Fetal and neonatal lymphocytes are relatively resistant to activation and cytokine production when stimulated either via their T-cell antigen receptors or lectins. The molecular mechanism(s) responsible for this phenomenon have not been clearly elucidated. We have hypothesized that such defects in fetal/neonatal T-cell activation may be due to lack of expression of the transcriptional regulatory elements required for T-cell activation. We used reverse transcriptase-polymerase chain reaction to examine both fetal and term neonatal cord bloods for mRNA expression of three transcription factors implicated in T-cell activation: @entity1178 , @entity1639 , and @entity2451 ( @entity2451 subunit). We demonstrate that mRNAs for all three of these regulatory factors are expressed in fetal blood cells by the 27th week of gestation and in term cord bloods. Activation of term @entity1 cord blood mononuclear cells with anti-CD3 monoclonal antibodies resulted in up-regulation of both @entity1178 and @entity1639 mRNAs within 15 min of stimulation. However, secretion of @entity1199 by anti-CD3-stimulated cord blood mononuclear cells was still blunted compared with control cells from adults. We conclude that fetal nucleated blood cells constitutively express important genes for cytokine regulation and are able to increase intracellular accumulation of the mRNAs for these factors in response to anti-CD3 stimulation. Thus, qualitative differences in the capacity to regulate these factors could not be shown in fetal blood cells. Quantitative experiments comparing binding of these transcription factors to the @entity1199 promoter are currently under investigation.

Constitutive expression @entity1639 , XXXX , and @entity2451 mRNA is in nucleated fetal blood cells and up-regulation of @entity1639 and @entity1178 with anti-CD3 stimulation.

@entity1 :: ('9606', 'Species') :: ['infant'] @entity2451 :: ('4790', 'Gene') :: ['p50', 'NF kappa B'] @entity1178 :: ('3725', 'Gene') :: ['c-jun'] @entity1639 :: ('2353', 'Gene') :: ['c-fos'] @entity1199 :: ('3558', 'Gene') :: ['IL-2']
@entity1178 :: (3725,Gene) :: ['c-jun']
