Which statement about Lutheran antigens is true?

Which statement about Lutheran antigens is true?

• A. They are destroyed by enzymes
• B. They are not affected by enzymes
• C. They are expressed only on type O RBCs
• D. They are not clinically significant

Answer: (A)

Proteolytic enzyme sensitivity of red cell antigens is the key idea. Lutherian antigens, Lu^a and Lu^b, are carried by a membrane glycoprotein on red cells. When cells are treated with proteolytic enzymes such as papain or ficin, these membrane proteins are cleaved and the Lutheran antigens are destroyed. That means antibody testing using enzyme-treated cells will show loss of Lutheran antigen reactivity, which is why this statement is true. These antigens are not restricted to type O cells, so the claim that they’re expressed only on type O red cells isn’t correct. As for clinical significance, Lutheran antibodies can be clinically significant in some circumstances, though they are often not associated with severe reactions; stating they are never clinically significant isn’t accurate.

Proteolytic enzyme sensitivity of red cell antigens is the key idea. Lutherian antigens, Lu^a and Lu^b, are carried by a membrane glycoprotein on red cells. When cells are treated with proteolytic enzymes such as papain or ficin, these membrane proteins are cleaved and the Lutheran antigens are destroyed. That means antibody testing using enzyme-treated cells will show loss of Lutheran antigen reactivity, which is why this statement is true.

These antigens are not restricted to type O cells, so the claim that they’re expressed only on type O red cells isn’t correct. As for clinical significance, Lutheran antibodies can be clinically significant in some circumstances, though they are often not associated with severe reactions; stating they are never clinically significant isn’t accurate.