Blood Group Antibodies Flashcards
Warm reacting IgG mnemonic- Rich Daring Kidd can Kill MaNs
Rh, Duffy, Kidd, Kell, MNS’
Reacts with an antigen on the patient’s own cells
Autoantibody
Reacts with a foreign antigen not present on the patient’s own erythrocytes
Alloantibody
Antigenic stimulus is unknown; occurs without exposure to antigens
Natural occurring antibodies
Individual exposed to biochemical structures similar to A or B antigens in the environment (bacteria, pollen, plants)
Non-RBC stimulated antibody
Produced after exposure to foreign erythrocyte antigens through transfusion or pregnancy
Immune antibodies
Naturally occurring antibodies characteristics
IgM, React at 4-22°C
Immune antibodies characteristics
IgG, React at 37°C
Clinical significance of IgG
Causes HTR (hemolytic transfusion reaction) and HDN (hemolytic disease of the newborn)
Red cells from homozygous individuals possess more antigens per red cell than those from heterozygous individuals
Dosage effect
pH for antigen-antibody reaction
6.5 to 7.5
Temperature for IgM and IgG antibodies
IgM reacts at room temperature; IgG reacts at body temperature
Biphasic antibody
auto-anti-P
Over centrifugation effect
Causes false positive results
Under centrifugation effect
Causes false negative results
Reagents that enhance IgG antibody detection by reducing zeta potential, promoting antibody uptake, or direct agglutination
Enhancement medium
Increased concentration promotes rouleaux formation in enhancement medium
Bovine serum albumin (22%)
Removes water molecules, enhances antibody detection by reducing surface tension and promoting closer interaction between cells
Polyethylene Glycol (PEG)
Polyethylene Glycol (PEG) incubation
Incubate for 10-30 minutes without centrifuge to avoid false positive results