title: Inverse expression of P(k) and Luke blood group antigens on human RBCs.
abstract: BACKGROUND
  Luke (LKE) is a high-frequency RBC antigen, related to the P blood group system. A LKE-negative phenotype is found in 1 to 2 percent of donors and may be associated with increased P(k). Because P(k) and similar glycolipids are receptors for shiga toxin on cell membranes, a LKE-negative phenotype could have implications for infections by Shigella dysenteriae and enterohemorrhagic Escherichia coli.
  
  
  METHODS
  Volunteer donors (n = 257) were serologically typed for LKE with a LKE MoAb, MC813-70. LKE-strong-positive, LKE-weak-positive and LKE-negative RBCs were analyzed for P(k), P, LKE, and shiga toxin binding by immunofluorescence flow cytometry, high-performance thin-layer chromatography, scanning densitometry, and high-performance thin-layer chromatography immunostaining.
  
  
  RESULTS
  Among Iowa donors, 78.6 percent were LKE-strong-positive, 20.2 percent were LKE-weak-positive, and 1.2 percent were LKE-negative. There was an inverse expression of P(k) and LKE on RBCs. P(k) expression was increased on LKE-negative RBCs and was associated with increased shiga toxin binding. A LKE-active glycolipid was identified in the ganglioside fraction of LKE-strong-positive RBCs.
  
  
  CONCLUSIONS
  A LKE-negative phenotype is associated with increased expression of P(k) on RBCs. Differences in P(k) and LKE expression may play a role in host susceptibility to infection with S. dysenteriae and E. coli.
authors.affiliation: Department of Pathology, University of Michigan Medical School, University Hospital Box 0054, 1500 East Medical Center Drive, Ann Arbor, MI 48109, USA. lcooling@med.umich.edu
authors.forename: L L
authors.initials: LL
authors.lastname: Cooling
authors.forename: K
authors.initials: K
authors.lastname: Kelly
mesh_terms: D001782:Blood Donors; D001789:Blood Group Antigens / Q000276:immunology*; D004912:Erythrocytes / Q000737:chemistry / Q000276:immunology*; D006017:Glycolipids / Q000737:chemistry; D006028:Glycosphingolipids / Q000097:blood*; D006801:Humans; D007484:Iowa; D007519:Isoantigens / Q000097:blood; D010127:P Blood-Group System / Q000276:immunology*; D010641:Phenotype; D022621:Shiga Toxin / Q000378:metabolism; D055746:Stage-Specific Embryonic Antigens
chemical_list: D001789:Blood Group Antigens; D006017:Glycolipids; D006028:Glycosphingolipids; D007519:Isoantigens; D010127:P Blood-Group System; D055746:Stage-Specific Embryonic Antigens; C066584:stage-specific embryonic antigen-4; D022621:Shiga Toxin