Lewis

Question 1

these are actually not made by the RBC - rather made by tissue cells and secreted into the plasma + other fluids where they adsorb onto the RBC membrane

Answer 1

lewis antigens

• glycoproteins in secretions
• glycolipids on RBCs

Question 2

three genes interact with one another giving rise to Lewis antigens found in plasma and on RBCs

Answer 2

H (fut-1)
Se (fut-2)
Le (fut-3)

Question 3

Lewis antibodies

Answer 3

• IgM
• naturally occurring
• clinically insignificant
• tend to be a nuisance; could mask clinically significant Abs
• most often produced by Le (a-b-)
• good binders of complement - C9 invitro
• enhanced by enzymes
• blood bank not required to obtain antigen neg blood if antibody does not react at 37C *