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Epstein-Barr virus-induced gene 3 (EBI3) is a subunit commonto IL-27, IL-35, and IL-39. Here, we explore an intracellular role of EBI3 that is independent of its function In cytokines. EBI3-deflclent naive [CD4.sup.+] T cells had reduced IFN-[gamma] production and failed to induce T cell-dependent colitis in mice. Similarly reduced IFN-[gamma] production was observed In vitro in EBI3-deficient [CD4.sup.+] T cells differentiated under pathogenic Th17 polarizing conditions with IL-23. This is because the induction of expression of one of the IL-23 receptor (IL-23R) subunits, IL-23R[alpha], but not another IL-23R subunit, IL-12R[beta]1, was selectively decreased at the protein level, but not the mRNA level. EBI3 augmented IL-23R[alpha] expression via bindingto the chaperone molecule calnexin and to IL-23R[alpha] in a peptide-dependent manner, but not a glycan-dependent manner. Indeed, EBI3 failed to augment IL-23R[alpha] expression in the absence of endogenous calnexin. Moreover, EBI3 poorly augmented the expression of C149R, an IL-23R[alpha] variant that protects against the development of human colitis, because binding of EBI3 to the variant was reduced. Taken together with the result that EBI3 expression Is Inducible InT cells, the present results suggest that EBI3 plays a critical role in augmenting IL-23R[alpha] protein expression via calnexin under inflammatory conditions., Introduction Cytokines of the IL-12 family play critical roles in regulating the differentiation of Th cells and their effector functions (1). These cytokines are composed of 2 distinct subunits forming [...]

Acute liver failure (ALF) is a life-threatening condition, and liver transplantation is the only therapeutic option. Although immune dysregulation is central to its pathogenesis, the precise mechanism remains unclear. Here, we show that the number of peripheral and hepatic plasmacytoid DCs (pDCs) decrease during acute liver injury in both humans and mice. Selective depletion of pDCs in [Siglech.sup.dtr/+] mice exacerbated concanavalin A-induced acute liver injury. In contrast, adoptively transferred BM-derived pDCs preferentially accumulated in the inflamed liver and protected against liver injury. This protective effect was independent of TLR7 and TLR9 signaling, since a similar effect occurred following transfer of MyD88-deficient pDCs. Alternatively, we found an unexpected immunosuppressive role of pDCs in an IL-35-dependent manner. Both Il12a and Ebi3, heterodimeric components of IL-35, were highly expressed in transferred pDCs and [CD4.sup.+][CD25.sup.+] Tregs. However, the protective effect of pDC transfer was completely lost in mice depleted of Tregs by anti-CD25 antibody. Moreover, pDCs derived from IL-35-deficient mice had less of a protective effect both in vivo and in vitro even in the presence of Tregs. These results highlight a unique aspect of pDCs in association with Tregs, serving as a guide for immunotherapeutic options in ALF., Introduction Acute liver failure (ALF) is a life-threatening condition characterized by progressive and extensive multilobular damage of the hepatocytes and massive intrahepatic infiltration of immune cells. However, there are no [...]

This document, titled "State-of-the-Art Cancer Immunotherapies," provides an overview of recent advancements in cancer immunotherapy. It discusses the use of adoptive cell transfer (ACT) of chimeric antigen receptor (CAR)-T cells and immune checkpoint inhibitors (ICIs) as effective treatments for cancer. The document also highlights the potential of mRNA vaccines delivered by lipid nanoparticles (LNPs) in cancer treatment. Additionally, it explores the role of cytokines and exosomes in cancer immunotherapy. The authors suggest that these advancements deepen our understanding of human cancer and offer potential strategies for its eradication. [Extracted from the article]

Cell transfer therapy using mesenchymal stem cells (MSCs) has pronounced therapeutic potential, but concerns remain about immune rejection, emboli formation, and promotion of tumor progression. Because the mode of action of MSCs highly relies on their paracrine effects through secretion of bioactive molecules, cell‐free therapy using the conditioned medium (CM) of MSCs is an attractive option. However, the effects of MSC‐CM on tumor progression have not been fully elucidated. Herein, we addressed this issue and investigated the possible underlying molecular mechanisms. The CM of MSCs derived from human bone marrow greatly inhibited the in vitro growth of several human tumor cell lines and the in vivo growth of the SCCVII murine squamous cell carcinoma cell line with reduced neovascularization. Exosomes in the MSC‐CM were only partially involved in the inhibitory effects. The CM contained a variety of cytokines including insulin‐like growth factor binding proteins (IGFBPs). Among them, IGFBP‐4 greatly inhibited the in vitro growth of these tumors and angiogenesis, and immunodepletion of IGFBP‐4 from the CM significantly reversed these effects. Of note, the CM greatly reduced the phosphorylation of AKT, ERK, IGF‐1 receptor beta, and p38 MAPK in a partly IGFBP4‐dependent manner, possibly through its binding to IGF‐1/2 and blocking the signaling. The CM depleted of IGFBP‐4 also reversed the inhibitory effects on in vivo tumor growth and neovascularization. Thus, MSC‐CM has potent inhibitory effects on tumor growth and neovascularization in an IGFBP4‐dependent manner, suggesting that cell‐free therapy using MSC‐CM could be a safer promising alternative for even cancer patients. [ABSTRACT FROM AUTHOR]

Current worldwide mRNA vaccination against SARS-CoV-2 by intramuscular injection using a needled syringe has greatly protected numerous people from COVID-19. An intramuscular injection is generally well tolerated, safer and easier to perform on a large scale, whereas the skin has the benefit of the presence of numerous immune cells, such as professional antigen-presenting dendritic cells. Therefore, intradermal injection is considered superior to intramuscular injection for the induction of protective immunity, but more proficiency is required for the injection. To improve these issues, several different types of more versatile jet injectors have been developed to deliver DNAs, proteins or drugs by high jet velocity through the skin without a needle. Among them, a new needle-free pyro-drive jet injector has a unique characteristic that utilizes gunpower as a mechanical driving force, in particular, bi-phasic pyrotechnics to provoke high jet velocity and consequently the wide dispersion of the injected DNA solution in the skin. A significant amount of evidence has revealed that it is highly effective as a vaccinating tool to induce potent protective cellular and humoral immunity against cancers and infectious diseases. This is presumably explained by the fact that shear stress generated by the high jet velocity facilitates the uptake of DNA in the cells and, consequently, its protein expression. The shear stress also possibly elicits danger signals which, together with the plasmid DNA, subsequently induces the activation of innate immunity including dendritic cell maturation, leading to the establishment of adaptive immunity. This review summarizes the recent advances in needle-free jet injectors to augment the cellular and humoral immunity by intradermal injection and the possible mechanism of action. [ABSTRACT FROM AUTHOR]

Simple Summary: Allergic, inflammatory, or autoimmune diseases are characterized by exaggerated immune responses to harmless proteins such as pollen, dust mites, and foods in the environment or self-proteins. The number of cases has increased over the last 50 years. This is considered to be related to reduced exposure to pathogenic microorganisms, as well as a revolutionary rise in exposure to dietary chemicals and drugs via processed food, formula milk, preservatives, and antibiotics, presumably resulting in the breakdown of immune tolerance to proteins. Such chemicals and drugs may work as haptens, which are small molecules that only elicit an immune response when bound to proteins. Indeed, accumulating evidence revealed the involvement of haptens in the development of various autoimmune-like diseases, such as allergic, inflammatory, or autoimmune diseases including allergic contact dermatitis, atopy, asthma, food allergy, inflammatory bowel diseases, hemolytic anemia, liver injury, leukoderma, and even antitumor immunity. This review highlights recent advances in the chemical- and drug-induced development of these autoimmune-like diseases via haptenation together with possible molecular mechanisms and in vitro testing alternatives to evaluate in advance whether a substance might lead to the development of these diseases. Haptens are small molecules that only elicit an immune response when bound to proteins. Haptens initially bind to self-proteins and activate innate immune responses by complex mechanisms via inflammatory cytokines and damage-associated molecular patterns and the subsequent upregulation of costimulatory signals such as cluster of differentiation 86 (CD86) on dendritic cells. Subsequent interactions between CD86 and CD28 on T cells are critically important for properly activating naive T cells and inducing interleukin 2 production, leading to the establishment of adaptive immunity via effector and memory T cells. Accumulating evidence revealed the involvement of haptens in the development of various autoimmune-like diseases such as allergic, inflammatory, and autoimmune diseases including allergic contact dermatitis, atopy, asthma, food allergy, inflammatory bowel diseases, hemolytic anemia, liver injury, leukoderma, and even antitumor immunity. Therefore, the development of in vitro testing alternatives to evaluate in advance whether a substance might lead to the development of these diseases is highly desirable. This review summarizes and discusses recent advances in chemical- and drug-induced allergic, inflammatory, and autoimmune diseases via haptenation and the possible molecular underlying mechanisms, as well as in vitro testing alternatives to evaluate in advance whether a substance might cause the development of these diseases. [ABSTRACT FROM AUTHOR]

The current success of mRNA vaccines against COVID‐19 has highlighted the effectiveness of mRNA and DNA vaccinations. Recently, we demonstrated that a novel needle‐free pyro‐drive jet injector (PJI) effectively delivers plasmid DNA into the skin, resulting in protein expression higher than that achieved with a needle syringe. Here, we used ovalbumin (OVA) as a model antigen to investigate the potential of the PJI for vaccination against cancers. Intradermal injection of OVA‐expression plasmid DNA into mice using the PJI, but not a needle syringe, rapidly and greatly augmented OVA‐specific CD8+ T‐cell expansion in lymph node cells. Increased mRNA expression of both interferon‐γ and interleukin‐4 and an enhanced proliferative response of OVA‐specific CD8+ T cells, with fewer CD4+ T cells, were also observed. OVA‐specific in vivo killing of the target cells and OVA‐specific antibody production of both the IgG2a and IgG1 antibody subclasses were greatly augmented. Intradermal injection of OVA‐expression plasmid DNA using the PJI showed stronger prophylactic and therapeutic effects against the progression of transplantable OVA‐expressing E.G7‐OVA tumor cells. Even compared with the most frequently used adjuvants, complete Freund's adjuvant and aluminum hydroxide with OVA protein, intradermal injection of OVA‐expression plasmid DNA using the PJI showed a stronger CTL‐dependent prophylactic effect. These results suggest that the novel needle‐free PJI is a promising tool for DNA vaccination, inducing both a prophylactic and a therapeutic effect against cancers, because of prompt and strong generation of OVA‐specific CTLs and subsequently enhanced production of both the IgG2a and IgG1 antibody subclasses. [ABSTRACT FROM AUTHOR]

Background: Poly(acrylic acid) (PAA) is a water-soluble synthetic polymer with tissue-adhesive properties. When PAA is mixed with polyvinylpyrrolidone (PVP) in water, it forms a water-insoluble precipitate that neither swells nor adheres to tissues. Methods and Results: We developed a novel solid/solution interface complexation method to obtain a water-swellable PAA/PVP complex. First, PAA solution was dried up in a vessel to form a film. The PAA film was then immersed in an aqueous PVP solution to obtain a highly swollen PAA/PVP hydrogel. Heat drying of the hydrogel yielded a transparent film, while freeze-drying the hydrogel provided a soft sponge. Both the PAA/PVP film and sponge could be re-swelled by water to obtain a bioadhesive gel. A relatively larger specific surface area of the sponge than that of the film led to a more rapid swelling and water absorption behavior and quick adhesion to tissues. The addition of hyaluronic acid (HA) improved the mechanical characteristics of the sponges. PAA/PVP/HA sponges had low cytotoxicity, and they exhibited high hemostatic efficiency in clinical studies after dialysis treatment or tooth extraction, even in patients on antithrombotic drugs. Conclusions: Such bioadhesive materials consisting of low-toxicity polymers have a high potential for use in medical hemostatic devices. [ABSTRACT FROM AUTHOR]

Poly(acrylic acid) (PAA) is a water-soluble synthetic polymer that exhibits bioadhesive properties and has been applied in various novel medical devices, such as drug-delivery carriers and hemostatic agents. PAA forms a water-insoluble complex when mixed with polyvinylpyrrolidone (PVP). If PAA and PVP are mixed in water, they form an aggregated precipitate, which neither swells nor adheres to tissues. The formation of the hydrophobic complex was caused by hydrophobic interactions between the main chains of both polymers aligned the same as a zipper. To hinder the zipper-like alignment of the polymer main chains, hyaluronic acid (HA), a macromolecular viscous polysaccharide, was added to the PVP solution prior to complex formation. When the initial concentration of PAA was lower than 0.05%, HA effectively prevented the aggregation of PAA/PVP complexes and resulted in a slightly clouded suspension. Freeze-drying of the mixture yielded a soft white sponge, which could immediately swell in water to form a highly bioadhesive hydrogel. The PAA/PVP complex prepared with HA exhibited high hemostatic efficiency in clinical studies, even in patients on antithrombotic drugs. [ABSTRACT FROM AUTHOR]

To clarify the effect of collagen addition to transplanted adipose tissue on angiogenesis, cell proliferation and tissue remodelling process and reveal whether collagen addition contributes to improving transplanted adipose tissue engraftment in rats. Adipose tissue was harvested from the inguinal and injected into the back of the rat, in addition to collagen. Engraftment tissue was harvested, semi‐quantitatively evaluated and underwent haematoxylin and eosin or Perilipin staining. Moreover, we evaluated viable adipocyte counts and neovascularisation. Macrophages were evaluated using flow cytometry, and the adiponectin or vascular endothelial growth factor (VEGF) mRNA was detected using real‐time polymerase chain reaction. By collagen addition to transplanted adipose tissue, higher engraftment rate semi‐quantitatively and a greater number of new blood vessels histologically were identified. Perilipin staining revealed a higher adipocyte number. The total cell, M1 macrophage and M2 macrophage count were higher. There was increased adiponectin mRNA significantly at week 4 compared to that at week 1 after transplantation. Note that the expression levels of VEGF mRNA increased. In rats, adding collagen enhanced cell proliferation, induced M2 macrophages, which are involved in wound healing, and promoted adipocytes and neovascularisation. Therefore, collagen addition to transplanted adipose tissue could increase the engraftment rate of adipose tissue. [ABSTRACT FROM AUTHOR]

Intestinal adhesions are bands of fibrous tissue that connect the loops of the intestine to each other, to other abdominal organs or to the abdominal wall (1-3). Fibrous tissue formation is regulated by the balance between plasminogen activator inhibitor type 1 (PAI-1) and tissue-type plasminogen activator (tPA), which reciprocally regulate fibrin deposition. Several components of the inflammatory system, including cytokines (4), chemokines, cell adhesion molecules and neuropeptide substance P, have been reported to participate in adhesion formation (4-7) We have used cecal cauterization to develop a unique experimental mouse model of intestinal adhesion. Mice developed severe intestinal adhesion after this treatment. Adhesion development depended upon the interferon-[gamma] (IFN-[gamma]) and signal transducer and activator of transcription-1 (STATU system. Natural killer T (NKT) cell-deficient mice developed adhesion poorly, whereas they developed severe adhesion after reconstitution with NKT cells from wild-type mice, suggesting that NKT cell IFN-[gamma] production is indispensable for adhesion formation. This response does not depend on STAT4, STATE, interleukin-12 (IL-12), IL-18, tumor necrosis factor-[alpha], Toll-like receptor 4 or myeloid differentiation factor-88-mediated signals. Wild-type mice increased the ratio of PAI-1 to tPA after cecal cauterization, whereas [Ifng.sup.-/-] or Stat[1-/-] mice did not, suggesting that IFN-[gamma] has a crucial role in the differential regulation of PAI-1 and tPA. Additionally, hepatocyte growth factor, a potent mitogenic factor for hepatocytes (8,9), strongly inhibited intestinal adhesion by diminishing IFN-[gamma] production, providing a potential new way to prevent postoperative adhesions., Abdominal adhesion formation occurs in 67-93% of abdominal surgeries [10-13]. Adhesion also develops after abdominal bacterial infections, such as peritonitis [14]. A recent study has indicated that T helper type [...]

The interleukin-6 (IL-6)/IL-12 family of cytokines plays critical roles in the induction and regulation of innate and adaptive immune responses. Among the various cytokines, only this family has the unique characteristic of being composed of two distinct subunits, α- and β-subunits, which form a heterodimer with subunits that occur in other cytokines as well. Recently, we found a novel intracellular role for one of the α-subunits, Epstein-Barr virus-induced gene 3 (EBI3), in promoting the proper folding of target proteins and augmenting its expression at the protein level by binding to its target protein and a well-characterized lectin chaperone, calnexin, presumably through enhancing chaperone activity. Because calnexin is ubiquitously and constitutively expressed but EBI3 expression is inducible, these results could open an avenue to establish a new paradigm in which EBI3 plays an important role in further increasing the expression of target molecules at the protein level in collaboration with calnexin under inflammatory conditions. This theory well accounts for the heterodimer formation of EBI3 with p28, and probably with p35 and p19 to produce IL-27, IL-35, and IL-39, respectively. In line with this concept, another β-subunit, p40, plays a critical role in the assembly-induced proper folding of p35 and p19 to produce IL-12 and IL-23, respectively. Thus, chaperone-like activities in proper folding and maturation, which allow the secretion of biologically active heterodimeric cytokines, have recently been highlighted. This review summarizes the current understanding of chaperone-like activities of EBI3 to form heterodimers and other associations together with their possible biological implications. [ABSTRACT FROM AUTHOR]