Antibodies produced against Kell antigens

Antibody type IgG
IgM is uncommon
Antibody reactivity Does not bind complement
If hemolysis does occur, it is extravascular in nature.
Transfusion reaction Can cause a severe hemolytic transfusion reaction
Anti-K and anti-Ku are capable of causing a severe reaction. A milder reaction is caused by anti-k, anti-Kpa, anti-Kpb, anti-Jsa, and anti-Jsb.
Hemolytic disease of the newborn Can cause severe fetal anemia
Kell isoimmunization is the third most common cause of HDN after Rh and ABO. Anti-Kell causes severe fetal anemia by suppressing fetal RBC synthesis (3, 4).

From: Chapter 8, The Kell blood group

Cover of Blood Groups and Red Cell Antigens
Blood Groups and Red Cell Antigens [Internet].
Dean L.
Bethesda (MD): National Center for Biotechnology Information (US); 2005.

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