ELISA

Question 1

\Widely used BIOCHEMICAL ASSAY to detect in a sample the PRESENCE and QUANTITY of PROTEINS

Answer 1

ELISA

Question 2

Examples of proteins that ELISA can detect: (4)

Answer 2

Hormones

Antibodies

Bacteria

Viruses

Question 3

How does ELISA work?

Answer 3

The COUPLING of ANTIGENS and ANTIBODIES. Heavily reliant on specificity and affinity.

Question 4

The ability to discriminate among diverse proteins.

Answer 4

Specificity

Question 5

The ability to tightly bind to molecules

Answer 5

Affinity

Question 6

Antigenic determinants in a bacterial cell

the part of an antigen that the host’s immune system recognizes, eliciting the immune response to an invading pathogen

Answer 6

Epitopes

Question 7

Large GLYCOPROTEIN molecules produced by B-lymphocytes during the HUMORAL immune response to ANTIGENS introduced into the body

Answer 7

ANTIBODIES

Question 8

WHEN and WHAT produces Antibodies?

Answer 8

When: HUMORAL immune response to antigens

What: B-lymphocytes

Question 9

Types of lymphocytes (2)

Answer 9

B-lymphocytes (B-cells)

T-lymphocytes (T-cells)

Question 10

WHITE BLOOD CELLS form from where?

Answer 10

Hematopoietic (blood) stem cells in the bone marrow

Question 11

The model which states that ANTIGENS BIND TO RECEPTOR SITES OF ANTIBODIES

Answer 11

lock-and-key model

Question 12

Can also bind to antibodies following the same principle of the lock-and-key model.

They can bind to the ___ or the ___ part.

Answer 12

Secondary antibodies

Receptor site
Tail

Question 13

ELISA stand for?

Answer 13

ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA)

Question 14

FILL IN THE BLANKS:

ANTIGEN/ANTIBODY of interest is ABSORBED on a PLASTIC SURFACE (___)

___ is RECOGNIZED and BINDS to a specific ___ (___)

The ___ is RECOGNIZED by the ___ which has an ___ attached(___)

___ REACT with the ___ to produce a PRODUCT, usually colored

Answer 14

Sorbent

Antigen - Antibody (immuno)

Antibody - Second Antibody - Enzyme (Enzyme-linked)

Substrate enzyme

Question 15

Examples of what ELISA has been used to detect: (3)

Answer 15

Hepatitis B

Rabies

HIV

Question 16

ELISA is able to detect Hepatitis B, rabies, and HIV through?

Answer 16

Antibodies in the blood serum

Question 17

ELISA is able to MEASURE the AMOUNT of various other proteins such as? (3)

Answer 17

Hormones

Toxins

Allergens

Question 18

INDIRECT ELISA (9)

Answer 18

Binding Known Antigen

Blocking

Washing 1

Adding Test Sample Primary Antibody

Washing 2

Adding Enzyme-linked Secondary Antibody

Washing 3

Adding Substrate

Reading Results

Question 19

Commonly used to read ELISA results

Answer 19

Spectrophotometers (microplate reader)

Question 20

What is the advantage of indirect ELISA?

Answer 20

Signal Amplification

Question 21

In ELISA, TMB (___) plays the role of a ___, and is one of the MOST SENSITIVE SUBSTRATES for HRP.

Answer 21

3,3’ ,5,5’-Tetramethylbenzidine

Chromogenic substrate

Question 22

When a TMB solution is added to HRP, HRP will reduce ___ and oxidize ___, turning it from colorless to BLUE-GREEN

This produces a ___.

Answer 22

Hydrogen peroxide

TMB

Change-transfer complex

Question 23

DETECT ANTIGENS in the sample

It is the MOST COMMONLY USED format.

HIGHLY SPECIFIC which minimizes FALSE POSITIVES

Answer 23

Sandwich ELISA

Question 24

Sandwich ELISA requires ___ for different ___ of the ___.

These (answer above) are normally referred to as ___.

Answer 24

two antibodies

Epitopes

Antigen

Matched antibody pairs

Question 25

Hormone produced during pregnancy

Answer 25

Human Chorionic Gonadotropin (hCG)

Question 26

Parts of a pregnancy test kit (4)

Answer 26

Antigen (hCG)

Colored Anti-hCG Antibody

Fixed Anti-hCG Antibody

Fixed Secondary Antibody