Alessandra Filardy

Federal University of Rio de Janeiro | UFRJ · IMPG

In this study, we explore the adaptive mechanisms through which the tick Rhipicephalus microplus can deal with a period of starvation, using as a model the BME26 cell line. Our findings reveal that these cells not only exhibit an impressive ability to withstand starvation but also undergo subtle structural changes in response to this nutritional re...

Efferocytosis is paramount to regulating homeostasis and inflammation. The TAM receptor family (Tyro3, Axl and MerTk) mediates efferocytosis and simultaneously inhibits pro-inflammatory pathways. Here we investigated how MerTk and Axl regulate pulmonary mucosa homeostasis and inflammation, using silicosis as a study model. During homeostasis, lung...

Adaptive immunity controls Trypanosoma cruzi infection, but the protozoan parasite persists and causes Chagas disease. T cells undergo apoptosis, and the efferocytosis of apoptotic cells might suppress macrophages and exacerbate parasite infection. Nonetheless, the receptors involved in the efferocytosis of apoptotic lymphocytes during infection re...

Despite the intramuscular route being the most used vaccination strategy against SARS-CoV-2, the intradermal route has been studied around the globe as a strong candidate for immunization against SARS-CoV-2. Adjuvants have shown to be essential vaccine components that are capable of driving robust immune responses and increasing the vaccination eff...

Mitochondria are multifunctional organelles that actively participate in the immune-inflammatory response in various pathologies. This volume updates readers on knowledge about mitochondria function. The editors have compiled six chapters about inflammation in its broadest sense, with contributions from active groups of cell biologists, infectologi...

Chagas disease (CD) is a neglected tropical disease caused by Trypanosoma cruzi infection that, despite being discovered over a century ago, remains a public health problem, mainly in developing countries. Since T. cruzi can infect a wide range of mammalian host cells, parasite–host interactions may be critical to infection outcome. The intense imm...

Efferocytosis is imperative to maintain lung homeostasis and control inflammation. Populations of lung macrophages are the main efferocytes in this tissue, responsible for controlling immune responses and avoiding unrestrained inflammation and autoimmunity through the expression of a plethora of receptors that recognize multiple 'eat me' signals on...

Fungal infections are the most common secondary infections in debilitated individuals in a state of chronic disease or immunosuppression. Despite this, most fungal infections are neglected, mainly due to the lower frequency of their more severe clinical forms in immunocompetent individuals with a healthy background. However, over the past few years...

Many aspects of giant viruses biology still eludes scientists, with viruses such as Acanthamoeba polyphaga mimivirus (APMV) and Tupanvirus (TPV) possessing large virions covered by fibrils and are cultivated in laboratories using Acanthamoeba cells as hosts. However, little is known about the infectivity of these giant viruses in vertebrate cells....

The SARS-CoV-2 pandemic has had a social and economic impact worldwide, and vaccination is an efficient strategy for diminishing those damages. New adjuvant formulations are required for the high vaccine demands, especially adjuvant formulations that induce a Th1 phenotype. Herein we assess a vaccination strategy using a combination of Alum and pol...

Leishmaniasis is a parasitic, widespread, and neglected disease that affects more than 90 countries in the world. More than 20 Leishmania species cause different forms of leishmaniasis that range in severity from cutaneous lesions to systemic infection. The diversity of leishmaniasis forms is due to the species of parasite, vector, environmental an...

The SARS-CoV-2 pandemic has had a social and economic impact worldwide, and vaccination is an efficient strategy for diminishing those damages. New adjuvant formulations are required for the high vaccine demands, especially adjuvant formulations that induce a Th1 phenotype. Herein we assess a vaccination strategy using a combination of Alum and pol...

Our findings reveal that severe COVID-19 infection is marked by hyperactive T cell responses resulting in an aging process of the immune system and acute immunodeficiency due to clonal exhaustion of CD4 T helper responses. Abstract COVID-19 can progress to severe pneumonia with respiratory failure and is aggravated by the deregulation of the immune...

Background Coronavirus disease 2019 (COVID-19) can progress to severe pneumonia with respiratory failure and is aggravated by the deregulation of the immune system causing an excessive inflammation including the cytokine storm. Methods In this study, we report that severe acutely infected patients have high levels of both type-1 and type-2 cytokin...

h3> Diabetes mellitus (DM) significantly increases the risk for cancer and cancer progression. Hyperglycemia is the defining characteristic of DM and tightly correlates with a poor prognosis in patients with cancer. The hexosamine biosynthetic pathway (HBP) is emerging as a pivotal cascade linking high glucose, tumor progression, and impaired immu...

Macrophages host Leishmania major infection, which causes cutaneous Leishmaniasis in humans. In the murine model, resistance to infection depends on the host immunity mediated by CD4 T-cell cytokines and macrophages. In association to other stimuli, the Th1 cytokine IFN-γ induces NO-mediated microbial killing by M1/classically-activated macrophages...

Com raras exceções, as supostas conexões entre morcegos, vírus e doenças em humanos estão baseadas mais em especulação do que em evidências. Por outro lado, é de chamar atenção a história de alguns surtos de doenças relacionadas a morcegos e a análise do sistema imunológico desses animais, que parecem explicar por que eles são potenciais hospedeiro...

Diabetes mellitus (DM) significantly increases the risk for cancer and cancer progression. Hyperglycemia is the defining characteristic of DM and tightly correlates with a poor prognosis in cancer patients. The hexosamine biosynthetic pathway (HBP) is emerging as a pivotal cascade linking high glucose, tumor progression and impaired immune function...

Epidemiological studies have shown diabetes mellitus (DM) to significantly increase the risk for cancer and cancer progression. Hyperglycemia is the most important characteristic of DM and directly correlates with a poor prognosis in cancer patients. While enhanced availability of glucose can directly fuel tumor cell proliferation, the effect on th...

Trypanosoma cruzi infects and replicates within a wide variety of immune and non-immune cells. Here, we investigated early cellular responses induced in NIH-3T3 fibroblasts upon infection with trypomastigote forms of T. cruzi. We show that fibroblasts were susceptible to T. cruzi infection and started to release trypomastigotes to the culture mediu...

The tumor microenvironment (TME) is composed by cellular and non-cellular components. Examples include the following: (i) bone marrow-derived inflammatory cells, (ii) fibroblasts, (iii) blood vessels, (iv) immune cells, and (v) extracellular matrix components. In most cases, this combination of components may result in an inhospitable environment,...

As key cells, able to host and kill Leishmania parasites, inflammatory monocytes/macrophages are potential vaccine and therapeutic targets to improve immune responses in Leishmaniasis. Macrophage phenotypes range from M1, which express NO-mediated microbial killing, to M2 macrophages that might help infection. Resistance to Leishmaniasis depends on...

Chagas disease is caused by infection with the protozoan Trypanosoma cruzi. CD8 T-lymphocytes help to control infection, but apoptosis of CD8 T cells disrupts immunity and efferocytosis can enhance parasite infection within macrophages. Here, we investigate how apoptosis of activated CD8 T cells affects M1 and M2 macrophage phenotypes. First, we fo...

Colonic macrophages (cMPs) are important for intestinal homeostasis as they kill microbes and yet produce regulatory cytokines. Activity of the NLRP3 (nucleotide-binding leucine-rich repeat-containing pyrin receptor 3) inflammasome, a major sensor of stress and microorganisms that results in pro-inflammatory cytokine production and cell death, must...

B-1 cells can be differentiated from B-2 cells because they are predominantly located in the peritoneal and pleural cavities and have distinct phenotypic patterns and activation properties. A mononuclear phagocyte derived from B-1 cells (B-1CDP) has been described. As the B-1CDP cells migrate to inflammatory/infectious sites and exhibit phagocytic...

Neutrophils are involved in the initial steps of most responses to pathogens and are essential components of the innate immune response. Due to the ability to produce and release various soluble mediators, neutrophils may participate in the regulation of the inflammatory response. Little is known about the role of neutrophils during protozoan infec...

We investigated early cellular responses induced by infection with Leishmania major in macrophages from resistant C57/BL6 mice. Infection increased production of reactive oxygen species by resident, but not inflammatory peritoneal macrophages. In addition, infection increased activation of stress-activated protein kinases/c-Jun N-terminal kinases (...

We investigated how apoptosis pathways mediated by death receptors and caspase-8 affect cytokine responses and immunity to Leishmania major parasites. Splenic CD4 T cells undergo activation-induced apoptosis, and blockade of FasL-Fas interaction increased IFN-γ and IL-4 cytokine responses to L. major antigens. To block death receptor-induced death,...

Purpose: To analyze the interleukin (IL)-1β and IL-10 expressions in periimplant crevicular fluid (PICF) in healthy and diseased regions to elucidate the inflammatory process around implants and its influence on clinical diagnosis. Materials and methods: PICF samples from 30 patients were analyzed for IL-1β and IL-10 concentrations by enzyme-lin...

During the last decade the majority of diphtheria cases in Europe had Corynebacterium ulcerans as the etiologic agent with dogs and cats as the reservoir hosts. However, little has been documented about the virulence factors of this zoonotic pathogen. To set up an in vivo experimental C. ulcerans infection model, conventional Swiss Webster mice wer...

Neutrophils and macrophages are phagocytic cells that cooperate during inflammation and tissue repair. Neutrophils undergo apoptosis and are engulfed by macrophages. Engulfment modulates macrophage activation and microbicidal activity. Infection by Leishmania takes place in the context of tissue repair. This article discusses cellular and molecular...

Clearance of apoptotic exudate neutrophils (efferocytosis) induces either pro- or anti-inflammatory responses in mouse macrophages depending on host genetic background. In this study, we investigated whether neutrophil efferocytosis induces a stable macrophage phenotype that could be recalled by late restimulation with LPS. Bone marrow-derived macr...

Invasive diseases caused by Corynebacterium diphtheriae have been described increasingly. Several reports indicate the destructive feature of endocarditis attributable to nontoxigenic strains. However, few reports have dealt with the pathogenicity of invasive strains. The present investigation demonstrates a phenotypic trait that may be used to ide...

The lack of information on the immunity of adults in Brazil against diphtheria prompted us to analyse sera from 234 blood donors aged 18-61 years (30.3% females and 69.7% males). IgG diphtheria antitoxin levels determined by means of an ELISA, validated by toxin neutralization test in Vero cells, showed that 30.7% (95% CI 25.0-37.1) of the populati...