David A. Armstrong

Exposure to maternal mood disorder in utero may program infant neurobehavior via DNA methylation of the glucocorticoid receptor (NR3C1) and 11β-hydroxysteroid dehydrogenase type 2 ( 11β-HSD-2), two placental genes that have been implicated in perturbations of the hypothalamic pituitary adrenocortical (HPA) axis. We tested the relations among prenatal exposure to maternal depression or anxiety, methylation of exon 1F of NR3C1 and 11β-HSD-2, and newborn neurobehavior. Controlling for relevant covariates, infants whose mothers reported depression during pregnancy and showed greater methylation of placental NR3C1 CpG2 had poorer self-regulation, more hypotonia, and more lethargy than infants whose mothers did not report depression. On the other hand, infants whose mothers reported anxiety during pregnancy and showed greater methylation of placental 11β-HSD-2 CpG4 were more hypotonic compared with infants of mothers who did not report anxiety during pregnancy. Our results support the fetal programming hypothesis and suggest that fetal adjustments to cues from the intrauterine environment, in this case an environment that could be characterized by increased exposure to maternal cortisol, may lead to poor neurodevelopmental outcomes.

The role of the non-ELR-containing CXC chemokines IP-10 and Mig in antitumor activity induced by systemic treatment with IL-12 was examined in mice bearing the murine renal adenocarcinoma RENCA. IL-12 treatment produces a potent antitumor effect that is associated with tumor infiltration by CD8+ T lymphocytes. The regression of tumor is associated with the elevated expression of the IFN-gamma-inducible chemokines IP-10 and Mig within the tumor tissue. IP-10 and Mig have been shown to function as chemoattractants for activated T lymphocytes. In animals treated with rabbit polyclonal Abs specific for IP-10 and for Mig, the IL-12-induced regression of RENCA tumors was partially abrogated. This effect was associated with a dramatic inhibition of T cell infiltration. Thus, it appears that IL-12-dependent, T cell-mediated antitumor activity requires the intermediate expression of IP-10 and Mig to recruit antitumor effector T cells to the tumor site.

The contribution of the T cell chemoattractant chemokine IFN-inducible protein 10 (IP-10) in host defense following viral infection of the CNS was examined. IP-10 is expressed by astrocytes during acute encephalomyelitis in mouse hepatitis virus-infected mice, and the majority of T lymphocytes infiltrating into the CNS expressed the IP-10 receptor CXCR3. Treatment of mice with anti-IP-10 antisera led to increased mortality and delayed viral clearance from the CNS as compared with control mice. Further, administration of anti-IP-10 led to a >70% reduction (p </= 0.001) in CD4+ and CD8+ T lymphocyte infiltration into the CNS, which correlated with decreased (p </= 0.01) levels of IFN-gamma. These data indicate that IP-10 functions as a sentinel molecule in host defense and is essential in the development of a protective Th1 response against viral infection of the CNS.