A NEW LOOK AT TRANSCRIPTIONAL REGULATION BY AIRE IN mTECs

The deficiency of Aire, a transcriptional regulator whose defect results in the development of autoimmunity, is associated with reduced expression of tissue-restricted self-Ags (TRAs) in medullary thymic epithelial cells (mTECs). Although the mechanisms underlying Aire-dependent expression of TRAs need to be explored, the physical identification of the target(s) of Aire has been hampered by the low and promiscuous expression of TRAs. We have tackled this issue by engineering mice with augmented Aire expression. Integration of the transcriptomic data from Aire-augmented and Aire-deficient mTECs revealed that a large proportion of so-called Aire-dependent genes, including those of TRAs, may not be direct transcriptional targets downstream of Aire. Rather, Aire induces TRA expression indirectly through controlling the heterogeneity of mTECs, as revealed by single-cell analyses. In contrast, Ccl25 emerged as a canonical target of Aire, and we verified this both in vitro and in vivo. Our approach has illuminated the Aire’s primary targets while distinguishing them from the secondary targets

The effects of perilla seed oil ointment for atopic dermatitis

近年アトピー性皮膚炎が増加しており,工ゴマ油を使った食事療法がアレルギー抑制に有用であることが報告されている｡そこで今回,エゴマ油を外用剤として使用するため,亜鉛華単軟膏を基剤とした工コマ軟膏を作製し,アトピー性皮膚炎患者3例を対象にその臨床応用を試みた｡その結果,掻痒感の軽減に効果がみられ,また皮膚症状では,丘疹.表皮剥離,苔癬化,落屑などの所見が改善される傾向が見られた｡The perilla seed oil contains rich α-linolenic acid (α-LNA), parent n-3 fatty acid. The dietary intake of n-3 fatty acid, such as perilla seed oil, has been reported to have some clinical effects in patients with allergic disease. In this report, we prepared the perilla seed oil ointment for atopic dermatitis and the effects of the ointment was evaluated in three patients with atopic dermatitis. This ointment suppressed skin itch, and improved papules, excoriation, lichenification and desquamation of the skin. These results suggest that the perilla seed oil ointment has some effectiveness including suppression of inflammatory changes of the skin in patients with atopic dermatitis

The CCR4–NOT deadenylase complex safeguards thymic positive selection by down-regulating aberrant pro-apoptotic gene expression

A repertoire of T cells with diverse antigen receptors is selected in the thymus. However, detailed mechanisms underlying this thymic positive selection are not clear. Here we show that the CCR4-NOT complex limits expression of specific genes through deadenylation of mRNA poly(A) tails, enabling positive selection. Specifically, the CCR4-NOT complex is up-regulated in thymocytes before initiation of positive selection, where in turn, it inhibits up-regulation of pro-apoptotic Bbc3 and Dab2ip. Elimination of the CCR4-NOT complex permits up-regulation of Bbc3 during a later stage of positive selection, inducing thymocyte apoptosis. In addition, CCR4-NOT elimination up-regulates Dab2ip at an early stage of positive selection. Thus, CCR4-NOT might control thymocyte survival during two-distinct stages of positive selection by suppressing expression levels of pro-apoptotic molecules. Taken together, we propose a link between CCR4-NOT-mediated mRNA decay and T cell selection in the thymus

Down-regulation of GATA1-dependent erythrocyte-related genes in the spleens of mice exposed to a space travel

Secondary lymphoid organs are critical for regulating acquired immune responses. The aim of this study was to characterize the impact of spaceflight on secondary lymphoid organs at the molecular level. We analysed the spleens and lymph nodes from mice flown aboard the International Space Station (ISS) in orbit for 35 days, as part of a Japan Aerospace Exploration Agency mission. During flight, half of the mice were exposed to 1 g by centrifuging in the ISS, to provide information regarding the effect of microgravity and 1 g exposure during spaceflight. Whole-transcript cDNA sequencing (RNA-Seq) analysis of the spleen suggested that erythrocyte-related genes regulated by the transcription factor GATA1 were significantly down-regulated in ISS-flown vs. ground control mice. GATA1 and Tal1 (regulators of erythropoiesis) mRNA expression was consistently reduced by approximately half. These reductions were not completely alleviated by 1 g exposure in the ISS, suggesting that the combined effect of space environments aside from microgravity could down-regulate gene expression in the spleen. Additionally, plasma immunoglobulin concentrations were slightly altered in ISS-flown mice. Overall, our data suggest that spaceflight might disturb the homeostatic gene expression of the spleen through a combination of microgravity and other environmental changes

Identification of mTEC precursor cells

Medullary thymic epithelial cells (mTECs) expressing autoimmune regulator (Aire) are critical for preventing the onset of autoimmunity. However, the differentiation program of Aire-expressing mTECs (Aire+ mTECs) is unclear. Here, we describe novel embryonic precursors of Aire+ mTECs. We found the candidate precursors of Aire+ mTECs (pMECs) by monitoring the expression of receptor activator of nuclear factor-κB (RANK), which is required for Aire+ mTEC differentiation. pMECs unexpectedly expressed cortical TEC molecules in addition to the mTEC markers UEA-1 ligand and RANK and differentiated into mTECs in reaggregation thymic organ culture. Introduction of pMECs in the embryonic thymus permitted long-term maintenance of Aire+ mTECs and efficiently suppressed the onset of autoimmunity induced by Aire+ mTEC deficiency. Mechanistically, pMECs differentiated into Aire+ mTECs by tumor necrosis factor receptor-associated factor 6-dependent RANK signaling. Moreover, nonclassical nuclear factor-κB activation triggered by RANK and lymphotoxin-β receptor signaling promoted pMEC induction from progenitors exhibiting lower RANK expression and higher CD24 expression. Thus, our findings identified two novel stages in the differentiation program of Aire+ mTECs

Antitumor Agents. 282. 2′-( R )- O -Acetylglaucarubinone, a Quassinoid from Odyendyea gabonensis As a Potential Anti-Breast and Anti-Ovarian Cancer Agent

A new quassinoid, designated 2′-(R)-O-acetylglaucarubinone (1), and seven known quassinoids (2–8) were isolated, using bioactivity-guided separation, from the bark of Odyendyea gabonensis (Pierre) Engler [syn. Quassia gabonensis Pierre (Simaroubaceae)]. The structure of 1 was determined by spectroscopic analysis, and by semi-synthesis from glaucarubolone. Complete 1H and 13C NMR assignments of compounds 1–8 were also established from detailed analysis of two-dimensional NMR spectra, and the reported configurations in odyendene (7) and odyendane (8) were corrected. Compound 1 showed potent cytotoxicity against multiple cancer cell lines. Further investigation using various types of breast and ovarian cancer cell lines suggested that 1 does not target the estrogen receptor (ER) or progesterone receptor (PR). When tested against mammary epithelial proliferation in vivo using a Brca1/p53-deficient mice model, 1 also caused significant reduction in mammary duct branching

Mathilde de Mlle de Scudéry : une lecture croisée avec le théâtre de l’époque

Depuis Célinte (1661) jusqu’à La promenade de Versailles (1669), la carrière de nouvelliste de Mlle de Scudéry coïncide avec la montée de Molière sur la scène parisienne, notamment marquée par la création des Précieuses ridicules (1659). En effet, Mathilde (1667) entretient des liens subtils avec Le Misanthrope ou Les amants magnifiques. Le théâtre de Molière n’est pas le seul à présenter des similitudes thématiques et génériques avec la nouvelle. Le discours des personnages de Mathilde semble aussi calqué sur le modèle de la tragédie. Non seulement l’engouement du public pour les spectacles musicaux s’y reflète-t-il, mais on y trouve encore quelques thèmes traités dans le théâtre de l’époque : que l’on songe, par exemple, au motif du « feu » de l’amour ou à celui de la fascination pour la « belle main ».From Célinte (1661) to La promenade de Versailles (1669), the novelistic career of Mlle de Scudéry coincides with Molière’s rise on the Parisian scene, which was marked, notably, by the creation of Les Précieuses ridicules (The Affected Ladies) (1659). Indeed, Mathilde (1667) maintains subtle links with Le Misanthrope or Les amants magnifiques (The Magnificent Lovers). Molière’s drama is not the only one to present thematic and generic similarities to the short story. The discourse of the characters in Mathilde also seems to be derived from the model of tragedy. Not only does it reflect the public’s infatuation with musical entertainment, but it also includes some themes dealt with in the theatre of the time: for example, the motifs regarding the “fire” of love and the fascination with the “lovely hand”

TNF receptor family signaling in the development and functions of medullary thymic epithelial cells

Thymic epithelial cells (TECs) provide the microenvironment required for the development of T cells in the thymus. A unique property of medullary thymic epithelial cells (mTECs) is their expression of a wide range of tissue-restricted self-antigens, critically regulated by the nuclear protein AIRE, which contributes to the selection of the self-tolerant T cell repertoire, thereby suppressing the onset of autoimmune diseases. The TNF receptor family (TNFRF) protein receptor activator of NF-κB (RANK), CD40 and lymphotoxin β receptor (LtβR) regulate the development and functions of mTECs. The engagement of these receptors with their specific ligands results in the activation of the NF-κB family of transcription factors. Two NF-κB activation pathways, the classical and non-classical pathways, promote the development of mature mTECs induced by these receptors. Consistently, TNF receptor-associated factor (TRAF6), the signal transducer of the classical pathway, and NF-κB inducing kinase (NIK), the signal transducer of the non-classical pathway, are essential for the development of mature mTECs. This review summarizes the current understanding of how the signaling by the TNF receptor family controls the development and functions of mTEC