NOD1 and NOD2 expression and function in very preterm infant mononuclear cells

Area of Science:

• Immunology
• Neonatal Research
• Innate Immunity

Background:

• Nucleotide-binding oligomerization domain-containing receptors (NOD1 and NOD2) are key components of the innate immune system.
• Understanding NOD1 and NOD2 function in neonates is crucial for addressing their susceptibility to infections.

Purpose of the Study:

• To evaluate the expression and function of NOD1 and NOD2 in mononuclear cells of very preterm and full-term infants.
• To determine if impaired NOD signaling contributes to increased sepsis risk in preterm infants.

Main Methods:

• Quantitative PCR (qPCR) and flow cytometry were used to measure NOD1 and NOD2 gene and protein expression.
• Monocyte cytokine responses to NOD agonists were assessed using multiplex immunoassay (Bioplex).

Main Results:

• NOD1 and NOD2 were expressed across various mononuclear cells, with highest levels in classical and intermediate monocytes.
• Monocyte NOD1 and NOD2 expression and function were comparable between very preterm infants, term infants, and adults.
• Induced cytokine production (TNFα, IL-6, IL-1β) by NOD activation was similar across all infant and adult groups.

Conclusions:

• Monocyte expression and function of NOD1 and NOD2 are intact in very preterm infants, similar to term infants and adults.
• Functional deficiencies in monocyte NOD signaling pathways are unlikely to be a factor in the heightened susceptibility to bacterial sepsis observed in preterm infants.