Publications by authors named "Claudia da Silva Bitencourt"

Microencapsulation of bioactive molecules for modulating the immune response during infectious or inflammatory events is a promising approach, since microspheres (MS) protect these labile biomolecules against fast degradation, prolong the delivery over longer periods of time and, in many situations, target their delivery to site of action, avoiding toxic side effects. Little is known, however, about the influence of different polymers used to prepare MS on macrophages. This paper aims to address this issue by evaluating in vitro cytotoxicity, phagocytosis profile and cytokines release from alveolar macrophages (J-774.

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Biodegradable lactic-co-glycolic acid (PLGA) microspheres (MS) improve the stability of biomolecules stability and allow enable their sustained release. Lipid mediators represent a strategy for improving host defense; however, most of these mediators, such as prostaglandin D2 (PGD2), have low water solubility and are unstable. The present study aimed to develop and characterize MS loaded with PGD2 (PGD2-MS) to obtain an innovative tool to activate macrophages.

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Tityus serrulatus venom (TsV) consists of numerous peptides with different physiological and pharmacological activities. Studies have shown that scorpion venom increases pro-inflammatory cytokine production, contributing to immunological imbalance, multiple organ dysfunction, and patient death. We have previously demonstrated that TsV is a venom-associated molecular pattern (VAMP) recognized by TLRs inducing intense inflammatory reaction through the production of pro-inflammatory cytokines and arachidonic acid-derived lipid mediators prostaglandin (PG)E2 and leukotriene (LT)B4.

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The aim of this work was to develop an innovative tool for the treatment of pulmonary fibrosis based on our previous findings, which demonstrated that intranasally administered soluble bovine hyaluronidase (HYAL) increases the numbers of mesenchymal (MSC)-like cells in the bronchoalveolar fluid (BALF) and thus reduces the bleomycin-induced fibrosis. To this end, we developed poly(D,L-lactide-co-glycolide) (PLGA) microparticles (MPs) loaded with HYAL (HYAL-MP) to preserve the enzyme's biological activity and to facilitate its delivery to the lung. Nonloaded MPs (Control-MPs) and HYAL-MPs were prepared using the emulsion and solvent evaporation methods and thoroughly characterized.

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Scorpion sting-induced human envenomation provokes an intense inflammatory reaction. However, the mechanisms behind the recognition of scorpion venom and the induction of mediator release in mammalian cells are unknown. We demonstrated that TLR2, TLR4 and CD14 receptors sense Tityus serrulatus venom (TsV) and its major component, toxin 1 (Ts1), to mediate cytokine and lipid mediator production.

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Prostaglandins act as mediators of inflammation and, similar to cytokines, function as immune modulators during innate and adaptive immune responses. Therefore, using a pharmacological inhibitor, celecoxib, we investigated the role of prostaglandins in host defense against Histoplasma capsulatum infection in C57BL/6 mice. Our results showed that treatment with celecoxib inhibited cyclooxygenase 2, reduced the total fungal burden, and reduced the concentration of PGE2, cytokines, lymphocytes, neutrophils, and mononuclear cells in the bronchoalveolar space and lung parenchyma.

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Inflammatory mediators are thought to be involved in the systemic and local immune response induced by the Tityus serrulatus scorpion envenomation. New functional aspects of lipid mediators have recently been described. Here, we examine the unreported role of lipid mediators in cell recruitment to the peritoneal cavity after an injection with Ts2 or Ts6 toxins isolated from the T.

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Scorpion envenomation induces a systemic immune response, and neurotoxins of venom act on specific ion channels, modulating neurotransmitter release or activity. However, little is known about the immunomodulatory effects of crude venom from scorpion Tityus serrulatus (TsV) or its toxins (Ts1, Ts2 and Ts6) in combination with lipopolysaccharide (LPS). To investigate the immunomodulatory effects of TsV and its toxins (Ts1, Ts2 and Ts6), J774.

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