use O cell tube on lab for:
- A- As control.
- B- To detect Ag.
- C- To detect Ab.
The correct answer is C- To detect Ab (antibodies).
Here's a more detailed explanation:
- O cell tube:
A test tube containing red blood cells from a group O donor. These cells lack both A and B antigens on their surface.
- Purpose in the lab:
- Detecting antibodies in patient serum or plasma: When a patient's serum or plasma is mixed with O cells, any antibodies directed against A or B antigens will cause agglutination (clumping) of the O cells. This is because O cells lack A and B antigens, so any antibodies against these antigens will freely bind to them.
- Ruling out false-positive reactions: In some tests, O cells are used to rule out non-specific agglutination that might be caused by factors other than antibodies.
- Specific uses:
- Antibody screening and identification: O cells are used in blood bank testing to screen for unexpected antibodies in patient blood that could cause transfusion reactions.
- ABO blood typing: O cells can be used to confirm ABO blood type in certain cases.
- Cold agglutinin testing: O cells are used to detect cold agglutinins, which are antibodies that can cause red blood cells to clump together at cold temperatures.
- Not used for:
- Ag (antigen) detection: O cells themselves do not contain A or B antigens, so they cannot be used to detect these antigens.
- Control purposes: While O cells can be used to rule out false-positive reactions, they are not typically used as a primary control in laboratory testing.
