RESUMEN
OBJECTIVE: To investigate secretor gene fucosyltransferase 2 (FUT2) polymorphism and secretor phenotype in relation to outcomes of prematurity. STUDY DESIGN: Study infants were ≤32 weeks gestational age. Secretor genotype was determined from salivary DNA. Secretor phenotype was measured with H antigen, the carbohydrate produced by secretor gene enzymes, in saliva samples collected on day 9 ± 5. The optimal predictive cutoff point in salivary H values was identified with Classification and Regression Tree analysis. Study outcomes were death, necrotizing enterocolitis (NEC, Bell's stage II/III), and confirmed sepsis. RESULTS: There were 410 study infants, 26 deaths, 30 cases of NEC, and 96 cases of sepsis. Analyzed by genotype, 13% of 95 infants who were non-secretors, 5% of 203 infants who were heterozygotes, and 2% of 96 infants who were secretor dominant died (P = .01). Analyzed by phenotype, 15% of 135 infants with low secretor phenotype died, compared with 2% of 248 infants with high secretor phenotype (predictive value = 76%, P < .001). Low secretor phenotype was associated (P < .05) with NEC, and non-secretor genotype was associated (P = .05) with gram negative sepsis. Secretor status remained significant after controlling for multiple clinical factors. CONCLUSIONS: Secretor genotype and phenotype may provide strong predictive biomarkers of adverse outcomes in premature infants.
Asunto(s)
ADN/genética , Fucosiltransferasas/genética , Recien Nacido Prematuro , Polimorfismo Genético , Causas de Muerte/tendencias , Enterocolitis Necrotizante/enzimología , Enterocolitis Necrotizante/genética , Enterocolitis Necrotizante/mortalidad , Estudios de Seguimiento , Fucosiltransferasas/metabolismo , Genotipo , Humanos , Mortalidad Infantil/tendencias , Recién Nacido , Ohio/epidemiología , Pronóstico , Estudios Retrospectivos , Saliva/enzimología , Galactósido 2-alfa-L-FucosiltransferasaRESUMEN
Noroviruses (NVs) recognize human histo-blood group antigens (HBGAs) as receptors. We characterized the interaction of human milk samples with recombinant virus-like particles representing VA387, Norwalk, VA207, and MOH. Milk samples from 60 healthy women were tested for human HBGAs and for their ability to block the binding of NVs. Fifty-four women were secretors (Se+), and 6 were nonsecretors (Se-). No women had detectable A or B antigens in their milk samples. All 54 Se+ milk samples, but 0 of 6 Se- milk samples, blocked VA387 and Norwalk virus (Se+ binders) from binding to saliva samples. All 6 Lewis-positive Se- milk samples blocked binding to VA207, and variable blocking activities were exhibited by the Se+ milk samples. No milk samples blocked the binding of MOH to A and B antigens. Secretor and Lewis, but not A or B antigens, were present in human milk and were responsible for blocking NV binding to receptors and therefore are likely to be decoy receptors that protect breast-fed infants from NV infection.