-
What is immunohematology
Blood bank
-
What is titration
a method to determine the highest dilution at which agglutination can be detected.
-
What are applications of TITRATION
- 1.Prenatal Studies
- -Monitor maternal IgG antibody
- 2.Antibody Identification
- -CAS (Cold Agglutinin Syndrome)
- -HTLA
-
Application of Titration
What does Titration of maternal IgG antibody entail?
an indicator of the course and severity of hemolytic disease of the fetus and newborn(HDFN).
-Fourfold rise or greater is considered significant
-
What value is given to pathologic cold agglutinins
(>64)
-
What Describes a group of weakly reactive, IgG antibodies that have the unique characteristic of reacting indilutions as high as 1:2048
HTLA (High titer low avidity antibody)
-
Anti-Ch, -Rg, -Csa, - Kna, -McCa all have what in common?
-HTLA (High Titer Low Avidity antibodies)
-Reacts with many cells – difficult to rule out other abs
-These are IgG antibodies but are often NOT clinicallysignificant but may mask other antibodies.
-
What is neutralization?
Inactivation of an antibody resulting from binding with a soluble antigen.
-
What are the known substances that have blood group antigen specificity?
- Hydatid cyst fluid – P1 substance
- Human urine - Sda
- Human serum – Ch, Rg
- Human breast milk - I
-
What is Adsorption?
-to remove antibody from a serumsample by combining it with antigen positivered cells
-
What are some applications of Adsorption?
-Separate multiple antibodies in a single serum sample.
-Remove autoantibody from a sample to permitdetection of alloantibodies.
-Remove unwanted antibody from a serum with anantibody suitable for reagent use. ---
-Confirm the presence of an antigen on a red cell sample by its ability to remove the corresponding antibody from a sample.
-Confirm the specificity of an antibody by showing it canbe adsorbed onto a red cell of known antigen type
-
What are the 2 methods of Adsorption of Antibodies?
- -Autologous adsorption
- -Homologous (Allogeneic) adsorption
-
When is Autologous Adsorption used?
When the patient has not been transfused recently.
-
When is Homologous Adsorption used?
used when apatient has been transfused recently
-
Why cant auto cells be used for Homologous Adsorption?
because you may adsorb alloantibody onto circulating donor cells
-
What cells are used for Homologous Adsorption?
Use red cells of known phenotype to adsorb out the broad specificity autoantibody.
-Usually 3 different cells: R1R1, R2R2, rr,lacking Jka, Jkb, K and s antigens
-
Why do we enzyme treat cells in Homologous Adsorption?
-to make them Fya, Fyb and S antigen negative.
-
What is Elution?
-is a technique used to free the antibody bound to the red cell membrane.
-
What are the methods of Elution?
- 1.Temperature: heat or freeze/thaw
- -Investigation of ABO system antibodies
- 2.Acid or organic solvents
- -Investigation of warm reactive allo or autoantibodies
-
ELUTION APPLICATIONS
-What causes a positive DAT following a transfusion reaction?
-Mixed field DAT due to donor cells in the recipient’s circulation that are coated with IgG
-Eluate is used to identify the alloantibody coating thedonor cells
-
ELUTION APPLICATION
What is associated with to Investigate a positive DAT in a patient with warmautoimmune hemolytic anemia
Characterize the antibody
-
ELUTION APPLICATIONS
What is associated with In combination with adsorption procedures?
- -Detect weak antigen
- -Recover adsorbed antibody
|
|
