Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MLS 416 Immunology and Molecular Diagnostics > Precipitation & Agglutination Reactions > Flashcards

Precipitation & Agglutination Reactions Flashcards

1
Q

Define serology.

A

Study of fluid components in the blood, especially antibodies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define serum.

A

Liquid portions of the blood without coagulation factors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define antigen.

A

A foreign substance that initiates an immune response in the human body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define antibody.

A

A protein produced in response to antigens.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are examples of antibodies?

A

Immunoglobulins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a monoclonal antibody?

A

An antibody that recognizes one epitope.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a polyclonal antibody?

A

Recognizes multiple epitopes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define sensitivity.

A

To correctly identify the patients WITH the given disease you are looking for.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define specificity.

A

To correctly identify the patients WITHOUT the given disease you are looking for.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What types of tests do highly sensitive tests work well?

A

Screening testing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What types of tests do highly specific tests work well?

A

Confirmatory testing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is a qualitative result?

A

The presence or absence of a particular antibody.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a semi-quantitative test?

A

Provide an estimate of the quantity of a patient’s antibodies produced against infection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a quantitative result?

A

A specific amount of analyte.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is a precipitation assay?

A

Soluble antigen combines with soluble antibody which produces a visible, insoluble complex.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is an agglutination assay?

A

An antigen-antibody complex where antigen is bound to a particle or cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a requirement for a precipitation reaction?

A

Antigen and antibody must have multiple binding sites for one another. Equal relative concentration of each.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Define affinity.

A

Amount of initial attraction between antibody Fab site and antigen epitope.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Define avidity.

A

Sum of all the attractive forces between antibody and antigen. The “strength” of the forces.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Define the Law of mass action equation.

A

K = [AgAb]/[Ab][Ag]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

K, from the law of mass action, is dependent on what?

A

The strength of binding between the antibody and antigen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

As K increases, the amount of AgAb complexes form. This causes the reaction to be ___.

A

more visible.

23
Q

Define prozone in the precipitation curve.

A

A large excess of antibody.

24
Q

Define postzone in the precipitation curve.

A

A large excess of antigen.

25
Q

How is the electric current effected with passive gel precipitation.

A

No electric current; slow movement of precipitants.

26
Q

How is the electric current effected with non-passive gel precipitation.

A

Electric current present; fast movement of precipitants.

27
Q

Describe nephelometry.

A

Light scattered at an angle and is measured indicating the amount of antigen or antibody present.

28
Q

In nephelometry, light scatter will ___ when the amount of immune complexes ___.

A

increase; increase.

29
Q

Describe turbidimetry.

A

Measures cloudiness; the reduction of light transmission causes greater absorbance.

30
Q

Describe radial immunodiffusion.

A

A single passive diffusion technique where gel is infused with antibody, and the patient antigen sample is added to wells. Measurement of radius determines antigen concentration.

31
Q

Describe ouchterlony double diffusion.

A

A double diffusion technique where antibody AND antigen diffuse from wells. Lines on the precipitation indicate antigen relationship.

32
Q

What are the three types of patterns with the ouchterlony double diffusion technique?

A

Identity, partial identity, and nonidentity.

33
Q

What type of ouchterlony double pattern is shown?

A

Identity / serological identity.

34
Q

What type of ouchterlony double pattern is shown?

A

Nonidentity.

35
Q

What type of ouchterlony double pattern is shown?

A

Partial identity.

36
Q

Describe immunofixation electrophoresis.

A

A double-diffusion (non-passive technique) that measures antibody isotope levels. Unknown antigens are electrophoresed then antibody (monoclonal) is applied to gel.

37
Q

In immunofixation electrophoresis, when do precipitates form?

A

When antigen-antibody combination forms.

38
Q

In immunofixation electrophoresis, the first lane detects what?

A

All serum proteins.

39
Q

List and describe the two steps of an agglutination reaction.

A

(1) Sensitization: initial binding.

2) Lattice formation: formation of large aggregates (visible

40
Q

What are the two enhancement stains used for AbAg reactions?

A

LISS (low ionic strength saline)

PEG (polyethylene glycol)

41
Q

How does LISS effect reactions?

A

Neutralizes surface charge and cells can get closer together.

42
Q

How does PEG effect reactions?

A

Enhances viscosity and decreases water around cells which brings them closer together.

43
Q

Define AHG (antihuman globulin).

A

(Coombs reagent) Attaches to the Fc portion of IgG and helps to bridge the gap between RBCs so that a visible agglutination reaction can occur.

44
Q

Describe direct antiglobulin (DAT), Coombs test.

A

Antibodies are attached to cells inside the body and AHG is added to a patient’s red cells to cause agglutination.

45
Q

Describe the indirect antiglobulin test (IAT).

A

Patient’s antibodies are added to purchased RBCs. AHG is added to sensitize RBCs which causes agglutination.

46
Q

What are three enhancement factors in AgAb reactions?

A

(1) Temperature.
(2) pH.
(3) Type of antibody.

47
Q

Describe direct agglutination.

A

Antigen is naturally present on the cell or particle.

48
Q

Describe indirect (passive) agglutination.

A

An antigen that is artificially adsorbed to carrier particle or cell.

49
Q

Describe reverse passive agglutination.

A

ANTIBODY is attached to carrier particle or cell. This technique is used to detect if the antigen is present.

50
Q

Determine if this is passive or reverse passive agglutination.

A

Passive.

51
Q

Determine if this is passive or reverse passive agglutination.

A

Reverse passive agglutination.

52
Q

Describe agglutination inhibition.

A

Competition between particulate (purchased antigen) and soluble antigens (patient) for limited antibody-combining sites.

53
Q

In agglutination inhibition, when no agglutination occurs what is this indicative of?

A

A positive result.

MLS 416 Immunology and Molecular Diagnostics (33 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions