<abstract xmlns="http://www.w3.org/1999/xhtml">The antigens in the P1PK blood group system are carried on glycosphingolipids. The system currently includes three different antigens, P1, Pk, and NOR. The P1 antigen was disovered in 1927 by Landsteiner and Levine, and Pkand NOR were described in 1951 and 1982, respectively. As in the ABO system, naturally occurring antibodies of the immunoglobulin (Ig) M or IgG class, against the missing carbohydrate structures, can be present in the sera of people lacking the corresponding antigen. Anti-P1 is generally a weak and cold-reactive antibody not implicated in hemolytic transfusion reaction (HTR) or hemolytic disease of the fetus and newborn while Pkantibodies can cause HTR, and anti-NOR is regarded as a polyagglutinin. A higher frequency of miscarriage is seen in women with the rare phenotypes p, P1k, and P2k. Furthermore, the Pkand P1 antigens have wide tissue distributions and can act as host receptors for various pathogens and toxins. Why p individuals lack not only Pkand P expression but also P1 has been a longstanding enigma. Recently, it was shown that the same <italic>A4GALT-</italic>encoded galactosyltransferase synthesizes both the P1 and Pkantigens and that a polymorphism in a new exon in this gene predicts the P1and P2phenotypes. <italic><bold>Immunohematology</bold></italic><bold>2013;29:25–33.</bold></abstract>

The antigens in the P1PK blood group system are carried on glycosphingolipids. The system currently includes three different antigens, P1, Pk, and NOR. The P1 antigen was disovered in 1927 by Landsteiner and Levine, and Pkand NOR were described in 1951 and 1982, respectively. As in the ABO system, naturally occurring antibodies of the immunoglobulin (Ig) M or IgG class, against the missing carbohydrate structures, can be present in the sera of people lacking the corresponding antigen. Anti-P1 is generally a weak and cold-reactive antibody not implicated in hemolytic transfusion reaction (HTR) or hemolytic disease of the fetus and newborn while Pkantibodies can cause HTR, and anti-NOR is regarded as a polyagglutinin. A higher frequency of miscarriage is seen in women with the rare phenotypes p, P1k, and P2k. Furthermore, the Pkand P1 antigens have wide tissue distributions and can act as host receptors for various pathogens and toxins. Why p individuals lack not only Pkand P expression but also P1 has been a longstanding enigma. Recently, it was shown that the same A4GALT-encoded galactosyltransferase synthesizes both the P1 and Pkantigens and that a polymorphism in a new exon in this gene predicts the P1and P2phenotypes. Immunohematology2013;29:25–33.

P1PK: The blood group system that changed its name and expanded

Department of Clinical Immunology and Transfusion Medicine

Immunohematology

{"article-title":"P1PK: The blood group system that changed its name and expanded"}

The antigens in the P1PK blood group system are carried on glycosphingolipids. The system currently includes three different antigens, P1, Pk, and NOR. The P1...

P1PK: The blood group system that changed its name and expanded

Article Category: Review

Published Online: Dec 01, 2019

Page range: 25 - 33

DOI: https://doi.org/10.21307/immunohematology-2019-120

© 2013 Å. Hellberg, et al., published by Sciendo