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A patient with long term, untreated, HIV will present what findings on a flow cytometer?

Depleted numbers of CD4+ lymphocytes; normal numbers of CD8+ lymphocytes

Laser light is:

A single wavelength (color) of light

Select the incorrect statement from the given.

Antibodies used in immunoassays are typically non-specific

General cell complexity is determined by what in flow cytometry?

Side scatter

How are cells separated in the FACS method?

By charge

Flow cytometry is useful for identification of cells.

True

Laser light is multicolored.

False

CD marker present in all B cells

CD19

CD marker present in all T cells

CD3

CD markers present on T helper

CD3+, CD4+, CD8-

CD markers present on T cytotoxic

CD3+, CD4-, CD8+

CD markers present on NK cell

CD2+, CD4-, CD8-

Forward scatter

used to classifi size of cell

Side scatter

used to assess cell granularity

Gating

The process of selecting specific populations of cells based on their characteristics during flow cytometry analysis.

The greatest amount of side scatter in flow cytometry is observed in what cells?

granulocytes.

A common method for identifying SLE is:

ANA/IFA

A primer is a small, complementary to a parent strand, piece of DNA (or RNA).

true

DNA analysis

southern blotting

RNA analysis

techniques like Northern blotting

Protein analysis

methods such as Western blotting

Match the following steps of the PCR process to their step in the process.

Primer annealing

second

DNA denaturation

first step

Extension

third step

PCR methods do not require primers.

false

Reverse-transcriptase polymerase chain reaction (RT-PCR) applications are most appropriately used for:

Identification of RNA based viruses

The Western Blot combines which two techniques?

Electrophoresis and IFA

The name of the product of PCR is an:

amplified

The use of bacterial restriction enzymes to cleave DNA samples and then compare them to a known a DNA sample via gel electrophoresis/staining is a method known as: 

Restriction Fragment Length Polymorphism

What molecular method is particularly used to identify whole chromosome sections fixed on a glass slide?

FISH

A capture EIA immunoassay is used to detect what class of antibody in a suspected rubella infection?

IgM antibodies

An immunoassay that operates in the manner:

Capture antibody --> antigen of interest --> antibody 1 --> fluorescent labeled antibody 2

Would be best and most completely described as what sort of immunoassay?

Indirect immunofluorescent assay

Antigens can be synthesized and/or labeled in for use in immunoassays.

True

EMIT is what type of immunoassay?

Competitive

Has excess binding sites:

Non competitive

Has excess antibody:

Non competitive

Has excess antigen:

competitive

Signal is proportional to the amount of analyte bound

Non competitive

Uses solid phase components:

Heterogeneous

Uses only aqueous phase components:

Homogeneous

Does not require a washing step:

Homogeneous

Is faster:

Homogeneous

Immunoassays can be used to detect:

specific antibodies or antigens in a sample.

What type of test is used to screen for antibodies to HIV?

An ELISA test

What type of test is commonly used in identifying marijuana use?

EMIT

Which best describes a “sandwich immunoassay”?

Use of a capture and labeled antibodies

Which immunoassay technique produces a inversely proportional signal, with a linear "calibration" curve?

A competitive immunoassay.

A 1:2 dilution is performed 9 times.

What is the final dilution value?

1:512

A patient sample does not demonstrate reactivity at dilution 1:1.

The patient unequivocally does not have an infection.

False

All vaccinations (polio, tetanus, MMR, etc.) remain effective for the life of the person they are administered to (assume 70+ years).

False

A cell count is attempted on a 1:1 patient sample, but the cells are too numerous to count.

A cell count is performed on the 1:32 dilution of the patient sample, and 16 cells are counted.

What value should be reported for the cell count? 

512

Determine the titer from the given observations:

Dilution	1:1	1:2	1:4	1:8	1:16	1:32	1:64	1:128	1:256
Reactivity	+	+	+	+	+	+	+	+	=

1:128

If a serum sample has been diluted 1:64 and reacts positively with the antigen suspension used in the testing process; the next highest dilution of 1:128 does not give a positive reaction.

The titer is read as:

1:64

A ______ pipet requires that the tip be blown out once the initial aliquot is delivered.

TC

A [ Select ] pipet does not require that the tip be blown out once the initial aliquot is delivered.

TD

Semi-automatic fixed volume pipets (MLA style) are [ Select ] variants.

TD

Semi-automatic adjustable volume pipets (Eppendorf style) are [ Select ] variants.

TC

Titers for potential disease state of 3 patients are given:

Patient	Titer
Al	1:16
Bob	Non reactive
Chuck	1:1

 

Rank each patient according to their potential amount of infection where 1 = least infection, 3 = most infection.

Al 3

Bob 1

Chuck 2

312

A patient has a known syphilis infection.

On day 0 the patient's titer is 1:32.

The patient is prescribed a course of antibiotics and is to be tested 4 weeks later.

On day 28 the patient's titer is 1:128.

What can be said about the patient's state of health?

The infection is getting worse; likely due to non-compliance of the antibiotic regiment

A patient is undergoing treatment for a serologically monitored pathological condition.

Standard protocol is to compare day 0 titers to day 14 titers to monitor efficacy of treatment.

The following titers were noted:

Day 0: 1/32

Day 14: 1/16

By what factor has the titer changed? 2x

Does the patient's state of health APPEAR to be improving or worsening? [ Select ] ["Improving", "Worsening"]

According to ASCP guidance is the change in titer significant or not?

Improving & not significant

A procedure calls for 0.025 mL of sample.

Which of the given pipet options would be most appropriate to draw and dispense the required amount?

10 - 50 microliter range adjustable

Which patient can be assumed to have the stronger infection?

	1:1	1:2
Tomax	+	+
Xamot	+	=

Tomax

A procedure calls for 0.001 mL of sample.

You only have pipets calibrated in microliter volumes.

What mathematical operation would you perform to convert 0.001 mL to microliters?

Multiply by 1E+3

The overall charge on a red blood cell's surface (normal; untreated) is:

negative

The most efficient class of antibodies to cause agglutination are:

IgM antibodies.

Which of the reagents listed DOES NOT affect charge on red blood cells?

PEG

Under normal conditions, red blood cells tend to:

Repel each other

The first step in agglutination is:

Attachment of antibody molecules to antigens on the RBC membrane

The addition of too much antibody in a precipitation test will result in the antibody-antigen ratio to be in the:

Prozone

If a slide agglutination test is rotated for less than 1 minute, as the directions specify, what source of error can occur?

Possible false-negative

Have the greatest span for crosslinking

IgM

Responsible for acute blood transfusion reactions

IgM

Agglutinate best at 37 degrees C

IgG

Agglutinate best at room temperature

IgM

An antibody that is heterophilic is best defined as one that:

Reacts with antigens present on red blood cells of multiple species

MRSA

Latex agglutination test is used to identify

Syphilis

Flocculation

Mono

Latex ag Or hema

Mono

hemagglutination

To improve sensitization in agglutination tests [ Select ] ["IgG", "Centrifugation", "IgM", "Addition of LISS"] is useful, regardless of antibody class.

To promote lattice formation [ Select ] ["Addition of LISS", "IgM", "IgG", "Centrifugation"] is necessary.

Incubation promotes sensitization for the IgG class of antibodies.

Addition of LISS & Centrifugation

A patient has their blood typed. The results of the tests are as follows:

Patient blood with Anti-A: +

Patient blood with Anti-B: +

(+ indicates agglutination was observed)

What can be said about the patient's blood?

The patient has type AB blood

A blood bank procedure calls for the addition of 2 drops of antibody reagent for an agglutination test.

If too much antibody is added (too many drops) what incorrect result may be observed?

 

False negative

A blood bank procedure calls for the addition of 2 drops of antibody reagent for an agglutination test.

If too little antibody is added what incorrect result may be observed?

 

False negative