Thymus Gland

Stress is one of the basic factors in the etiology of number of diseases. The present study was aimed to investigate the effect of Triphala (Terminalia chebula, Terminalia belerica and Emblica officinalis) on noise-stress induced alterations in the antioxidant status and on the cell-mediated immune response in Wistar strain male albino rats. Noise-stress employed in this study was 100 dB for 4 h/d/15 days and Triphala was used at a dose of 1 g/kg/b.w/48 days.

Immunodeficient mice bearing targeted mutations in the IL2rg gene and engrafted with human immune systems are effective tools for the study of human haematopoiesis, immunity, infectious disease and transplantation biology. The most robust human immune model is generated by implantation of human fetal thymic and liver tissues in irradiated recipients followed by intravenous injection of autologous fetal liver haematopoietic stem cells [often referred to as the BLT (bone marrow, liver, thymus) model].

Cancer is responsible for millions of deaths each year worldwide. Pharmacological intervention with plant-derived products alone or in combination to reverse, suppress, or prevent the cancer progression plays a key role in the fight against this terrible disease. Aerva lanata is an important medicinal plant widely used in traditional systems of medicine like ayurveda and siddha. Ethanolic extract of whole plant of A. lanata exhibited immunomodulatory and antitumor activity.

Lipopolysaccharide (LPS) induces the stress-responsive gene heme oxygenase-1 (HO-1). The present study examined the significance of HO-1 in response to LPS. In HO-1(-/-) mice, as compared with HO-1(+/+) mice, LPS provoked a greater reduction in glomerular filtration rate and renal blood flow, increased renal cytokine expression, and increased activation of nuclear factor (NF)-kappaB. Conversely, HO-1-overexpressing renal epithelial cells, exposed to LPS, exhibited a blunted activation of NF-kappaB and less phosphorylation of its inhibitor, IkappaB.

TGFbeta1 is considered to be required for peripheral maintenance of CD4(+)CD25(+)FOXP3(+) T(reg) cells. However, we demonstrate no reduction in the percentage of such T cells in the spleens and thymi of Tgfb1(-/-) mice. Although putative T(reg) cells, characterized as CD4(+)CD25(+)FOXP3(+)CD62L(+) T cells, are increased in Tgfb1(-/-) mice, they may be inadequate to control activated T cells since the ratio of activated T cells:putative T(reg) cells is several-fold higher in Tgfb1(-/-) mice than in control mice.

CD1d-reactive natural killer T (NKT) cells with an invariant T cell receptor Valpha14 rearrangement are a unique subset of lymphocytes, which play important roles in immune regulation, tumor surveillance, and host defense against pathogens. Vitamin D is a nutrient/hormone that has been shown to regulate conventional T cell responses but not T cell development. The data show that expression of the vitamin D receptor (VDR) is required for normal development and function of iNKT cells. The iNKT cells from VDR KO mice are intrinsically defective and lack T-bet expression.

Exosomes released from different types of cells have been proposed to contribute to intercellular communication. We report that thymic exosome-like particles (ELPs) released from cells of the thymus can induce the development of Foxp3(+) regulatory T (Treg) cells in the lung and liver. Thymic ELPs also induce the conversion of thymic CD4(+)CD25(-) T cells into Tregs. Tregs induced by thymic ELPs suppress the proliferation of CD4(+)CD25(-) T cells in vitro and in vivo.