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We have found that the administration of a diet containing 5% hydroxyapatite (HAP) derived from pig and cattle bones, and exposure to far-infrared rays (FIR) markedly inhibited spontaneous mammary tumorigenesis in SHN mice. Thus, the effect of combined treatment with HAP and FIR on mammary tumorigenesis was examined. The significant inhibition of tumor development by individual treatment with HAP or FIR was not enhanced by combined treatment; instead, the decrease in the inhibitory effect of HAP with age was ameliorated. Associated with this, life span was elongated and a decline in ovarian function was prevented by HAP plus FIR. Normal and preneoplastic growth of mammary glands and plasma component levels were not significantly affected by any treatment. The findings indicate that HAP and FIR have characteristics common to most natural products; in combination with other agents, they have little additive effect, when each is highly active. [ABSTRACT FROM AUTHOR]

The tissues are the site of many important immunological reactions, yet how the immune system is controlled at these sites remains opaque. Recent studies have identified Foxp3 + regulatory T (Treg) cells in non-lymphoid tissues with unique characteristics compared with lymphoid Treg cells. However, tissue Treg cells have not been considered holistically across tissues. Here, we performed a systematic analysis of the Treg cell population residing in non-lymphoid organs throughout the body, revealing shared phenotypes, transient residency, and common molecular dependencies. Tissue Treg cells from different non-lymphoid organs shared T cell receptor (TCR) sequences, with functional capacity to drive multi-tissue Treg cell entry and were tissue-agnostic on tissue homing. Together, these results demonstrate that the tissue-resident Treg cell pool in most non-lymphoid organs, other than the gut, is largely constituted by broadly self-reactive Treg cells, characterized by transient multi-tissue migration. This work suggests common regulatory mechanisms may allow pan-tissue Treg cells to safeguard homeostasis across the body., Competing Interests: Declaration of interests A.L. and J.D. are founders of Aila Biotech Ltd. A.L. has served on advisory boards for Imcyse, Sangamo, Dualyx, and Enhanc3D. C.P.R. is currently employed at CSL Behring. S.T. is currently employed at Roche. S.J. and A.B. are currently employed at Janssen Pharmaceuticals., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

This study investigates the neutralizing activity against the XBB1.5 variant and the ancestral strain in a population post-bivalent vaccination using a pseudo virus assay validated with authentic virus assay. While bivalent booster vaccination and past infections enhanced neutralization against the XBB 1.5 strain, individuals with comorbidities showed reduced responses. The study suggests the need for continuous vaccine updates to address emerging SARS-CoV-2 variants and highlights the importance of monitoring real-world immune responses., Competing Interests: MT received a grant from Pfizer Health Research Foundation for research not associated with this work. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhao, Tani, Makino-Okamura, Takita, Yamamoto, Kawahara, Abe, Sugiura, Yoshimura, Uchiyama, Yamazaki, Ishigame, Ueno, Okuma, Wakui, Fukuyama and Tsubokura.)

IL-31 receptor blockade suppresses pruritus of atopic dermatitis. However, cell-type-specific contributions of IL-31 receptor to itch, its expression mechanism, and the downstream signaling pathway to induce itch remain unknown. Here, using conditional knockout mice, we demonstrate that IL-31-induced itch requires sensory neuronal IL-31 receptor and STAT3. We find that IL-31 receptor expression is dependent on STAT3 in sensory neurons. In addition, pharmacological experiments suggest that STAT3 activation is important for the itch-inducing signaling downstream of the IL-31 receptor. A cutaneous IL-31 injection induces the nuclear accumulation of activated STAT3 first in sensory neurons that abundantly express IL-31 receptor and then in other itch-transmitting neurons. IL-31 enhances itch induced by various pruritogens including even chloroquine. Finally, pruritus associated with dermatitis is partially dependent on sensory neuronal IL-31 receptor and strongly on sensory neuronal STAT3. Thus, sensory neuronal STAT3 is essential for IL-31-induced itch and further contributes to IL-31-independent inflammatory itch., Competing Interests: Declaration of interests All authors declare that they have no relevant conflicts of interest., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

RNA vaccines based on lipid nanoparticles (LNPs) with in vitro transcribed mRNA (IVT-mRNA) encapsulated are now a currently successful but still evolving modality of vaccines. One of the advantages of RNA vaccines is their ability to induce CD8 + T-cell-mediated cellular immunity that is indispensable for excluding pathogen-infected cells or cancer cells from the body. In this study, we report on the development of LNPs with an enhanced capability for inducing cellular immunity by using an ionizable lipid with a vitamin E scaffold. An RNA vaccine that contained this ionizable lipid and an IVT-mRNA encoding a model antigen ovalbumin (OVA) induced OVA-specific cytotoxic T cell responses and showed an antitumor effect against an E.G7-OVA tumor model. Vaccination with the LNPs conferred protection against lethal infection by Toxoplasma gondii using its antigen TgPF. The vitamin E scaffold-dependent type I interferon response was important for effector CD8 + T cell differentiation induced by the mRNA-LNPs. Our findings also revealed that conventional dendritic cells (cDCs) were essential for achieving CD8 + T cell responses induced by the mRNA-LNPs, while the XCR1-positive subset of cDCs, cDC1 specialized for antigen cross-presentation, was not required. Consistently, the mRNA-LNPs were found to selectively transfect another subset of cDCs, cDC2 that had migrated from the skin to lymph nodes, where they could make vaccine-antigen-dependent contacts with CD8 + T cells. The findings indicate that the activation of innate immune signaling by the adjuvant activity of the vitamin E scaffold and the expression of antigens in cDC2 are important for subsequent antigen presentation and the establishment of antigen-specific immune responses.

Anaplastic lymphoma kinase (ALK)-positive histiocytosis is a rare emerging entity characterized by systemic or localized proliferation of histiocytes harboring ALK rearrangements. Breasts are reportedly affected by ALK-positive histiocytosis. Here, we evaluated 2 localized cases of breast ALK-positive histiocytosis through a comprehensive clinicopathologic, molecular, and genomic analysis to further delineate this entity and better understand its pathogenesis. The cases involved 2 undiagnosed ALK-positive spindle-cell breast lesions. Both cases were Asian women aged 30s to 40s who underwent excisions for asymptomatic breast masses. Macroscopically, both lesions were well-circumscribed, solid masses. Microscopically, both lesions were predominantly composed of fascicles with uniform, bland spindle cells, admixed with epithelioid histiocyte-like cells and lymphoid aggregates. Immunohistochemically, the spindle and epithelioid cells coexpressed ALK and histiocytic markers (eg, CD68, CD163). Genetically, both lesions harbored KIF5B-ALK, confirmed by fluorescence in situ hybridization and polymerase chain reaction-direct sequencing analyses. Combining these results, both cases were successfully diagnosed as ALK-positive histiocytosis. Furthermore, no common or previously annotated somatic alterations were identified by whole-exome sequencing. One case harbored clonal immunoglobulin gene rearrangements according to the polymerase chain reaction-based BIOMED-2 protocol. Therefore, ALK-positive histiocytosis can be accurately diagnosed through a combination of morphologic, immunohistochemical, and molecular analyses. In this entity, breast cases may have distinct clinicopathologic features: Asian women aged 30s to 40s, asymptomatic masses, and predominant spindled morphology. For pathogenesis, ALK rearrangements could be the driver alteration, and a subset of ALK-positive histiocytosis may harbor a lymphoid lineage. These findings can be utilized to improve the diagnosis of ALK-positive histiocytosis and better understand its pathogenesis., Competing Interests: Conflicts of Interest and Source of Funding: The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Recent clinical and experimental evidence has evoked the concept of the gut-brain axis to explain mutual interactions between the central nervous system and gut microbiota that are closely associated with the bidirectional effects of inflammatory bowel disease and central nervous system disorders 1-4 . Despite recent advances in our understanding of neuroimmune interactions, it remains unclear how the gut and brain communicate to maintain gut immune homeostasis, including in the induction and maintenance of peripheral regulatory T cells (pT reg cells), and what environmental cues prompt the host to protect itself from development of inflammatory bowel diseases. Here we report a liver-brain-gut neural arc that ensures the proper differentiation and maintenance of pT reg cells in the gut. The hepatic vagal sensory afferent nerves are responsible for indirectly sensing the gut microenvironment and relaying the sensory inputs to the nucleus tractus solitarius of the brainstem, and ultimately to the vagal parasympathetic nerves and enteric neurons. Surgical and chemical perturbation of the vagal sensory afferents at the hepatic afferent level reduced the abundance of colonic pT reg cells; this was attributed to decreased aldehyde dehydrogenase (ALDH) expression and retinoic acid synthesis by intestinal antigen-presenting cells. Activation of muscarinic acetylcholine receptors directly induced ALDH gene expression in both human and mouse colonic antigen-presenting cells, whereas genetic ablation of these receptors abolished the stimulation of antigen-presenting cells in vitro. Disruption of left vagal sensory afferents from the liver to the brainstem in mouse models of colitis reduced the colonic pT reg cell pool, resulting in increased susceptibility to colitis. These results demonstrate that the novel vago-vagal liver-brain-gut reflex arc controls the number of pT reg cells and maintains gut homeostasis. Intervention in this autonomic feedback feedforward system could help in the development of therapeutic strategies to treat or prevent immunological disorders of the gut.

The cytokines IL-17A and IL-17F have 50% amino-acid identity and bind the same receptor; however, their functional differences have remained obscure. Here we found that Il17f -/- mice resisted chemically induced colitis, but Il17a -/- mice did not, and that Il17f -/- CD45RB hi CD4 + T cells induced milder colitis in lymphocyte-deficient Rag2 -/- mice, accompanied by an increase in intestinal regulatory T cells (T reg cells). Clostridium cluster XIVa in colonic microbiota capable of inducing T reg cells was increased in both Il17f -/- mice and mice given transfer Il17f -/- T cells, due to decreased expression of a group of antimicrobial proteins. There was substantial production of IL-17F, but not of IL-17A, not only by naive T cells but also by various colon-resident cells under physiological conditions. Furthermore, antibody to IL-17F suppressed the development of colitis, but antibody to IL-17A did not. These observations suggest that IL-17F is an effective target for the treatment of colitis.

Protective immunity against pathogens depends on the efficient generation of functionally diverse effector and memory T lymphocytes. However, whether plasticity during effector-to-memory CD8 + T cell differentiation affects memory lineage specification and functional versatility remains unclear. Using genetic fate mapping analysis of highly cytotoxic KLRG1 + effector CD8 + T cells, we demonstrated that KLRG1 + cells receiving intermediate amounts of activating and inflammatory signals downregulated KLRG1 during the contraction phase in a Bach2-dependent manner and differentiated into all memory T cell linages, including CX 3 CR1 int peripheral memory cells and tissue-resident memory cells. "ExKLRG1" memory cells retained high cytotoxic and proliferative capacity distinct from other populations, which contributed to effective anti-influenza and anti-tumor immunity. Our work demonstrates that developmental plasticity of KLRG1 + effector CD8 + T cells is important in promoting functionally versatile memory cells and long-term protective immunity., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The relationship between methylation abnormality and autoimmune pancreatitis (AIP)-a representative IgG4-related disease-has not yet been elucidated. We identified SKI might have a significant methylation abnormality in AIP through methylation array analysis using the Illumina Infinium Human Methylation 450K BeadChip array, and investigated the relationship of SKI with AIP clinicopathological features. The methylation rate of SKI was assessed by quantitative SYBR green methylation-specific PCR, and the degree of SKI expression in tissue specimens was assessed by immunohistochemistry in 10 AIP cases, 14 cases of obstructive pancreatitis area in pancreatic ductal adenocarcinoma (PDA) without a history of AIP, and 9 normal pancreas (NP) cases. The SKI methylation ratio was significantly lower in AIP than in PDA and NP. Additionally, the immunohistochemical staining-index (SI) score for SKI was significantly higher in AIP than NP, although there was no significant difference between AIP and PDA. There was a strong negative correlation between SI score and SKI methylation ratio, and between the serum concentrations of IgG4 and the SKI methylation ratio. There was a moderate positive correlation between the serum concentrations of IgG4 and SI. SKI is thought to be an oncogene indicating that SKI hypomethylation and carcinogenesis might be linked to AIP. Furthermore, the correlation between serum concentrations of IgG4 and SKI methylation levels suggest SKI might be involved in the pathogenesis of AIP. However, the role of SKI has not been clearly elucidated. Further studies are needed to understand further the function of SKI., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Growing insight into the pathogenesis of autoimmune diseases and numerous studies in preclinical models highlights the potential of regulatory T cells to restore tolerance. By using non-obese diabetic (NOD) BDC2.5 TCR-transgenic (Tg), and IL-10 and Foxp3 double-reporter mice, we demonstrate that alteration of gut microbiota during cohousing experiments or treatment with anti-CD3 mAb significantly increase intestinal IL-10-producing type 1 regulatory T (Tr1) cells and decrease diabetes incidence. These intestinal antigen-specific Tr1 cells have the ability to migrate to the periphery via a variety of chemokine receptors such as CCR4, CCR5, and CCR7 and to suppress proliferation of Th1 cells in the pancreas. The ability of Tr1 cells to cure diabetes in NOD mice required IL-10 signaling, as Tr1 cells could not suppress CD4 + T cells with a dominant-negative IL-10R. Taken together, our data show a key role of intestinal Tr1 cells in the control of effector T cells and development of diabetes. Therefore, modulating gut-associated lymphoid tissue to boost Tr1 cells may be important in type 1 diabetes management., Competing Interests: The authors declare no conflict of interest.

Objectives: Autoimmune pancreatitis (AIP) is a representative IgG4-related and inflammatory disease of unknown etiology. To clarify mechanisms of carcinogenesis resulting from AIP, we focused on methylation abnormalities and KRAS mutations in AIP., Methods: Six tumor suppressor genes (NPTX2, Cyclin D2, FOXE1, TFPI2, ppENK, and p16) that exhibited hypermethylation in pancreatic carcinoma were selected for quantitative SYBR green methylation-specific polymerase chain reaction in 10 AIP specimens, 10 pancreatic adenocarcinoma cases without history of AIP containing carcinoma areas (CAs) and noncarcinoma areas (NCAs), and 11 normal pancreas (NP) samples. KRAS mutation in codons 12, 13, and 61 were also investigated using direct sequencing., Results: Hypermethylation events (≥10%) were identified in NPTX2, Cyclin D2, FOXE1, TFPI2, ppENK, and p16 in 1, 2, 2, 0, 2, and 0 CA cases, respectively, but not in these 6 candidate genes in AIP, NCA, and NP. However, the TFPI2 methylation ratio was significantly higher in AIP than NCA and NP. Direct sequencing results for KRAS showed no single-point mutations in AIP., Conclusions: These are the first studies characterizing methylation abnormalities in AIP. AIP's inflammatory condition may be related to carcinogenesis. Further study will elucidate methylation abnormalities associated with carcinogenesis in AIP.

Multiphoton imaging has been utilized to analyze in vivo immune cell dynamics over the last 15 years. Particularly, it has deepened the understanding of how immune responses are organized by immune cell migration and interactions. In this review, we first describe the following technical advances in recent imaging studies that contributed to the new findings on the regulation of immune responses and inflammation. Improved multicolor imaging of immune cell behavior has revealed that their interactions are spatiotemporally coordinated to achieve efficient and long-term immunity. The use of photoactivatable and photoconvertible fluorescent proteins has increased duration and volume of cell tracking, even enabling the analysis of inter-organ migration of immune cells. In addition, visualization of immune cell activation using biosensors for intracellular calcium concentration and signaling molecule activities has started to give further mechanistic insights. Then, we also introduce recent imaging analyses of interactions between immune cells and non-immune cells including endothelial, fibroblastic, epithelial, and nerve cells. It is argued that future imaging studies that apply updated technical advances to analyze interactions between immune cells and non-immune cells will be important for thorough physiological understanding of the immune system., Competing Interests: The authors declare that they have no competing interests.

The complement system is important for the host defence against infection as well as for the development of inflammatory diseases. Here we show that C1q/TNF-related protein 6 (CTRP6; gene symbol C1qtnf6) expression is elevated in mouse rheumatoid arthritis (RA) models. C1qtnf6(-/-) mice are highly susceptible to induced arthritis due to enhanced complement activation, whereas C1qtnf6-transgenic mice are refractory. The Arthus reaction and the development of experimental autoimmune encephalomyelitis are also enhanced in C1qtnf6(-/-) mice and C1qtnf6(-/-) embryos are semi-lethal. We find that CTRP6 specifically suppresses the alternative pathway of the complement system by competing with factor B for C3(H2O) binding. Furthermore, treatment of arthritis-induced mice with intra-articular injection of recombinant human CTRP6 cures the arthritis. CTRP6 is expressed in human synoviocytes, and CTRP6 levels are increased in RA patients. These results indicate that CTRP6 is an endogenous complement regulator and could be used for the treatment of complement-mediated diseases.

Interleukin-17 (IL-17)-producing γδ T (γδ17) cells have been implicated in inflammatory diseases, but the underlying pathogenic mechanisms remain unclear. Here, we show that both CD4(+) and γδ17 cells are required for the development of autoimmune arthritis in IL-1 receptor antagonist (IL-1Ra)-deficient mice. Specifically, activated CD4(+) T cells direct γδ T-cell infiltration by inducing CCL2 expression in joints. Furthermore, IL-17 reporter mice reveal that the Vγ6(+) subset of CCR2(+) γδ T cells preferentially produces IL-17 in inflamed joints. Importantly, because IL-1Ra normally suppresses IL-1R expression on γδ T cells, IL-1Ra-deficient mice exhibit elevated IL-1R expression on Vγ6(+) cells, which play a critical role in inducing them to produce IL-17. Our findings demonstrate a pathogenic mechanism in which adaptive and innate immunity induce an autoimmune disease in a coordinated manner.

Allergic contact dermatitis (ACD) is a typical occupational disease in industrialized countries. Although various cytokines and chemokines are suggested to be involved in the pathogenesis of ACD, the roles of these molecules remain to be elucidated. CC chemokine receptor 8 (CCR8) is one such molecule, of which expression is up-regulated in inflammatory sites of ACD patients. In this study, we found that Ccr8(-/-) mice developed severer contact hypersensitivity (CHS) responses to 2,4-dinitrofluorobenzene, a murine model of ACD, compared with wild-type mice. T cells from Ccr8(-/-) mice showed enhanced proliferative recall responses and Th1 and Th17 cell populations were expanded in these mice. However, CHS responses were similar between SCID mice adoptively transferred with Ccr8(-/-) and wild-type T cells, suggesting that CCR8 in T cells is not responsible for the exacerbation of CHS. Notably, skin-resident dendritic cells (DCs), such as Langerhans cells and dermal DCs, and inflammatory DCs were highly accumulated in lymph nodes (LNs) of Ccr8(-/-) mice after sensitization. Consistent with this, Ccr8(-/-) antigen-presenting cells readily migrated from the skin to the draining LNs after sensitization. These observations suggest that CCR8 negatively regulates migration of cutaneous DCs from the skin to the draining LNs in CHS by keeping these cells in the skin., (© The Japanese Society for Immunology. 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Meningiomas show a diverse histopathologic appearance, often referred to as metaplastic changes; however, adenocarcinoma-like metaplasia is an extremely rare condition. Here, we present a novel case. A dura-based bulky mass located in the right frontotemporal region was identified radiologically in an 83-year-old woman. The tumor, yellow to ash-gray in color, was subtotally removed. Histopathological examination revealed robust adenocarcinoma-like structures within a conventional meningothelial neoplasm. Meningioma elements showed a WHO grade I to III histology. Morphological and immunophenotypic transition between meningothelial and columnar epithelial cells was confirmed on detailed observation. It was of note that the adenocarcinomatous components shared an immunophenotype with intestinal epithelium, expressing CDX2, MUC2 and cytokeratin 20. The present case could be differentiated from secretory meningioma based on distinct cellular atypia, lack of intracytoplasmic lumina and pseudosammoma bodies, and the intact status of the KLF4 gene. In addition, the morphological and immunophenotypic transition excluded the possibility of metastatic carcinoma within meningioma. This is the first reported case of meningioma with adenocarcinoma-like metaplasia harboring an intestinal immunophenotype., (© 2014 Japanese Society of Neuropathology.)

Type 2 inflammatory cytokines, including interleukin-4 (IL-4), IL-5, IL-9, and IL-13, drive the characteristic features of immunity against parasitic worms and allergens. Whether IL-9 serves an essential role in the initiation of host-protective responses is controversial, and the importance of IL-9- versus IL-4-producing CD4⁺ effector T cells in type 2 immunity is incompletely defined. Herein, we generated IL-9-deficient and IL-9-fluorescent reporter mice that demonstrated an essential role for this cytokine in the early type 2 immunity against Nippostrongylus brasiliensis. Whereas T helper 9 (Th9) cells and type 2 innate lymphoid cells (ILC2s) were major sources of infection-induced IL-9 production, the adoptive transfer of Th9 cells, but not Th2 cells, caused rapid worm expulsion, marked basophilia, and increased mast cell numbers in Rag2-deficient hosts. Taken together, our data show a critical and nonredundant role for Th9 cells and IL-9 in host-protective type 2 immunity against parasitic worm infection., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Inflammatory and anti-inflammatory cytokines play an important role in the generation of effector and memory CD8(+) T cells. We used two different models, transgenic expression of truncated (dominant negative) form of TGF-βRII (dnTGFβRII) and Cre-mediated deletion of the floxed TGF-βRII to examine the role of TGF-β signaling in the formation, function, and homeostatic proliferation of memory CD8(+) T cells. Blocking TGF-β signaling in effector CD8(+) T cells using both of these models demonstrated a role for TGF-β in regulating the number of short-lived effector cells but did not alter memory CD8(+) T cell formation and their function upon Listeria monocytogenes infection in mice. Interestingly, however, a massive lymphoproliferative disorder and cellular transformation were observed in Ag-experienced and homeostatically generated memory CD8(+) T cells only in cells that express the dnTGFβRII and not in cells with a complete deletion of TGF-βRII. Furthermore, the development of transformed memory CD8(+) T cells expressing dnTGFβRII was IL-7- and IL-15-independent, and MHC class I was not required for their proliferation. We show that transgenic expression of the dnTGFβRII, rather than the absence of TGF-βRII-mediated signaling, is responsible for dysregulated expansion of memory CD8(+) T cells. This study uncovers a previously unrecognized dominant function of the dnTGFβRII in CD8(+) T cell proliferation and cellular transformation, which is caused by a mechanism that is different from the absence of TGF-β signaling. These results should be considered during both basic and translational studies where there is a desire to block TGF-β signaling in CD8(+) T cells.

TGF-β signaling in T cells is critical for peripheral T-cell tolerance by regulating effector CD4(+) T helper (Th) cell differentiation. However, it is still controversial to what extent TGF-β signaling in Foxp3(+) regulatory T (Treg) cells contributes to immune homeostasis. Here we showed that abrogation of TGF-β signaling in thymic T cells led to rapid type 1 diabetes (T1D) development in NOD mice transgenic for the BDC2.5 T-cell receptor. Disease development in these mice was associated with increased peripheral Th1 cells, whereas Th17 cells and Foxp3(+) Treg cells were reduced. Blocking of IFN-γ signaling alone completely suppressed diabetes development in these mice, indicating a critical role of Th1 cells in this model. Furthermore, deletion of TGF-β signaling in peripheral effector CD4(+) T cells, but not Treg cells, also resulted in rapid T1D development, suggesting that conventional CD4(+) T cells are the main targets of TGF-β to suppress T1D. TGF-β signaling was dispensable for Treg cell function, development, and maintenance, but excessive IFN-γ production due to the absence of TGF-β signaling in naive CD4(+) T cells indirectly caused dysregulated Treg cell homeostasis. We further showed that T cell-derived TGF-β1 was critical for suppression of Th1 cell differentiation and T1D development. These results indicate that autocrine/paracrine TGF-β signaling in diabetogenic CD4(+) T cells, but not Treg cells, is essential for controlling T1D development.

Interleukin-17A (IL-17A) is the signature cytokine of the recently identified T helper 17 (Th17) cell subset. IL-17 has six family members (IL-17A to IL-17F). Although IL-17A and IL-17F share the highest amino acid sequence homology, they perform distinct functions; IL-17A is involved in the development of autoimmunity, inflammation, and tumors, and also plays important roles in the host defenses against bacterial and fungal infections, whereas IL-17F is mainly involved in mucosal host defense mechanisms. IL-17E (IL-25) is an amplifier of Th2 immune responses. The functions of IL-17B, IL-17C, and IL-17D remain largely elusive. In this review, we describe the identified functions of each IL-17 family member and discuss the potential of these molecules as therapeutic targets., (Copyright © 2011 Elsevier Inc. All rights reserved.)

IL-1 is a proinflammatory cytokine consisting of two molecular species, IL-1alpha and IL-1beta, and IL-1R antagonist (gene: Il1rn) is the endogenous suppressor. Il1rn(-/-) mice spontaneously develop autoimmune diseases, such as arthritis and aortitis, and a dermatitis that histologically resembles human psoriasis. The pathogenic mechanisms underlying this dermatitis, however, remain to be elucidated. In this study, we demonstrated that the production of inflammatory cytokines and chemokines was enhanced at the site of inflammation. The development of dermatitis was completely suppressed in Tnfsf1a(-/-) but not in Il6(-/-) mice, similar to that observed in arthritis and aortitis. However, IL-17 deficiency did not affect the development of dermatitis at all, in clear contrast to that of arthritis and aortitis. Different from arthritis and aortitis, adoptive transfer of Il1rn(-/-) T cells did not induce dermatitis in the recipient SCID mice and skin lesions developed in Il1rn(-/-) SCID mice, indicating that T cells are not involved in the development of skin lesions. In support for this, bone marrow cell transplantation experiments showed that TNF produced by skin residential cells, but not bone marrow cell-derived cells, was important for the development of dermatitis. Furthermore, we showed that IL-1 directly enhanced TNF and chemokine expression in keratinocytes. These observations suggest that excess IL-1 signaling directly activates keratinocytes to produce TNF and chemokines, resulting in the development of psoriasis-like skin lesions without the involvement of autoimmunity in Il1rn(-/-) mice.

Dectin-2 (gene symbol Clec4n) is a C-type lectin expressed by dendritic cells (DCs) and macrophages. However, its functional roles and signaling mechanisms remain to be elucidated. Here, we generated Clec4n(-/-) mice and showed that this molecule is important for host defense against Candida albicans (C. albicans). Clec4n(-/-) DCs had virtually no fungal alpha-mannan-induced cytokine production. Dectin-2 signaling induced cytokines through an FcRgamma chain and Syk-CARD9-NF-kappaB-dependent signaling pathway without involvement of MAP kinases. The yeast form of C. albicans induced interleukin-1beta (IL-1beta) and IL-23 secretion in a Dectin-2-dependent manner. In contrast, cytokine production induced by the hyphal form was only partially dependent on this lectin. Both yeast and hyphae induced Th17 cell differentiation, in which Dectin-2, but not Dectin-1, was mainly involved. Because IL-17A-deficient mice were highly susceptible to systemic candida infection, this study suggests that Dectin-2 is important in host defense against C. albicans by inducing Th17 cell differentiation., (Copyright 2010 Elsevier Inc. All rights reserved.)

A 60-year-old woman was referred for evaluation of a cystic mass in the pancreatic body that extended to the tail. Transabdominal ultrasonography demonstrated an oval cystic mass 24 cm in diameter, filled with debris. On the cyst wall there was a wide-based, smooth-surfaced, heterogeneous high-echoic protrusion that was 5 cm in diameter. On CT the protrusion showed internal enhancement. Endoscopic pancreatography showed no intraductal mucin or communication with the cyst. A distal pancreatectomy was performed under the diagnosis of mucinous cystadenocarcinoma. Grossly there was a brownish, hemispherical protrusion into the thin monolocular cyst. The cut surface of the protrusion showed a peripheral yellow-brownish area and an internal wine-colored area. Histopathologically the cyst wall consisted of tall columnar cells without atypical nuclei, ovarian-type stroma beneath the epithelium, and fibrotic tissue with abundant capillary vessels, suggestive of a mucinous cystadenoma. The protrusion was composed of peripheral organized hematoma without a covering epithelium, and internal hemorrhage and many capillary vessels, with no evidence of tumor cell necrosis. These histopathological findings appear to be similar to those of chronic expanding hematoma. The formation of a huge mural hematoma in a mucinous cystic neoplasm can occur as a repair process after the breaking of intrawall vessels.

A 78-year-old male with lumbar pain and dim consciousness presented the clinical pictures of plasma cell leukemia (PCL) producing a large amount of monoclonal immunoglobulin E (IgE)/kappa protein. Laboratory investigation demonstrated an elevated serum calcium level and renal dysfunction. Systemic bone X-ray survey disclosed only a solitary osteolytic lesion. Circulating plasma cells demonstrated CD19(-)/CD56(-) and MPC-1(-)/CD49e(-)/CD45(+/-), the latter indicating the immature phenotype of the tumor cells. Bone marrow was occupied with immature, atypical plasma cells, of which cytoplasms were positive for IgE by direct immunofluorescence analysis. Chromosomes revealed a translocation of (11;14)(q13;q32), which is concordant with cyclinD1-protein overexpression by immunohistochemistry. He was treated with dexamethasone and vincristine, which somewhat improved the laboratory findings. He died of tumor progression after 4-month admission. The clinical and biological characteristics of IgE-producing PCL, a very rare type of plasma cell dyscrasia, are discussed, reviewing the past literature.

Interleukin-17A (IL-17A) is a cytokine produced by T helper 17 (Th17) cells and plays important roles in the development of inflammatory diseases. Although IL-17F is highly homologous to IL-17A and binds the same receptor, the functional roles of this molecule remain largely unknown. Here, we demonstrated with Il17a(-/-), Il17f(-/-), and Il17a(-/-)Il17f(-/-) mice that IL-17F played only marginal roles, if at all, in the development of delayed-type and contact hypersensitivities, autoimmune encephalomyelitis, collagen-induced arthritis, and arthritis in Il1rn(-/-) mice. In contrast, both IL-17F and IL-17A were involved in host defense against mucoepithelial infection by Staphylococcus aureus and Citrobacter rodentium. IL-17A was produced mainly in T cells, whereas IL-17F was produced in T cells, innate immune cells, and epithelial cells. Although only IL-17A efficiently induced cytokines in macrophages, both cytokines activated epithelial innate immune responses. These observations indicate that IL-17A and IL-17F have overlapping yet distinct roles in host immune and defense mechanisms.

T-helper 17 (Th17) cells are a newly discovered CD4(+) helper T-cell subset that produces interleukin-17A (IL-17A) and IL-17F. IL-17A plays important roles in allergic responses such as delayed-type hypersensitivity, contact hypersensitivity, and allergic airway inflammation. IL-17A promotes inflammation by inducing various proinflammatory cytokines and chemokines, recruiting neutrophils, enhancing antibody production, and activating T cells. IL-17A expression is also augmented in autoimmune diseases such as multiple sclerosis and rheumatoid arthritis. Using mouse models of these diseases, we found that IL-17A plays a central role in their development. IL-6 is required for the development of Th17 cells and tumor necrosis factor functions downstream of IL-17A during the effector phase. IL-1 is important both for developing Th17 cells and eliciting inflammation. Th17 cells, like Th1 and Th2 cells, are involved in host defense against infections, but the contribution of these Th subsets to defense mechanisms differs among pathogens. The roles of IL-17F remain largely unknown. In this review, we introduce how IL-17A/IL-17F are involved in inflammatory immune responses and host defense mechanisms and discuss their relationship with other cytokines in the development of inflammatory and infectious diseases.

We propose a novel role for interleukin (IL) 6 in inducing rapid spontaneous proliferation (SP) of naive CD8(+) T cells, which is a crucial step in the differentiation of colitogenic CD8(+) T cells. Homeostasis of T cells is regulated by two distinct modes of cell proliferation: major histocompatibility complex/antigen-driven rapid SP and IL-7/IL-15-dependent slow homeostatic proliferation. Using our novel model of CD8(+) T cell-dependent colitis, we found that SP of naive CD8(+) T cells is essential for inducing pathogenic cytokine-producing effector T cells. The rapid SP was predominantly induced in mesenteric lymph nodes (LNs) but not in peripheral LNs under the influence of intestinal flora and IL-6. Indeed, this SP was markedly inhibited by treatment with anti-IL-6 receptor monoclonal antibody (IL-6R mAb) or antibiotic-induced flora depletion, but not by anti-IL-7R mAb and/or in IL-15-deficient conditions. Concomitantly with the inhibition of SP, anti-IL-6R mAb significantly inhibited the induction of CD8(+) T cell-dependent autoimmune colitis. Notably, the transfer of naive CD8(+) T cells derived from IL-17(-/-) mice did not induce autoimmune colitis. Thus, we conclude that IL-6 signaling is crucial for SP under lymphopenic conditions, which subsequently caused severe IL-17-producing CD8(+) T cell-mediated autoimmune colitis. We suggest that anti-IL-6R mAb may become a promising strategy for the therapy of colitis.

This report describes serial observations of the growth process of a small invasive ductal carcinoma (IDC) of the pancreas from imaging studies. Histopathological studies showed IDC with macroscopic retention cysts proximal to an intraductal papillary-mucinous adenoma with mild atypia of the branch duct type in the pancreatic body, with no relation between the two lesions. IDC was demonstrated as an extremely low-echoic mass resembling a cyst with an unclear margin on the initial endoscopic ultrasonography. We misinterpreted the low-echoic mass as a benign intraductal mucinous-papillary neoplasm (IPMN) based on findings of other imaging studies, and the patient was followed-up. The mass increased from 7 mm to 13 mm in diameter over 22 mo, and remained smaller than 10 mm in diameter for about 420 d. The tumor volume doubling time was 252 d. The Ki67 labeling index was 15.9%, similar to that described in previous reports. Hence, IDC may grow slowly while remaining small.

An 84-year-old man, who was being followed up after lobectomy for lung carcinoma, was referred for evaluation of a dilated main pancreatic duct (MPD) from the body to the tail. Endoscopic ultrasonography demonstrated a low-echo mass occupying the MPD from the body to the tail. Endoscopic retrograde pancreatography showed an occlusion of the MPD in the body, and brush cytology indicated malignant cells. Distal pancreatectomy was performed. Grossly, a white-yellow, irregular-shaped solid mass without macroscopic mucus filled the lumen of the MPD. Histologically, the mass consisted of a complex fusion of tubular glands with atypical nuclei, which did not have intracellular mucus and oncocytic cytoplasm. The tumor mass showed abrupt transition to the normal epithelium. Immunohistochemically the tumor cells were partially positive for mucin 1 (MUC1) and MUC6, and negative for MUC2, MUC5AC, and lipase. Unfortunately the patient died of brain metastasis from lung carcinoma 15 months later. A review of reported cases of intraductal tubular tumors of the pancreas showed that the present case involved characteristics and immunohistochemical staining pattern similar to those of intraductal tubular carcinoma, although it might not be described as a typical intraductal tubular carcinoma under the existing Japanese rules.

Aims: To investigate the distribution of intraductal lesions in small invasive ductal carcinoma (IDC) of the pancreas., Methods: In 21 cases with IDCs microscopically < or = 20 mm in diameter, the intraductal lesions around a mass were studied histologically and mapped according to the pancreatic intraepithelial neoplasia (PanIN) classification., Results: PanIN-3, PanIN-2, PanIN-1B and PanIN-1A were found in 17, 10, 20 and 21 of 21 cases, respectively, and were divided into lesions in adjacent and distal areas, respectively defined as within and beyond 10 mm from the mass as follows: 100% (17/17), 100% (10/10), 95.0% (19/20) and 90.5% (19/21) in the former, while 23.5% (4/17), 50.0% (5/10), 90.0% (18/20) and 95.2% (20/21) in the latter. PanIN-3 lesions were predominantly found in the area adjacent to the mass. In some cases, significant PanIN-3 appeared to show a consecutive geographic extension around the mass via the main pancreatic duct (MPD). The distance of PanIN-3 spread was within 25 (mean 10.5) mm from the mass edge. PanIN-2 lesions were found in the area adjacent to the mass and discontinuous with the mass or PanIN-3 lesions. PanIN-1B and PanIN-1A tended mainly to exist sporadically throughout the entire pancreas. In the MPD, PanIN-3 was found in 14 (82.4%) of 17 cases and in 36 (32.1%) of 112 lesions, which was most frequent in intraductal lesions., Conclusions: PanIN-3 lesions might be an intraductal extension of the main tumor. The resection margin of 25 mm, at least longer than 11 mm, from the mass edge will be necessary., (2007 S. Karger AG, Basel and IAP)

IL-17 is a proinflammatory cytokine that activates T cells and other immune cells to produce a variety of cytokines, chemokines, and cell adhesion molecules. This cytokine is augmented in the sera and/or tissues of patients with contact dermatitis, asthma, and rheumatoid arthritis. We previously demonstrated that IL-17 is involved in the development of autoimmune arthritis and contact, delayed, and airway hypersensitivity in mice. As the expression of IL-17 is also augmented in multiple sclerosis, we examined the involvement of this cytokine in these diseases using IL-17(-/-) murine disease models. We found that the development of experimental autoimmune encephalomyelitis (EAE), the rodent model of multiple sclerosis, was significantly suppressed in IL-17(-/-) mice; these animals exhibited delayed onset, reduced maximum severity scores, ameliorated histological changes, and early recovery. T cell sensitization against myelin oligodendrocyte glycoprotein was reduced in IL-17(-/-) mice upon sensitization. The major producer of IL-17 upon treatment with myelin digodendrocyte glycopritein was CD4+ T cells rather than CD8+ T cells, and adoptive transfer of IL-17(-/-) CD4+ T cells inefficiently induced EAE in recipient mice. Notably, IL-17-producing T cells were increased in IFN-gamma(-/-) cells, while IFN-gamma-producing cells were increased in IL-17(-/-) cells, suggesting that IL-17 and IFN-gamma mutually regulate IFN-gamma and IL-17 production. These observations indicate that IL-17 rather than IFN-gamma plays a crucial role in the development of EAE.

IL-23 induces the differentiation of naive CD4(+) T cells into highly pathogenic helper T cells (Th17/Th(IL-17)) that produce IL-17, IL-17F, IL-6, and TNF-alpha, but not IFN-gamma and IL-4. Two studies in this issue of the JCI demonstrate that blocking IL-23 or its downstream factors IL-17 and IL-6, but not the IL-12/IFN-gamma pathways, can significantly suppress disease development in animal models of inflammatory bowel disease and MS (see the related articles beginning on pages 1310 and 1317). These studies suggest that the IL-23/IL-17 pathway may be a novel therapeutic target for the treatment of chronic inflammatory diseases.

The effects of passive immunoneutralization of endogenous inhibin on ovulation rate in immature rats were investigated. Efficiency of superovulation on production of fertilized oocytes was compared between the inhibin antiserum (inhibin-AS) and equine chorionic gonadotropin (eCG) protocols. Immature female Wistar strain rats were superovulated with a single injection of 100-200 microl inhibin-AS, with and without an injection of human chorionic gonadotropin (hCG). A total of 77.8% of the 26-30-day-old rats treated with a single injection of 100-200 microl inhibin-AS ovulated 72 h after treatment, while rats given normal goat serum (NGS; 200 microl) did not ovulate. At 28 days of age, all of the inhibin-AS treated rats ovulated when additional hCG treatment was given, whereas the number of ovulated oocytes was not affected. The number of ovulated oocytes in the inhibin-AS-hCG treated groups was significantly higher than that of the NGS-hCG treated group. In addition, plasma concentrations of FSH in the inhibin-AS-hCG treated group significantly increased compared with the NGS treated group. While the percentage of mated rats in the 200 microl inhibin-AS-hCG treated group was significantly lower than that of the 15 IU eCG-hCG treated group, the fertilization rate was comparable between the two groups. The number of fertilized oocytes in the 200 microl inhibin-AS-hCG treated group was significantly higher in comparison with the 15 IU eCG-hCG treated group. These results suggest that immunoneutralization of endogenous inhibin could be a reliable method for induction of superovulation to collect a large number of normally fertilized oocytes in immature rats.

The present study was undertaken to investigate the effects of passive immunoneutralization of endogenous inhibin on ovulation rate and embryo development in vivo and in vitro to establish a new alternative superovulation method in the adult rat. Female adult rats of Wistar strain were superovulated with a single injection of inhibin antiserum (inhibin-AS; 100 or 400 microl) or an injection of 20 IU eCG followed by an injection of 10 IU hCG. Untreated animals served as controls. Embryos were collected from oviducts or uteri on Days 1-5 of pregnancy, and the number of embryos and implantation sites were observed. On Day 1 of pregnancy, the two-cell-stage embryos were cultured and embryos from the 100-microl inhibin-AS group and the control group were transferred to recipient females to determine developmental competence. There were no significant differences between groups in fertilization rate. The numbers of normal embryos in the inhibin-AS-treated groups were significantly higher than the control and the eCG-hCG-treated groups throughout Days 1-4 of pregnancy. The number of implantation sites observed on Day 5 of pregnancy in the inhibin-AS-treated groups was significantly higher than both the control and the eCG-hCG-treated groups. Furthermore, the rate of blastocyst development in vitro in the inhibin-AS-treated groups and posttransfer viability in the 100-microl-inhibin-AS group were comparable with those of the control group. These results indicate that immunoneutralization of endogenous inhibin is a new practical alternative for induction of superovulation as a substitution for eCG-hCG method in the adult rat.

Purpose: To report the relation between CT findings and the grade of malignancy in gastrointestinal stromal tumor (GIST), especially the uncommitted type of GIST., Materials and Methods: A total of 14 patients with histologically proven GIST (uncommitted type) underwent CT. Tumors were divided into three grades. HISTOLOGICALLY: Benign (mitotic index [MI] < 2/10 high-power fields [HPF]), borderline (2/10 HPF < or = MI < or = 5/10 HPF), and malignant (5/10 HPF < MI). We evaluated tumor size, cystic component, margin, and early enhancement., Results: All benign tumors were smaller than 5 cm, and most malignant tumors reached 5 cm. The size of borderline tumors was between the sizes of benign and malignant tumors. No benign tumors had cystic components, whereas all borderline and malignant tumors except for one case had cystic components. Only two huge malignant tumors had unclear margins. The relation between early enhancement and the grade of malignancy showed no tendency, but all duodenal tumors showed marked early enhancement irrespective of grade., Conclusion: The grade of malignancy of GIST (uncommitted type) and size, presence of cystic components, and margin were highly correlated. That is, 1) tumors smaller than 5 cm with no cystic components can be diagnosed as benign, whereas 2) tumors that have cystic components are borderline or malignant. 3) Tumors that have cystic components and unclear margin can be diagnosed as actively malignant.

The effects on spontaneous motor activity of the pattern of restricted feeding, far-infrared ray (FIR) irradiation or free access in drinking water containing Sasa Health, a bamboo grass leafextract, were examined in SHN male mice at 2-3 months of age. In mice whose diet was restricted to 60% of the control, fed at 9:00 or 17:00 hours, the level of spontaneous behaviour was elevated 1 hour before the respective feeding time (8:00 or 16:00 hours). The activity was stimulated by FIR in both the control and food-restricted mice, but to a much higher degree in the latter. Treatment with Sasa Health in drinking water lowered the elevated activity level in food-restricted mice. Plasma component levels and organ weights were modulated by FIR or Sasa Health. The findings revealed that, not only the restricted feeding itsel, but also its pattern, significantly affected behaviour and that FIR and Sasa Health modified the deleterious effects of restricted feeding.