell as a result of ag-ab reaction.
Examples: isoimmune reactions, autoimmune
reaction, drug reactions etc…
3. TYPE-III: IMMUNE COMPLEX
REACTION
It involves formation of immune complex.
Normally these complexes are phagocytosed
effectively by monocytes and macrophages.
In the presence of excess amounts of some
soluble antigens, the antigen antibody
complexes may not be effectively removed.
And it leads to inflammatory response in the
body.
4. TYPE:IV: DELAYED REACTION
It involves delayed, cell mediated immune
response.
A major factor in the type IV reaction is the
time required for t cells to antigen to migrate
and accumulate near the antigens.
5. TYPE:V:STIMULATORY TYPE
REACTION
It is a modification of type ii hs reaction in which
an interaction of abs with ags occur on surface of
cell that cause proliferation and differentiation of
cell instead of killing.
Such antibodies produced in this reaction are non-
complement fixing and the ag-ab complex
enhances the functional activity of affected cell.
The classical example of this type of
hypersensitivity reaction is graves’ disease in
which thyroid hormone are produced in excess
amount.
6. TYPE-VI: ANTIBODY DEPENDENT
CELL MEDIATED CYTOTOXICITY
ADCC REACTION
It is mediated through natural killer cells.
Target cells coated with low concentration of abs
are killed by NK cells through an extracellular non-
phagocytic mechanism.
AUTOIMMUNITY
AN autoimmune disorder is a condition that occurs
when the immune system mistakenly attacks and
destroys healthy body tissue or any of a large group
of disease characterized by abnormal functioning
of the immune system that causes your immune
system to produce antibodies against your own

9. 9
tissue. There are more than 80 different types of
autoimmune disorders
1. Addison’s disease
2. Celiac disease
3. Dermatomyositis
4. Graves’ disease
5. Chronic thyroiditis
6. Multiple sclerosis
7. Myasthenia gravis
8. Pernicious anemia
9. Reactive arthritis
11. Rheumatoid arthritis
12. Sjögren syndrome
13. Systemic lupus erythematosus
14. Type 1 diabetes.
PRINCIPLES AND USES OF
SEROLOGICAL TESTS
 Serum is the liquid portion of blood that
contains many different components,
especially the immunoglobulins or
antobodies.
 Serology is the study of serum.
 It is the science that studies antigen
antibody or immunological reactions of the
body using a serum specimen.
 Serological reactions are simple, rapid and
specific. The test results are reliable and
responsible.
 Serological tests to detect the antibodies
against the infecting microorganisms
provide a useful means of indirect
diagnosis.
PRINCIPLES OF SERODIAGNOSTIC TESTS
1) PRECIPITATION
When a soluble antigen combines with its
corresponding ab in presence of electrolyte at a
suitable temperature, the ag-tb complex forms an
insoluble precipitate a reaction called precipitation.
2) FLOCCLATION
It is the aggregation of inert particles like latex,
charcoal, and cholesterol emulsion coated with an
antigen as a result of immunological reaction.
This flocculation technique is best applied in vdrl
test for the diagnosis of syphilis.
3) AGGLUTINATION
When an immune complex is formed by cross
linking cells or particles with specific antibodies, it
is called an agglutination reaction.aggllutination
reaction usually forms visible aggregates or
clumps.
Such clumps are called agglutinates which can be
seen through unaided eyes.
Direct agglutination reactions are very useful in the
diagnosis of certain disease.
Example: blood grouping, Widal test.
4) NEUTRALIZATION REACTION
In neutralization toxin produced by the pathogen is
used as the reagent which is neutralized by the
antibody produced by the patient or present in his
serum.
It os applied in the antistreptolysin o test for the
diagnosis of a streptococcus pyogenes infection.
5) COMPLEMENT FIXATION
When complement binds to an antigen antibody
complex it becomes fixed and used up.
A known antigen is mixed with test serum lacking
complement. When immune complexes form
complement is added.
If immune complexes are present they will fix and
consume complement.
Afterwards sensitized indicator cells usually sheep
red blood cells are added to the mixture.
Lysis of the indicator cells occur if immune
complexes do not form.
Absence of Lysis shows that specific antibodies are
present in the test serum
Complement fixation is used for diagnosis of
syphilis.

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6) IMMUNOFLUORESCENE TESTS
These asaays use the same principle as Ela, and like
eia they can be constructed to detect either viral
antibody or antigen in the patient specimen.
However instead of the enzyme aubstratre detector
system of eia fluorescein labelled anti human
antibody is used to detect a positive reaction which
apperas as apple green fluoresecene under a light
microscope.
7) WESTERN LOT OR LINE
IMMUNOASAAYS
Specific viral proteins are transferred on blotting
paper either from a gel or produced by
recombination or peptide synthesis.
Further steps are similar to those of eia.
The viral antigen band on the blotting paper
develops colour if specific antibody to that
particular antigen is present in the serum.
8) ANTIBODY AVIDITY ASSAYS:
The host antibody response matures over several
weeks’ post-acute infection.
Therefore antibody detected > 3 months after acute
infection binds strongly to antigen used in
laboratory assays, as a corollary the antibody in the
first 3 months has weak binding and can be easily
dissociated from the antigen antibody complexes.
SEROLOGICAL TEST
USES2.
TEST USES
COMPLEMEN
T FIXATION
TEST (CFT)
Respiratory viruses-
measures total antibody, to
diagnose recent infection
acute and convalescent
serum samples are required
to show rise in titer.
ENZYME LINKED
IMMUNOSORBENT
ASSAYS – EIA OR
ELISA
Igg/ igm antibody- rubella,
measles, mumps, hiv,
hepatitis a, etc.
IMMUNOFLUROR
ESCENCE- IF
Ige /igm antibody- ebv, vzv
antigen- rsv, influenza and
other respiratory viruses in
respiratory sectetions.
LATEX AND GEL
PARTICLE
AGGLUTINATION
Antibody- rubella,
toxoplsama
Antigen- rotavirus
Norovirus
WESTERN BLOT –
WB AND LINE
ASSAYS -LIA
Used to confirm hiv and hcv
screen positive specimens
IgG AVIDITY
ASSAYS
To confirm recent cmv,
rubella and toxoplasma
infections