Background: CD72 is a highly required regulatory molecule in B cells. Its sufficient expression is crucial for maintaining self-tolerance. In contrast, soluble CD72 (sCD72) is reported to be increased in the serum of autoimmune diseases such as systemic lupus erythematosus and primary Sjogren's syndrome (pSS).
View Article and Find Full Text PDFThe Lymphocyte-Activation Protein 3 (LAG-3) inhibitory receptor is expressed on regulatory plasma cells (PCs). Micro-environmental cells that express LAG-3 were found to be increased during the progression of smoldering multiple myeloma (SMM). To assess the possible role of LAG-3 expression on regulatory PCs in patients with plasma cell dyscrasia.
View Article and Find Full Text PDFRegulatory molecules have recently been recognized for their beneficial effects in the treatment of immune-mediated diseases, rather than using cytotoxic immune-suppressing drugs, which are associated with many unwanted side effects. Semaphorin3A (sema3A), a unique regulatory master of the immune system, was shown to be decreased in the serum of systemic lupus erythematosus (SLE) patients, in association with disease severity. Later, we were able to show its extremely beneficial effect in treating lupus nephritis in the NZB/W mice model.
View Article and Find Full Text PDFThe semaphorin guidance factors receptor plexin-A2 transduces sema6A and sema6B signals and may mediate, along with plexin-A4, the anti-angiogenic effects of sema6A. When associated with neuropilins plexin-A2 also transduces the anti-angiogenic signals of sema3B. Here we show that inhibition of plexin-A2 expression in glioblastoma derived cells that express wild type p53 such as U87MG and A172 cells, or in primary human endothelial cells, strongly inhibits cell proliferation.
View Article and Find Full Text PDFBackground: Glycogen storage disease type 1b (GSD1b) is an ultra-rare autosomal recessive disorder, caused by mutations in gene. Affected patients present with episodes of fasting hypoglycemia and lactic acidosis, hepatomegaly, growth retardation, hyperlipidemia and renal impairment. In addition, patients present neutropenia, neutrophil dysfunction and oral, and skin infections as well as a significant predisposition to develop inflammatory bowel disease (IBD).
View Article and Find Full Text PDFCD72 is a regulatory co-receptor on B cells, with a role in the pathogenesis of systemic lupus erythematosus (SLE) in both human and animal models. Semaphorin3A (sema3A) is a secreted member of the semaphorin family that can reconstruct B cells' regulatory functions by upregulating IL-10 expression and inhibiting the pro-inflammatory activity of B and T cells in autoimmune diseases. The aim of our present study was to identify a new ligand for CD72, namely sema3A, and exploring the signal transduction pathways following its ligation in B cells.
View Article and Find Full Text PDFImmune semaphorins are important in controlling both innate and adaptive immune responses. The regulatory role of semaphorin3A (sema3A) in systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and other autoimmune diseases is widely reported. Decreased levels of serum sema3A were shown to correlate with SLE disease activity.
View Article and Find Full Text PDFPatients with chronic spontaneous urticaria (CSU), an autoimmune disorder, show increased skin expression of IL-17A and can benefit from treatment with the anti-IL-17A biologic secukinumab. The mechanisms that drive IL-17A expression in CSU are currently unknown, but may involve Semaphorin5A (Sema5A). To explore the expression, role, and effects of Sema5A in CSU and its link to IL-17A.
View Article and Find Full Text PDFSemaphorin 3A (sema3A) belongs to the sub-family of the immune semaphorins that function as regulators of immune-mediated inflammation. Sema3A is a membrane associated molecule on T regulatory cells and on B regulatory cells. Being transiently ligated to the cell surface of these cells it is suggested to be a useful marker for evaluating their functional status.
View Article and Find Full Text PDFBackground: The immune regulatory properties of semaphorin3A (sema3A) (both innate and adaptive) are well established in many studies. The injection of sema3A into a mice model of rheumatoid arthritis was proven to be highly beneficial, both in attenuating clinical symptoms and in decreasing inflammatory mechanisms.
Objectives: This study was designed in order to assess the possible therapeutic benefits of sema3A following its injection into female NZB/W mice.
Class 3 semaphorins are anti-angiogenic and anti-tumorigenic guidance factors that bind to neuropilins, which, in turn, associate with class A plexins to transduce semaphorin signals. To study the role of the plexin-A2 receptor in semaphorin signaling, we silenced its expression in endothelial cells and in glioblastoma cells. The silencing did not affect Sema3A signaling, which depended on neuropilin-1, plexin-A1 and plexin-A4, but completely abolished Sema3B signaling, which also required plexin-A4 and one of the two neuropilins.
View Article and Find Full Text PDFClass-3 semaphorins are secreted axon guidance factors. Some of these semaphorins have recently been characterized as suppressors of tumor progression. To determine if class-3 semaphorins can be used to inhibit the development of glioblastoma-multiforme tumors, we expressed recombinant sema-3A, 3B, 3D, 3E, 3F or 3G in U87MG glioblastoma cells.
View Article and Find Full Text PDFThe semaphorins were initially described as axon guidance factors, but have recently been implicated in a variety of physiological and developmental functions, including regulation of immune response, angiogenesis, and migration of neural crest cells. The semaphorin family contains more than 30 genes divided into seven subfamilies, all of which are characterized by the presence of a sema domain. The semaphorins transduce their signals by binding to one of the nine receptors belonging to the plexin family, or, in the case of the class 3 semaphorins, by binding to one of the two neuropilin receptors.
View Article and Find Full Text PDFGap junctions form intercellular channels that mediate metabolic and electrical signaling between neighboring cells in a tissue. Lack of an atomic resolution structure of the gap junction has made it difficult to identify interactions that stabilize its transmembrane domain. Using a recently computed model of this domain, which specifies the locations of each amino acid, we postulated the existence of several interactions and tested them experimentally.
View Article and Find Full Text PDFConnexins are a family of transmembrane proteins that form gap junctions between adjacent cells and allow intercellular communication. Connexin proteins are involved in pathological conditions in humans, mainly in hearing loss, neurodegenerative disorders and skin diseases. The association between connexin proteins and the inner ear is well established.
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