Healthy preterm newborns: Altered innate immunity and impaired monocyte function

Area of Science:

• Immunology
• Neonatal Research
• Infectious Disease

Background:

• Neonatal immunity is immature, increasing preterm (PT) infants' infection risk.
• Monocytes and inflammasomes are crucial in early immune responses.
• Limited data exists on innate immune profiles in PT versus full-term infants.

Purpose of the Study:

• To investigate differences in innate immune cell profiles, gene expression, and plasma cytokines between PT and full-term infants.
• To explore potential links between immune alterations and infection susceptibility in PT newborns.

Main Methods:

• High-dimensional flow cytometry to analyze monocyte and NK cell populations.
• Gene expression analysis of inflammasome activation.
• Plasma cytokine quantification, including alarmin S100A8 levels.
• Study cohort: 68 healthy PT and full-term infants.

Main Results:

• PT infants exhibited higher CD56+/- CD16+ NK cells and immature monocytes.
• Lower proportions of classical monocytes were observed in PT infants.
• Reduced inflammasome activation post-monocyte stimulation and elevated S100A8 plasma levels were noted in PT infants.

Conclusions:

• PT newborns possess altered innate immunity, characterized by monocyte functional impairment.
• A pro-inflammatory plasma profile in PT infants may contribute to increased infectious disease susceptibility.
• Findings suggest potential targets for novel therapeutic strategies and clinical interventions in preterm neonates.