Elevated Levels of Lipopolysaccharide-Binding Protein and Soluble CD14 in Plasma in Neonatal Early-Onset Sepsis

No data on lipopolysaccharide-binding protein (LBP) in newborns with sepsis have been available up to now. We therefore determined levels of LBP and soluble CD14 (sCD14) in plasma of healthy and septic neonates in order to evaluate their potential diagnostic role. The study included prospectively collected patient samples of two recently published studies on cytokine expression in neonatal sepsis. Twenty-nine septic patients were enrolled in the present analysis. Samples—either cord blood or peripheral blood—from patients admitted within the first 24 h of life for suspicion of sepsis and cord blood samples of a control group of 40 healthy mature infants delivered spontaneously were analyzed. For seven patients of the septic group, a second sample collected between 24 and 48 h of life was available. Levels of sCD14 and LBP in plasma were determined by an enzyme immunoassay using recombinant CD14 and LBP as standards. LBP and sCD14 were correlated to cytokine plasma levels. In septic neonates, LBP (median, 36.6 versus 7.8 μg/ml; P < 0.001) and sCD14 (median, 0.42 versus 0.28 μg/ml; P < 0.001) levels were highly elevated when compared to those of healthy neonates and strongly correlated to granulocyte colony-stimulating factor (G-CSF), interleukin-1β (IL-1β), IL-6, and IL-8 levels. LBP levels in septic neonates analyzed between 24 and 48 h of life even increased when compared to samples obtained at or shortly after delivery (median, 36.6 versus 60 μg/ml; P = 0.038). In summary, levels of LBP in plasma of neonates with early-onset sepsis are significantly elevated; the elevated plasma levels seem to persist for more than 24 h, which could provide the clinician with a prolonged time period to identify the newborn with bacterial sepsis

Characterization of the human neutrophil alloantigen-3a

Transfusion-related acute lung injury (TRALI) is a frequent cause of transfusion-associated morbidity and mortality. Severe TRALI is often due to antibodies in blood components directed against the human neutrophil alloantigen-3a (HNA-3a). We show here that the HNA-3a antigen arises from a nucleotide polymorphism in the choline transporter-like protein-2 gene (SLC44A2), with the resulting variation at amino acid position 154 determining the reactivity of the protein with HNA-3a-specific antibodies; the variant with an arginine at this position, rather than a glutamine, constitutes the HNA-3a antigen. The molecular identification of this antigen should facilitate the development of assays for blood donor screening to lower the risk of TRALI

Novel Mutation in Bernard-Soulier Syndrome

Background: Bernard-Soulier syndrome (BSS) is a severe congenital bleeding disorder characterized by thrombocytopenia, thrombocytopathy and decreased platelet adhesion. BSS results from genetic alterations of the glycoprotein (GP) Ib/IX/V complex. Methods: We report on a patient demonstrating typical BSS phenotype (thrombocytopenia with giant platelets, bleeding symptoms). However, BSS was not diagnosed until he reached the age of 39 years. Results: Flow cytometry of the patient’s platelets revealed absence of GPIb/IX/V receptor surface expression. In addition, immunofluorescence analysis of patient’s platelets demonstrated very faint staining of GPIX. A novel homozygous deletion comprising 11 nucleotides starting at position 1644 of the GPIX gene was identified using molecular genetic analysis. Conclusions: The novel 11-nucleotide deletion (g.1644_1654del11) was identified as causing the bleeding disorder in the BSS patient. This homozygous deletion includes the last 4 nucleotides of the Kozak sequence as well as the start codon and the following 4 nucleotides of the coding sequence. The Kozak sequence is a region indispensable for the initiation of the protein translation process, thus preventing synthesis of functional GPIX protein in the case of deletion.Hintergrund: Das Bernard-Soulier-Syndrom (BSS) ist eine angeborene Blutungsstörung, die mit Thrombozytopenie, Thrombozytopathie und verminderter Thrombozytenadhäsion assoziiert ist. BSS wird durch genetische Veränderungen des Glykoprotein(GP)-Ib/IX/V-Komplexes verursacht. Methoden: Wir berichten über einen Patienten mit typischem BSS-Phänotyp (Thrombozytopenie mit Riesenthrombozyten, Blutungssymptome). Dennoch wurde die Diagnose BSS erst im Alter von 39 Jahren gestellt. Ergebnisse: Die Durchflusszytometrie der Thrombozyten des Patienten ergab eine fehlende Oberflächenexpression des GPIb/IX/V-Rezeptors. Zusätzlich zeigten Immunfluoreszenz-Analysen der Thrombozyten eine nur sehr schwache Anfärbung von GPIX. In der molekulargenetischen Analyse wurde eine noch nicht bekannte homozygote Deletion von 11 Nukleotiden (beginnend an Position 1644 im GPIX-Gen) identifiziert. Schlussfolgerungen: Diese neue Deletion von 11 Nukleotiden (g.1644_1654del11) wurde als Ursache für die vermehrte Blutungsneigung bei dem BSS-Patienten identifiziert. Von der homozygoten Deletion betroffen sind die letzten 4 Nukleotide der Kozak-Sequenz sowie das Startkodon und weitere 4 Nukleotide des kodierenden Bereichs. Die Kozak-Sequenz ist unerlässlich für die Initiation der Translation in der Proteinbiosynthese, so dass die bei dem Patienten nachgewiesene Deletion die Synthese des funktionellen GPIX-Proteins verhindert.Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich