title: Diminished cord blood lymphocyte L-selectin expression in neonatal bacterial infection.
abstract: L-Selectin, a leukocyte surface glycoprotein involved in white blood cell extravasation, is rapidly down-regulated after leukocyte activation. We prospectively determined lymphocyte L-selectin expression in freshly obtained cord blood samples of 98 neonates (gestational age 25-42 weeks). In eight infants with bacterial infection, the mean percentage of L-selectin(high) lymphocytes was 32.5% (SD 20.1%), compared to 60.1% (SD 18.7%) in the control group (P < 0.01). A percentage of L-selectin(high) lymphocytes of less than 42% had a sensitivity of 75% and a specificity of 82% in identifying infected newborns. Cord blood lymphocyte L-selectin expression was independent of gestational age, birth weight, umbilical artery pH, hematocrit, white blood cell count, absolute neutrophil count, C-reactive protein level, or maternal fever before delivery while there was a weak correlation with the newborn's immature/total ratio and platelet count. To our knowledge, this is the first report demonstrating downregulation of human lymphocyte L-selectin expression following activation of the immune system in vivo.
authors.affiliation: Department of Neonatology, Children's Hospital, Rudolf Virchow Medical Center, Berlin Free University, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Bührer
authors.forename: U
authors.initials: U
authors.lastname: Luxenburger
authors.forename: B
authors.initials: B
authors.lastname: Metze
authors.forename: E
authors.initials: E
authors.lastname: Kattner
authors.forename: G
authors.initials: G
authors.lastname: Henze
authors.forename: J W
authors.initials: JW
authors.lastname: Dudenhausen
authors.forename: M
authors.initials: M
authors.lastname: Obladen
mesh_terms: D015815:Cell Adhesion Molecules / Q000097:blood*; D004927:Escherichia coli Infections / Q000097:blood*; D005312:Fetal Blood / Q000382:microbiology*; D006801:Humans; D007231:Infant, Newborn; D019041:L-Selectin; D007958:Leukocyte Count; D008562:Membrane Glycoproteins / Q000097:blood*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013290:Streptococcal Infections / Q000097:blood*
chemical_list: D015815:Cell Adhesion Molecules; D008562:Membrane Glycoproteins; D019041:L-Selectin