Beyond the Neutrophil Count: Functional Profiling and Targeted Modulation of Neutrophils in Paediatric Care

Area of Science:

• Pediatric Hematology
• Immunology
• Neonatology

Background:

• Neutrophils are the most abundant leukocytes in children, vital for innate immunity.
• Paediatric neutrophils have distinct effector profiles and regulatory roles compared to adults.
• Quantitative and qualitative neutrophil disturbances impact infection susceptibility and inflammatory injury in children.

Purpose of the Study:

• To review current understanding of neutrophil biology in key paediatric settings.
• To explore the role of neutrophils in paediatric sepsis, neutropenia, neonatal brain injury, and allergic diseases.
• To highlight distinct paediatric neutrophil functions and their implications for child health.

Main Methods:

• Literature review synthesizing current research on paediatric neutrophil biology.
• Analysis of data from neonatal, sepsis, and allergic cohorts.
• Examination of experimental and clinical data in neonatal brain injury and childhood neutropenia.

Main Results:

• Paediatric neutrophils show abnormal trafficking, immature forms, dysregulated signaling, and excessive NETosis in sepsis, impacting pathogen control and organ injury.
• Childhood neutropenia involves transient post-viral suppression or congenital defects, with G-CSF therapy improving survival in severe cases.
• Neutrophil recruitment in neonatal brain injury is biphasic, with initial damage and later reparative roles.
• Neutrophils are key in paediatric allergic diseases, with specific endotypes and pathways linked to severity and treatment response.

Conclusions:

• Paediatric neutrophils are central mediators in child health and disease, exhibiting unique characteristics.
• Understanding these distinct neutrophil roles is crucial for managing paediatric infections, inflammatory conditions, and allergic diseases.
• Targeting neutrophil function holds potential for novel therapeutic strategies in children.