title: Preterm and term neonates transplacentally acquire IgG antibodies specific to LPS from Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa.
abstract: High incidences of Gram-negative bacteria are found in neonatal nosocomial infections. Our aim was to investigate placental transmission of immunoglobulin G (IgG) reactive with lipopolysaccharide from Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli O111, O6 and O26. The total and lipopolysaccharide-specific IgM and IgG were determined in 11 maternal/umbilical-cord sera aged ≤33 weeks (GI); 21 aged >33 and <37 weeks (GII); and 32 term newborns (GIII). The total and lipopolysaccharide-specific IgM concentrations were equivalent in maternal sera. The total IgG concentrations were equivalent in maternal and newborn sera, with the exception of GIII newborns as compared with their mothers (P<0.0001) and with neonates from GI and GII (P<0.05). Lipopolysaccharide-specific IgG concentrations were lower in GI neonates than in their mothers (P<0.01) and lower in GII (P<0.05). Lower lipopolysaccharide-specific IgG levels were observed among neonates only for O111 in GI (P<0.05) and for O26 and Pseudomonas in GII, both as compared with GIII (P<0.05). The anti-lipopolysaccharide IgG transfer ratios were lower in GI (except for O26) and in GII (except for Klebsiella and O111) as compared with GIII (P<0.05). Our results suggest that the greater susceptibility to infections in preterm infants is influenced (besides the humoral response) by factors intrinsic and extrinsic to the condition of prematurity.
authors.affiliation: Department of Parasitology, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brazil. anmarques@usp.br
authors.forename: Ana Lúcia
authors.initials: AL
authors.lastname: Silveira Lessa
authors.forename: Vera Lúcia Jornada
authors.initials: VL
authors.lastname: Krebs
authors.forename: Tatiana Braga
authors.initials: TB
authors.lastname: Brasil
authors.forename: Gerlândia Neres
authors.initials: GN
authors.lastname: Pontes
authors.forename: Magda
authors.initials: M
authors.lastname: Carneiro-Sampaio
authors.forename: Patricia
authors.initials: P
authors.lastname: Palmeira
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D004926:Escherichia coli / Q000276:immunology*; D005260:Female; D006801:Humans; D007112:Immunity, Maternally-Acquired; D007074:Immunoglobulin G / Q000097:blood*; D007075:Immunoglobulin M / Q000097:blood; D007231:Infant, Newborn; D007711:Klebsiella pneumoniae / Q000276:immunology*; D008070:Lipopolysaccharides / Q000276:immunology*; D047928:Premature Birth; D011550:Pseudomonas aeruginosa / Q000276:immunology*; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D008070:Lipopolysaccharides