This document discusses the preparation and importance of check cells, which are red blood cells that have IgG antibodies attached to their surface. It describes how check cells are made by pooling O+ red blood cells from multiple donors and incubating them with IgG antibodies to allow the antibodies to attach. Check cells are used as controls in tests like the Coombs test to validate the test results. They help determine if a negative Coombs test is a true negative or a false result. Check cells can be stored for 7 days at 2-6°C or 24 hours at 25°C and are important for validating reagents, tests, and detecting antibodies in other tests.

1. Check cell, Preparation
and Importance
Group members
Farrukh Siyyer
Shahzaib
Hammad Hassan
Habiba Faraz
Rehan Asghar

2. Introduction
• Checks cells are those red blood cells that have immunoglobulins on
there surface
• These are also called sensitized red blood cells
• The antibodies that are attached on the surface of red blood cells are
IgG antibodies
• These antibodies are also called incomplete antibodies because they do
not show agglutination in saline bodies

3. Purpose
• These are used as the control of coombs test or cross match
• The check cells are used when the coombs test is negative to check its
validity
• When the checks are added if it cause agglutination then it means
test is valid
• If it does not cause agglutination it means the test has false result

4. Preparation
Material required:
• O + red blood cells
• Test tubes

5. • Rh antibodies IGg
Normal saline

6. Procedure
• Pool O + red blood cells are required for check cells preparation
• For this purpose we take the blood from 10 O + people because every
person have different concentration of Rh + antigens this is called
pooling
• The blood is taken in the test tube and washed 3 times by normal
saline to get maximum concentration of Rh + antigens on red cells
surface

7. • Then we take 1ml red blood cells from the tube that are pure red blood cells
• Then we add one to two drops IGg antibodies in these red cells and incubate
at 37 ℃
• So the IGg antibodies attached to the red cells surface but some may remain
unattached
• In order to remove these unattached antibodies again we wash the red cells
with normal saline
• Then we obtain red cells that have antibodies attached on its surface these red
cells are called check cells

8. • These check cells can be used for 7 days if these
are stored at 2-6℃
• These can be used for 24 hours if it is kept at
25℃
• The tube should not be exposed to room
temperature it is used in elequates
• We can increase the life span of check cells by
adding
Alsever's solution mostly used in blood banks

9. Importance
• Functional validation of AHG reagents
• Procedural validation of Test
• Direct coombs test
• Compatibility testing
• Antibody screening
• Detection of Du red cells

10. Thank You