Wade, W. G. | Search bioRxiv

bioRxiv2019

Perinatal Inflammation Influences but Does Not Arrest Rapid Immune Development in Preterm Babies

Infection and infection-related complications are important causes of death and morbidity following preterm birth. Despite this, there is limited understanding of the development of the immune system in those born prematurely and how it is influenced by perinatal factors. To investigate this, we prospectively and longitudinally followed a cohort of babies born before 32 weeks of gestation. We demonstrated that preterm babies, including those born extremely prematurely, were capable of rapidly acquiring adult levels of immune functionality; that immune maturation appeared to occur independently of the developing microbiome, which was highly heterogeneous across different infants; and that the biggest drivers of change in the trajectory of perinatal immune development was exposure to infection in utero or post-natally. Conspicuously, a unifying factor among infants who developed infection despite their growing immune potentials was an inability to mount adequate T cell CXCL8 responses. Because this defect was present at birth, it may predict those babies likely to have poor clinical outcomes.

immunology↗

bioRxiv2018

Streptococcus salivarius - a potential salivary biomarker for orofacial granulomatosis and Crohn’s disease?

ObjectiveOrofacial granulomatosis (OFG) is a rare disease characterised by chronic, non-caseating, granulomatous inflammation primarily affecting the oral cavity. Histologically, it is similar to Crohns disease (CD) and a proportion of patients have both OFG and CD. The cause of OFG remains elusive but it has been suggested that microbial interactions may be involved. The aim of this study was to compare the salivary microbial composition of subjects with OFG and/or CD and healthy controls.\n\nDesign261 subjects were recruited, of whom 78 had OFG only, 40 had both OFG and CD, 97 had CD only with no oral symptoms and 46 were healthy controls. Bacterial community profiles were obtained by sequencing the V1-V3 region of the 16S rRNA gene.\n\nResultsThere were no differences in richness or diversity of the salivary bacterial communities between patient groups and controls. The relative abundance of the Streptococcus salivarius-group were raised in patients with OFG or CD only compared to controls while that of the Streptococcus mitis -group was lower in CD compared to both OFG and controls. One S. salivarius oligotype made the major contribution to the increased proportions seen in patients with OFG and CD.\n\nConclusionThe salivary microbiome of individuals with OFG and CD was similar to that found in health although the proportions of S. salivarius, a common oral Streptococcus were raised. One specific strain-level oligotype was found to be primarily responsible for the increased levels seen.

microbiology↗