Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Shinichiro Sawa Last modified date:2023.11.22

Professor / Division of Mucosal Immunology / Research Center for Systems Immunology / Medical Institute of Bioregulation


Papers
1. Kazuo Oshima, Akinari Hinoki, Hiroo Uchida, Yujiro Tanaka, Yusuke Okuno, Yasuhiro Go, Chiyoe Shirota, Takahisa Tainaka, Wataru Sumida, Kazuki Yokota, Satoshi Makita, Aitaro Takimoto, Yoko Kano, Shinichiro Sawa, Single-cell RNA sequencing of intestinal immune cells in neonatal necrotizing enterocolitis, Pediatr Surg Int., 10.1007/s00383-023-05461-7, 2023.04.
2. Keiichiro Mine, Xin Tun, Shinya Hatano, Naoto Noguchi, Yoichiro Iwakura, Shinichiro Sawa, Seiho Nagafuchi, Yasunobu Yoshikai, Dermal Vγ6+ γδ T17 Cells Are Involved in Skin Pressure Ulcers in Mice. , The Journal of investigative dermatology , https://doi.org/10.1016/j.jid.2021.12.030, 2022.01.
3. Iori Wada, Shintaro Nakao, Muneo Yamaguchi, Yoshihiro Kaizu, Mitsuru Arima, Shinichiro Sawa, Koh-Hei Sonoda, Retinal VEGF-A Overexpression Is Not Sufficient to Induce Lymphangiogenesis Regardless of VEGF-C Upregulation and Lyve1+ Macrophage Infiltration. , Investigative ophthalmology & visual science, https://doi.org/10.1167/iovs.62.13.17, 62, 13, 17, 2021.10.
4. Takeshi Nitta, Masanori Tsutsumi Sachiko Nitta, Ryunosuke Muro, Emma C. Suzuki, Kenta Nakano, Yoshihiko Tomofuji, Shinichiro Sawa, Tadashi Okamura, Josef M. Penninger, Hiroshi Takayanagi, Fibroblasts as a source of self-antigens for central immune tolerance, Nature Immunology, 10.1038/s41590-020-0756-8, 21, 10, 1172-1180, 2020.08.
5. Kunimura K, Sakata D, Tun X, Uruno T, Ushijima M, Katakai T, Shiraishi A, Aihara R, Kamikaseda Y, Matsubara K, Kanegane H, Sawa S, Eberl G, Ohga S, Yoshikai Y, Fukui Y., S100A4 Protein Is Essential for the Development of Mature Microfold Cells in Peyer's Patches., Cell Rep, 10.1016/j.celrep.2019.10.091, 29, 9, 2823-2834, 2019.12.
6. Kazuki Nagashima, Shinichiro Sawa, Takeshi Nitta, Alejandro Prados, Vasiliki Koliaraki, George Kollias, Tomoki Nakashima, Hiroshi Takayanagi, Targeted deletion of RANKL in M cell inducer cells by the Col6a1-Cre driver, Biochemical and Biophysical Research Communications, 10.1016/j.bbrc.2017.09.004, 493, 1, 437-443, 2017.11, The gut-associated lymphoid tissues (GALTs), including Peyer's patches (PPs), cryptopatches (CPs) and isolated lymphoid follicles (ILFs), establish a host-microbe symbiosis by the promotion of immune reactions against gut microbes. Microfold cell inducer (MCi) cells in GALTs are the recently identified mesenchymal cells that express the cytokine RANKL and initiate bacteria-specific immunoglobulin A (IgA) production via induction of microfold (M) cell differentiation. In the previous study, the Twist2-Cre driver was utilized for gene deletion in mesenchymal cells including MCi cells. In order to investigate MCi cells more extensively, it will be necessary to develop experimental tools in addition to the Twist2-Cre driver mice and characterize such drivers in specificity and efficiency. Here we show that M cell differentiation and IgA production are impaired in the targeted deletion of RANKL by the Col6a1-Cre driver. We compared Col6a1-Cre with Twist2-Cre in terms of the specificity for mesenchymal cells in GALTs. Col6a1-Cre CAG-CAT-EGFP mice exhibited EGFP expression in podoplanin+CD31 cells including MCi cells, while Twist2-Cre mice were shown to target endothelial cells and podoplanin+CD31 cells. Tnfsf11fl/Δ Col6a1-Cre mice exhibited the absence of M cells and severe IgA reduction together with an alteration in gut microbial composition. Moreover, we analyzed germ free mice to test whether changes in the microbiota are the cause of M cell deficiency. M cell differentiation was normal in the CPs/ILFs of germ free mice, indicating that MCi cells induce M cells independently of microbial colonization. This study demonstrates that Col6a1-Cre driver mice are as useful as Twist2-Cre driver mice for functional analyses of GALT-resident mesenchymal cells, including MCi cells..
7. Kazuo Okamoto, Tomoki Nakashima, Masahiro Shinohara, Takako Negishi-Koga, Noriko Komatsu, Asuka Terashima, Shinichiro Sawa, Takeshi Nitta, Hiroshi Takayanagi, Osteoimmunology
The conceptual framework unifying the immune and skeletal systems, Physiological Reviews, 10.1152/physrev.00036.2016, 97, 4, 1295-1349, 2017.10, The immune and skeletal systems share a variety of molecules, including cytokines, chemokines, hormones, receptors, and transcription factors. Bone cells interact with immune cells under physiological and pathological conditions. Osteoimmunology was created as a new interdisciplinary field in large part to highlight the shared molecules and reciprocal interactions between the two systems in both heath and disease. Receptor activator of NF-κB ligand (RANKL) plays an essential role not only in the development of immune organs and bones, but also in autoimmune diseases affecting bone, thus effectively comprising the molecule that links the two systems. Here we review the function, gene regulation, and signal transduction of osteoimmune molecules, including RANKL, in the context of osteoclastogenesis as well as multiple other regulatory functions. Osteoimmunology has become indispensable for understanding the pathogenesis of a number of diseases such as rheumatoid arthritis (RA). We review the various osteoimmune pathologies, including the bone destruction in RA, in which pathogenic helper T cell subsets [such as IL-17-expressing helper T (Th17) cells] induce bone erosion through aberrant RANKL expression.Wealso focus on cellular interactions and the identification of the communication factors in the bone marrow, discussing the contribution of bone cells to the maintenance and regulation of hematopoietic stem and progenitors cells. Thus the time has come for a basic reappraisal of the framework for understanding both the immune and bone systems. The concept of a unified osteoimmune system will be absolutely indispensable for basic and translational approaches to diseases related to bone and/or the immune system..
8. Lucas Onder, Urs Mörbe, Natalia Pikor, Mario Novkovic, Hung Wei Cheng, Thomas Hehlgans, Klaus Pfeffer, Burkhard Becher, Ari Waisman, Thomas Rülicke, Jennifer Gommerman, Christopher G. Mueller, Shinichiro Sawa, Elke Scandella, Burkhard Ludewig, Lymphatic Endothelial Cells Control Initiation of Lymph Node Organogenesis, Immunity, 10.1016/j.immuni.2017.05.008, 47, 1, 80-92.e4, 2017.07, Lymph nodes (LNs) are strategically situated throughout the body at junctures of the blood vascular and lymphatic systems to direct immune responses against antigens draining from peripheral tissues. The current paradigm describes LN development as a programmed process that is governed through the interaction between mesenchymal lymphoid tissue organizer (LTo) cells and hematopoietic lymphoid tissue inducer (LTi) cells. Using cell-type-specific ablation of key molecules involved in lymphoid organogenesis, we found that initiation of LN development is dependent on LTi-cell-mediated activation of lymphatic endothelial cells (LECs) and that engagement of mesenchymal stromal cells is a succeeding event. LEC activation was mediated mainly by signaling through receptor activator of NF-κB (RANK) and the non-canonical NF-κB pathway and was steered by sphingosine-1-phosphate-receptor-dependent retention of LTi cells in the LN anlage. Finally, the finding that pharmacologically enforced interaction between LTi cells and LECs promotes ectopic LN formation underscores the central LTo function of LECs..
9. Kazuki Nagashima, Shinichiro Sawa, Takeshi Nitta, Masanori Tsutsumi, Tadashi Okamura, Josef M. Penninger, Tomoki Nakashima, Hiroshi Takayanagi, Identification of subepithelial mesenchymal cells that induce IgA and diversify gut microbiota, Nature Immunology, 10.1038/ni.3732, 18, 6, 675-682, 2017.05, Immunoglobulin A (IgA) maintains a symbiotic equilibrium with intestinal microbes. IgA induction in the gut-associated lymphoid tissues (GALTs) is dependent on microbial sampling and cellular interaction in the subepithelial dome (SED). However it is unclear how IgA induction is predominantly initiated in the SED. Here we show that previously unrecognized mesenchymal cells in the SED of GALTs regulate bacteria-specific IgA production and diversify the gut microbiota. Mesenchymal cells expressing the cytokine RANKL directly interact with the gut epithelium to control CCL20 expression and microfold (M) cell differentiation. The deletion of mesenchymal RANKL impairs M cell-dependent antigen sampling and B cell-dendritic cell interaction in the SED, which results in a reduction in IgA production and a decrease in microbial diversity. Thus, the subepithelial mesenchymal cells that serve as M cell inducers have a fundamental role in the maintenance of intestinal immune homeostasis..
10. Marie Laure Michel, Christelle Lenoir, Bérangère Massot, Séverine Diem, Benoit Pasquier, Shinichiro Sawa, Rachel Rignault-Bricard, Agnès Lehuen, Gérard Eberl, André Veillette, Maria Leite-de-Moraes, Sylvain Latour, SLAM-associated protein favors the development of iNKT2 over iNKT17 cells, European Journal of Immunology, 10.1002/eji.201646313, 46, 9, 2162-2174, 2016.09, Invariant NKT (iNKT) cells differentiate in the thymus into three distinct lineages defined by their cytokine and transcription factor expression. Signaling lymphocyte activation molecule (SLAM)-associated protein (SAP) is essential for early stages of iNKT cell development, but its role during terminal differentiation of iNKT1, iNKT2, or iNKT17 cells remains unclear. Taking advantage of SAP-deficient mice expressing a Vα14-Jα18 TCRα transgene, we found that SAP is critical not only for IL-4 production but also for the terminal differentiation of IL-4-producing iNKT2 cells. Furthermore, without SAP, the IL-17 producing subset is expanded, while IFN-γ-producing iNKT1 differentiation is only moderately compromised. Lack of SAP reduced the expression of the transcription factors GATA-3 and promyelocytic leukemia zinc finger, but enhanced the levels of retinoic acid receptor-related orphan receptor γt. In the absence of SAP, lineage commitment was actually shifted toward the emergence of iNKT17 over iNKT2 cells. Collectively, our data unveil a new critical regulatory function for SAP in thymic iNKT cell fate decisions..
11. Lynett Danks, Noriko Komatsu, Matteo M. Guerrini, Shinichiro Sawa, Marietta Armaka, George Kollias, Tomoki Nakashima, Hiroshi Takayanagi, RANKL expressed on synovial fibroblasts is primarily responsible for bone erosions during joint inflammation, Annals of the Rheumatic Diseases, 10.1136/annrheumdis-2014-207137, 75, 6, 1187-1195, 2016.06, Objective RANKL is mainly expressed by synovial fibroblasts and T cells within the joints of rheumatoid arthritis patients. The relative importance of RANKL expression by these cell types for the formation of bone erosions is unclear. We therefore aimed to quantify the contribution of RANKL by each cell type to osteoclast differentiation and bone destruction during inflammatory arthritis. Methods RANKL was specifically deleted in T cells (Tnfsf11flox/Δ Lck-Cre), in collagen VI expressing cells including synovial fibroblasts (Tnfsf11flox/Δ Col6a1-Cre) and in collagen II expressing cells including articular chondrocytes (Tnfsf11flox/Δ Col2a1-Cre). Erosive disease was induced using the collagen antibody-induced arthritis (CAIA) and collagen-induced arthritis (CIA) models. Osteoclasts and cartilage degradation were assessed by histology and bone erosions were assessed by micro-CT. Results The inflammatory joint score during CAIA was equivalent in all mice regardless of cell-targeted deletion of RANKL. Significant increases in osteoclast numbers and bone erosions were observed in both the Tnfsf11flox/Δ and the Tnfsf11flox/Δ Lck-Cre groups during CAIA; however, the Tnfsf11flox/Δ Col6a1-Cre mice showed significant protection against osteoclast formation and bone erosions. Similar results on osteoclast formation and bone erosions were obtained in CIA mice. The deletion of RANKL on any cell type did not prevent articular cartilage loss in either model of arthritis used. Conclusions The expression of RANKL on synovial fibroblasts rather than T cells is predominantly responsible for the formation of osteoclasts and erosions during inflammatory arthritis. Synovial fibroblasts would be the best direct target in RANKL inhibition therapies..
12. Takako Negishi-Koga, Hans Jürgen Gober, Eriko Sumiya, Noriko Komatsu, Kazuo Okamoto, Shinichiro Sawa, Ayako Suematsu, Tomomi Suda, Kojiro Sato, Toshiyuki Takai, Hiroshi Takayanagi, Immune complexes regulate bone metabolism through FcRγ signalling, Nature communications, 10.1038/ncomms7637, 6, 2015.03, Autoantibody production and immune complex (IC) formation are frequently observed in autoimmune diseases associated with bone loss. However, it has been poorly understood whether ICs regulate bone metabolism directly. Here we show that the level of osteoclastogenesis is determined by the strength of FcRγ signalling, which is dependent on the relative expression of positive and negative FcγRs (FcγRI/III/IV and IIB, respectively) as well as the availability of their ligands, ICs. Under physiological conditions, unexpectedly, FcγRIII inhibits osteoclastogenesis by depriving other osteoclastogenic Ig-like receptors of FcRγ. Fcgr2b-/-mice lose bone upon the onset of a hypergammaglobulinemia or the administration of IgG1 ICs, which act mainly through FcγRIII. The IgG2 IC activates osteoclastogenesis by binding to FcγRI and FcγRIV, which is induced under inflammatory conditions. These results demonstrate a link between the adaptive immunity and bone, suggesting a regulatory role for ICs in bone resorption in general, and not only in inflammatory diseases..
13. Matteo M. Guerrini, Kazuo Okamoto, Noriko Komatsu, Shinichiro Sawa, Lynett Danks, Josef M. Penninger, Tomoki Nakashima, Hiroshi Takayanagi, Inhibition of the TNF Family Cytokine RANKL Prevents Autoimmune Inflammation in the Central Nervous System, Immunity, 10.1016/j.immuni.2015.10.017, 43, 6, 1174-1185, 2015.01, The central nervous system (CNS) is an immunologically privileged site protected from uncontrolled access of T cells by the blood-brain barrier (BBB), which is breached upon autoimmune inflammation. Here we have shown that receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL) on T cells regulates C-C type chemokine ligand 20 (CCL20) production by astrocytes and T cell localization in the CNS. Importantly, mice specifically lacking RANKL in T cells were resistant to experimental autoimmune encephalomyelitis (EAE) due to altered T cell trafficking. Pharmacological inhibition of RANKL prevented the development of EAE without affecting the peripheral immune response, indicating that RANKL is a potential therapeutic target for treating autoimmune diseases in the CNS..
14. Noriko Komatsu, Kazuo Okamoto, Shinichiro Sawa, Tomoki Nakashima, Masatsugu Ohora, Tatsuhiko Kodama, Sakae Tanaka, Jeffrey A. Bluestone, Hiroshi Takayanagi, Pathogenic conversion of Foxp3 + T cells into TH17 cells in autoimmune arthritis, Nature medicine, 10.1038/nm.3432, 20, 1, 62-68, 2014.01, Autoimmune diseases often result from an imbalance between regulatory T (T reg) cells and interleukin-17 (IL-17)-producing T helper (T H 17) cells; the origin of the latter cells remains largely unknown. Foxp3 is indispensable for the suppressive function of T reg cells, but the stability of Foxp3 has been under debate. Here we show that T H 17 cells originating from Foxp3 + T cells have a key role in the pathogenesis of autoimmune arthritis. Under arthritic conditions, CD25 lo Foxp3 + CD4 + T cells lose Foxp3 expression (herein called exFoxp3 cells) and undergo transdifferentiation into T H 17 cells. Fate mapping analysis showed that IL-17-expressing exFoxp3 T (exFoxp3 T H 17) cells accumulated in inflamed joints. The conversion of Foxp3 + CD4 + T cells to T H 17 cells was mediated by synovial fibroblast-derived IL-6. These exFoxp3 T H 17 cells were more potent osteoclastogenic T cells than were naive CD4 + T cell-derived T H 17 cells. Notably, exFoxp3 T H 17 cells were characterized by the expression of Sox4, chemokine (C-C motif) receptor 6 (CCR6), chemokine (C-C motif) ligand 20 (CCL20), IL-23 receptor (IL-23R) and receptor activator of NF-κB ligand (RANKL, also called TNFSF11). Adoptive transfer of autoreactive, antigen-experienced CD25 lo Foxp3 + CD4 + T cells into mice followed by secondary immunization with collagen accelerated the onset and increased the severity of arthritis and was associated with the loss of Foxp3 expression in the majority of transferred T cells. We observed IL-17 + Foxp3 + T cells in the synovium of subjects with active rheumatoid arthritis (RA), which suggests that plastic Foxp3 + T cells contribute to the pathogenesis of RA. These findings establish the pathological importance of Foxp3 instability in the generation of pathogenic T H 17 cells in autoimmunity..
15. Shinichiro Sawa, Roles of RORγt+ innate lymphoid cells in mucosal tissues of mouse and human, Japanese Journal of Clinical Immunology, 10.2177/jsci.36.11, 36, 1, 11-16, 2013.01, Innate Lymphoid cells (ILCs) are recently defined lymphocytes composed of several subsets such as Natural Killer (NK), Natural Helper (NH) and RORγt+ cells, which have no antigen receptors but exhibit rapid cytokine production after stimulation. Murine RORγt+ ILCs can be classified either as CCR6+c-kithighIL-7Rahigh or CCR6-NKp46+ cells. The former ones play roles on the formation of secondary lymphoid tissues and the later ones contribute to the maintenance of intestinal epithelial integrity by producing IL-22. Human fetal intestine, tonsil and lympho nodes harbor both NKp44 positive and negative RORγt+ ILC subsets. Since human Crohn's disease patients have increased number of RORγt+ ILCs in the in‰amed intestine, roles of RORγt+ ILCs on the pathogenesis of Crohn's disease became of great interest..
16. Marie Cherrier, Shinichiro Sawa, Gérard Eberl, Notch, Id2, and RORγt sequentially orchestrate the fetal development of lymphoid tissue inducer cells, Journal of Experimental Medicine, 10.1084/jem.20111594, 209, 4, 729-740, 2012.04, AbstracyLymphoid tissue development is initiated during embryogenesis by the migration of lymphoid tissue inducer (LTi) cells from the fetal liver to the periphery, where they induce the formation of lymph nodes and Peyer's patches. In the fetal liver, a subset of common lymphoid progenitors (CLPs) that expresses the integrin α4β7 gives rise to LTi cells, a process strictly dependent on the expression of the transcriptional repressor Id2 and the nuclear hormone receptor retinoic acid-related orphan receptor γ t (RORγt). In this study, we show that Id2 and RORγt are sequentially up-regulated during LTi cell development, matching two waves of differentiation with opposite requirements for Notch signaling. Both the expression of Id2 and Notch are required for the generation of α4β7 + RORγt - fetal progenitors, but Notch subsequently blocks progression to the RORγt + stage and final maturation of LTi cells. Notch is therefore a necessary switch to engage the LTi developmental pathway, but needs to be turned off later to avoid diversion to the T cell fate..
17. Caspar Ohnmacht, Rute Marques, Laura Presley, Shinichiro Sawa, Matthias Lochner, Gérard Eberl, Intestinal microbiota, evolution of the immune system and the bad reputation of pro-inflammatory immunity, Cellular Microbiology, 10.1111/j.1462-5822.2011.01577.x, 13, 5, 653-659, 2011.05, The mammalian intestine provides a unique niche for a large community of bacterial symbionts that complements the host in digestive and anabolic pathways, as well as in protection from pathogens. Only a few bacterial phyla have adapted to this predominantly anaerobic environment, but hundreds of different species create an ecosystem that affects many facets of the host's physiology. Recent data show how particular symbionts are involved in the maturation of the immune system, in the intestine and beyond, and how dysbiosis, or alteration of that community, can deregulate immunity and lead to immunopathology. The extensive and dynamic interactions between the symbionts and the immune system are key to homeostasis and health, and require all the blends of so-called regulatory and pro-inflammatory immune reactions. Unfortunately, pro-inflammatory immunity leading to the generation of Th17 cells has been mainly associated with its role in immunopathology. Here we discuss the view that the immune system in general, and type 17 immunity in particular, develop to maintain the equilibrium of the host with its symbionts..
18. Shinichiro Sawa, Matthias Lochner, Naoko Satoh-Takayama, Sophie Dulauroy, Marion Bérard, Melanie Kleinschek, Daniel Cua, James P. Di Santo, Gérard Eberl, RORγt+ innate lymphoid cells regulate intestinal homeostasis by integrating negative signals from the symbiotic microbiota, Nature Immunology, 10.1038/ni.2002, 12, 4, 320-328, 2011.04, Lymphoid cells that express the nuclear hormone receptor RORβ 3t are involved in containment of the large intestinal microbiota and defense against pathogens through the production of interleukin 17 (IL-17) and IL-22. They include adaptive IL-17-producing helper T cells (TH 17 cells), as well as innate lymphoid cells (ILCs) such as lymphoid tissueĝ€" inducer (LTi) cells and IL-22-producing NKp46+ cells. Here we show that in contrast to TH 17 cells, both types of RORγ t + ILCs constitutively produced most of the intestinal IL-22 and that the symbiotic microbiota repressed this function through epithelial expression of IL-25. This function was greater in the absence of adaptive immunity and was fully restored and required after epithelial damage, which demonstrates a central role for RORγ t+ ILCs in intestinal homeostasis. Our data identify a finely tuned equilibrium among intestinal symbionts, adaptive immunity and RORγ t+ ILCs..
19. Naoko Satoh-Takayama, Sarah Lesjean-Pottier, Shinichiro Sawa, Christian A.J. Vosshenrich, Gérard Eberl, James P. Di Santo, Lymphotoxin-β receptor-independent development of intestinal IL-22-producing NKp46+ innate lymphoid cells, European Journal of Immunology, 10.1002/eji.201040851, 41, 3, 780-786, 2011.03, The natural cytotoxicity receptor NKp46 is an activating receptor expressed by several distinct innate lymphoid cell (ILC) subsets, including NK cells, some γδ T cells and intestinal RORγt+IL-22+ cells (NCR22 cells, IL-22-producing NKp46+ cell). NCR22 cells may play a role in mucosal barrier function through IL-22-mediated production of anti-bacterial peptides from intestinal epithelial cells. Previous studies identified a predominant proportion of NCR22 cells in gut cryptopatches (CP), lymphoid structures that are strategically positioned to collect and integrate signals from luminal microbes; however, whether CP or other lymphoid structures condition NCR22 cell differentiation is not known. Programmed and inducible lymphoid tissue development requires cell-surface-expressed lymphotoxin (LT)α1β2 heterotrimers (provided by lymphoid tissue inducer (LTi) cells) to signal lymphotoxin-β receptor (LTR)+ stromal cells. Here, we analyzed NCR22 cells in LTβR-deficient Ncr1GFP/+ mice that lack organized secondary lymphoid tissues. We found that NCR22 cells develop in the absence of LTβR, become functionally competent and localize to the lamina propria under steady-state conditions. Following infection of LTβR-/- mice with the Gram-negative pathogen Citrobacter rodentium, IL-22 production from NCR22 cells was not affected. These results indicate that organized lymphoid tissue structures are not critical for the generation of an intact and fully functional intestinal NCR22 cell compartment..
20. Matthias Lochner, Marion Bérard, Shinichiro Sawa, Siona Hauer, Valérie Gaboriau-Routhiau, Tahia Diana Fernandez, Johannes Snel, Philippe Bousso, Nadine Cerf-Bensussan, Gérard Eberl, Restricted microbiota and absence of cognate TCR antigen leads to an unbalanced generation of Th17 cells, Journal of Immunology, 10.4049/jimmunol.1001723, 186, 3, 1531-1537, 2011.02, Retinoic acid-related orphan receptor (ROR)γt+ TCRαβ+ cells expressing IL-17, termed Th17 cells, are most abundant in the intestinal lamina propria. Symbiotic microbiota are required for the generation of Th17 cells, but the requirement for microbiota-derived Ag is not documented. In this study, we show that normal numbers of Th17 cells develop in the intestine of mice that express a single TCR in the absence of cognate Ag, whereas the microbiota remains essential for their development. However, such mice, or mice monocolonized with the Th17-inducing segmented filamentous bacteria, fail to induce normal numbers of Foxp3+ RORγt+ T cells, the regulatory counterpart of IL-17 +RORγt+ T cells. These results demonstrate that a complex microbiota and cognate Ag are required to generate a properly regulated set of RORγt+ T cells and Th17 cells..
21. Matthias Lochner, Caspar Ohnmacht, Laura Presley, Pierre Bruhns, Mustapha Si-Tahar, Shinichiro Sawa, Gérard Eberl, Microbiota-induced tertiary lymphoid tissues aggravate inflammatory disease in the absence of RORγt and LTi cells, Journal of Experimental Medicine, 10.1084/jem.20100052, 208, 1, 125-134, 2011.01, The programmed development of lymph nodes and Peyer's patches during ontogeny requires lymphoid tissue inducer (LTi) cells that express the nuclear hormone receptor RORγt. After birth, LTi cells in the intestine cluster into cryptopatches, the precursors of isolated lymphoid follicles (ILFs), which are induced to form by symbiotic bacteria and maintain intestinal homeostasis. We show that in RORγt-deficient mice, which lack LTi cells, programmed lymphoid tissues, ILFs, and Th17 cells, bacterial containment requires the generation of large numbers of tertiary lymphoid tissues (tLTs) through the activity of B cells. However, upon epithelial damage, these mice develop severe intestinal inflammation characterized by extensive recruitment of neutrophils and IgG+ B cells, high expression of activation-induced deaminase in tLTs, and wasting disease. The pathology was prevented by antibiotic treatment or inhibition of lymphoid tissue formation and was significantly decreased by treatment with intravenous immunoglobulin G (IVIG). Our data show that intestinal immunodeficiency, such as an absence in RORγt-mediated proinflammatory immunity, can be compensated by increased lymphoid tissue genesis. However, this comes at a high cost for the host and can lead to a deregulated B cell response and aggravated inflammatory pathology..
22. Shinichiro Sawa, Marie Cherrier, Matthias Lochner, Naoko Satoh-Takayama, Hans Jörg Fehling, Francina Langa, James P. Di Santo, Gérard Eberl, Lineage relationship analysis of RORγt+ innate lymphoid cells, Science, 10.1126/science.1194597, 330, 6004, 665-669, 2010.10, Lymphoid tissue - inducer (LTi) cells initiate the development of lymphoid tissues through the activation of local stromal cells in a process similar to inflammation. LTi cells express the nuclear hormone receptor RORγt, which also directs the expression of the proinflammatory cytokine interleukin-17 in T cells. We show here that LTi cells are part of a larger family of proinflammatory RORγt+ innate lymphoid cells (ILCs) that differentiate from distinct fetal liver RORγt+ precursors. The fate of RORγt+ ILCs is determined by mouse age, and after birth, favors the generation of cells involved in intestinal homeostasis and defense. Contrary to RORγt+ T cells, however, RORγt + ILCs develop in the absence of microbiota. Our study indicates that RORγt+ ILCs evolve to preempt intestinal colonization by microbial symbionts..
23. Naoko Satoh-Takayama, Sarah Lesjean-Pottier, Paulo Vieira, Shinichiro Sawa, Gerard Eberl, Christian A.J. Vosshenrich, James P. Di Santo, IL-7 and IL-15 independently program the differentiation of intestinal CD3-NKp46+ cell subsets from Id2-dependent precursors, Journal of Experimental Medicine, 10.1084/jem.20092029, 207, 2, 273-280, 2010.02, The natural cytotoxicity receptor NKp46 (encoded by Ncr1) was recently shown to identify a subset of noncytotoxic, Rag-independent gut lymphocytes that express the transcription factor Rorc, produce interleukin (IL)-22, and provide innate immune protection at the intestinal mucosa. Intestinal CD3 -NKp46+ cells are phenotypically heterogeneous, comprising a minority subset that resembles classical mature splenic natural killer (NK) cells (NK1.1+, Ly49+) but also a large CD127 +NK1.1- subset of lymphoid tissue inducer (LTi)-like Rorc+ cells that has been proposed to include NK cell precursors. We investigated the developmental relationships between these intestinal CD3 -NKp46+ subsets. Gut CD3-NKp46+ cells were related to LTi and NK cells in requiring the transcriptional inhibitor Id2 for normal development. Overexpression of IL-15 in intestinal epithelial cells expanded NK1.1+ cells within the gut but had no effect on absolute numbers of the CD127+NK1.1-Rorc+ subset of CD3-NKp46+ cells. In contrast, IL-7 deficiency strongly reduced the overall numbers of CD3-NKp46+NK1. 1- cells that express Rorc and produce IL-22 but failed to restrict homeostasis of classical intestinal NK1.1+ cells. Finally, in vivo fate-mapping experiments demonstrated that intestinal NK1.1 +CD127- cells are not the progeny of Rorc-expressing progenitors, indicating that CD127+NK1.1-Rorc+ cells are not canonical NK cell precursors. These studies highlight the independent cytokine regulation of functionally diverse intestinal NKp46 + cell subsets..
24. Gérard Eberl, Shinichiro Sawa, Opening the crypt
current facts and hypotheses on the function of cryptopatches, Trends in Immunology, 10.1016/j.it.2009.11.004, 31, 2, 50-55, 2010.02, Cryptopatches, small aggregates of lymphoid cells found in the intestinal lamina propria, have been assigned many functions specific to gut immunity. Populated with seemingly immature lymphoid cells and dendritic cells, it has been suggested that cryptopatches maturate intraepithelial lymphocytes, Th17 cells, IL-22-producing NKp46+ cells, and lymphoid tissues in response to the gut microbiota. Some of these issues, however, remain hotly debated. Therefore, cryptopatches are coming to the forefront of gut immunology and warrant a comprehensive discussion of their role in the development of the immune system..
25. Naoko Satoh-Takayama, Christian A.J. Vosshenrich, Sarah Lesjean-Pottier, Shinichiro Sawa, Matthias Lochner, Frederique Rattis, Jean Jacques Mention, Kader Thiam, Nadine Cerf-Bensussan, Ofer Mandelboim, Gerard Eberl, James P. Di Santo, Microbial Flora Drives Interleukin 22 Production in Intestinal NKp46+ Cells that Provide Innate Mucosal Immune Defense, Immunity, 10.1016/j.immuni.2008.11.001, 29, 6, 958-970, 2008.12, Natural killer (NK) cells are innate lymphocytes with spontaneous antitumor activity, and they produce interferon-γ (IFN-γ) that primes immune responses. Whereas T helper cell subsets differentiate from naive T cells via specific transcription factors, evidence for NK cell diversification is limited. In this report, we characterized intestinal lymphocytes expressing the NK cell natural cytotoxicity receptor NKp46. Gut NKp46+ cells were distinguished from classical NK cells by limited IFN-γ production and absence of perforin, whereas several subsets expressed the nuclear hormone receptor retinoic acid receptor-related orphan receptor t (RORγt) and interleukin-22 (IL-22). Intestinal NKp46+IL-22+ cells were generated via a local process that was conditioned by commensal bacteria and required RORγt. Mice lacking IL-22-producing NKp46+ cells showed heightened susceptibility to the pathogen Citrobacter rodentium, consistent with a role for intestinal NKp46+ cells in immune protection. RORγt-driven diversification of intestinal NKp46+ cells thereby specifies an innate cellular defense mechanism that operates at mucosal surfaces..
26. Matthias Lochner, Lucie Peduto, Marie Cherrier, Shinichiro Sawa, Francina Langa, Rosa Varona, Dieter Riethmacher, Mustapha Si-Tahar, James P. Di Santo, Gérard Eberl, In vivo equilibrium of proinflammatory IL-17+ and regulatory IL-10+ Foxp3+ RORγt+ T cells, Journal of Experimental Medicine, 10.1084/jem.20080034, 205, 6, 1381-1393, 2008.06, The nuclear hormone receptor retinoic acid receptor-related orphan receptor γt (RORγt) is required for the generation of T helper 17 cells expressing the proinflammatory cytokine interleukin (IL)-17. In vivo, however, less than half of RORγt+ T cells express IL-17. We report here that RORγt+ Tαβ cells include Foxp3+ cells that coexist with IL-17-producing RORγt+ Tαβ cells in all tissues examined. The Foxp3+ RORγt+ Tαβ express IL-10 and CCL20, and function as regulatory T cells. Furthermore, the ratio of Foxp3+ to IL-17-producing RORγt + Tαβ cells remains remarkably constant in mice enduring infection and inflammation. This equilibrium is tuned in favor of IL-10 production by Foxp3 and CCL20, and in favor of IL-17 production by IL-6 and IL-23. In the lung and skin, the largest population of RORγt+ T cells express the γδ T cell receptor and produce the highest levels of IL-17 independently of IL-6. Thus, potentially antagonistic proinflammatory IL-17-producing and regulatory Foxp3+ RORγt+ T cells coexist and are tightly controlled, suggesting that a perturbed equilibrium in RORγt+ T cells might lead to decreased immunoreactivity or, in contrast, to pathological inflammation..
27. Khie Khiong, Masaaki Murakami, Chika Kitabayashi, Naoko Ueda, Shinichiro Sawa, Akemi Sakamoto, Brian L. Kotzin, Stephen J. Rozzo, Katsuhiko Ishihara, Marileila Verella-Garcia, John Kappler, Philippa Marrack, Toshio Hirano, Homeostatically proliferating CD4+ T cells are involved in the pathogenesis of an Omenn syndrome murine model, Journal of Clinical Investigation, 10.1172/JCI30513, 117, 5, 1270-1281, 2007.05, Patients with Omenn syndrome (OS) have hypomorphic RAG mutations and develop varying manifestations of severe combined immunodeficiency. It is not known which symptoms are caused directly by the RAG mutations and which depend on other polymorphic genes. Our current understanding of OS is limited by the lack of an animal model. In the present study, we identified a C57BL/10 mouse with a spontaneous mutation in, and reduced activity of, RAG1. Mice bred from this animal contained high numbers of memory-phenotype T cells and experienced hepatosplenomegaly and eosinophilia, had oligoclonal T cells, and demonstrated elevated levels of IgE, major symptoms of OS. Depletion of CD4+ T cells in the mice caused a reduction in their IgE levels. Hence these "memory mutant" mice are a model for human OS; many symptoms of their disease were direct results of the Rag hypomorphism and some were caused by malfunctions of their CD4+ T cells..
28. Naoko Ueda, Hiroko Kuki, Daisuke Kamimura, Shinichiro Sawa, Kenichiro Seino, Takuya Tashiro, Ken Ichi Fushuku, Masaru Taniguchi, Toshio Hirano, Masaaki Murakami, CD1d-restricted NKT cell activation enhanced homeostatic proliferation of CD8+ T cells in a manner dependent on IL-4, International Immunology, 10.1093/intimm/dxl073, 18, 9, 1397-1404, 2006.09, CD1d-restricted NKT cells are activated by TCR-mediated stimulation via CD1d plus lipid antigens such as alpha-galactosylceramide (α-GalCer). These cells suppressed autoimmunity and graft rejection, but sometimes enhanced resistance to infection and tumor immunity. This double-action phenomenon of NKT cells is partly explained by cytokines produced by NKT cells. Therefore, roles of cytokines from activated NKT cells have been extensively examined; however, their roles on T cell homeostatic proliferation in lymphopenic condition have not been investigated. Here, we showed that α-GalCer enhanced homeostatic proliferation of CD8+ but not CD4+ T cells and this effect of α-GalCer was required for NKT cells. IL-4 was essential and sufficient for this NKT cell action on CD8+ T cell homeostatic proliferation. Importantly, the expression of IL-4Rα and STAT6 in CD8+ T cells was essential for the NKT activity, indicating a direct action of IL-4 on CD8+ T cells. Consistent with this, the level of IL-4Rα expression on memory phenotype CD8+ T cells was higher than that on naive phenotype one and CD4+ T cells. Thus, these results showed the 'involvement' of IL-4 that is produced from activated NKT cells for CD8+ T cell homeostatic proliferation in vivo..
29. Shinichiro Sawa, Daisuke Kamimura, Gui Hua Jin, Hideyuki Morikawa, Hokuto Kamon, Mika Nishihara, Katsuhiko Ishihara, Masaaki Murakami, Toshio Hirano, Autoimmune arthritis associated with mutated interleukin (IL)-6 receptor gp130 is driven by STAT3/IL-7-dependent homeostatic proliferation of CD4 + T cells, Journal of Experimental Medicine, 10.1084/jem.20052187, 203, 6, 1459-1470, 2006.06, Mice homozygous for the F759 mutation in the gp130 interleukin (IL)-6 receptor subunit have enhanced gp130-mediated signal transducer and activator of transcription (STAT)3 activation and spontaneously developed a lymphocyte-mediated rheumatoid arthritis-like joint disease. Here, we show that the development of the disease is dependent on both major histocompatibility complex (MHC) II-restricted CD4+ T cells and IL-6 family cytokines. In spite of the necessity for CD4+ T cells, the gp130 mutation was only required in nonhemtopoietic cells for the disease. The gp130 mutation resulted in enhanced production of IL-7. Conditional knockout of STAT3 in nonlymphoid cells showed that the enhancement of IL-7 production was dependent on STAT3 activation by IL-6 family cytokines. Homeostatic proliferation of CD4+ T cells was enhanced in gp130 mutant mice and acceleration of homeostatic proliferation enhanced the disease, whereas the inhibition of homeostatic proliferation suppressed the disease. Anti-IL-7 antibody treatment inhibited not only the enhanced homeostatic proliferation, but also the disease in gp130 mutant mice. Thus, our results show that autoimmune disease in gp130 mutant mice is caused by increased homeostatic proliferation of CD4+ T cells, which is due to elevated production of IL-7 by nonhematopoietic cells as a result of IL-6 family cytokine-gp130-STAT3 signaling. JEM.
30. Hidemitsu Kitamura, Hokuto Kamon, Shinichiro Sawa, Sung Joo Park, Nobuhiko Katunuma, Katsuhiko Ishihara, Masaaki Murakami, Toshio Hirano, IL-6-STAT3 controls intracellular MHC class II αβ dimer level through cathepsin S activity in Dendritic Cells, Immunity, 10.1016/j.immuni.2005.09.010, 23, 5, 491-502, 2005.11, We found IL-6-STAT3 pathway suppresses MHC class II (MHCII) expression on dendritic cells (DCs) and attenuates T cell activation. Here, we showed that IL-6-STAT3 signaling reduced intracellular MHCII αβ dimmer, Ii, and H2-DM levels in DCs. IL-6-mediated STAT3 activation decreased cystatin C level, an endogenous inhibitor of cathepsins, and enhanced cathepsin activities. Importantly, cathepsin S inhibitors blocked reduction of MHCII αβ dimer, Ii, and H2-DM in the IL-6-treated DCs. Overexpression of cystatin C suppressed IL-6-STAT3-mediated increase of cathepsin S activity and reduction of MHCII αβ dimer, Ii, and H2-DM levels in DCs. Cathepsin S overexpression in DCs decreased intracellular MHCII αβ dimer, Ii, and H2-DM levels, LPS-mediated surface expression of MHCII and suppressed CD4 + T cell activation. IL-6-gp130-STAT3 signaling in vivo decreased cystatin C expression and MHCII αβ dimer level in DCs. Thus, IL-6-STAT3-mediated increase of cathepsin S activity reduces the MHCII αβ dimer, Ii, and H2-DM levels in DCs, and suppresses CD4+ T cell-mediated immune responses..
31. Masaaki Murakami, Shinichiro Sawa, Daisuke Kamimura, Hokuto Kamon, Hidemitsu Kitamura, Takaya Kawabe, Park Sung-Joo, Katsuhiko Ishihara, Toshio Hirano, Hyperactivation of gp130-mediated STAT3 signaling induces a rheumatoid arthritis-like disease that is dependent on MHC class II restricted CD4+ T cells, International Congress Series, 10.1016/j.ics.2005.07.096, 1285, 207-211, 2005.11, Mice having a point mutation of IL-6 signal transducer, gp130, named gp130F759 induced a rheumatoid arthritis-like disease. The disease induction is totally dependent on mature lymphocytes, since no arthritis-like disease induced in a double mutant between gp130F759 and RAG2KO mice. We prepared several other double mutants including gp130F759/IgMKO, gp130F759/CD8KO, gp130F759/CIITAKO and gp130F759/CD4KO and analyzed the development of the arthritis. We found that development of the disease attenuated in gp130F759/CIITAKO and gp130F759/CD4KO, suggesting the MHC class II-restricted CD4+ T cells are important for the disease development. We showed memory/activated phenotype of CD4+ T cells increased in gp130F759 mice. Since activation of CD4+ T cells is mainly controlled by dendritic cells (DC) in vivo, we investigated this feature of DC in gp130F759 mice. We isolated DCs from superficial lymph nodes and observed that IL-6-mediated signaling suppresses maturation of DCs in vivo. However, total number of DCs in vivo significantly increased in gp130F759 mice compared with wild type controls. Thus, we hypothesize that the rheumatoid arthritis-like disease in gp130F759 mice is induced by an interaction between CD4+ T cells and DC under gp130F759 signal regulation..
32. Daisuke Kamimura, Naoko Ueda, Yukihisa Sawa, Shinji Hachida, Toru Atsumi, Takayuki Nakagawa, Shinichiro Sawa, Gui Hua Jin, Haruhiko Suzuki, Katsuhiko Ishihara, Masaaki Murakami, Toshio Hirano, Evidence of a novel IL-2/15Rβ-targeted cytokine involved in homeostatic proliferation of memory CD8+ T cells, Journal of Immunology, 173, 10, 6041-6049, 2004.11, The homeostasis of memory CD8+ T cells is regulated by cytokines. IL-15 is shown to promote the proliferation of Memory CD8+ T cells, while IL-2 suppresses their division in vivo. This inhibitory efect of IL-2 appears to occur indirectly, through other cell populations including CD25+CD4+ T cells; however, the details of this mechanism remain unclear. In this study, we show that 1) both Ag-experienced and memory phenotype CD8+ T cells divided after the depletion of IL-2 in vivo; 2) this division occurred normally and CD44highIL-2/ 15Rβhigh CD8+ T cells generated after IL-2 depletion in IL-15 knockout (KO) and in IL-7-depleted IL-15 KO mice; 3) surprisingly, the blockade of IL-2/15Rβ signaling in IL-2-depleted IL-15 KO mice completely abolished the division of memory CD8+ T cells, although the only cytokines known to act through IL-2/15Rβ are IL-2 and IL-15; and 4) the expression of IL-2/15Rβ molecules on memory CD8+ T cells was required for their division induced by IL-2 depletion. These results demonstrate that the depletion of IL-2 in vivo induced memory CD8+ T cell division by an IL-15-independent but by an IL-2/15Rβ-dependent mechanism, suggesting the existence of a novel IL-2/15Rβ-utilizing cytokine that acts directly on memory CD8+ T cells to promote cell division..
33. Sung Joo Park, Takayuki Nakagawa, Hidemitsu Kitamura, Toru Atsumi, Hokuto Kamon, Shinichiro Sawa, Daisuke Kamimura, Naoko Ueda, Yoichiro Iwakura, Katsuhiko Ishihara, Masaaki Murakami, Toshio Hirano, IL-6 regulates in vivo dendritic cell differentiation through STAT3 activation, Journal of Immunology, 10.4049/jimmunol.173.6.3844, 173, 6, 3844-3854, 2004.09, Dendritic cells (DCs) orchestrate immune responses according to their state of maturation. In response to infection, DCs differentiate into mature cells that initiate immune responses, while in the absence of infection, most of them remain in an immature form that induces tolerance to self Ags. Understanding what controls these opposing effects is an important goal for vaccine development and prevention of unwanted immune responses. A crucial question is what cytokine(s) regulates DC maturation in the absence of infection. In this study, we show that IL-6 plays a major role in maintaining immature DCs. IL-6 knockout (KO) mice had increased numbers of mature DCs, indicating that IL-6 blocks DC maturation in vivo. We examined this effect further in knockin mice expressing mutant versions of the IL-6 signal transducer gp130, with defective signaling through either Src homology region 2 domain-containing phosphatase 2/GabMAPK (gp130F759/F759) or STAT3 (gp130FxxQ/FxxQ), and combined gp130 and IL-6 defects (gp130F759/F759/IL-6 KO mice). Importantly, we found STAT3 activation by IL-6 was required for the suppression of LPS-induced DC maturation. In addition, STAT3 phosphorylation in DCs was regulated by IL-6 in vivo, and STAT3 was necessary for the IL-6 suppression of bone marrow-derived DC activation/maturation. DC-mediated T cell activation was enhanced in IL-6 KO mice and suppressed in gp130F759/F759 mice. IL-6 is thus a potent regulator of DC differentiation in vivo, and IL-6-gp130-STAT3 signaling in DCs may represent a critical target for controlling T cell-mediated immune responses in vivo..
34. Katsuhiko Ishihara, Shinichiro Sawa, Hideto Ikushima, Seiichi Hirota, Toru Atsumi, Daisuke Kamimura, Sung Joo Park, Masaaki Murakami, Yukihiko Kitamura, Yoichiro Iwakura, Toshio Hirano, The point mutation of tyrosine 759 of the IL-6 family cytokine receptor gp130 synergizes with HTLV-1 pX in promoting rheumatoid arthritis-like arthritis, International Immunology, 10.1093/intimm/dxh045, 16, 3, 455-465, 2004.03, Rheumatoid arthritis (RA) is a polygenic autoimmune disease. The autoimmunity develops from synergistic actions of genetic and environmental factors. We generated a double-mutant mouse by crossing two murine models of RA, a gp130 mutant knock-in mouse (gp130F759/F759) and an HTLV-1 pX transgenic mouse (pX-Tg), in a C57BL/6 background, which is resistant to arthritis. The mice spontaneously developed severe arthritis with a much earlier onset than the gp130F759/F759 mice and with a much higher incidence than did the pX-Tg mice. The symptoms of gp130F759/F759 mice, including lymphoadenopathy, splenomegaly, hyper-γ-globulinemia, autoantibody production, increases in memory/activated T cells and granulocytes in the peripheral lymphoid organs, and a decrease in the class II MHCbright CD11c+ population, were augmented in the double mutants. Marked reductions in incidence, severity and immunological abnormalities were seen in the triple mutant, IL-6-/-/gp130F759/F759/pX-Tg, indicating that the arthritis in the double mutant is IL-6 dependent. gp130F759/F759/pX-Tg is a unique mouse model for RA..