Specimens for IHC

Question 1

Specimen is prepared as cryostat section and must be fixed

Answer 1

Frozen Section

Question 2

Frozen Section is carried out

Answer 2

Intra-operatively

Question 3

Frozen Section is used for

Answer 3

RAPID DIAGNOSIS

Question 4

Purpose of Fixation in IHC

Answer 4

1. Preserve position of the antigens being detected
2. Prevent destruction of labile antigenic sites

Question 5

Microtomes used for Cutting specimen in IHC

Answer 5

1. Freezing
2. Cryostat

Question 6

Fixative agent used for IHC Frozen Section specimen

Answer 6

1. Methanol
2. Acetone

Question 7

2 Types of Processed Specimens

Answer 7

1. Formalin-fixed
2. Paraffin embedded

Question 8

Process of retrieving antigens and transferring it into the glass slide

Answer 8

Antigen Retrieval

Question 9

Most commonly used fixative in IHC

Answer 9

Formaldehyde

Question 10

Method only done for formalin-fixed and paraffin embedded specimen

Answer 10

Pre-treatment blocking

Question 11

2 Types of Pre-treatment blocking

Answer 11

1. Peroxidase Blocking
2. Protein Blocking

Question 12

Blocks endogenous peroxidase

Answer 12

Peroxidase block

Question 13

Substances that is being used for Peroxidase blocking

Answer 13

3% Hydrogen Peroxide

Question 14

Type of pretreatment blocking that Blocks non-specific site and reduces background

Answer 14

Protein blocking/ Protein block

Question 15

Protein block uses what substance

Answer 15

10% normal serum

Question 16

Preferred pre-treatment blocking

Answer 16

Protein block

Question 17

2 General Methods for Antigen Retrieval

Answer 17

1. Heat Induced Epitope Retrieval
2. Protease Induced Epitope Retrieval

Question 18

Enzymes being used in PIER

Answer 18

1. Trypsin
2. Protease

Question 19

Methods under HIER

Answer 19

1. Microwave
2. Pressure cooker
3. Water bath, autoclave, and steamer heating
4. Decloaker heating
5. microwave and enzyme
6. Digestion

Question 20

Less time consuming HIER method

Answer 20

Pressure cooker

Question 21

A HIER method that runs for 20 mins

Answer 21

Microwave

Question 22

Purpose in the use of CONTROLS in IHC

Answer 22

1. Test for specificity of antibodies involved
2. Prevent misinterpretation of false (-) and false (+)

Question 23

Control: Tissue with antigen

Answer 23

Positive control

Question 24

Control: omitting primary antibody from staining or replacing primary antibody with IgG that is directed against an unrelated antigen

Answer 24

Negative Control

Question 25

Also known as Built In control

Answer 25

Internal Tissue Control

Question 26

Built In control contains

Answer 26

Target antigen in tissue elements and adjacent normal tissue elements