(F) IS Lab L2

https://docs.google.com/document/d/1MmzUfQ_jJuFrHWVXmHWtylTKwgXtiwnxxA7lH3zikg0/edit?usp=sharing

D

Which of the following hepatitis viruses is a bloodborne virus often found as a coinfection with the Hepatitis C Virus (HCV)?

• a. Hepatitis A Virus (HAV)

• b. Hepatitis B Virus (HBV)

• c. Hepatitis E Virus (HEV)

• d. Hepatitis G Virus (GBV-C)

• e. Hepatitis D Virus (HDV)

C

Hepatitis E Virus (HEV) is clinically significant because it can cause fulminant hepatitis in which specific demographic?

• a. Immunocompromised elderly patients

• b. Newborns and infants

• c. Pregnant women during the third trimester

• d. Patients with concurrent HIV infection

• e. Organ transplant recipients

B

Which of the following describes the causative agent of German Measles?

• a. An enveloped, double-stranded DNA virus

• b. An enveloped, single-stranded RNA virus

• c. A non-enveloped DNA virus

• d. A retrovirus

• e. A cell-associated DNA virus

E

Which rare but fatal late complication is associated with the Rubeola virus (Measles)?

• a. Congenital Rubella Syndrome

• b. Infectious Mononucleosis

• c. Fulminant Hepatitis

• d. Kaposi Sarcoma

• e. Subacute Sclerosing Panencephalitis (SSPE)

C

Cytomegalovirus (CMV) is a large, enveloped DNA virus that belongs to which viral family?

• a. Retroviridae

• b. Paramyxoviridae

• c. Herpesviridae

• d. Hepadnaviridae

• e. Flaviviridae

D

To prevent CMV transmission via blood transfusions, which specific blood component must be removed or avoided, as the virus is found inside them?

• a. Erythrocytes (RBCs)

• b. Platelets

• c. Plasma

• d. Leukocytes (WBCs)

• e. Coagulation factors

A

Which classic microscopic finding is indicative of a Cytomegalovirus (CMV) infection?

• a. "Owl's eye" inclusion bodies

• b. Downey cells

• c. Negri bodies

• d. Koplik spots

• e. Reed-Sternberg cells

C

Which HIV gene encodes for core and structural proteins, specifically the p24 core protein used for early diagnosis?

• a. pol gene

• b. env gene

• c. gag gene

• d. tat gene

• e. rev gene

D

During the HIV replication cycle, which envelope protein mediates the fusion of the virus with the host cell?

• a. gp120

• b. p24

• c. reverse transcriptase

• d. gp41

• e. integrase

D

According to the HIV Diagnostic Algorithm, if the fourth-generation HIV Ag/Ab test is reactive, what is the next step?

• a. NAAT/PCR testing

• b. CD4+ T Lymphocyte Testing

• c. Western Blot confirmation

• d. HIV-1/HIV-2 antibody differentiation test

• e. Viral load testing

B

Infectious Mononucleosis (IM) presents with a hallmark hematologic finding of atypical lymphocytes. What are these cells specifically called?

• a. Reed-Sternberg cells

• b. Downey cells

• c. CD4+ cells

• d. Kupffer cells

• e. Owl's eye cells

C

In the Davidsohn Differential Test, what is the specific absorption pattern for Infectious Mononucleosis (IM)?

• a. Absorbed by both guinea pig kidney and beef RBCs

• b. Absorbed by guinea pig kidney only

• c. Not absorbed by guinea pig kidney, but IS absorbed by beef RBCs

• d. Not absorbed by either guinea pig kidney or beef RBCs

• e. Absorbed by sheep erythrocytes only

A

What is the main characteristic that differentiates heterogeneous immunoassays from homogeneous immunoassays?

• a. Heterogeneous assays require the physical separation of bound and free components.

• b. Heterogeneous assays are used only for small haptens.

• c. Heterogeneous assays require enzymes, while homogeneous assays do not.

• d. Heterogeneous assays do not use solid-phase materials.

• e. Heterogeneous assays are performed entirely in solution.

C

Homogeneous immunoassays are especially useful for testing which of the following?

• a. Large antigens with multiple epitopes

• b. Whole viral particles

• c. Small molecules such as drugs and hormones

• d. Cellular components like CD4 cells

• e. Fluorescent-labeled nucleic acid probes

E

In Enzyme Immunoassays (EIA), which common enzyme label is used to produce measurable reaction products through glucose oxidation?

• a. Horseradish peroxidase (HRP)

• b. Alkaline phosphatase (ALP)

• c. B-Galactosidase

• d. Glucose-6-phosphate dehydrogenase

• e. Glucose oxidase

B

In which type of ELISA is the patient antigen "sandwiched" between a solid-phase capture antibody and a labeled detection antibody?

• a. Indirect ELISA

• b. Sandwich ELISA

• c. Competitive Enzyme Immunoassay

• d. Capture Enzyme Immunoassay

• e. Inhibition Immunofluorescence Assay

B

In a Competitive Enzyme Immunoassay, how is the result interpreted regarding the concentration of patient antigen?

• a. High patient antigen leads to high enzyme activity (directly proportional).

• b. High patient antigen leads to low enzyme activity (inversely proportional).

• c. Low patient antigen leads to low enzyme activity.

• d. Enzyme activity remains constant regardless of patient antigen.

• e. Patient antigen concentration has no effect on color development.

A

What is the fundamental principle of Chemiluminescence Immunoassay (CLIA)?

• a. It involves the production of light as a direct result of a chemical reaction.

• b. It uses light generated through complementary nucleic acid hybridization.

• c. It relies on the agglutination of horse RBCs to produce a visual signal.

• d. It initiates light generation through an electrochemical process.

• e. It uses fluorescently labeled secondary antibodies for signal amplification.

C

Which important chemiluminescent label is known for producing a rapid flash of light?

• a. Luminol

• b. Peroxyoxalates

• c. Acridinium esters

• d. Dioxetanes

• e. Ruthenium complexes

D

Electrochemiluminescence Immunoassay (ECLIA) is distinct from CLIA because it initiates light generation through an electrochemical process. What specific complex does ECLIA utilize in combination with magnetic beads?

• a. Acridinium esters

• b. Luminol

• c. Horseradish peroxidase

• d. Ruthenium complexes

• e. Alkaline phosphatase

D

Which assay involves a fluorescent-labeled antibody binding directly to the target antigen, commonly used to detect the rabies virus?

• a. Indirect Immunofluorescence Assay (IFA)

• b. Fluorescent Antinuclear Antibody Test (FANA)

• c. Fluorescence in situ Hybridization (FISH)

• d. Direct Immunofluorescence Assay (DFA)

• e. Electrochemiluminescence Immunoassay (ECLIA)

C

The Indirect Immunofluorescence Assay (IFA) utilizes an unlabeled primary antibody followed by a fluorescent-labeled secondary antibody. What is the main advantage of this technique over DFA?

• a. It requires no washing steps.

• b. It uses ruthenium complexes.

• c. It provides signal amplification.

• d. It is exclusively for nucleic acid detection.

• e. It produces a direct chemical reaction resulting in light.

B

The Fluorescent Antinuclear Antibody Test (FANA) is traditionally performed using which specific technique to detect autoantibodies directed against components of the cell nucleus?

• a. Direct Immunofluorescence Assay (DFA)

• b. Indirect Immunofluorescence Assay (IFA)

• c. Fluorescence in situ Hybridization (FISH)

• d. Chemiluminescence Immunoassay (CLIA)

• e. Competitive ELISA

A

Fluorescence in situ Hybridization (FISH) differs from conventional immunoassays because its fundamental recognition mechanism is based on:

• a. Complementary nucleic acid hybridization

• b. Heterophile antibody cross-reactivity

• c. Antigen-antibody binding

• d. Viral replication hijacking

• e. Substrate hydrolysis

C

In the context of HIV genetics, which viral gene encodes for reverse transcriptase, integrase, and protease?

• a. env gene

• b. gag gene

• c. pol gene

• d. p24 gene

• e. gp120 gene

E

Which class of immunoassay typically requires the control line to validate the test, and in which a positive result is indicated by the disappearance of a line (analyte blocks labeled Ag from binding)?

• a. Sandwich Immunoassay

• b. Homogeneous Immunoassay

• c. Direct Immunofluorescence Assay

• d. Indirect ELISA

• e. Competitive Immunoassay

D

When an HIV RNA NAAT/PCR test is performed during the diagnostic algorithm, what does a positive result strongly indicate?

• a. Past immunity to HIV

• b. A false-positive screening result

• c. Congenital HIV syndrome

• d. An acute HIV infection

• e. Subclinical latency

C

Which of the following accurately describes the Paul-Bunnell Test for Infectious Mononucleosis?

• a. It is a chemiluminescence assay detecting specific EBV DNA.

• b. It uses complementary nucleic acid hybridization.

• c. It is a hemagglutination screening test detecting heterophile antibodies using sheep erythrocytes.

• d. It detects atypical lymphocytes via flow cytometry.

• e. It measures specific IgM anti-VCA levels.

C

What specific HIV envelope glycoprotein is responsible for initially binding to the host CD4 receptor?

• a. gp41

• b. p24

• c. gp120

• d. reverse transcriptase

• e. protease

B

In the Davidsohn Differential Test, what substance specifically absorbs Forssman antibodies but does NOT absorb Infectious Mononucleosis (IM) antibodies?

• a. Beef erythrocytes

• b. Guinea pig kidney

• c. Horse erythrocytes

• d. Sheep erythrocytes

• e. Ruthenium complexes

Hepatitis G / GBV-C

Name the bloodborne virus that is often found as a coinfection with the Hepatitis C Virus (HCV).

Fecal-oral route

What is the specific transmission route for the Hepatitis E Virus (HEV), which links it strongly to poor sanitation?

IgM anti-HEV

Which immunologic marker indicates an acute or recent Hepatitis E infection and is short-lived?

Fulminant hepatitis

What severe liver condition can Hepatitis E (HEV) cause specifically in pregnant women during their third trimester?

Congenital Rubella Syndrome (CRS)

What is the severe condition that occurs when a rubella infection happens during pregnancy, especially during the first trimester?

Subacute Sclerosing Panencephalitis (SSPE)

What rare but fatal late complication can arise from an infection with the Rubeola virus (Measles)?

WBCs / Leukocytes

Which specific type of blood cells does Cytomegalovirus (CMV) infect, requiring the use of leukoreduced blood for transfusions?

"Owl's eye" inclusions

What is the descriptive term for the microscopic inclusion bodies classically found in a Cytomegalovirus (CMV) infection?

CD4 cell / CD4+ T lymphocyte

In HIV biology, what is the primary target cell that the virus attacks, leading to severe immune deficiency?

pol gene

Which major HIV gene encodes for vital enzymes required for viral replication, including reverse transcriptase, integrase, and protease?

p24 core protein

What is the specific viral protein encoded by the gag gene that is widely used as a marker for early HIV diagnosis?

Fourth-generation HIV Ag/Ab test

In the HIV testing algorithm, what is the preferred first-step screening test that detects both the p24 antigen and HIV antibodies?

Flow cytometry (FACS)

What gold standard method is used for CD4+ T Lymphocyte Testing to measure immune function and stage HIV disease?

Downey cells

What is the name of the atypical lymphocytes commonly found as a hallmark hematologic finding in Infectious Mononucleosis?

Heterophile antibodies

What type of antibodies are produced during the acute phase of Infectious Mononucleosis that cross-react with animal RBCs but NOT with EBV-specific antigens?

Monospot Test

What is the rapid test for Infectious Mononucleosis where horse RBCs are agglutinated by heterophile antibodies?

Beef erythrocytes / Beef RBCs

In the Davidsohn Differential Test, what specific type of red blood cells completely absorbs the antibodies of Infectious Mononucleosis?

Heterogeneous Immunoassays

What broad category of immunoassays requires the physical separation of bound and free components via washing or centrifugation?

Homogeneous Immunoassays

Which type of immunoassay does not require physical separation and is especially useful for measuring small haptens like drugs and hormones?

Horseradish peroxidase (HRP)

What is the common enzyme label used in color-producing Enzyme Immunoassay reactions?

Sandwich ELISA

Which type of ELISA format involves the patient antigen being captured between a solid-phase capture antibody and a labeled detection antibody?

Low enzyme activity (Inversely proportional)

In a Competitive Enzyme Immunoassay, if the patient has a high concentration of target antigen, how does this affect the resulting enzyme activity?

Control Line

What specific feature must always appear in both Competitive and Non-Competitive immunoassays to validate that the test works properly?

Chemiluminescence Immunoassay (CLIA)

What immunoassay technique involves the production of light as a direct result of a chemical reaction, often using labels like luminol?

Acridinium esters

What type of chemiluminescent label is specifically known to produce a rapid flash of light?

Electrochemiluminescence Immunoassay (ECLIA)

What advanced immunoassay system utilizes ruthenium complexes combined with magnetic beads and initiates light generation through an electrochemical process?

Indirect Immunofluorescence Assay (IFA)

Which immunofluorescence assay uses an unlabeled primary antibody followed by a fluorescent-labeled secondary antibody to provide signal amplification?

Fluorescent Antinuclear Antibody Test (FANA)

Which laboratory test is used to detect autoantibodies directed against components of the cell nucleus and is traditionally performed using the IFA technique?

Fluorescence in situ Hybridization (FISH)

What specific technique utilizes fluorescently labeled nucleic acid probes to detect specific DNA sequences rather than relying on antigen-antibody binding?

Complementary nucleic acid hybridization

What is the fundamental recognition mechanism utilized by Fluorescence in situ Hybridization (FISH)?

IgM anti-VCA

EBV-Specific Serologic Markers

• Acute infection.

IgG anti-VCA

EBV-Specific Serologic Markers

• Past or current infection.

IgG anti-EA-D

EBV-Specific Serologic Markers

• Active infection.

IgG anti-EA-R

EBV-Specific Serologic Markers

• Found in the serum of very young children, but not in young adults.

Epstein-Barr Nuclear Antigen (EBNA)

EBV-Specific Serologic Markers

• Found in the nucleus of ALL EBV-infected cells.