Early response in neonatal septicemia. The effect of Escherichia coli, Streptococcus agalactiae and tumor necrosis factor on the generation of lactoferrin

Abstract

response in neonatal septicemia. The effect of Escherichia coli, Streptococcus agalactiae and tumor necrosis factor on the generation of lactofemn. APMIS Using an in v i m model, we report the early effect of Escherichia coli (E. coli), Streptococcus agalactiea (group B streptococci, GBS) and recombinant tumor necrosis factor alpha (TNF) on the release of lactofenin (LF) and the generation of interleukin-1 (IL-I) due to E. coli, using heparinized whole blood from healthy full-term newborns. We wanted to find a dose response relationship between lactofemn generation on the one hand and the amount of E. coli, GBS and TNF on the other hand. In a final concentration of lo7 per ml both bacteria increased the release of LF significantly. The response to E. coli was immediate and increased during the subsequent 20 minutes (mean f S.D.: control 0.66 mg/l f 0.29 mg/l, E. coli 1.83 mg/l f 0.76 mg/l, p < 0.00 1). GBS was a less potent stimulant than E. coli and the response was only apparent after 20 minutes (mean k S.D.: 1.06 mg/l f 0.49 mg/l, p < 0.01). TNF in a concentration of 10000 pg/ml as well as loo0 pg/ml increased the release of LF significantly (after 20 minutes mean k S.D.: 1.09 mg/l f 0.42 mg/l and 0.97 mg/l f 0.36 mg/l, respectively), whereas a concentration of 100 pg/ml had no effect. Whole blood incubated with different preparations of LF for 20 minutes did not increase the generation of LF significantly. No significant changes in IL-1 levels were observed. Lactofemn had bacteriostatic but no bactericidal effect on GBS and Streptococcus mutans.

Group B Streptococcus Induces Neutrophil Recruitment to Gestational Tissues and Elaboration of Extracellular Traps and Nutritional Immunity

“…Lactoferrin is of particular interest as GBS induces elevated lactoferrin levels during infection of placental membranes, however the cellular contribution for this was obscure (Boldenow et al, 2013 ). Furthermore, elevated lactoferrin levels have been associated with GBS infection in neonates such as septicemia (Gutteberg et al, 1990 , 1991 ). We report that GBS-induced NETs are a source of lactoferrin, however the role of these structures and antimicrobial molecules in the context of infection during pregnancy remains unknown.…”

Early detection of neonatal group B streptococcus sepsis and the possible diagnostic utility of IL-6, IL-8, and CD11b in a human umbilical cord blood in vitro model

“…In a dose–response assessment, HUCB was stimulated for 2 hours with GBS at concentrations of 10 3 , 10 5 , 10 6 , 5×10 6 , 10 7 , 5×10 7 , 10 8 , or 5×10 8 cells/mL, which we, in consultation with clinical and academic microbiologists in our institution, thought would cover relevant GBS concentrations for clinical sepsis ( Figure 1 ). 20 The surface expression of CD11b increased in a dose-dependent manner and plateaued at 5×10 7 GBS cells/mL and IL-8 at 5×10 6 GBS cells/mL. TLR2 on monocytes and CD64 on granulocytes continued to increase at a concentration of 5×10 8 GBS cells/mL.…”

Lactoferrin confidential: ancient actor starring in new role?

“…Lf was first discovered in milk in 1939 (3), and was subsequently found in tears, salvia, and secretions from the biliary tract (4). Lf is released from neutrophil leukocytes when triggered by bacteria or cytokines and rises rapidly in blood during the early phase of bacterial infections (5–8). The protective effects of Lf range from direct antimicrobial activities against a large panel of microorganisms, including bacteria, viruses, fungi, and parasites, to anti‐inflammatory and possibly anticancer activities.…”