INTRODUCTION Flashcards
In serology, our focus is on what?
Antibody detection
Why do we not use yellow SST in immunosero?
because clot activator such as silica can interfere with antibody reaction.
This can interfere in the antibody detection.
Silica gel
This is defined as the study of host reaction when foreign substances are introduced into the body.
Immunology
These foreign substances are termed as what?
Antigens
When introduced into the body, what can these foreign substances do?
can induce or stimulate the reaction of the immune system
Our immune system cannot identify self from non-self.
True or False
FALSE
Our immune system can identify self from non-self.
Immune system normally respond when a self-agent is present.
True or False
FALSE
Immune system DO NOT normally respond when a self-agent is present.
These non-self agents or foreign agents are basically invaders.
True or False
TRUE
What is an example of foreign agents?
Pathogens
This is the in vitro study of antigen-antibody reaction.
Serology
Serology is the in vivo study of antigen-antibody reaction.
True or False
False
In vitro
What does “in vitro” pertain to?
pertains to reactions outside the body specifically in the test tubes.
What does “sero” mean?
Serum
What is the preferred blood sample or body fluid in antibody detection?
Serum
These are always specific in nature.
Antigen-antibody reactions
These are the ones that will stimulate the immune system to react.
Antigens
What is the product of the immune response to these antigens?
Antibodies
What is always specific to antigen?
Antibody
Why is the detection of antibodies the main focus of serology?
because antibody is a product of immune response against non-self foreign invaders.
If antigen is the focus of the laboratory testing it is called …
reverse serology
they pertain to a specific something that came from an individual.
Sample and specimen
What is the difference between sample and specimen?
Specimen is unprocessed; sample is processed
In the serum sample, what is the target?
antibody
Since antigen-antibody reactions are always specific in nature, therefore, if antibody is the target in the serum, what would be the reagent?
Antigen
What is the target in reverse serology?
Antigen
Why should we perform serum preservation?
to maintain and preserve the constituents in the serum sample.
What are the method/s of preserving the serum sample?
Physical and chemical
How do we physically preserve the serum sample?
By refrigeration
At how many degrees should we refrigerate?
Serum preservation
4-6 degrees Celsius
When the serum is refrigerated, the serum is preserved up to how long?
up to 72 hours (3 days at refrigerator temp)
If you want to maintain the serum sample for a longer period of time, what must be done?
put the serum sample in the FREEZER.
In serum preservation, freezer temperature is …
-18 degrees Celsius or colder
At -18 degrees Celsius or colder, how is the serum sample preserved?
the serum sample is preserved indefinitely.
Lower the temperate, the shorter the serum sample is preserved
True or False
FALSE
the longer the serum sample is preserved
Lower the temperate, the shorter the serum sample is preserved
True or False
FALSE
the longer the serum sample is preserved
How is the serum sample chemically preserved?
with the use of chemical preservatives.
What are the two chemical preservatives?
Merthiolate powder and tricresol/5% phenol
How many grams of merthiolate powder must be added to chemically preserve the serum?
0.001 g merthiolate powder/ mL of serum
How many mL of 5% phenol/tricresol must be added to chemically preserve the serum?
0.1 mL of phenol/tricresol / mL of serum
if you have a 5 mL serum that you need to preserve using Merthiolate powder, how many grams of Merthiolate are you to add?
0.005 g
if you have 3 mL of serum sample that you need to preserve using tricresol, how many mL of tricresol are you to add?
0.3 mL
In the preservation of serum, which of the two methods is commonly performed in the laboratory?
Physical
If you place the serum sample in the freezer, it is only good for how many thawing?
One thawing
After thawing the serum sample, it is good for discarding. You do not re-freeze.
True or False
True
What happens when there is multiple re-freezing?
Multiple re-freezing can damage the constituents of the serum including antibodies
Why do we inactivate serum samples?
To eliminate or destroy unneeded/unwanted serum proteins
In inactivation of serum, what is the primary or main target protein?
complement proteins
What are the two methods to inactivate serum?
Physical and chemical
How is physical inactivation of serum done?
By heating the serum sample
At what temperature and for how long must we heat the serum sample for inactivation?
56 degrees Celsius for 30 minutes
If 30 minutes is too long, how can shorten the heating time?
By increasing the temperature for heating.
To shorten the heating time, at how many degrees must we increase the temperature, and for how long?
60-62 degree Celsius, 3-4 mins
To shorten the heating time, at how many degrees must we increase the temperature, and for how long?
60-62 degree Celsius, 3-4 mins
The shorter the heating time, the higher the temperature must be
True or False
True
How is chemical inactivation of serum done?
By using chemical inactivators.
What is the commonly used chemical inactivator?
Choline chloride
Why must complement proteins be eliminated?
To prevent complement proteins from interfering with the antigen-antibody reaction.
If complement proteins are needed in the procedure/if the test requires complement protein activity, inactivation should still be performed
True or False
False
inactivation should NOT be performed.
it is the lowest amount of an analyte that can be measured by an assay.
Sensitivity
The higher the concentration that can be assayed, the higher is the test sensitivity.
True or False
False
the lower the concentration
it is the detection of a particular analyte in the sample using a particular assay.
Specificity
It is a test that has high specificity and high sensitivity.
Gold standard
These are what we use during confirmatory testing.
Gold standard tests
It is a laboratory that performs gold standard confirmatory tests.
Reference laboratory
What is the Reference laboratory for biochemistry?
Lung Center of the Philippines
What is the reference laboratory for infectious diseases (patients)?
San Lazaro - SACCL
What does SACCL mean?
STD-AIDS Cooperative Council
This is the reference laboratory for infectious diseases for patients.
San Lazaro - SACCL
This is the reference laboratory for infectious diseases for [blood] donors.
TTI-NRL-RITM
What does TTI-NRL-RITM stand for?
Transfusion Transmissible Infections - National Reference Laboratory - Research Institute for Tropical Medicine
It is the sum total strength of interaction between a complex or multivalent antigen and antibody.
Avidity
It is the strength of interaction between a monovalent or simple antigen and antibody.
Affinity
What is the similarity between Avidity and Affinity?
The two pertains to interaction strength.
Wha is the difference between Avidity and Affinity?
The antigen type to which the antibody combines or interacts.
It is the interaction/cross linking/cross bridging of antibodies adjacent to the antigen.
Lattice formation
When there is lattice formation, what is the visible end result?
Agglutination
What is the reciprocal of the highest dilution that shows/presents a positive reaction (i.e., agglutination)?
Titer
What is titer used for?
to report the antibody level/antibody concentration in the serum.
In antibody testing/serology laboratory testing, what are the two methods always done?
Qualitative and quantitative
It is performed to detect the presence of antibodies.
Qualitative method
It is determined through titer measurement.
Quantitative method
If the antibody is present in the serum, in the qualitative procedure, the quantitative method is no longer done.
True or False
False
If the antibody is absent in the serum
What are the Uses/Applications of serology in medicine/science?
DxDxSPF
- Diagnosis of infectious diseases
- Diagnosis of immunological abnormalities
- Serotyping/serologic ID of microorganisms
- Phylogenic classification
- Forensic medicine
What is the outcome when there is a decreased/low specificity in the laboratory procedure?
FACTORS AFFECTING THE OUTCOME OF SEROLOGIC TESTS
False positive
What is the tendency when there is a False positive?
FACTORS AFFECTING THE OUTCOME OF SEROLOGIC TESTS
Tendency for cross-reaction due to its low specificity
Cross-reaction is due to what?
Low specificity
What are examples of the Causes of a False positive outcome?
Bacte, Hemo, Delay
Bacterial contamination, hemolysis, delay in reading slide agglutination test
When there is a false negative result, what is the result?
Decreased/low sensitivity
What is are the causes of a false negative?
Prozone or Post zone
For a true positive reaction to occur, there must be what?
Point of Equivalence
This point is where the antibody concentration/titer must be at equilibrium or proportional to the amount of antigen present.
Point of Equivalence
If levels/concentration of antigen does not equal the amount of antibody, or vice versa, what is a result?
Zonal effect/phenomenon
This is a zonal effect wherein the antibody is excessive to a point that it is no longer proportional to the antigen present.
Prozone
This is a zonal effect wherein the antigen is excessive to a point that it is no longer proportional to the antibody present.
Post zone
What is the reaction when there is a zonal effect/phenomenon causing it be false negative.
There is no visible reaction when there is a ZONAL EFFECT / PHENOMENON
When there is a zonal effect, it is false negative
True or False
True
How can we correct or remedy zonal effects?
Through [serial] dilution
What are the factors affecting the outcome of serologic tests?
+-IOT
- False positive
- False negative
- improper time and temperature of incubation
- Omission of the reagent serum
- Toor early infection
Cross reaction – antibody sharing
True or False
False
antigen sharing
A cross-reaction has what end result?
False positive
In performing serum electrophoresis, antibodies are found where?
Gamma
Antibodies are also known as …
gammaglobulins
What are the commonly tested antibodies in serology.
IgG and IgM
This is the warm-reacting antibody
IgG
This is the cold-reacting antibody
IgM
If target antibody in the serum is IgG, what must be used to optimize the reaction of IgG?
An incubator and water bath
If target antibody in the serum is IgG, what must be used to optimize the reaction of IgG?
An incubator and water bath
If the target antibody in the serum is IgM, what must be done?
incubate at room temperature.
Reagent must always be added first before the sample
True or False
True
This is the time where antibodies are already produced by the patient against the infectious agent.
recovery stage/convalescence stage.
For antibody detection, when must blood be collected?
at the recovery stage/convalescence stage.
There is a high antibody production at the recovery stage
True or False
True
When we test blood from a Px, while they are sick or not at recovery stage, what is the end result? Why?
False Negative; May sakit yung pasyente/infection tas wala lang antibodies kasi hindi pa nagpproduce kaya walang madetect sa test.
It is an immunologic reaction wherein there is a combination of antigens and antibodies.
Primary
This is an immunologic reaction with a nonvisible reaction.
Primary
Since a primary immunologic reaction is a nonvisible reaction, what must be added for you to demonstrate a visible reaction?
LABELS/CONJUGATES
Why must we add labels/conjugates to a primary immunologic reaction?
to demonstrate a visible reaction
These are added to the reagent to demonstrate the positive reaction/end product, and to allow measurement of the product.
LABELS/CONJUGATES
What are the two types of conjugates?
- Non isotopic label
- Isotopic label
these are labels that DO NOT emit radioactivity.
non isotopic label
What are examples of non isotopic lables?
- Enzymes
- Fluorescent probes
- colloidal particles/insoluble particles
What is an example of a non-isotopic labelled procedure?
ELISA
Enzyme-Linked Immunosorbent Assay
these are labels that emit radioactivity.
Isotopic label
What is an example of an isotopic label?
Radioactive iodine
The only laboratory that utilizes isotopic labels are …
NUCLEAR MEDICINE LABORATORIES
An example of primary reaction tests are the …
IMMUNOASSAYS
The name of the immunoassay is based on the label used
True or False
True
Examples wherein the name of the immunoassay is based on the label used:
ELISA, Fluorescent immunoassay, radioimmunoassay
The name of the immunoassay is based on what?
the label used
This immunologic reaction involves demonstrable antigen-antibody reaction.
Secondary
What are the types of immunologic reactions?
Primary, secondary, and tertiary
This immunologic reaction is a visible reaction.
Secondary
Labels/conjugates are still used in the secondary immunologic reactions
True or False
False
no longer used
The procedure for the secondary reaction tests is simple and rapid.
True or False
True
These are used for the basis for routine immunologic/serologic tests.
Secondary reaction tests
This immunologic reaction is used for the basis for routine immunologic/serologic tests.
Secondary immunologic reactions
What are examples of secondary immunologic reactions?
Agglutination and precipitation
This immunologic reaction involves immunologically active in vivo
Tertiary
Tertiary immunologic reactions involve immunologically active in vitro
True or False
False
in vivo
This is an immunologic reaction wherein biologic reactions are detectable.
Tertiary
Examples of tertiary reactions (in vivo reactions) that are demonstrated in vitro
phagocytosis, opsonization, chemotaxis
Among the three reactions, which is the most sensitive and the most specific?
Primary immunologic reactions
excessive antigen
decreased sensi or decreased speci
decreased sensitivity
omission of reagent serum
decreased sensi or decreased speci
decreased sensitivity
too early infection
decreased sensi or decreased speci
decreased sensitivity
cross reaction
decreased sensi or decreased speci
decreased specificity
cross reaction
decreased sensi or decreased speci
decreased specificity
microbial contamination
decreased sensi or decreased speci
decreased specificity
