Molecular immunology
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Molecular immunology · Nov 2015
ReviewParallel activities and interactions between antimicrobial peptides and complement in host defense at the airway epithelial surface.
Antimicrobial peptides and complement components contribute to host defense as well as inflammation and tissue injury in the respiratory tract. The airway epithelial surface is the main site of action of these immune effectors, and airway epithelial cells contribute markedly to their local production. ⋯ Therefore, further knowledge of interactions between these systems may provide more insight into the pathogenesis of a range of lung diseases. In this review, recent findings on the functions, collaborations and other interactions between antimicrobial peptides and complement are discussed with a specific focus on the airway epithelium.
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Molecular immunology · Sep 2015
ReviewParoxysmal nocturnal hemoglobinuria (PNH) and primary p.Cys89Tyr mutation in CD59: Differences and similarities.
CD59 encodes a 77 amino acid glycosylphosphatidylinositol (GPI)-anchored cell surface glycoprotein that inhibits the final step of membrane attack complex (MAC) formation. CD59 deficiency is a common finding in adult patients with paroxysmal nocturnal hemoglobinuria (PNH). In this condition, there is a clonal expansion of hematopoietic stem cells that have acquired a mutation in the PIGA gene (phosphatidylinositol glycan anchor biosynthesis, class A). ⋯ Cys89Tyr with resulting failure of proper localization of the CD59 protein to the cell surface. The Cys89Tyr mutation in CD59 was clinically manifested in infancy, and associated with chronic hemolysis and relapsing peripheral demyelinating disease resembling recurrent Guillain-Barré syndrome (GBS) or chronic inflammatory demyelinating polyneuropathy (CIDP). In this review we describe differences and similarities in the pathogenesis and clinical manifestations of PNH and primary CD59 Cys89Tyr mutation with the aim of tracking the contribution of CD59 deficiency to the pathophysiology and perhaps deepening our understanding of both diseases.
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Molecular immunology · Aug 2015
Mechanisms that lead to the regulation of NLRP3 inflammasome expression and activation in human dental pulp fibroblasts.
The NLRP3 inflammasome plays an important role in the cellular defense against invading pathogens and is reported to be expressed in human dental pulp fibroblasts (HDPFs). However, the role of the NLRP3 inflammasome in HDPFs during pulpal infection and inflammation remains unclear. ⋯ Our results demonstrated that the NLRP3 inflammasome in HDPFs is crucial for IL-1β secretion in response to LPS plus ATP. LPS engaged the TLR4/MyD88/NF-κB pathway to enhance NLRP3 and pro-IL-1β expression in HDPFs. ATP promoted the generation of ROS and activated the NLRP3 inflammasome in a ROS-dependent manner.
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Molecular immunology · Aug 2015
Soluble monosodium urate, but not its crystal, induces toll like receptor 4-dependent immune activation in renal mesangial cells.
Uric acid has emerged as a novel and potential modifiable risk factor for the incidence and progression of kidney diseases, however, the deteriorate effect of uric acid on renal mesangial cells remains unclear. The present study is to examine the immune activation of soluble and crystal forms of uric acid in human mesangial cells. ⋯ Our results suggested that soluble MSU, but not MSU crystals, induce NLRP3, IL-1β, HLA-DR and CD40 upregulation in a TLR4-dependent manner. These findings indicate that soluble MSU may play a pathological role in hyperuricemia induced renal mesangial injury.
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Molecular immunology · Aug 2015
Enhanced and durable protective immune responses induced by a cocktail of recombinant BCG strains expressing antigens of multistage of Mycobacterium tuberculosis.
Although Bacillus Calmette-Guérin (BCG) vaccine confers protection from Mycobacterium tuberculosis infection in children, its immune protection gradually wanes over time, and consequently leads to an inability to prevent the reactivation of latent infection of M. tuberculosis. Therefore, improving BCG for better control of tuberculosis (TB) is urgently needed. We thus hypothesized that recombinant BCG overexpressing immunodominant antigens expressed at different growth stages of M. tuberculosis could provide a more comprehensive protection against primary and latent M. tuberculosis infection. ⋯ Our results showed that ABX was able to induce a stronger immune protection than individual rBCGs or BCG against primary TB infection in C57BL/6 mice. Mechanistically, the immune protection was attributed to stronger antigen-specific CD4(+) Th1 responses, higher numbers of IFN-γ(+) CD4(+) TEM and IL-2(+) CD8(+) TCM cells elicited by ABX. These findings thus provide a novel strategy for the improvement of BCG efficacy and potentially a promising prophylactic TB vaccine candidate, warranting further investigation.