title: A hemolytic anti-LKE associated with a rare LKE-negative, "weak P" red blood cell phenotype: alloanti-LKE and alloanti-P recognize galactosylgloboside and monosialogalactosylgloboside (LKE) antigens.
abstract: BACKGROUND
  "Weak P" is a rare red blood cell (RBC) phenotype, characterized by a global decrease in P(k) and P antigens. We now describe a second weak P individual who also typed LKE-negative (LKE-N) and possessed a clinically significant anti-LKE.
  
  
  METHODS
  Patient RBCs and plasma were examined by standard serology and flow cytometry. Glycosphingolipids (GSLs) from patient, P(k) , and LKE-strong (LKE-S) RBCs were isolated and analyzed by high-performance thin-layer chromatography (HPTLC). To confirm antibody specificity, patient serum and 30 human polyclonal controls, including alloanti-P and anti-PP1 P(k) , were tested against a panel of GSLs by HPTLC immunostaining.
  
  
  RESULTS
  The patient typed P1 +, P+, and LKE-N and possessed a "P-like" panagglutinin. In a two-stage indirect antiglobulin test, the patient's plasma caused hemolysis of LKE-S cells but not p, P(k) , or LKE-N cells. Clinically, transfusion of P+ RBCs compatible by a prewarmed technique had shortened RBC survival with laboratory evidence of hemolysis. Analysis of the patient's isolated RBC GSLs showed a 30% relative decrease in Gb3 (P(k) ) and Gb4 (P) and a 90% decrease in monosialogalactosylgloboside (MSGG, LKE), accompanied by increased lactosylceramide (CDH), paragloboside, and GM3. On HPTLC immunostaining, the patient's plasma strongly bound MSSG with weak binding to galactosylgloboside (Gb5). Binding to MSGG, Gb5, and Gb4 was also observed with some examples of alloanti-P from P(k) individuals, but not anti-PP1 P(k) , autoanti-P, or normal controls.
  
  
  CONCLUSIONS
  We describe the first example of a clinically significant anti-LKE in the setting of a rare weak P background. Human alloanti-LKE and some alloanti-P recognized Gb5 and MSGG.
authors.affiliation: Department of Pathology, University of Michigan, Ann Arbor, Michigan.
authors.forename: Laura
authors.initials: L
authors.lastname: Cooling
authors.forename: Louann R
authors.initials: LR
authors.lastname: Dake
authors.forename: Donna
authors.initials: D
authors.lastname: Haverty
authors.forename: Nancy
authors.initials: N
authors.lastname: Mullis
authors.forename: Susie
authors.initials: S
authors.lastname: Ellis
authors.forename: James
authors.initials: J
authors.lastname: Shayman
authors.forename: W John
authors.initials: WJ
authors.lastname: Judd
mesh_terms: D000744:Anemia, Hemolytic, Autoimmune / Q000097:blood* / Q000175:diagnosis / Q000235:genetics / Q000276:immunology; D000918:Antibody Specificity; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001788:Blood Grouping and Crossmatching / Q000379:methods; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D003298:Coombs Test; D017707:Erythrocyte Transfusion; D017809:Fatal Outcome; D005915:Globosides / Q000276:immunology*; D006028:Glycosphingolipids / Q000276:immunology*; D006801:Humans; D007518:Isoantibodies / Q000276:immunology*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D010127:P Blood-Group System / Q000276:immunology*; D010641:Phenotype; D055746:Stage-Specific Embryonic Antigens / Q000737:chemistry / Q000276:immunology*; D065227:Transfusion Reaction / Q000209:etiology
chemical_list: D005915:Globosides; D006028:Glycosphingolipids; D007518:Isoantibodies; D010127:P Blood-Group System; D055746:Stage-Specific Embryonic Antigens; C066584:stage-specific embryonic antigen-4