26 research outputs found
A crucial role for HVEM and BTLA in preventing intestinal inflammation
The interaction between the tumor necrosis factor (TNF) family member LIGHT and the TNF family receptor herpes virus entry mediator (HVEM) co-stimulates T cells and promotes inflammation. However, HVEM also triggers inhibitory signals by acting as a ligand that binds to B and T lymphocyte attenuator (BTLA), an immunoglobulin super family member. The contribution of HVEM interacting with these two binding partners in inflammatory processes remains unknown. In this study, we investigated the role of HVEM in the development of colitis induced by the transfer of CD4(+)CD45RB(high) T cells into recombination activating gene (Rag)(-/-) mice. Although the absence of HVEM on the donor T cells led to a slight decrease in pathogenesis, surprisingly, the absence of HVEM in the Rag(-/-) recipients led to the opposite effect, a dramatic acceleration of intestinal inflammation. Furthermore, the critical role of HVEM in preventing colitis acceleration mainly involved HVEM expression by radioresistant cells in the Rag(-/-) recipients interacting with BTLA. Our experiments emphasize the antiinflammatory role of HVEM and the importance of HVEM expression by innate immune cells in preventing runaway inflammation in the intestine
Features of business modeling in innovative industries
he main publications related to business modeling appeared at the turn of the century. They focused on establishing connections between ways of doing business and sources of income. The expansion of such sources, caused, in particular, by the emergence of new information technologies, required a revision of approaches to all business processes – primary and auxiliary. In addition to the modification of traditional industries, new ones based on innovative technologies began to develop actively. Business modeling allowed startup founders to look at a nascent business as a whole, taking into account and coordinating its main elements. Now, many innovative companies, on the example of which business modeling was formed, have become global giants. As a rule, the development of such companies is associated with the fourth technological revolution and is based on information and communication technologies (ICT). However, for some industries, ICT is a supporting element of activity, and the production itself requires the involvement and processing of a large number of material resources, as, for example, for pharmaceuticals. As a result, information and traditional technologies are a complex symbiosis that affects all aspects of doing business. The combination of production and information technologies in various industries forms a variety of successful business models. Nevertheless, their industry differences have not yet been comparatively analyzed. The purpose of the study is to identify both general trends in the transformation of business model elements in innovative companies and their differences. To answer the question about the nature of business models of innovative companies, the article provides reviews the main concepts of such models. Because this approach has gone through several stages and currently there are more than a hundred variants of what the authors call “business model” in the literature, the article proposes approaches to their classification according to such features as the product offered to the market and the monetization model. Based on the classification, the article analyzes the formation and transformation of business models, taking into account the realities of new markets, the specifics of interaction with suppliers, customers, institutional agents, etc. The article is based on the analysis of scientific publications and a statistical review. The analysis is based on the experience of both leading foreign companies and domestic innovative enterprises in such areas as ICT, biotechnology, logistics. It is concluded that some trends are similar, such as expansion of cooperation and the inclusion of new entities from non-core industries in the value chain. It is noted that some industries are still looking for scalable models that would allow all market participants to move to stable business management
NIK-dependent RelB Activation Defines a Unique Signaling Pathway for the Development of Vα14i NKT Cells
A defect in RelB, a member of the Rel/nuclear factor (NF)-κB family of transcription factors, affects antigen presenting cells and the formation of lymphoid organs, but its role in T lymphocyte differentiation is not well characterized. Here, we show that RelB deficiency in mice leads to a selective decrease of NKT cells. RelB must be expressed in an irradiation-resistant host cell that can be CD1d negative, indicating that the RelB expressing cell does not contribute directly to the positive selection of CD1d-dependent NKT cells. Like RelB-deficient mice, aly/aly mice with a mutation for the NF-κB–inducing kinase (NIK), have reduced NKT cell numbers. An analysis of NK1.1 and CD44 expression on NKT cells in the thymus of aly/aly mice reveals a late block in development. In vitro, we show that NIK is necessary for RelB activation upon triggering of surface receptors. This link between NIK and RelB was further demonstrated in vivo by analyzing RelB+/− × aly/+ compound heterozygous mice. After stimulation with α-GalCer, an antigen recognized by NKT cells, these compound heterozygotes had reduced responses compared with either RelB+/− or aly/+ mice. These data illustrate the complex interplay between hemopoietic and nonhemopoietic cell types for the development of NKT cells, and they demonstrate the unique requirement of NKT cells for a signaling pathway mediated by NIK activation of RelB in a thymic stromal cell
Villous B Cells of the Small Intestine Are Specialized for Invariant NK T Cell Dependence
B cells are important in mucosal microbial homeostasis through their well-known role in secretory IgA production and their emerging role in mucosal immunoregulation. Several specialized intraintestinal B cell compartments have been characterized, but the nature of conventional B cells in the lamina propria is poorly understood. In this study, we identify a B cell population predominantly composed of surface IgM+IgD+cells residing in villi of the small intestine and superficial lamina propria of the large intestine, but distinct from the intraepithelial compartment or organized intestinal lymphoid structures. Small intestinal (villous) B cells are diminished in genotypes that alter the strength of BCR signaling (Bruton tyrosine kinasexid, Gαi2−/−), and in mice lacking cognate BCR specificity. They are not dependent on enteric microbial sensing, because they are abundant in mice that are germfree or genetically deficient in TLR signaling. However, villous B cells are reduced in the absence of invariant NK T cells (Jα18−/− or CD1d−/− mice). These findings define a distinct population of conventional B cells in small intestinal villi, and suggest an immunologic link between CD1-restricted invariant NK T cells and this B cell population
RAGE, carboxylated glycans and S100A8/A9 play essential roles in colitis-associated carcinogenesis
Patients with inflammatory bowel diseases are at increased risk for colorectal cancer, but the molecular mechanisms linking inflammation and cancer are not well defined. We earlier showed that carboxylated N-glycans expressed on receptor for advanced glycation end products (RAGE) and other glycoproteins mediate colitis through activation of nuclear factor kappa B (NF-κB). Because NF-κB signaling plays a critical role in the molecular pathogenesis of colitis-associated cancer (CAC), we reasoned that carboxylated glycans, RAGE and its ligands might promote CAC. Carboxylated glycans are expressed on a subpopulation of RAGE on colon cancer cells and mediate S100A8/A9 binding to RAGE. Colon tumor cells express binding sites for S100A8/A9 and binding leads to activation of NF-κB and tumor cell proliferation. Binding, downstream signaling and tumor cell proliferation are blocked by mAbGB3.1, an anti-carboxylate glycan antibody, and by anti-RAGE. In human colon tumor tissues and in a mouse model of CAC, we found that myeloid progenitors expressing S100A8 and S100A9 infiltrate regions of dysplasia and adenoma. mAbGB3.1 administration markedly reduces chronic inflammation and tumorigenesis in the mouse model of CAC and RAGE-deficient mice are resistant to the onset of CAC. These findings show that RAGE, carboxylated glycans and S100A8/A9 play essential roles in tumor–stromal interactions, leading to inflammation-associated colon carcinogenesis