PRISM – PReterm Infant Skin Microbiome development and eubiosis

• Applicant: Dr. Janina Marißen
• Subject Area: Clinical Infectiology and Tropical Medicine
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 574129606

Bacterial infections are the second most common cause of death in preterm infants and are associated with significant short- and long-term health impairment. The immature skin of preterm infants is highly vulnerable, making it particularly susceptible to injury and infection. Protecting preterm skin with emollients has been defined as a top research priority by both the WHO and parent advocacy groups. However, the skin microbiome, potential confounding factors, and its immunological interplay with antimicrobial peptides have not been studied thoroughly in this population - at least in part due to methodological challenges related to low-biomass samples. A deeper understanding of the physiological development of the skin microbiome and relevant clinical confounders is urgently needed. This knowledge can form the basis for developing targeted preventive and therapeutic strategies, such as investigating mechanistic effects of emollients. With the proposed project, we aim to (a) characterize the physiological development of the skin microbiome in a well-defined cohort of preterm infants, (b) identify and define “eubiotic” and “dysbiotic” features, and (c) correlate levels of antimicrobial peptides with skin microbiome signatures. We will use preterm skin swab samples from a longitudinal single-center clinical study – the IRoN cohort – as well as samples from a longitudinal term-born cohort – the MIAI cohort (→WP1). Through metagenomic sequencing, we will be able to detect microbial signatures at the strain level and characterize the physiological development of the skin microbiome (→WP2). Our detailed database on ante- and postnatal parameters will enable deep clinical phenotyping and bioinformatical deconfounding. In collaboration with our long-standing partners, we aim to develop a eubiosis modeling score for the skin microbiome utilizing publicly available metagenomic data from existing studies. This will allow us to define states of skin eubiosis und dysbiosis within our own study populations (→WP3). In an exploratory approach, we will further investigate the correlation between antimicrobial peptide levels – specifically psoriasin and RNase 7 – with microbiome signatures, to elucidate potential mutual interactions (→WP4). Through these approaches, we aim to establish new targets for larger-scale, multicenter studies and to develop new strategies to protect this vulnerable population of preterm infants.

• DFG Programme: Research Grants