SummaryThe role of naturally occurring regulatory T cells (Treg), known to be phenotypically heterogeneous, in controlling the expression of systemic lupus erythematosus (SLE) is incompletely defined. Therefore, different subpopulations of CD4 + FoxP3 + Tregs in patients with active or inactive SLE were investigated and compared with those of healthy subjects and patients with ankylosing spondylitis (AS). Characterization of different subsets of circulating CD4 + FoxP3 + Tregs was examined using flow cytometry. CD4 + CD25 high T cells were sorted and examined for suppressive activity in vitro. The results showed first that a significant decrease in the frequency of CD4 + CD25 high FoxP3 + T cells was present in patients with active SLE (n = 58), compared with healthy controls (n = 36) and AS patients (n = 23). In contrast, the frequencies of CD25 low FoxP3 + and CD25 ) FoxP3 + CD4 + T cells were significantly increased in patients with active SLE by comparison with the control subjects. The elevation of these two putative Treg subpopulations was associated with lower plasma levels of complement C3 and C4 in patients with SLE. In addition, the ratios of the three subsets of CD4 + FoxP3 + Tregs versus effector T cells (CD4 + CD25 + FoxP3 ) ) were inversely correlated with the titer of antidouble-stranded DNA IgG in patients with inactive, but not active, SLE. These results suggest that the pathogenesis of SLE may be associated with a defect in the homeostatic control of different Treg subsets.

It has been documented that sex hormone may play a role in the pathogenesis of murine lupus. To determine the effect of tamoxifen (TAM) on NZB/W F1 female mice, a total dose of 800 mg (22 mg/kg body weight) of TAM was administered subcutaneously every 2 weeks. The control mice were injected with peanut oil only. After treatment with TAM for 5 months, the mice were killed and immunological parameters were evaluated. The results suggest that NZB/W F1 mice treated with TAM had less severe proteinuria and increased survival rate compared to controls. Flow cytometric analysis of splenocytes revealed a signi®cantly lower percentage of B cells and CD5 B cells in the TAM-treated group. There was a signi®cantly lower serum level of soluble tumour necrosis factor (TNF) receptor I and II molecules in the TAM-treated mice. Immunohistological study showed that control mice had severe immune complex deposition in the kidney. In contrast, TAM-treated mice had much less pathological change. In summary, this study demonstrated that TAM treatment might be able to alleviate the symptoms of lupus nephritis, in¯uence B-cell count, modulate the expression of cytokine receptors and thereby subsequently affect immune function. Further studies to determine the cellular mechanisms in lupus nephritis may increase our understanding of this complex disease and provide additional targets for therapeutic intervention.

Immune dysregulation may be involved in the development of endometriosis. The anti-inflammatory cytokine IL-10 plays an important role in eliminating unwanted cells and cellular debris in a silent way. We investigated the modulatory role of IL-10 in the development of endometriosis. We observed that the serum level of IL-10 in patients with endometriosis was significantly higher than that in healthy subjects or in control subjects with other gynecological disease. Monocyte-derived dendritic cells acquired from male donors and subsequently conditioned with serum from women with endometriosis exhibited a tolerogenic phenotype, including increased IL-10 production, lower IL-12 secretion, and down-regulation of CD86 and HLA-DR molecules. Depletion of IL-10 activity in a C57BL/6 mouse model of surgically induced endometriosis significantly decreased the size of endometrial lesions. In contrast, IL-10 administration promoted the growth of endometrial lesions in this model. In addition, infiltrated plasmacytoid dendritic cells were the primary IL-10-secreting immune cells in endometrial lesions. Our findings suggest that IL-10 may suppress immunity against endometrial implants, contributing to development of endometriosis.

Chronic inflammation drives initiation of hepatocellular carcinoma (HCC), but the underlying mechanisms linking inflammation and tumor formation remain obscure. In this study, we compared the expression of interleukin (IL)-6 and cyclin D1 (CCND1) with the IL-6-induced homeobox gene ISX (intestine-specific homeobox) in 119 paired specimens of HCCs and adjacent normal tissues and also in paired specimens from 11 patients with non-HCCs. In pathologic analysis, ISX exhibited a tumor-specific expression pattern and a high correlation to patient survival time, tumor size, tumor number, and progression stage. Enforced expression of ISX accelerated cell proliferation and tumorigenic activity in hepatoma cells through CCND1 induction. In contrast, short hairpin RNA-mediated attenuation of ISX in hepatoma cells decreased cell proliferation and malignant transformation in vitro and in vivo. A high positive correlation existed in human hepatoma tumors between ISX and CCND1 expression. Together, our results highlight ISX as an important regulator in hepatoma progression with significant potential as a prognostic and therapeutic target in HCCs. Cancer Res; 73(2); 508-18. Ó2012 AACR.

SummarySystemic lupus erythematosus (SLE) is a chronic, systemic autoimmune disease characterized by the loss of tolerance to self-antigen. Because it is currently not known if regulatory T (T reg ) cells are involved in the pathogenesis, we determined the frequency of CD4

Forkhead box P3 (Foxp3) is the major transcription factor controlling the development and function of regulatory T (Treg) cells. Previous studies have indicated epigenetic regulation of Foxp3 expression. Here, we investigated whether the deoxyribonucleic acid (DNA) methyltransferase inhibitor 5-aza-2′-deoxycytidine (5-Aza) applied peripherally could modulate central nervous system (CNS) inflammation, by using a mouse experimental autoimmune encephalomyelitis (EAE) model. We found that disease activity was inhibited in a myelin oligodendrocyte glycoprotein (MOG) peptide-induced EAE mouse briefly pretreated with low-dose (0.15 mg/kg) 5-Aza, ameliorating significant CNS inflammatory responses, as indicated by greatly decreased proinflammatory cytokines. On the contrary, control EAE mice expressed high levels of IFN-γ and interleukin (IL)-17. In addition, 5-Aza treatment in vitro increased GFP expression in CD4 + GFP -T cells isolated from GFP knock-in Foxp3 transgenic mice. Importantly, 5-Aza treatment increased Treg cell numbers, in EAE mice, at both disease onset and peak. However, Treg inhibition assays showed 5-Aza treatment did not enhance per-cell Treg inhibitory function, but did maintain a lower activation threshold for effector cells in EAE mice. In conclusion, 5-Aza treatment prevented EAE development and suppressed CNS inflammation, by increasing the number of Treg cells and inhibiting effector cells in the periphery.

SUMMARYPrevious study suggested that MRL-lpr/lpr mice treated with tamoxifen (TAM) had less severe proteinuria, reduced serum titre of anti-dsDNA autoantibodies and an increased survival rate. To investigate further the regulatory mechanisms of TAM on MRL-lpr/lpr female mice, a total dose of 200 mg per mice (5 . 5 mg/kg) was given every 2 weeks subcutaneously, while the control mice were injected with oil only. After being treated with TAM four times, the mice were killed and cellular functions were evaluated. The TAM-treated groups had smaller sized spleen and

An elevated level of IL‐10 has been considered a critical factor for the development of endometriosis; however, its detailed mechanism and causal relationship remain unclear. This study explored the cellular source and angiogenic activity of local IL‐10 during the early stage of endometriosis. Using a surgical murine model, we found that localised treatment with exogenous recombinant IL‐10 on the day of surgery significantly enhanced endometriotic lesion growth and angiogenesis, whereas blocking local IL‐10 activity using mAbs significantly suppressed those effects. Adoptive transfer of Il10 +/+ plasmacytoid dendritic cells into mice significantly enhanced lesion development, whereas Il10 −/− plasmacytoid dendritic cells significantly inhibited lesion development. Furthermore, in vitro angiogenesis analyses demonstrated that the IL‐10 and IL‐10 receptor pathway stimulated the migratory and tube formation ability of HUVECs as well as ectopic endometrial mesenchymal stem cells through, at least in part, a VEGF‐dependent pathway. We also found that recombinant IL‐10 directly stimulated angiogenesis, based on a Matrigel plug assay as well as a zebrafish model. Pathological results from human endometrioma tissues showed the increased infiltration of CD123+ plasmacytoid dendritic cells and higher percentages of cells that express the IL‐10 receptor and CD31 as compared with the corresponding normal counterparts. Taken together, these results show that IL‐10 secreted from local plasmacytoid dendritic cells promotes endometriosis development through pathological angiogenesis during the early disease stage. This study provides a scientific basis for a potential therapeutic strategy targeting the IL‐10—IL‐10 receptor pathway in the endometriotic milieu. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.