Blood Groups/Types. Blood Group Terms Antigens: chemical structures imparting specific properties to...
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Transcript of Blood Groups/Types. Blood Group Terms Antigens: chemical structures imparting specific properties to...
Blood Groups/Types
Blood Group Terms
• Antigens: chemical structures imparting specific properties to the surface of the RBC
• Antibodies: protein substance developed in response to foreign body substances
Blood Group Systems
• Detected on the basis of specific reaction with corresponding antibody (either agglutination, lysis, or hemolysis) as a result of the presence or absence of the blood protein antigens on the RBC surface
• Inherited according to Mendelian laws• Fully formed either at birth or in early
postnatal life & persist throughout life
ABO System
• Discovered by Landsteiner in 1900
• Prior to discovery, blood transfusions were hit or miss
• Type A, Type B, Type AB, & Type O
Type A
• 41% of population
• Has A antigens on the RBC surface
• Has anti-B antibodies in the plasma
• Genotypes AA & AO = Phenotype A
Type B
• 10% of population
• Has B antigens on the RBC surface
• Has anti-A antibodies in the plasma
• Genotype BB & BO = Phenotype B
Type AB
• 4 % of population• Has A & B antigens on the RBC
surface• Has NO antibodies in the plasma• Universal Recipient: can receive
Type A, Type B, Type AB, or Type O blood NO antibodies in plasma to react with antigens
• Genotypes: AB = Phenotype AB
Type O
• 45% of population• Has NO antigens on RBC surface• Has anti-A & anti-B antibodies in the
plasma• Universal Donor: can be given to
any blood type no antigens on the RBCs
• Genotype OO = Phenotype O
Rh System
• Discovered by Landsteiner & Wiener in 1937
• Discovered in the Rhesus monkey
• Rh is an antigen on the RBC surface
• Rh + has the antigens on the RBC (85% of population)
• Rh – does NOT have the Rh antigens
• Rh + can accept Rh + or Rh – blood
• Rh – can accept ONLY Rh - blood
Rh Incompatibility
• When Rh– person receives Rh+ blood in a transfusion person develops antibodies against the Rh+ factor
• Clinical problem if second transfusion of Rh+ blood given Rh antibodies will clump with the Rh antigens
• S & S of transfusion reaction: chills, fever, rash, itching, SOB, nausea, nephralgia, hematuria, shock & death
Erythroblastosis fetalis
• Rh– mother and Rh+ father Rh+ child 1st pregnancy
• Mother develops antibodies to baby’s Rh+ antigens
• 2nd pregnancy with Rh+ child mother’s anti-Rh antibodies attack unborn child’s RBCs
• Prevention: shot of Rhogam shortly after birth of first Rh+ baby to block development of antibodies
Erythroblastosis fetalis
• Antigen-antibody reaction due to mixing of Rh+ blood of fetus with Rh- blood of mother during 2nd Rh+ pregnancy
• Prevented with shot of Rhogam at birth of 1st Rh+ baby