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

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

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...

Acute Malaria Induces PD1+CTLA4+ Effector T Cells with Cell-Extrinsic Suppressor Function

In acute Plasmodium falciparum (P. falciparum) malaria, the pro- and anti-inflammatory immune pathways must be delicately balanced so that the parasitemia is controlled without inducing immunopathology. An important mechanism to fine-tune T cell responses in the periphery is the induction of coinhibitory receptors such as CTLA4 and PD1. However, their role in acute infections such as P. falcipa...

Induction of T Regulatory Subsets from Naïve CD4+ T Cells after Exposure to Breast Cancer Adipose Derived Stem Cells

Background: Adipose derived stem cells (ASCs) provoke the accumulation and expansion of regulatory T cells, leading to the modulation of immune responses in tumor microenvironment. Objective: To assess the effect of tumoral ASCs on the trend of regulatory T cells differentiation. Methods: Peripheral blood naïve CD4+ T cells were co-cultured with ASCs derived from breast cancer or normal breast ...

IFN-gamma and IL-10 mediate parasite-specific immune responses of cord blood cells induced by pregnancy-associated Plasmodium falciparum malaria.

Available evidence suggests that immune cells from neonates born to mothers with placental Plasmodium falciparum (Pf) infection are sensitized to parasite Ag in utero but have reduced ability to generate protective Th1 responses. In this study, we detected Pf Ag-specific IFN-gamma(+) T cells in cord blood from human neonates whose mothers had received treatment for malaria or who had active pla...