Blood Typing Lab STEM Whodunit Practice Lab Blood

Blood Typing Lab STEM Whodunit? Practice Lab

Blood Typing • What’s your blood type? ex. , mine is O+ • ABO and Rh factors are totally independent of each other

ABO Antigens and Antibodies Surface Antibodies Antigens A A Anti-B B B Anti-A AB A, B none O none Anti-A Anti-B

The Rh Factor • Also called D antigen • Either Rh positive (Rh+) or Rh negative (Rh-) Surface Antigens Rh+ Rh factor Rh- none

Blood Type Test • Determines blood type and compatibility Figure 19– 7

Blood Types • Genetically determined cell surface markers (antigens) on RBCs, including – ABO group – glycolipids on RBC surface – Rh factor – membrane protein

4 Basic Blood Types • • A has surface antigen A B has surface antigen B AB has both antigens A and B O has neither A nor B • • A has type B antibodies B has type A antibodies O has both A and B antibodies AB has neither A nor B antibodies

4 Basic Blood Types • Antigens also called agglutinogens • Antibodies called agglutinins Figure 19– 6 a

Blood type questions • Which blood type is the best in emergency settings (hint: which type can be given to anyone? ) • Which blood type is the lucky one that can receive blood from any donor?

Cross-Reaction • If donor and recipient blood types not compatible: – Plasma antibody meets its specific surface antigen and blood will agglutinate (clot) and hemolyze (kill each other) – This is really bad….

Cross-Reaction Figure 19– 6 b

Blood typing procedures • 6 trays with three wells each Victim A Crime scene B Rh Suspect 2 A B Suspect 1 Rh Suspect 3 Rh A 6 Bottles of “blood” B A B Rh Suspect 4 Rh A B Rh 3 Bottles of antibodies

Blood Typing Procedures • For each well Place 1 -2 drops of blood from one bottle in all 3 wells – – – 1 -2 drops of crime scene in each of the three wells 1 -2 drops of victim in each of the three wells 1 -2 drops of suspect 1 in each of the three wells 1 -2 drops of suspect 2 in each of the three wells 1 -2 drops of suspect 3 in each of the three wells 1 -2 drops of suspect 4 in in each of the three wells • For each tray add: – 1 -3 drops of anti-A serum to one well and stir – 1 -3 drops of anti-B serum to one well and stir – 1 -3 drops of anti-Rh serum to one well and stir Look for clumping reaction

Blood type? • What is the blood type? x = clumping rxn. A X B Rh X • Next question: what antibodies does this person have in their blood?

Example of Determining Genotype – Punnett Square • Mom’s phenotype is group A, genotype AO • Dad’s phenotype is group B, genotype BO B O A AB 25% AO 25% (Group A) O BO 25% (Group B) OO 25% (Group O)

Group O • Approximately 45% of the population is group O. • No A or B antigens present, think of as “ 0” antigens present. • These individuals form potent anti-A and anti-B antibodies which circulate in the blood plasma at all times.

Group A • Approximately 40% of the population is group A. • No B antigens present. • These individuals form potent anti-B antibodies which circulate in the blood plasma at all times.

Group B • Approximately 11% of the population is group B. • No A antigens present. • These individuals form potent anti-A antibodies which circulate in the blood plasma at all times.

Group AB • Approximately 4% of the population is group AB. • Both A and B antigens present. • These individuals possess no ABO antibodies. • NOTE: This slide is in error as it only illustrates presence of one antigen not 2.