Regulatory T cells in human geohelminth infection suppress immune responses to BCG and Plasmodium falciparum.

بررسی اثر تماس مستقیم سلولهایT بکر با سلولهای فیبروبلاست تحریک شده با BCG بر القای سلولهایT تنظیمی

Background: Lymph node stromal fibroblasts are interconnected with TCD4+ cells and affect their phenotype and function. Understanding the nature of these interactions under unusual conditions like infections will help to their application in control and regulation of immune responses. Materials and methods: Lymph node fibroblasts were affected in BCG primed immune environment by both in-...

Human cord blood CD4+CD25hi regulatory T cells suppress prenatally acquired T cell responses to Plasmodium falciparum antigens.

In malaria endemic regions, a fetus is often exposed in utero to Plasmodium falciparum blood-stage Ags. In some newborns, this can result in the induction of immune suppression. We have previously shown these modulated immune responses to persist postnatally, with a subsequent increase in a child's susceptibility to infection. To test the hypothesis that this immune suppression is partially med...

Reduced cord blood immune effector-cell responsiveness mediated by CD4+ cells induced in utero as a consequence of placental Plasmodium falciparum infection.

To determine mechanisms of neonatal parasite antigen (Ag)-specific immune suppression associated with placental Plasmodium falciparum infection, we isolated cord blood mononuclear cells (CBMCs) from Gabonese neonates born to mothers with differing histories of P. falciparum infection and performed ex vivo and in vitro studies to evaluate immune regulatory activity. We found increased ex vivo pe...

CD46 engagement on human CD4+ T cells produces T regulatory type 1-like regulation of antimycobacterial T cell responses.

Understanding the regulation of human immune responses is critical for vaccine development and treating infectious diseases. We have previously shown that simultaneous engagement of the T cell receptor (TCR) and complement regulator CD46 on human CD4(+) T cells in the presence of interleukin-2 (IL-2) induces potent secretion of the immunomodulatory cytokine IL-10. These T cells mediate IL-10-de...

Human Cord Blood CD4CD25 Regulatory T Cells Suppress Prenatally Acquired T Cell Responses to Plasmodium falciparum Antigens