Lec 11 a

Cards (61)

  • Who is the author of the study material on blood bank reagents and methods?
    Arsham Haile
  • What is the principle behind blood bank tests?
    • Ag + Ab reaction
    • Antigen-antibody interaction
  • What are the routine blood bank testing procedures?
    1. ABO/Rh typing
    2. Antibody screen
    3. Antibody identification
    4. Crossmatch
  • What does ABO/Rh typing detect?
    A, B, and D antigens
  • What is the source of antigens in ABO/Rh typing?
    Patient's RBCs for forward grouping; reagent RBCs for reverse grouping
  • What is the source of antibodies in ABO/Rh typing?
    Reagent anti-A, anti-B, and anti-D for forward grouping; patient's serum for reverse grouping
  • What does the antibody screen detect?
    Specific antibodies to RBC antigens
  • What is the source of antigens in the antibody screen?
    Reagent antibody screening cells
  • What is the source of antibodies in the antibody screen?
    Patient's serum
  • What is the purpose of antibody identification?
    To identify antibodies to RBC antigens
  • What is the source of antigens in antibody identification?
    Reagent antibody panel cells (10-16 cells)
  • What is the source of antibodies in antibody identification?
    Patient's serum
  • What does the crossmatch determine?
    Compatibility of donor RBCs with recipient's blood
  • What is the source of antigens in the crossmatch?
    Donor cells
  • What is the source of antibodies in the crossmatch?
    Recipient's serum
  • What are the types of blood bank reagents?
    1. Reagent RBCs
    2. Antisera
    3. Antiglobulin reagents
    4. Potentiators
  • What do reagent RBCs possess?
    Known antigens
  • What do antisera contain?
    Known antibodies against specific RBC antigens
  • What do antiglobulin reagents contain?
    Poly- or monospecific antibodies against human antibodies
  • What are potentiators used for?
    To enhance the formation of antigen-antibody complexes
  • What are the types of reagent antisera?
    Polyclonal, monoclonal, blended monoclonal
  • What are the uses of ABO antisera?

    To determine if a patient is A, B, AB, or O
  • What colors are the Anti-A and Anti-B reagents?
    Anti-A is blue; Anti-B is yellow
  • How is agglutination read in ABO antisera testing?
    At immediate spin
  • What type of antibodies are Anti-A and Anti-B?
    IgM antibodies
  • What is the purpose of IgG-coated control cells?
    To ensure antiglobulin reagent reactivity in each negative antiglobulin test tube
  • What are A and B cells used for in reverse grouping?
    To confirm front typing results
  • What does Landsteiner's Law state?
    If the patient's RBCs have an antigen, they do not have the antibody in the serum
  • What are antibody screening cells used for?
    To detect antibodies present in a patient's serum
  • Why must antibodies be detected before transfusions?
    To prevent hemolytic transfusion reactions and/or death
  • What do antibody panel cells consist of?
    A panel of RBCs whose antigens are known
  • How many vials are typically in an antibody panel?
    10 to 20 vials
  • What is gel technology used for?
    To detect antigen-antibody reactions
  • What does the microplate method adapt?
    The traditional tube method to the microtiter plate
  • What is the purpose of the indirect antiglobulin test (IAT)?
    To detect in vitro sensitization of RBCs
  • What is the procedure for the IAT?
    Reagent red cells are mixed with patient's serum, incubated at 37°C, washed, and AHG is added
  • What is the purpose of potentiating media?
    To enhance antigen-antibody complex formation
  • What does LISS do?
    Increases antibody uptake of antigen
  • What does bovine albumin allow?
    Allows sensitized cells to come close together to form agglutination lattices
  • What does polyethylene glycol (PEG) do?
    Concentrates antibodies and creates a low-ionic solution for greater antibody uptake