WK13: Neutralization Test

Question 1

A subset of these antibodies can block infection by a process called _____

Answer 1

neutralization

Question 2

Indicator cells of neutralization tests

Answer 2

Laboratory animals or tissue culture

Question 3

2 types of neutralization tests

Answer 3

Toxin Neutralization test

Virus Neutralization test

Question 4

The toxin or virus to be assayed should have known effects on the indicator system which is neutralized by using _______

Answer 4

anti-toxin

Question 5

antigen-antibody reaction in which the biological effects of viruses and toxins are neutralized by homologous antibodies known as neutralizing antibodies

Answer 5

Neutralization

Question 6

diphtheria toxin-antitoxin neutralization test done to assess the immune status of a person

Answer 6

Schick test

Question 7

Schick test is performed by intradermal injection of 0.1 mL of a ________

Answer 7

purified standardized toxin

Question 8

True or false

Inflammation in the site 4-7 days after the performing the Schick test indicates that the antitoxin is present in the px

Answer 8

False (not present)

Question 9

Opalescence on egg yolk agar produced by α-toxin of Clostridium perfringens

Answer 9

Nagler’s reaction

Question 10

Clostridium perfringens is inhibited when ______ is added

Answer 10

anti-alpha-toxin

Question 11

Test for scarlet fever

Answer 11

Dick’s test

Question 12

Antitoxin therapy neutralizes the toxins of _____, _______ and ______

Answer 12

Corynebacterium diphtheriae
Clostridium tetani
Clostridium botulinum

Question 13

This neutralization activity is the basis of virus neutralization assays, sensitive assays used for diagnoses of viral infections

Answer 13

Virus neutralization test

Question 14

___________ can neutralize viral infections resulting in the formation of large antibody-virus complexes

Answer 14

Antiviral antibodies

Question 15

determines if an antibody present in patient serum or mucosal surface can neutralize the infectivity of a virus

Answer 15

Virus neutralization test

Question 16

provides intestinal immunity against poliovirus

Answer 16

mucosal sIgA

Question 17

True or False

A positive neutralization test indicates that the patient has antibodies and has been exposed to the virus

Answer 17

True

Question 18

Neutralization tests have been developed for _____ and _____

Answer 18

arbovirus

rabies virus

Question 19

True or False

The wells with numerous plaques (white patches) contain a high concentration of antibodies.

Answer 19

False (low concentration)

Question 20

During the course of a viral infection, the patient will mount an antibody response to the virus, and we can quantify those antibodies using a ________.

Answer 20

plaque reduction assay

Question 21

The titer is defined as the reciprocal of the highest dilution showing a ____ reduction in plaques.

Answer 21

50%

Question 22

True or False
The presence of antibodies in the patient’s serum tells us whether the patient is currently infected or was infected in the past.

Answer 22

False (does not tell us if px has been infected)

Question 23

Inhibition of rabies and hepatitis A and B viruses infections early in the incubation period by injecting antibodies against these viruses

Answer 23

Passive immunization