Innate Immunity of Neonates and Infants.
Level 5 - mechanism / opinion, no new human data
Narrative review of immunological mechanisms and conceptual models without original data or systematic methodology.
PubMed 30105028 · doi:10.3389/fimmu.2018.01759
What was done
This narrative review synthesized concepts regarding the developmental transition of the innate immune system from gestation through infancy. It focused on the tolerance mechanisms of neonatal immunity, the functional status of innate lymphoid cells (ILCs) relative to other innate cells (such as monocytes and neutrophils), maternal influences, and structured these mechanisms using a conceptual national defense analogy.
What was found
The abstract provides no empirical numbers or statistical comparisons. It describes qualitative observations: most neonatal innate immune cells, including neutrophils and monocytes, have lower frequencies and more contained activity than those of adults, whereas ILCs show a higher presence and activity level during infancy relative to adulthood.
Why it matters
Understanding the distinct baseline state of neonatal innate immunity—characterized by broad tolerance alongside heightened ILC activity—helps clarify early-life susceptibility to infections and immune-mediated conditions.
Limits
The abstract reports no primary experimental data, clinical cohort observations, or systematic search criteria. All findings are descriptive summaries of existing conceptual and mechanistic literature.
Cited by
- context For the first six months of life, the human immune system is relatively poor at being trained on antigens.