Background: 17β-estradiol (E2) has been known to modulate immune response. Recent studies indicate that E2 at pregnancy level plays a role in regulating T cell response. Objective: To investigate the optimum dose of E2 (from 10-9 to 10-7 M) in mediating the generation of regulatory T cells (Tregs), using naïve human CD4+ T cells from healthy women. Methods: Naïve peripheral T cells were purifie...

Foxp3+ T-regulatory cells (Tregs) normally serve to attenuate immune responses and are key to maintenance of immune homeostasis. Over the past decade, Treg cells have become a major focus of research for many groups, and various functional subsets have been characterized. Recently, the Ikaros family member, Helios, was reported as a marker to discriminate naturally occurring, thymic-derived Tre...

We have previously reported that during mycobacterial infection, naïve CD4(+) T-cell activation is enhanced in the lungs. We investigated the role of chemokine receptor CCR7 and its ligands in the ability of CD11c(+) lung dendritic cells (DCs) to activate naïve CD4(+) T cells during pulmonary infection with Mycobacterium bovis bacillus Calmette-Guérin (BCG). BCG infection resulted in the accumu...

OBJECTIVE To estimate the prognostic value of T-cell subsets in Zambian patients initiating antiretroviral therapy (ART), and to assess the impact of a nutritional intervention on T-cell subsets. METHODS This was a sub-study of a randomised clinical trial of a nutritional intervention for malnourished adults initiating ART. Participants in a randomised controlled trial (NUSTART trial) were en...

Naïve CD4 T cells are triggered to undergo spontaneous proliferation, a proliferative response induced in response to homeostatic stimulation, when exposed to severe lymphopenic environments. They spontaneously acquire proinflammatory effector phenotypes, playing a major role in inducing chronic inflammation in the intestine that is believed to be induced by T cell recognition of commensal anti...

Schistosoma blood flukes, which infect over 200 million people globally, co-opt CD4+ T cell-dependent mechanisms to facilitate parasite development and egg excretion. The latter requires Th2 responses, while the mechanism underpinning the former has remained obscure. Using mice that are either defective in T cell receptor (TCR) signaling or that lack TCRs that can respond to schistosomes, we sh...

Transcriptional pathways controlling the development of CD44(hi) memory phenotype (MP) T cells with "innate-like" functions are not well understood. Here we show that the BTB (bric-a-brac, tramtrack, broad complex) domain-containing protein promyelocytic leukemia zinc finger (PLZF) is expressed in CD44(hi), but not in CD44(lo), CD4(+) T cells. Transgenic expression of PLZF during T cell develop...

Memory phenotype CD4 T cells are found in normal mice and arise through response to environmental antigens or homeostatic mechanisms. The factors that regulate the homeostasis of memory phenotype CD4 cells are not clear. In the present study we demonstrate that there is a marked accumulation of memory phenotype CD4 cells, specifically of the effector memory (T(EM)) phenotype, in lymphoid organs...

BACKGROUND HLA mismatch antigens are major targets of alloreactive T cells in HLA-incompatible stem-cell transplantation, which can trigger severe graft-versus-host disease and reduce survival in transplant recipients. Our objective was to identify T-cell subsets with reduced in vitro reactivity to allogeneic HLA antigens. DESIGN AND METHODS We sorted CD4 and CD8 T-cell subsets from periphera...

BACKGROUND & OBJECTIVES HIV infection is characterized by a perturbation in T cell homeostasis, leading to alteration in T cell subsets. In addition to alteration in differentiation, HIV infection also leads to change in T cell survival and regenerative capacity, as suggested by differential expression of CD127 and CD57. We evaluated the expression patterns of CD127 and CD57 on CD4 and CD8 effe...