Systemic sclerosis (SSc) is an autoimmune disease that affects skin and multiple internal organs. TGF-β, a central trigger of cutaneous fibrosis, activates fibroblasts with the involvement of the stress-inducible chaperone heat shock protein 90 isoform α (Hsp90α). Available evidence supports overexpression and secretion of Hsp90α as a feature in profibrotic pathological conditions.
View Article and Find Full Text PDFPurpose: Human mesenchymal stem cells (MSCs) have the ability to differentiate into bone-forming osteoblasts. The aim of this study was to elucidate if MSCs from patients with OP show a senescent phenotype and explore their bone-forming ability in vivo.
Materials And Methods: MSCs from patients with OP and controls with osteoarthritis (OA) were implanted into the subcutaneous tissue of immunodeficient mice for histological analysis and expression of human genes by RT-PCR.
Objective: The transforming growth factor β (TGFβ) inhibitor BAMBI (bone morphogenetic protein and activin membrane-bound inhibitor) has been shown to control differentiation of CD4+ T lymphocytes into either tolerogenic Treg cells or pathogenic Th17 cells, through the regulation of TGFβ and interleukin-2 (IL-2) signaling strength. The present study was undertaken to explore the potential beneficial effects of this strategy of pharmacologic inhibition using novel anti-BAMBI monoclonal antibodies (mAb) in different experimental murine models of chronic skin and joint inflammatory/autoimmune disease.
Methods: Development of Saccharomyces cerevisiae mannan-induced psoriatic arthritis (MIP) (n = 18-30 mice per group), imiquimod-induced skin psoriasis (n = 20-30 mice per group), or type II collagen-induced arthritis (CIA) (n = 13-16 mice per group) was analyzed in a total of 2-5 different experiments with either wild-type (WT) or BAMBI-deficient B10.
Background: CD6 is a lymphocyte surface co-receptor physically associated with the T-cell receptor (TCR)/CD3 complex at the center of the immunological synapse. There, CD6 assists in cell-to-cell contact stabilization and modulation of activation/differentiation events through interaction with CD166/ALCAM (activated leukocyte cell adhesion molecule), its main reported ligand. While accumulating evidence is attracting new interest on targeting CD6 for therapeutic purposes in autoimmune disorders, little is known on its potential in cancer.
View Article and Find Full Text PDFObjectives: To describe the clinical and epidemiologic characteristics of patients diagnosed with malaria, dengue fever, and Zika or chikungunya virus infections in a hospital emergency department. To describe the usefulness of the department's diagnostic resources.
Material And Methods: Descriptive observational study of patients diagnosed with infectious tropical diseases on the basis of samples collected in the emergency department.
Down syndrome (DS) is characterized by structural and functional anomalies that are present prenatally and that lead to intellectual disabilities. Later in life, the cognitive abilities of DS individuals progressively deteriorate due to the development of Alzheimer's disease (AD)-associated neuropathology (i.e.
View Article and Find Full Text PDFThe inhibition of apoptotic cell death in T cells through the dysregulated expression of BCL2 family members has been associated with the protection against the development of different autoimmune diseases. However, multiple mechanisms were proposed to be responsible for such protective effect. The purpose of this study was to explore the effect of the T-cell overexpression of BCL2A1, an anti-apoptotic BCL2 family member without an effect on cell cycle progression, in the development of collagen-induced arthritis.
View Article and Find Full Text PDFThe CD6 glycoprotein is a lymphocyte surface receptor putatively involved in T cell development and activation. CD6 facilitates adhesion between T cells and antigen-presenting cells through its interaction with CD166/ALCAM (activated leukocyte cell adhesion molecule), and physically associates with the T cell receptor (TCR) at the center of the immunological synapse. However, its precise role during thymocyte development and peripheral T cell immune responses remains to be defined.
View Article and Find Full Text PDFArthritis Rheumatol
June 2016
Objective: Transforming growth factor β (TGFβ) plays a prominent role in the establishment of immunologic tolerance, and mice lacking TGFβ1 die of multiorgan inflammation early in life. TGFβ controls the differentiation of CD4+ lymphocytes into Treg cells or proinflammatory Th17 cells. Although this dual capacity is modulated by the presence of additional cytokines around the activated cells, TGFβ also dissociates Th17/Treg cell differentiation in a dose-dependent manner by mechanisms still unknown.
View Article and Find Full Text PDFProteomics
October 2015
Collagen-type-II-induced arthritis (CIA) is an autoimmune disease, which involves a complex host systemic response including inflammatory and autoimmune reactions. CIA is milder in CD38(-/-) than in wild-type (WT) mice. ProteoMiner-equalized serum samples were subjected to 2D-DiGE and MS-MALDI-TOF/TOF analyses to identify proteins that changed in their relative abundances in CD38(-/-) versus WT mice either with arthritis (CIA(+) ), with no arthritis (CIA(-) ), or with inflammation (complete Freund's adjuvant (CFA)-treated mice).
View Article and Find Full Text PDFCD5 is a lymphoid-specific transmembrane glycoprotein constitutively expressed on thymocytes and mature T and B1a lymphocytes. Current data support the view that CD5 is a negative regulator of antigen-specific receptor-mediated signaling in these cells, and that this would likely be achieved through interaction with CD5 ligand/s (CD5L) of still undefined nature expressed on immune or accessory cells. To determine the functional consequence of loss of CD5/CD5L interaction in vivo, a new transgenic mouse line was generated (shCD5EμTg), expressing a circulating soluble form of human CD5 (shCD5) as a decoy to impair membrane-bound CD5 function.
View Article and Find Full Text PDFObjective: Despite the importance of Treg cells in the maintenance of immunologic tolerance, the mechanisms that control their generation and activity are unknown. Since the cell cycle inhibitor p27(Kip1) (p27) was involved in T cell anergy, we undertook this study to explore its role in both Treg cell processes.
Methods: The development of type II collagen-induced arthritis (CIA) and lupus-like abnormalities was compared between transgenic mice overexpressing human Bcl-2 in T cells (BCL2-TgT mice) and nontransgenic mice that were deficient or not deficient in p27.
CD38, a type II transmembrane glycoprotein expressed in many cells of the immune system, is involved in cell signaling, migration and differentiation. Studies in CD38 deficient mice (CD38 KO mice) indicate that this molecule controls inflammatory immune responses, although its involvement in these responses depends on the disease model analyzed. Here, we explored the role of CD38 in the control of autoimmune responses using chicken collagen type II (col II) immunized C57BL/6-CD38 KO mice as a model of collagen-induced arthritis (CIA).
View Article and Find Full Text PDFObjective: To explore the bidirectional relationship between the development of rheumatoid arthritis (RA) and atherosclerosis using bovine type II collagen (CII)-immunized B10.RIII apoE(-/-) mice, a murine model of spontaneous atherosclerosis and collagen-induced arthritis (CIA).
Methods: Male B10.
Genetic abnormalities predisposing to autoimmunity generally act in a cooperative manner affecting one or several mechanisms regulating immunological tolerance. In addition, many of these genetic abnormalities are also involved in the development of lymphoproliferative diseases. In the present study, we have determined the possible cooperation between deficiencies in members of the Cip/Kip family of cell cycle regulators (p21(WAF1/Cip1) or p27(kip1)) and the overexpression of human Bcl-2 in B lymphocytes in the induction of autoimmune and lymphoproliferative diseases in non-autoimmune C57BL/6 (B6) mice.
View Article and Find Full Text PDFObjectives: The contribution of humoral immune response in allograft and xenograft rejection has been clearly demonstrated in recent years. For this reason, inhibition of alloantibody production has become essential in managing transplanted patients. Here, we assessed the effects of the leflunomide derivative FK778 (FK778) in the control of antibody production resulting from semiallogeneic cognate T-B-cell interactions.
View Article and Find Full Text PDFThe Escherichia coli heat-labile enterotoxin (LT) possesses a powerful mucosal and systemic adjuvant effect. However, little is known about the cellular and molecular basis of the immunostimulatory activity of LT at the mucosal level, and even less information is available on the mechanisms underlying its systemic adjuvant activity. In this study, we show that distinct mechanisms are responsible for the parenteral and mucosal adjuvanticity of LT.
View Article and Find Full Text PDFEscherichia coli heat-labile enterotoxin (LT) exhibits a broad range of immunomodulatory activities, including the induction of lymphocyte-programmed cell death. In previous studies, we have demonstrated that in vivo LT promotes apoptosis of immature T and B cells through the stimulation of endogenous glucocorticoids. In the present study, we show that the extrinsic cell-death pathway as well as the apoptosis-inducing factor do not participate in the LT-induced elimination of thymocytes.
View Article and Find Full Text PDFAnimal models of autoimmune diseases, either spontaneous or induced, have been very useful tools to investigate the mechanisms involved in the pathogenesis of human autoimmune diseases as well as in the design of new therapeutic strategies for their treatment. The development of biotechnology and molecular biology resulted in the production of transgenic animals overexpressing or lacking a given protein. As a result of this technology, a great number of animal models of human diseases have been developed in recent years.
View Article and Find Full Text PDFIncreased expression of Goodpasture antigen-binding protein (GPBP), a protein that binds and phosphorylates basement membrane collagen, has been associated with immune complex-mediated pathogenesis. However, recent reports have questioned this biological function and proposed that GPBP serves as a cytosolic ceramide transporter (CERT(L)). Thus, the role of GPBP in vivo remains unknown.
View Article and Find Full Text PDFRegulation of lymphocyte survival is essential for the maintenance of lymphoid homeostasis preventing the development of autoimmune diseases. Recently, we described a systemic lupus erythematosus associated with an IgA nephropathy in autoimmune-prone (NZW x C57BL/6)F(1) overexpressing human Bcl-2 (hBcl-2) in B cells (transgenic (Tg) 1). In the present study, we analyze in detail a second line of hBcl-2 Tg mice overexpressing the transgene in all B cells and in a fraction of CD4(+) and CD8(+) T cells (Tg2).
View Article and Find Full Text PDFEscherichia coli heat-labile enterotoxin (LT) exhibits a broad range of immunomodulatory activities, including the induction of lymphocyte-programmed cell death. However, the nature of the lymphoid populations sensitive to LT-induced apoptosis and the mechanisms used by this toxin to promote such activity are still unclear. In this study, we demonstrate that LT induces in mice a rapid increase in the levels of circulating corticosterone, resulting in a dramatic induction of cell death of immature CD4+CD8+, B220+IgM- and IgM+IgD- T and B cell progenitors, respectively.
View Article and Find Full Text PDFTwo peptoids that neutralize the Gram-negative lipopolysaccharide (LPS) were identified from the screening of a positional scanning library. The evaluation of the in vivo activity of these compounds in an endoxemia murine model is also reported. These peptoids did not neutralize lipid A, i.
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