Ionizable Lipid Nanoparticle-Mediated TRAIL mRNA Delivery in the Tumor Microenvironment to Inhibit Colon Cancer Progression.

Introduction: Immunotherapy has revolutionized cancer treatment by harnessing the immune system to enhance antitumor responses while minimizing off-target effects. Among the promising cancer-specific therapies, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has attracted significant attention. Methods: Here, we developed an ionizable lipid nanoparticle (LNP) platform to deliver TRAIL mRNA (LNP-TRAIL) directly to the tumor microenvironment (TME) to induce tumor cell death. Our LNP-TRAIL was formulated via microfluidic mixing and the induction of tumor cell death was assessed in vitro. Next, we investigated the ability of LNP-TRAIL to inhibit colon cancer progression in vivo in combination with a TME normalization approach using Losartan (Los) or angiotensin 1-7 (Ang(1-7)) to reduce vascular compression and deposition of extracellular matrix in mice. Results: Our results demonstrated that LNP-TRAIL induced tumor cell death in vitro and effectively inhibited colon cancer progression in vivo, particularly when combined with TME normalization induced by treatment Los or Ang(1-7). In addition, potent tumor cell death as well as enhanced apoptosis and necrosis was found in the tumor tissue of a group treated with LNP-TRAIL combined with TME normalization. Discussion: Together, our data demonstrate the potential of the LNP to deliver TRAIL mRNA to the TME and to induce tumor cell death, especially when combined with TME normalization. Therefore, these findings provide important insights for the development of novel therapeutic strategies for the immunotherapy of solid tumors.

Essential role of the CCL2-CCR2 axis in Mayaro virus-induced disease.

Mayaro virus (MAYV) is an emerging arbovirus member of the Togaviridae family and Alphavirus genus. MAYV infection causes an acute febrile illness accompanied by persistent polyarthralgia and myalgia. Understanding the mechanisms involved in arthritis caused by alphaviruses is necessary to develop specific therapies. In this work, we investigated the role of the CCL2/CCR2 axis in the pathogenesis of MAYV-induced disease. For this, wild-type (WT) C57BL/6J and CCR2-/- mice were infected with MAYV subcutaneously and evaluated for disease development. MAYV infection induced an acute inflammatory disease in WT mice. The immune response profile was characterized by an increase in the production of inflammatory mediators, such as IL-6, TNF, and CCL2. Higher levels of CCL2 at the local and systemic levels were followed by the significant recruitment of CCR2+ macrophages and a cellular response orchestrated by these cells. CCR2-/- mice showed an increase in CXCL-1 levels, followed by a replacement of the macrophage inflammatory infiltrate by neutrophils. Additionally, the absence of the CCR2 receptor protected mice from bone loss induced by MAYV. Accordingly, the silencing of CCL2 chemokine expression in vivo and the pharmacological blockade of CCR2 promoted a partial improvement in disease. Cell culture data support the mechanism underlying the bone pathology of MAYV, in which MAYV infection promotes a pro-osteoclastogenic microenvironment mediated by CCL2, IL-6, and TNF, which induces the migration and differentiation of osteoclast precursor cells. Overall, these data contribute to the understanding of the pathophysiology of MAYV infection and the identification future of specific therapeutic targets in MAYV-induced disease.IMPORTANCEThis work demonstrates the role of the CCL2/CCR2 axis in MAYV-induced disease. The infection of wild-type (WT) C57BL/6J and CCR2-/- mice was associated with high levels of CCL2, an important chemoattractant involved in the recruitment of macrophages, the main precursor of osteoclasts. In the absence of the CCR2 receptor, there is a mitigation of macrophage migration to the target organs of infection and protection of these mice against bone loss induced by MAYV infection. Much evidence has shown that host immune response factors contribute significantly to the tissue damage associated with alphavirus infections. Thus, this work highlights molecular and cellular targets involved in the pathogenesis of arthritis triggered by MAYV and identifies novel therapeutic possibilities directed to the host inflammatory response unleashed by MAYV.

Nanoparticle-based DNA vaccine protects against SARS-CoV-2 variants in female preclinical models.

A safe and effective vaccine with long-term protection against SARS-CoV-2 variants of concern (VOCs) is a global health priority. Here, we develop lipid nanoparticles (LNPs) to provide safe and effective delivery of plasmid DNA (pDNA) and show protection against VOCs in female small animal models. Using a library of LNPs encapsulating unique barcoded DNA (b-DNA), we screen for b-DNA delivery after intramuscular administration. The top-performing LNPs are further tested for their capacity of pDNA uptake in antigen-presenting cells in vitro. The lead LNP is used to encapsulate pDNA encoding the HexaPro version of SARS-CoV-2 spike (LNP-HPS) and immunogenicity and protection is tested in vivo. LNP-HPS elicit a robust protective effect against SARS-CoV-2 Gamma (P.1), correlating with reduced lethality, decreased viral load in the lungs and reduced lung damage. LNP-HPS induce potent humoral and T cell responses against P.1, and generate high levels of neutralizing antibodies against P.1 and Omicron (B.1.1.529). Our findings indicate that the protective efficacy and immunogenicity elicited by LNP-HPS are comparable to those achieved by the approved COVID-19 vaccine from Biontech/Pfizer in animal models. Together, these findings suggest that LNP-HPS hold great promise as a vaccine candidate against VOCs.

siRNA lipid nanoparticles for CXCL12 silencing modulate brain immune response during Zika infection.

CXCL12 is a key chemokine implicated in neuroinflammation, particularly during Zika virus (ZIKV) infection. Specifically, CXCL12 is upregulated in circulating cells of ZIKV infected patients. Here, we developed a lipid nanoparticle (LNP) to deliver siRNA in vivo to assess the impact of CXCL12 silencing in the context of ZIKV infection. The biodistribution of the LNP was assessed in vivo after intravenous injection using fluorescently tagged siRNA. Next, we investigated the ability of the developed LNP to silence CXCL12 in vivo and assessed the resulting effects in a murine model of ZIKV infection. The LNP encapsulating siRNA significantly inhibited CXCL12 levels in the spleen and induced microglial activation in the brain during ZIKV infection. This activation was evidenced by the enhanced expression of iNOS, TNF-α, and CD206 within microglial cells. Moreover, T cell subsets exhibited reduced secretion of IFN-É£ and IL-17 following LNP treatment. Despite no observable alteration in viral load, CXCL12 silencing led to a significant reduction in type-I interferon production compared to both ZIKV-infected and uninfected groups. Furthermore, we found grip strength deficits in the group treated with siRNA-LNP compared to the other groups. Our data suggest a correlation between the upregulated pro-inflammatory cytokines and the observed decrease in strength. Collectively, our results provide evidence that CXCL12 silencing exerts a regulatory influence on the immune response in the brain during ZIKV infection. In addition, the modulation of T-cell activation following CXCL12 silencing provides valuable insights into potential protective mechanisms against ZIKV, offering novel perspectives for combating this infection.

Delivery of Plasmid DNA by Ionizable Lipid Nanoparticles to Induce CAR Expression in T Cells.

Introduction: Chimeric antigen receptor (CAR) cell therapy represents a hallmark in cancer immunotherapy, with significant clinical results in the treatment of hematological tumors. However, current approved methods to engineer T cells to express CAR use viral vectors, which are integrative and have been associated with severe adverse effects due to constitutive expression of CAR. In this context, non-viral vectors such as ionizable lipid nanoparticles (LNPs) arise as an alternative to engineer CAR T cells with transient expression of CAR. Methods: Here, we formulated a mini-library of LNPs to deliver pDNA to T cells by varying the molar ratios of excipient lipids in each formulation. LNPs were characterized and screened in vitro using a T cell line (Jurkat). The optimized formulation was used ex vivo to engineer T cells derived from human peripheral blood mononuclear cells (PBMCs) for the expression of an anti-CD19 CAR (CAR-CD19BBz). The effectiveness of these CAR T cells was assessed in vitro against Raji (CD19+) cells. Results: LNPs formulated with different molar ratios of excipient lipids efficiently delivered pDNA to Jurkat cells with low cytotoxicity compared to conventional transfection methods, such as electroporation and lipofectamine. We show that CAR-CD19BBz expression in T cells was transient after transfection with LNPs. Jurkat cells transfected with our top-performing LNPs underwent activation when exposed to CD19+ target cells. Using our top-performing LNP-9-CAR, we were able to engineer human primary T cells to express CAR-CD19BBz, which elicited significant specific killing of CD19+ target cells in vitro. Conclusion: Collectively, our results show that LNP-mediated delivery of pDNA is a suitable method to engineer human T cells to express CAR, which holds promise for improving the production methods and broader application of this therapy in the future.

Adenosine pathway regulates inflammation during Plasmodium vivax infection.

Background: Plasmodium spp. infection triggers the production of inflammatory cytokines that are essential for parasite control, and conversely responsible for symptoms of malaria. Monocytes play a role in host defense against Plasmodium vivax infection and represent the main source of inflammatory cytokines and reactive oxygen species. The anti-inflammatory cytokine IL-10 is a key regulator preventing exacerbated inflammatory responses. Studies suggested that different clinical presentations of malaria are strongly associated with an imbalance in the production of inflammatory and anti-inflammatory cytokines. Methods: A convenience sampling of peripheral blood mononuclear cells from Plasmodium vivax-infected patients and healthy donors were tested for the characterization of cytokine and adenosine production and the expression of ectonucleotidases and purinergic receptors. Results: Here we show that despite a strong inflammatory response, monocytes also bear a modulatory role during malaria. High levels of IL-10 are produced during P. vivax infection and its production can be triggered in monocytes by P. vivax-infected reticulocytes. Monocytes express high levels of ectonucleotidases, indicating their important role in extracellular ATP modulation and consequently in adenosine production. Plasmatic levels of adenosine are not altered in patients experiencing acute malaria; however, their monocyte subsets displayed an increased expression of P1 purinergic receptors. In addition, adenosine decreases Tumor Necrosis Factor production by monocytes, which was partially abolished with the blockage of the A2a receptor. Conclusion: Monocytes have a dual role, attempting to control both the P. vivax infection and the inflammatory response. Purinergic receptor modulators emerge as an untapped approach to ameliorate clinical malaria.

Oral formulation of Wnt inhibitor complex reduces inflammation and fibrosis in intraperitoneal implants in vivo.

The use of implantable biomaterials to replace physiological and anatomical functions has been widely investigated in the clinic. However, the selection of biomaterials is crucial for long-term function, and the implantation of certain biomaterials can cause inflammatory and fibrotic processes, triggering a foreign body reaction that leads to loss of function and consequent need for removal. Specifically, the Wnt signaling pathway controls the healing process of the human body, and its dysregulation can result in inflammation and fibrosis, such as in peritoneal fibrosis. Here, we assessed the effects of daily oral administration of a Wnt pathway inhibitor complex (CD:LGK974) to reduce the inflammatory, fibrotic, and angiogenic processes caused by intraperitoneal implants. CD:LGK974 significantly reduced the infiltration of immune cells and release of inflammatory cytokines in the implant region compared to the control groups. Furthermore, CD:LGK974 inhibited collagen deposition and reduced the expression of pro-fibrotic α-SMA and TGF-ß1, confirming fibrosis reduction. Finally, the CD:LGK974 complex decreased VEGF levels and both the number and area of blood vessels formed, suggesting decreased angiogenesis. This work introduces a potential new application of the Wnt inhibitor complex to reduce peritoneal fibrosis and the rejection of implants at the intraperitoneal site, possibly allowing for longer-term functionality of existing clinical biomaterials.

Asymptomatic Plasmodium vivax malaria in the Brazilian Amazon: Submicroscopic parasitemic blood infects Nyssorhynchus darlingi.

Individuals with asymptomatic infection due to Plasmodium vivax are posited to be important reservoirs of malaria transmission in endemic regions. Here we studied a cohort of P. vivax malaria patients in a suburban area in the Brazilian Amazon. Overall 1,120 individuals were screened for P. vivax infection and 108 (9.6%) had parasitemia detected by qPCR but not by microscopy. Asymptomatic individuals had higher levels of antibodies against P. vivax and similar hematological and biochemical parameters compared to uninfected controls. Blood from asymptomatic individuals with very low parasitemia transmitted P. vivax to the main local vector, Nyssorhynchus darlingi. Lower mosquito infectivity rates were observed when blood from asymptomatic individuals was used in the membrane feeding assay. While blood from symptomatic patients infected 43.4% (199/458) of the mosquitoes, blood from asymptomatic infected 2.5% (43/1,719). However, several asymptomatic individuals maintained parasitemia for several weeks indicating their potential role as an infectious reservoir. These results suggest that asymptomatic individuals are an important source of malaria parasites and Science and Technology for Vaccines granted by Conselho Nacional de may contribute to the transmission of P. vivax in low-endemicity areas of malaria.

Plasmodium vivax Infection Alters Mitochondrial Metabolism in Human Monocytes.

Monocytes play an important role in the host defense against Plasmodium vivax as the main source of inflammatory cytokines and mitochondrial reactive oxygen species (mROS). Here, we show that monocyte metabolism is altered during human P. vivax malaria, with mitochondria playing a major function in this switch. The process involves a reprograming in which the cells increase glucose uptake and produce ATP via glycolysis instead of oxidative phosphorylation. P. vivax infection results in dysregulated mitochondrial gene expression and in altered membrane potential leading to mROS increase rather than ATP production. When monocytes were incubated with P. vivax-infected reticulocytes, mitochondria colocalized with phagolysosomes containing parasites representing an important source mROS. Importantly, the mitochondrial enzyme superoxide dismutase 2 (SOD2) is simultaneously induced in monocytes from malaria patients. Taken together, the monocyte metabolic reprograming with an increased mROS production may contribute to protective responses against P. vivax while triggering immunomodulatory mechanisms to circumvent tissue damage. IMPORTANCE Plasmodium vivax is the most widely distributed causative agent of human malaria. To achieve parasite control, the human immune system develops a substantial inflammatory response that is also responsible for the symptoms of the disease. Among the cells involved in this response, monocytes play an important role. Here, we show that monocyte metabolism is altered during malaria, with its mitochondria playing a major function in this switch. This change involves a reprograming process in which the cells increase glucose uptake and produce ATP via glycolysis instead of oxidative phosphorylation. The resulting altered mitochondrial membrane potential leads to an increase in mitochondrial reactive oxygen species rather than ATP. These data suggest that agents that change metabolism should be investigated and used with caution during malaria.

Epidemiology and Estimated Cost of Brachial Plexus Surgeries Performed through the Unified Health System in Brazil (2008­2016)

Introduction The brachial plexus is responsible for the innervation of the upper extremity of the body. About 10 to 20% of the peripheral nerve lesions are brachial plexus lesions. Objective To describe the epidemiology of the brachial plexus microsurgery with exploration and neurolysis (BPMEN) and the brachial plexus microsurgery with nerve graft (BPMNG) performed through the Brazilian Unified Health System (SUS, in the Portuguese acronym) from 2008 to 2016. Methodology A descriptive epidemiological study whose data were obtained from the Department of Informatics of the SUS (Datasus, in the Portuguese acronym). The study consisted of all patients submitted to BPMEN (code: 0403020034) and to BPMNG (code: 0403020042). Result/Discussion A total of 5,295 procedures were performed with an annual incidence of 2.94/1 million inhabitants. The hospital expenses of these 2 codes totaled R$ 4,492,603.88 (US$ 1,417,225.10). The BPMNG code presented an annual average of expenses with professional services of R$ 99,732.20 (US$ 31,461.26), and total expenses of R$ 897,589.83 (US$ 283,151.36). The amount transferred to the physician in this code in 2008 was R$ 294.56 (US$ 92.92), and currently it is R$ 441.84 (US$ 139.38). The BPMEN code presented an annual average of expenses of R$ 68,579.15 (US$ 21,633.80), with total expenses of R$ 617,212.40 (US$ 194,704.22). The amount transferred to the physician in this code in 2008 was R$ 153.44 (US$ 48.40), and currently it is R$ 230.16 (US$72.60). Both codes presented a lag in the transfer values to the physician that ranged from 16.55 to 17.64% when using the Brazilian national price index for the general consumer (IPCA, in the Portuguese acronym) as an inflation parameter during the period studied. The mean number of hospitalization days for these 2 codes was 3.79. Conclusion The absence of deaths and the low rate of hospital stay confirm that the procedure is safe, with a low morbimortality rate. Both codes presented a lag in the transfer values to the physician at the end of the period.

Segmented mechanics for traction of impacted maxillary canine: case report with a 3-year follow-up / Mecânica segmentada para tracionamento de canino su perior impactado: relato de caso com acompanhamento de 3 a nos

Young patients are increasingly concerned with smile aesthetics, resulting in the early visit to the dental office. It is of great importance that professionals such as orthodontists, pediatric dentists, and general practitioners are aware of the potential changes in positioning and development that may compromise aesthetics, considering they may prevent future complex orthodontic treatments. This case report describes the treatment of a patient aged 9 years and 4 months, who complained at assessment about the size and position of maxillary incisors. Clinically, the patient presented atresic maxilla and eruption of teeth 12 and 22. The poor positioning of tooth 22 alerted for the potential retention of tooth 23. A two-phase treatment was proposed, including an intercepting phase and a corrective phase. In the intercepting phase, rapid maxillary expansion (RME) was performed, which increased the room for eruption of tooth 23 and prevented the collapse of tooth 22. After the activation period, the Haas expander was locked and removed six months later. Twenty-five months after the removal, the second phase started with fixed corrective orthodontics and traction of tooth 23, for which the enamel was drilled and traction was performed using the segmented technique with a 0.019" x 0.025" Titanium Molybdenum Alloy (TMA) cantilever and anchorage in passive transpalatal arch (PTA). The use of this technique minimizes the side effects on the teeth adjacent to tooth 23 and enamel drilling prevents potential losses of the traction device by detachment. After 4 months of segmented mechanics, the devices were removed and the PTA was maintained. Twenty-six months later, the patient was 14 years and 4 months old, presenting direct subdivision Class III molar relationship, upper and lower crowding, and unsatisfactory relationship between bone bases due to the excessive mandibular growth. A new RME was performed, and after 3 months a Capelozza Pattern III fixed appliance was installed in the lower arch. Additionally, an upper fixed appliance was installed after the RME retention period. One year and 4 months later, the appliances were removed and a maxillary Hawley plate was installed with a 0.6-mm fixed mandibular intercanine arch. The follow-up lasted 3 years and 4 months and the results were maintained, preserving the occlusal and facial characteristics.

A preocupação dos pacientes jovens com a estética do sorriso está cada vez maior, ocasionando na visita precoce ao consultório odontológico. É de grande importância que os profissionais, tanto ortodontistas quanto odontopediatras e clínicos gerais, estejam atentos à possíveis alterações de posicionamento e desenvolvimento que comprometam a estética, visto que isso pode evitar tratamentos ortodônticos complexos no futuro. Este relato de caso descreve o tratamento de uma paciente de 9 anos e 4 meses que na avaliação se queixou do tamanho e posição dos incisivos superiores. Clinicamente apresentou maxila atrésica e dentes 12 e 22 em erupção. O mal posicionamento do dente 22 alertou para possível retenção do dente 23. Um tratamento em duas fases foi proposto: uma fase interceptadora e uma segunda fase corretiva. Na interceptadora foi realizada expansão rápida da maxila (ERM), aumentando o espaço para erupção do dente 23 e evitando colapso com o dente 22. Após o período de ativação, o expansor de Haas foi travado e sua remoção feita seis meses após o travamento. Passados 25 meses da remoção, iniciou-se a segunda fase, com ortodontia fixa corretiva e tracionamento do dente 23. Para o tracionamento, foi feita perfuração no esmalte e tracionamento por meio da técnica segmentada, utilizando cantilever de Titanium Molybdenum Alloy (TMA) 0,019" x 0,025" e ancoragem em barra transpalatina passiva (BTP). A utilização desta técnica minimiza efeitos colaterais aos dentes adjacentes ao 23 e a perfuração de esmalte evita possíveis perdas do dispositivo de tracionamento por descolagem. Após 4 meses de mecânica segmentada, removeu-se os dispositivos mantendo a BTP. Passados mais 26 meses, a paciente se encontrava com 14 anos 4 meses, relação molar de Classe III subdivisão direita, apinhamento superior e inferior e relação insatisfatória das bases ósseas, devido ao crescimento excessivo da mandíbula. Foi realizada nova ERM, após 3 meses instalou-se aparelho fixo Padrão III de Capelozza no arco inferior e, após o período de contenção da ERM, instalou-se o aparelho fixo superior. Após 1 ano e 4 meses, removeu-se os dispositivos e se instalou uma placa de Hawley superior, com barra fixa intercaninos de 0.6mm no arco inferior. Com acompanhamento de 3 anos e 4 meses, os resultados foram mantidos, preservando ascaracterísticas oclusais e faciais.

Influence of reminder therapy for controlling bacterial plaque in patients undergoing orthodontic treatment: A systematic review and meta-analysis.

OBJECTIVE: To assess the scientific evidence regarding the influence of reminder therapy on plaque index, gingival index, and white spots in patients subjected to orthodontic treatment. MATERIALS AND METHODS: Randomized clinical trials were searched in the electronic databases LILACS, PubMed, SciELO, Scopus, Web of Science, Embase, LIVIVO, and Cochrane Library. The databases OpenThesis and OpenGrey were used to capture the "gray literature," preventing selection and publication biases. The risk of bias was assessed by the Joanna Briggs Institute Critical Appraisal Checklist for Randomized Controlled Trials tool. The software Review Manager was used for the meta-analysis. The heterogeneity among studies was assessed through the I 2 statistic. A summary of the overall strength of evidence available was assessed using the Grades of Recommendations Assessment, Development, and Evaluation tool. RESULTS: A total of 332 records were found, from which only 7 articles met the inclusion criteria and were subjected to analysis. Reminder therapy showed improved scores for the plaque index (standardized mean difference = -1.22; 95% confidence interval = -2.03 to -0.42; P = .003) and the gingival index (standardized mean difference = 1.49; 95% confidence interval = -2.61 to 0.37; P = .009). Moreover, there was lower occurrence of white spots (relative risk = 0.53; 95% confidence interval = 0.38 to 0.74; P < .001) when reminder therapy was implemented. CONCLUSIONS: According to the existing high-quality evidence, reminder therapy is a valuable strategy and may contribute to the reduction of plaque and gingival indices as well as to the lower occurrence of white spots in patients subjected to orthodontic treatment.

T follicular helper cells regulate the activation of B lymphocytes and antibody production during Plasmodium vivax infection.

Although the importance of humoral immunity to malaria has been established, factors that control antibody production are poorly understood. Follicular helper T cells (Tfh cells) are pivotal for generating high-affinity, long-lived antibody responses. While it has been proposed that expansion of antigen-specific Tfh cells, interleukin (IL) 21 production and robust germinal center formation are associated with protection against malaria in mice, whether Tfh cells are found during Plasmodium vivax (P. vivax) infection and if they play a role during disease remains unknown. Our goal was to define the role of Tfh cells during P. vivax malaria. We demonstrate that P. vivax infection triggers IL-21 production and an increase in Tfh cells (PD-1+ICOS+CXCR5+CD45RO+CD4+CD3+). As expected, FACS-sorted Tfh cells, the primary source of IL-21, induced immunoglobulin production by purified naïve B cells. Furthermore, we found that P. vivax infection alters the B cell compartment and these alterations were dependent on the number of previous infections. First exposure leads to increased proportions of activated and atypical memory B cells and decreased frequencies of classical memory B cells, whereas patients that experienced multiple episodes displayed lower proportions of atypical B cells and higher frequencies of classical memory B cells. Despite the limited sample size, but consistent with the latter finding, the data suggest that patients who had more than five infections harbored more Tfh cells and produce more specific antibodies. P. vivax infection triggers IL-21 production by Tfh that impact B cell responses in humans.

Modulação da resposta imunológica por moléculas regulatórias durante a infecção pelo Plasmodium vivax / Modulation of the immune response by regulatory molecules during Plasmodium vivax infection

No Brasil a malária ainda é considerada um grande problema de saúde pública e o Plasmodium vivax é considerado o principal agente causador, com 88% de incidência. Sabe-se que a resposta contra esse parasito depende da resposta de células T e a ativação dessas envolve, além da sinalização através do receptor de célula T (TCR), a sinalização secundária, como por exemplo, a desencadeada por moléculas reguladoras. A combinação das interações mediadas por esse conjunto de moléculas regula a extensão, qualidade e duração da ativação de células T e, portanto, influencia significativamente o curso das respostas imunes. O objetivo desse trabalho é avaliar o padrão leucocitário, o perfil de expressão de receptores inibidores como morte programada-1 (PD-1), antígeno 4 associado ao linfócito T citotóxico (CTLA-4), domínios de mucina e imunoglobulina de célula T (TIM-3) e gene 3 de ativação linfocitária (LAG-3) em populações de células T, além da influencia da expressão destes receptores na modulação da produção de citocinas em pacientes infectados pelo P. vivax. Para isso, células mononucleares do sangue periférico (PBMC) foram coletadas de pacientes infectados pelo P. vivax em Porto Velho, RO e analisadas por citometria de fluxo. Os resultados demonstram que a infecção pelo P. vivax desencadeia aumento da expressão de receptores inibitórios em linfócitos T CD4+ e CD8+, principalmente em subpopulações de memória e em células de T reguladoras (Treg)

Importante mencionar que ensaios funcionais, utilizando-se anticorpos monoclonais específicos para CTLA-4, PD-1, TIM-3, confirmaram a função moduladora dessesreceptores levando ao aumento da produção de citocinas por células antígeno-específicas. As células Treg também apresentam capacidade prejudicada durante a malária. Apesar da expressão aumentada de PD-1, não foi estabelecido uma relação direta entre a expressão deste e da perda da modulação pelas Treg. No entanto, a expressão aumentada de PD-1 é coincidente com a diminuição da expressão de Foxp3 e Helios, e com o aumento de Tbet, e consequentemente com o aumento da produção de IFN-γ. Nossos dados corroboram nossa hipótese de que o aumento da expressão de receptores inibitórios durante a infecção pelo P. vivax prejudica funções efetoras de células T. Novas abordagens precisam ser exploradas para confirmarmos se a expressão de PD-1 por Treg é apenas um biomarcador de perda de função, ou se essa molécula influencia diretamente a função efetora dessa célula durante a malária vivax

Dengue Patients with Early Hemorrhagic Manifestations Lose Coordinate Expression of the Anti-Inflammatory Cytokine IL-10 with the Inflammatory Cytokines IL-6 and IL-8.

Dengue is responsible for a wide range of clinical manifestations, ranging from asymptomatic infections to severe cases. The alteration of cytokine levels correlated with clinical characteristics can help determine prognostic markers of the disease and the identification of targets for immunotherapy. We measured the viral load, serotype, and cytokine levels of 212 serum samples from patients with acute dengue infection during days 1-4 after the onset of symptoms. The patients were classified as either with hemorrhagic manifestations (HM) or with no hemorrhagic manifestations (NHM). The cytokines interleukin-6 (IL-6), IL-8, and IL-10 were increased (P < 0.05) in the dengue virus+ group, compared with the control group. A higher viral load (P < 0.05) and IL-6 was detected in the HM group compared with the NHM group. Interestingly, the NHM group demonstrated a significant positive correlation between inflammatory (IL-6 and 8) and anti-inflammatory (IL-10) cytokines, whereas the HM group did not. These findings suggest that a disturbance in the balance of inflammatory cytokines IL-6 and IL-8 with the anti-inflammatory cytokine, IL-10, combined with the high levels of IL-6 and viral load, characterize possible mechanisms related to the formation of HM.

Fibrina rica em plaquetas e a reconstrução tecidual periodontal / Platelet-rich fibrin and periodontal tissue regeneration ­ a literature review

As evidências na literatura dos efeitos benéficos dos concentrados de plaqueta, obtidos do sangue autólogo em procedimentos cirúrgicos periodontais, têm aumentado muito nos últimos anos. O uso da fibrina rica em plaquetas ainda se encontra na fase inicial, porém, o potencial clínico de suas aplicações é muito promissor. O objetivo desta revisão foi conceituar o uso da fibrina rica em plaquetas como um procedimento que visa à regeneração das estruturas periodontais perdidas. Pôde-se concluir que a fibrina rica em plaquetas tem grande potencial de aplicação nas cirurgias periodontais e peri-implantares, demonstrando ser eficaz no tratamento de defeitos infraósseos de três paredes e de furca II mandibulares, sendo um procedimento de baixa complexidade e morbidade, de fácil aplicação clínica e com baixo custo.

The evidence in the literature of the beneficial effects of platelet concentrates obtained from autologous blood in periodontal surgical procedures has increased significantly in recent years. The use of platelet-rich fibrin is still in its early days; however, their clinical application is very promising. The objective of this review was to conceptualize the use of platelet-rich fibrin as a procedure which aims to the regeneration of lost periodontal structures. It could be concluded that platelet-rich fibrin have great potential for application in periodontal and peri-implant surgeries and have shown to be effective in treating intra-bony 3 walls and mandibular furcation II defects, being a low complexity and morbidity procedure, easy for clinical applicability and of a low cost.

The robust and modulated biomarker network elicited by the Plasmodium vivax infection is mainly mediated by the IL-6/IL-10 axis and is associated with the parasite load.

BACKGROUND: Recent studies have shown that the inflammatory process, including the biomarker production, and the intense activation of innate immune responses are greater in the malaria caused by Plasmodium vivax than other species. Here, we examined the levels of serum biomarkers and their interaction during acute malaria. MATERIAL AND METHODS: Blood samples were collected from P. vivax-infected patients at admission and from healthy donors. Levels of serum biomarkers were measured by Cytometric Bead Assay or ELISA. RESULTS: P. vivax infection triggered the production of both inflammatory and regulatory biomarkers. Levels of IL-6, CXCL-8, IFN-γ, IL-5, and IL-10 were higher in P. vivax-infected patients than in healthy donors. On the other hand, malaria patients produced lower levels of TNF-α, IL-12p70, and IL-2 than healthy individuals. While the levels of IL-10 and IL-6 were found independent on the number of malaria episodes, higher levels of these cytokines were seen in patients with higher parasite load. CONCLUSION: A mixed pattern of proinflammatory and regulatory biomarkers is produced in P. vivax malaria. Analysis of biomarker network suggests that IL-10 and IL-6 are a robust axis in malaria patients and that this interaction seems to be associated with the parasite load.

Caracterização de moléculas reguladoras durante a malária vivax

No Brasil a malária ainda é considerada um grande problema de saúde pública.Embora o número de casos de malária esteja diminuindo, a incidência foi maior que 300.000 casos nos últimos dois anos. Destes casos, o Plasmodium vivax foi considerado o principal agente causador, com 90% de incidência. A resposta imune adaptativa, com oauxílio da imunidade inata, tem a função de superar as estratégias impostas pelos agentes infecciosos, levando ao controle da infecção. A ativação de células T envolve além da sinalização através do receptor de célula T (TCR), sinalização secundária desencadeadapor moléculas reguladoras. A combinação das interações mediadas por estes regula a extensão, qualidade e duração da ativação de células T e, portanto, influenciam significativamente no curso das respostas imunes em questão. O objetivo desse trabalhoé avaliar o fenótipo de células T de pacientes infectados pelo P. vivax com o foco na expressão de moléculas reguladoras como morte programada-1 (PD-1), co-estimulador induzível de células T (ICOS), antígeno 4 associado ao linfócito T citotóxico (CTLA-4), domínios de mucina e imunoglobulina de célula T (TIM-3) e gene 3 de ativaçãolinfocitária (LAG-3). Células mononucleares do sangue periférico foram coletadas de pacientes infectados pelo P. vivax em Porto Velho, RO.

Os linfócitos foram analisados por citometria de fluxo. Os resultados demonstram um aumento de citocinas inflamatórias e uma diminuição no número de linfócitos em pacientes infectados pelo P. vivax. Na literatura, a expressão desses receptores inibidores e moléculas coestimulatórias é associada com a diminuição de função de células T. Nossos resultados demonstram um aumento da expressão das moléculas citadas acima em pacientes infectados pelo P. vivax. O aumento da expressão de algumas dessas moléculas correlacionam com o dano hepático e com plaquetopenia em pacientes infectados pelo P. vivax. Além disso, foi observado um aumento da expressão de um marcador específico da proliferação celular, o Ki67, em pacientes infectados pelo P. vivax. Acaracterização fenotípica aqui realizada sugere disfuncionalidade das células T. Estudos adicionais devem ser realizados para avaliar a função destas moléculas durante a malária

Caracterização de moléculas reguladoras durante a malária vivax / Characterization of molecules regulatory during the malaria vivax

No Brasil a malária ainda é considerada um grande problema de saúde pública.Embora o número de casos de malária esteja diminuindo, a incidência foi maior que 300.000 casos nos últimos dois anos. Destes casos, o Plasmodium vivax foi considerado o principal agente causador, com 90% de incidência. A resposta imune adaptativa, com oauxílio da imunidade inata, tem a função de superar as estratégias impostas pelos agentes infecciosos, levando ao controle da infecção. A ativação de células T envolve além da sinalização através do receptor de célula T (TCR), sinalização secundária desencadeadapor moléculas reguladoras. A combinação das interações mediadas por estes regula a extensão, qualidade e duração da ativação de células T e, portanto, influenciam significativamente no curso das respostas imunes em questão. O objetivo desse trabalhoé avaliar o fenótipo de células T de pacientes infectados pelo P. vivax com o foco na expressão de moléculas reguladoras como morte programada-1 (PD-1), co-estimulador induzível de células T (ICOS), antígeno 4 associado ao linfócito T citotóxico (CTLA-4), domínios de mucina e imunoglobulina de célula T (TIM-3) e gene 3 de ativaçãolinfocitária (LAG-3). Células mononucleares do sangue periférico foram coletadas de pacientes infectados pelo P. vivax em Porto Velho, RO. Os linfócitos foram analisados por citometria de fluxo. Os resultados demonstram um aumento de citocinas inflamatórias e uma diminuição no número de linfócitos em pacientes infectados pelo P. vivax. Na literatura, a expressão desses receptores inibidores e moléculas coestimulatórias é associada com a diminuição de função de células T. Nossos resultados demonstram um aumento da expressão das moléculas citadas acima em pacientes infectados pelo P. vivax. O aumento da expressão de algumas dessas moléculas correlacionam com o dano hepático e com plaquetopenia em pacientes infectados pelo P. vivax. Além disso, foi observado um aumento da expressão de um marcador específico da proliferação celular, o Ki67, em pacientes infectados pelo P. vivax. Acaracterização fenotípica aqui realizada sugere disfuncionalidade das células T. Estudos adicionais devem ser realizados para avaliar a função destas moléculas durante a malária.