Components of the lectin pathway of complement activation in paediatric patients of intensive care units
IMMUNOBIOLOGY
Authors: Swierzko, Anna S.; Szala-Poidziej, Agnieszka; Kilpatrick, David C.; Sobochiski, Michat; Chojnacka, Karolina; Sokolowska, Anna; Michalski, Mateusz; Mazerant, Karolina; Jensenius, Jens C.; Matsushita, Misao; Krajewski, Wojciech R.; Szczapa, Jerzy; Bak-Romaniszyn, Leokadia; Zeman, Krzysztof; Cedzynski, Maciej
Abstract
Infections are a major cause of childhood mortality. We investigated components of the lectin pathway of complement activation in the context of sepsis at both genetic and protein levels in neonates, infants and older children. Major components of the lectin pathway and two genes for Toll-like receptors were studied in 87 neonates with confirmed sepsis and compared with 40 babies with infections who did not develop sepsis (disease controls) and 273 infection-free neonatal controls. A second cohort comprised 47 older children with sepsis and 87 controls. Low MBL-conferring genotypes (LXA/O+O/O) were more frequent in sepsis patients than in healthy controls but no significant differences in the frequency of SNPs of other lectin pathway genes (FCN1, FCN2, FCN3, MASP1/3, MASP2) or TLR receptor genes (TLR2, TLR4) were found. One case of primary MASP-2 deficiency was found among healthy pre-terms and one neonate suffering from SIRS was heterozygous for the rare FCN1 gene mutation, +6658 G > A. Generally, sepsis was associated with low serum MBL and low ficolin-2 concentrations on admission. Among neonates, ficolin-1 and MASP-2 levels were elevated in sepsis relative to healthy, but not disease, controls. Unlike neonates, ficolin-3 and MASP-2 levels were lower in older patients than in healthy controls while no difference was found for ficolin-1. With the possible exception of MBL, inherited lectin pathway insufficiencies do not seem to predispose to sepsis, rather changes in protein concentrations reflect alterations in disease course. (C) 2016 Elsevier GmbH. All rights reserved.
H-ficolin (ficolin-3) concentrations and FCN3 gene polymorphism in neonates
IMMUNOBIOLOGY
Authors: Michalski, Mateusz; Szala, Agnieszka; St Swierzko, Anna; Lukasiewicz, Jolanta; Maciejewska, Anna; Kilpatrick, David C.; Matsushita, Misao; Domzalska-Popadiuk, Iwona; Borkowska-Klos, Monika; Sokolowska, Anna; Szczapa, Jerzy; Lugowski, Czeslaw; Cedzynski, Maciej
Abstract
Serum H-ficolin (ficolin-3) concentrations (n = 613) and FCN3 genotypes (n = 529) from a large group of neonates are presented. Both pre-term deliveries and low birthweight (independently of gestational age) were significantly associated with low H-ficolin concentrations but not with heterozygosity for the FCN3 1637delC frameshift mutation. The presence of the variant allele, however, apparently influenced the protein level. No association of FCN3 gene heterozygosity or relative functional H-ficolin insufficiency (determined as serum level <= 8.6 mu g/ml) with perinatal infections was found. One premature newborn, with confirmed infection caused by Streptococcus agalactiae, was H-ficolin-deficient (FCN3 variant homozygote, no detectable protein). We present what is only the fourth case report of total H-ficolin deficiency in the world literature. This neonate was however previously found to be mannan-binding lectin (MBL) as well as MBL-associated serine protease-2 (MASP-2) deficient and also had low serum L-ficolin. (C) 2011 Elsevier GmbH. All rights reserved.