Adiponectin inhibits oxidization-induced differentiation of T helper cells through inhibiting costimulatory CD40 and CD80

Adiponectin is a multifunctional adipokine that has several oligomeric forms in the blood stream, which broadly regulates innate and acquired immunity. Therefore, in this study, we aimed to observe the differentiation of T helper (Th) cells and expression of costimulatory signaling molecules affected by adiponectin. The mRNA and protein expression levels of adiponectin and its receptors in oxidized low density lipoprotein cholesterol-treated endothelial cells were assayed by real time PCR and immunofluorescence. The endothelial cells were then treated with adiponectin with or without adipoR1 or adipoR2 siRNA and co-cultured with T lymphocytes. The distribution of Th1, Th2 and Th17 subsets were assayed by flow cytometry. The effects of adiponectin on costimulatory signaling molecules HLA-DR, CD80, CD86 and CD 40 was also assayed by flow cytometry. The results showed that endothelial cells expressed adiponectin and its receptor adipoR1 and adipoR2, but not T-cadherin. Adiponectin suppressed Th1 and Th17 differentiation through adipoR1 receptor, contributed to the inhibition of CD80 and CD40, and inhibited differentiation of Th1 and Th17 by inhibiting antigen presenting action.

Roles of Embryonic and Adult Lymphoid Tissue Inducer Cells in Primary and Secondary Lymphoid Tissues

The nomenclature "embryonic lymphoid tissue inducer (LTi) cell" reflects the fundamental role of the cell in secondary lymphoid tissue organization. In addition, it is equally important in primary lymphoid tissue development as it regulates central tolerance to self-antigens in the thymus. An adult LTi cell constitutively expresses two sets of tumor necrosis factor (TNF) family members, whereas its embryonic counterpart expresses only one. The first set is lymphotoxin (LT)alpha, LTbeta, and TNFalpha, which are essential for the secondary lymphoid organogenesis during embryogenesis and for maintaining an organized secondary lymphoid structure during adulthood. The second set is OX40- and CD30-ligands, which are critical for memory T cell generation. Adult LTi cells regulate adaptive immune responses by providing LTbetaR signals to stromal cells to maintain secondary lymphoid tissue structure, and determine adaptive immune responses by providing OX40 and CD30 survival signals to activated T cells in memory T cell generation. Along with the consideration of the roles of embryonic LTi cells in primary and secondary lymphoid tissues, this review highlights the roles of adult LTi cells in secondary lymphoid tissue function.

Separation of human suppressor and helper T cells by concanavalin A-coated sheep erythrocytes.

Normal human peripheral blood mononuclear leukocytes (PBML) were activated by concanavalin A (Con A). Con A-activated and non-activated T cells were separated by E (AET) rosettes (2-aminoethylisothiouronium hydrobromide treated sheep erythrocyte rosettes). Purified T cells were rosetted with Con A-coated sheep red blood cells (Con A-SRBC) at 37 degrees C resulting in Con A-SRBC rosetted and non-rosetted T cells. The Con A-SRBC rosetted T lymphocytes in the T lymphocytes from Con A-activated and non-activated PBML were 44.4 +/- 5.4 percent and 16.0 +/- 7.5 percent (Mean +/- S.D.) while the Con A-SRBC non-rosetted T lymphocytes were 55.6 +/- 5.4 percent and 84.0 +/- 7.5 percent respectively. The Con A-SRBC rosetted and non-rosetted T cells were separated by Ficoll-Hypaque gradient centrifugation. Functional studies of Con A-SRBC rosetted and non-rosetted T cells were performed by in vitro tests using pre-amplified reverse hemolytic plaque assay for measuring numbers of immunoglobulin G (IgG) secreting cells and ELISA quantitation of IgG concentration. Both techniques were used to assess the suppressor and helper functions of the Con A-SRBC rosetted and non-rosetted T cells. The Con A-SRBC rosetted cells obtained from T cells of Con A-activated PBML showed strong suppressor activities to normal PBML in both pre-amplified reverse hemolytic plaque assay and sandwidh ELISA of IgG concentration, while the Con A-SRBC non-rosetted T cells demonstrated strong helper activities to normal PBML in both assay systems.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood helper/suppressor lymphocyte ratio in sarcoidosis.

The blood helper/suppressor ratio was measured in 38 patients with biopsy-proved sarcoidosis. There was no relationship between this peripheral helper/suppressor ratio and the activity of the granulomatous process. This test needs further evaluation before its routine use in assessing activity in sarcoidosis.