Immunohematology Flashcards
T or F: RBC’s carry MHC molecules
False
T or F: Platelets carry MHC molecules
True. People repeatedly needing platelets, which do bear HLA (Class I), they may develop an alloimmunization problem, in which case HLA typing as well becomes necessary.
What are blood group antigens?
Blood group antigens are glycolipids found on the surface of all body cells, including of course red cells
What are A, B or O. Blood group substances ?
glycoproteins with similar sugars, found in the body fluids of people who have the Secretor (Se) phenotype
What is the most common blood groups?
O type and Rh+
Least common blood groups?
AB type and Rh-
Group A plasma antigen and possible genotype?
- Anti-B
- AA or AO
Group B plasma antigen and possible genotype?
- Anti-A
- BB or BO
Group AB plasma antigen and possible genotype?
- None
- AB
- universal recipient
Group O plasma antigen and possible genotype?
- Anti-A & B
- OO
- Universal Donor
What is the the Bombay phenotype (Oh)?
some people who lack the transferase gene that puts the final sugar on the “core”, and thus do not express even the H antigen. Very rare. All blood, even type O, is foreign to such people.
What are ISOHEMAGGLUTININS?
Very common in environment and you will become immunized to them. These antibodies are sometimes called “naturally-occurring,” although like all antibodies we believe that their production is in response to antigenic stimulation. Are of the IgM class
What allele do we care about for Rh factor?
D allele
Is Rh an isoheamagglutinin?
No. you don’t make antibody to it unless you’re Rh(D)- and become immunized with Rh(D)+ red cells.
Define crossmatching.
antibodies in a recipient’s plasma which can react with antigens on donor’s red blood cells. The crossmatch therefore is a lab test in which plasma from the prospective recipient is mixed with red cells from the prospective donor and observed for agglutination.
