Relaxin favors the development of activated human T cells into Th1-like effectors.

Differentiation of naive CD4+ helper T (Th) cells into Th1 or Th2 effectors, as characterized by their opposite pattern of cytokine production, can be influenced by several factors, including hormones. In this study, we demonstrate that porcine relaxin, at concentrations ranging from 10(-10) to 10(-6) M, favors the in vitro development of human antigen-specific T cells into Th1-like effectors and enhances both IFN-gamma mRNA expression and IFN-gamma production by established human T cell clones. The promoting effect of relaxin on the development of IFN-gamma-producing cells was not due to a relaxin-induced release of IL-12 and/or IFN-alpha by antigen-presenting cells.

Defective production of both leukemia inhibitory factor and type 2 T-helper cytokines by decidual T cells in unexplained recurrent abortions.

Leukemia inhibitory factor is essential for embryo implantation, and a shift from type 1 T-helper to type 2 T-helper response at the fetal-maternal interface may contribute to successful pregnancy. We show that LIF production is associated with type 2 T-helper cells, is upregulated by IL-4 and progesterone and is downregulated by IL-12, IFN-gamma and IFN-alpha. We also show a decreased production of LIF, IL-4 and IL-10 by decidual T cells of women with unexplained recurrent abortions in comparison with that of women with normal gestation.

Abnormal production of T helper 2 cytokines interleukin-4 and interleukin-5 by T cells from newborns with atopic parents.

T cell clones were generated from umbelical cord blood lymphocytes (UCBL) of nine newborns with atopic or nonatopic parents and their cytokine secretion profile was assessed. Both phytohemagglutinin-induced and Dermatophagoides pteronyssinus-specific T cell clones from newborns with atopic parents exhibited an enhanced ability to produce the Th2 cytokines interleukin (IL)-4 and IL-5, compared to T cell clones from newborns with nonatopic parents. In contrast, the ability to produce interferon-gamma by UCBL from the two groups of newborns was not different.