7.1 Other Blood Groups

"Lewis antigens"

"Not intrinsic to RBCs; adsorbed from plasma onto the red cell membrane."

"Main Lewis antigens"

"Lea and Leb."

"Expression of Lewis antigens"

"Variable among individuals; may be absent in pregnant women."

"Chromosome of Lewis gene"

"Chromosome 19."

"Function of Le gene"

"Codes for fucosyltransferase enzyme."

"Anti-Lea and Anti-Leb"

"Naturally occurring IgM antibodies found in Le(a-b-) individuals."

"Secretor gene"

"FUT2 gene located on chromosome 19q13.3."

"Effect of Lewis antigens on disease"

"Leb antigen may facilitate H. pylori attachment

"Antibody type in Lewis system"

"Typically IgM

"Storage effect on Lewis antigens"

"Antigens may be lost from stored red cells."

"P1 antigen expression"

"Poorly expressed at birth; fully develops by 7 years of age."

"Source of P1-like substances"

"Found in hydatid cyst fluid and egg whites of turtledoves."

"Anti-P1 antibody"

"Naturally occurring IgM found in P2 individuals."

"Anti-PP1Pk (anti-Tja)"

"Found in p phenotype; associated with spontaneous abortions and tumor immunity."

"Anti-P antibody"

"Alloantibody found in Pk individuals; implicated in paroxysmal cold hemoglobinuria."

"Donath-Landsteiner Test"

"Used to confirm biphasic hemolysin activity of anti-P antibody."

"I and i antigens at birth"

"Infant RBCs rich in i; I increases with age."

"HEMPAS association"

"i antigen predominance in Hereditary Erythroblastic Multinucleation with Positive Acidified Serum."

"Anti-I antibody"

"Common autoantibody reacting with adult cells; not associated with HDFN."

"Pathologic Anti-I"

"IgM autoantibody causing hemolysis and Raynaud’s phenomenon."

"Stimulus for Autoanti-I"

"Mycoplasma pneumoniae or Listeria infection."

"Jka and Jkb expression"

"Well developed in neonates; Jka at 11 weeks

"Kidd antibodies"

"Common cause of delayed HTRs; difficult to detect."

"Enhancement of Kidd antibodies"

"Enhanced by enzymes like ficin or papain and media like PEG."

"JK null phenotype"

"Jk(a-b-) cells resistant to 2M urea lysis; no clinical abnormality."

"Kell system discovery"

"First identified in 1946 in Mrs. Kelleher."

"Kell antigens"

"Highly immunogenic; K is second only to D in immunogenicity."

"Kell antibody significance"

"Anti-K is common

"Enzyme effect on Kell antigens"

"Destroyed by DTT and ZZAP; resistant to ficin and papain."

"McLeod phenotype"

"X-linked Kell-null with chronic hemolytic anemia and neurologic symptoms."

"Duffy antigens"

"Fya and Fyb; associated with resistance to P. vivax malaria."

"Duffy null phenotype"

"Fy(a-b-) common in Africans; resistant to malaria."

"Anti-Fya and Anti-Fyb"

"IgG antibodies reacting at antiglobulin phase; show dosage effect."

"Fyx allele"

"Weak variant of Fyb allele; no distinct antigen."

"Fy3 antigen"

"Present whenever Fya or Fyb is present; absent in Fy(a-b-) individuals."

"Lutheran system discovery"

"Anti-Lua first identified in patient with lupus in 1945."

"Lutheran antigens"

"Poorly developed at birth; widely distributed in tissues."

"Lutheran null types"

"Includes Dominant (In(Lu))

"Anti-Lu3 antibody"

"Rare; reacts with all RBCs except those of Lu(a–b–) phenotype."

"Anti-Lua antibody"

"Naturally occurring IgM; room temperature reactivity with mixed field pattern."

"MNS antigens"

"Located on glycophorins A and B; include M

"Anti-M"

"Naturally occurring

"Anti-N"

"Cold-reactive IgM or IgG

"Anti-S and Anti-s"

"IgG antibodies; implicated in HDFN and HTRs."

"En(a–) phenotype"

"Null phenotype of MNS; lacks high-prevalence En antigen."

"Mk phenotype"

"Null phenotype from deletion of GYPA and GYPB genes; M–N–S–s–U–."

"Malaria and Duffy antigen"

"Fy(a–b–) RBCs resistant to Plasmodium vivax."

"McLeod syndrome"

"Includes hemolytic anemia

"Raynaud’s phenomenon"

"Vasospasm of small arteries

"Blood group allele expression"

"Most are codominant and express a corresponding antigen."

"Null phenotype"

"Results when both alleles at a locus are silent; no antigen expression."

"Use of null phenotype RBCs"

"Helpful for evaluating antibodies to high-prevalence antigens."

"Lewis system ISBT number"

"007"

"P blood group ISBT system"

"P1PK (003)

"P blood group founding"

"Described by Landsteiner and Levine in 1927."

"Luke antigen discovery"

"1965 by Tippett et al. in a Hodgkin’s lymphoma patient."

"Luke antigen phenotypes"

"84% Luke+

"P1 antigen degradation"

"Rapidly deteriorates on storage."

"Anti-P1 in disease"

"Seen in hydatid disease and parasitic infections like Clonorchis sinensis."

"Anti-PP1Pk origin"

"Originally Anti-Tja; first found in Mrs. Jay with gastric cancer."

"Anti-P antibody properties"

"Biphasic hemolysin; attaches in cold

"Biphasic hemolysis test"

"Donath-Landsteiner Test used to detect anti-P."

"Anti-Pk antibody"

"Found in P1 individuals with biliary cirrhosis or AIHA."

"i antigen persistence"

"Seen in rare adult individuals; associated with HEMPAS."

"Glycosylation defect in HEMPAS"

"Glycoproteins lack polylactosamines due to deficiency."

"Common interfering autoantibody in typing"

"Benign anti-I found in healthy individuals."

"Raynaud’s phenomenon mechanism"

"Vasospasm in response to cold or stress."

"JK3 antigen"

"Common antigen in Kidd system present when either Jka or Jkb is present."

"In(Jk) phenotype"

"Inhibitor of Kidd antigens not at Jk locus; dominant in Japanese families."

"Jk gene location"

"Chromosome 18q12.3; gene SLC14A1."

"Kell system ISBT number"

"006"

"Kell antigen detection in fetus"

"K: 10 weeks; k: 7 weeks."

"Kell antigen enzyme resistance"

"Unaffected by ficin/papain; destroyed by trypsin and DTT."

"Most immunogenic Kell antigen"

"K antigen; second only to D."

"Xk protein expression"

"Found in erythroid and non-erythroid tissues like brain and heart."

"Kell antigen removal method"

"Destroyed by glycine-acid EDTA and thiol reagents like DTT."

"Anti-K detection enhancement"

"PEG with indirect antiglobulin test."

"Symptoms of McLeod phenotype"

"Chronic anemia

"Age of McLeod syndrome onset"

"Typically between 40–50 years."

"Fy gene location"

"Chromosome 1q23.2

"Fy gene linkage"

"Syntenic but unlinked to Rh gene."

"DARC function"

"Duffy Antigen Receptor for Chemokines; binds inflammatory cytokines."

"Anti-Fy5"

"Reacts with Fy(a+) or Fy(b+) RBCs; not with Fy(a–b–) cells."

"Lu gene regulation"

"In(Lu) gene inhibits expression; linked to EKLF transcription factor."

"Lu(a-b-) dominant type"

"Expression suppressed by In(Lu); normal P1 and i antigens."

"Lu(a-b-) recessive type"

"Homozygous for rare LuLu alleles; can make anti-Lu3."

"Lu(a-b-) X-linked type"

"Inheritance suggests X-linked inhibitor (XS2 allele)."

"Lutheran antigens in tissue"

"Found in brain

"Lu antigens on protein"

"Located on type 1 transmembrane protein (B-CAM)."

"Anti-Lub"

"IgG or IgM; associated with shortened RBC survival

"Anti-Luab"

"Called anti-Lu3; reacts with all RBCs except Lu(a–b–)."

"MNS system history"

"Anti-M and anti-N first described in 1927 by Landsteiner and Levine."

"S and s antigen discovery"

"S in 1947

"U antigen discovery"

"1953; found on all S+s+ cells; high prevalence."

"GPA and GPB proteins"

"Carry MNS antigens; GPA for M/N

"Anti-M reactivity"

"pH-dependent IgM reacting below 37°C; does not bind complement."

"Anti-N in dialysis patients"

"Formed due to formaldehyde sterilization; called anti-Nf."

"Anti-S/s reactivity"

"IgG that binds complement; reacts at 37°C; causes HTR and HDFN."

"En(a–) phenotype origin"

"Named for 'envelope'; lacks high-prevalence antigen on GPA."

"Mk gene effect"

"Silent gene deleting GYPA and GYPB; produces M–N–S–s–U– RBCs."