Immune responses in neonates

Expert Rev Clin Immunol. 2014 Sep;10(9):1171-84. doi: 10.1586/1744666X.2014.942288. Epub 2014 Aug 4.


Neonates have little immunological memory and a developing immune system, which increases their vulnerability to infectious agents. Recent advances in the understanding of neonatal immunity indicate that both innate and adaptive responses are dependent on precursor frequency of lymphocytes, antigenic dose and mode of exposure. Studies in neonatal mouse models and human umbilical cord blood cells demonstrate the capability of neonatal immune cells to produce immune responses similar to adults in some aspects but not others. This review focuses mainly on the developmental and functional mechanisms of the human neonatal immune system. In particular, the mechanism of innate and adaptive immunity and the role of neutrophils, antigen presenting cells, differences in subclasses of T lymphocytes (Th1, Th2, Tregs) and B cells are discussed. In addition, we have included the recent developments in the neonatal mouse immune system. Understanding neonatal immunity is essential to development of therapeutic vaccines to combat newly emerging infectious agents.

Keywords: B cell; B-reg cell; BCR; CD103 dendritic cell; CD5 cell; CD71 erythroid cell; IL-27 macrophages; NK-cell; RTE; T cell; T follicular cell; TCR; Th 17; Treg cell; adaptive immunity; chemokines; cord blood; dendritic cell; innate immunity; neonates; neutrophils; toll-like receptor; γδ-T cell.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Adaptive Immunity
  • Adult
  • Animals
  • Animals, Newborn / immunology*
  • B-Lymphocyte Subsets / immunology*
  • Humans
  • Immune System / growth & development
  • Immune System / immunology*
  • Immunity, Innate
  • Infant, Newborn / immunology*
  • Mice
  • Models, Animal
  • T-Lymphocyte Subsets / immunology*