title: Development of monocyte Toll-like receptor 2 and Toll-like receptor 4 in preterm newborns during the first few months of life.
abstract: BACKGROUND
  Although the immaturity of Toll-like receptor 2 (TLR2) and Toll-like receptor 4 (TLR4) at birth in preterm newborns is known, their development during the first few months of life remains unclear.
  
  
  METHODS
  Blood monocytes of preterm newborns (gestational age: 24-36 wk) were obtained every 2 wk when possible in order to perform serial measurements of TLR2 and TLR4 surface expression, as well as lipopolysaccharide (LPS)-induced cytokine production. Measurements using monocytes from term newborns and adults were also performed.
  
  
  RESULTS
  The monocytes of preterm newborns obtained at birth displayed reduced surface expression of TLR2 and TLR4, and diminished responses of tumor necrosis factor-α (TNF-α) and interleukin (IL)-8 to LPS stimulation. Regardless of gestational age, monocyte expression of TLR2 and TLR4 in preterm newborns increased rapidly within the first 2 wk after birth, quickly reaching those of term newborns. These increases continued for the following 4-6 wk, although the increase began to plateau. By contrast, LPS-induced production of TNF-α and IL-8 did not elevate over this period in preterm newborns.
  
  
  CONCLUSIONS
  The blood monocytes of preterm newborns display rapid increase in TLR2 and TLR4 expression during the first few months of life, whereas LPS-induced cytokine production functionality did not improve in parallel.
authors: Institutes of Clinical Medicine, College of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors: Chung-Min
authors: CM
authors: Shen
authors: Shih-Chang
authors: SC
authors: Lin
authors: Dau-Ming
authors: DM
authors: Niu
authors: Yu Ru
authors: YR
authors: Kou
mesh_terms: D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D009000:Monocytes / Q000378:metabolism*; D051195:Toll-Like Receptor 2 / Q000378:metabolism*; D051197:Toll-Like Receptor 4 / Q000378:metabolism*
chemical_list: D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4