Nico D, Conde L, Rivera-Correa JL, Vasconcelos-Dos-Santos A, Mesentier-Louro L, Freire-de-Lima L, Arruda MB, Freire-de-Lima CG, Ferreira ODC Jr, Lopes Moreira ME, Zin AA, Vasconcelos ZFM, Otero RM, Palatnik-de-Sousa CB, Tanuri A, Todeschini AR, Savino W, Rodriguez A, Morrot A. Prevalence of IgG Autoantibodies against GD3 Ganglioside in Acute Zika Virus Infection. Front Med (Lausanne). 2018 Mar 9;5:25.

DOI: 10.3389/fmed.2018.00025

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Zika virus (ZIKV) disease has become a global health emergency with devastating effects on public health. Recent evidences implicate the virus as an emergent neuropathological agent promoting serious pathologies of the human nervous system, that include destructive and malformation consequences such as development of ocular and fetal brain lesions, microcephaly in neonates, and Guillain–Barré syndrome (GBS) in adults. These neurological disorders of both central and peripheral nervous systems are thought to be associated to the neurotropic properties of the virus that has ability to infect neural stem cells as well as peripheral neurons, a hallmark of its pathogenicity. The presence of autoantibodies against gangliosides plays a pivotal role in the etiogenesis of GBS and a variety of neurological disorders. Gangliosides are a class of galactose-containing cerebrosides mainly expressed in nervous system tissues playing a critical role in the physiology of neural cells and neurogenesis. Herein, our findings indicate that patients at acute phase of ZIKV infection without any neurological signs show increased levels of IgG autoantibody against GD3 gangliosides, a class of glycolipid found to be highly expressed in neural stem cell acting in the maintenance of their self-renewal cellular capacity. It is possible that a pathological threshold of these antibodies is only acquired in secondary or subsequent infections. In the light of these evidences, we propose that the target of GD3 by autoimmune responses may possibly has an effect in the neuropathy and neurogenesis disorder seen during ZIKV infection.

Nunes CF, Nogueira JS, Vianna PHO, Ciambarella BT, Rodrigues PM, Miranda KR, Lobo LA, Domingues RMCP, Busch M, Atella GC, Vale AM, Bellio M, Nóbrega A, Canto FB, Fucs R. Probiotic treatment during neonatal age provides optimal protection against experimental asthma through the modulation of microbiota and T cells. Int Immunol. 2018 Apr 3;30(4):155-169.

DOI: 10.1093/intimm/dxy011

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The incidence of allergic diseases, which increased to epidemic proportions in developed countries over the last few decades, has been correlated with altered gut microbiota colonization. Although probiotics may play a critical role in the restoration of gut homeostasis, their efficiency in the control of allergy is controversial. Here, we aimed to investigate the effects of probiotic treatment initiated at neonatal or adult ages on the suppression of experimental ovalbumin (OVA)-induced asthma. Neonatal or adult mice were orally treated with probiotic bacteria and subjected to OVA-induced allergy. Asthma-like symptoms, microbiota composition and frequencies of the total CD4+ T lymphocytes and CD4+Foxp3+ regulatory T (Treg) cells were evaluated in both groups. Probiotic administration to neonates, but not to adults, was necessary and sufficient for the absolute prevention of experimental allergen-induced sensitization. The neonatally acquired tolerance, transferrable to probiotic-untreated adult recipients by splenic cells from tolerant donors, was associated with modulation of gut bacterial composition, augmented levels of cecum butyrate and selective accumulation of Treg cells in the airways. Our findings reveal that a cross-talk between a healthy microbiota and qualitative features inherent to neonatal T cells, especially in the Treg cell subset, might support the beneficial effect of perinatal exposure to probiotic bacteria on the development of long-term tolerance to allergens.

Echevarria-Lima J, de Abreu Pereira D, de Oliveira TS, de Melo Espíndola O, Lima MA, Celestino Leite AC, Sandim V, Rodrigues Nascimento C, E Kalume D, B Zingali R. Protein Profile of Blood Monocytes is Altered in HTLV-1 Infected Patients: Implications for HAM/TSP Disease. Sci Rep. 2018 Sep 25;8(1):14354.

DOI: 10.1038/s41598-018-32324-2

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Human T-cell lymphotropic virus type-1 (HTLV-1) is the etiological agent of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The endothelial breakdown and migration of leukocytes, including monocytes, to the spinal cord are involved in HAM/TSP development. Monocytes from HTLV-1-infected individuals exhibit important functional differences when compared to cells from uninfected donors. Using proteomic shot gun strategy, performed by nanoACQUITY-UPLC system, we analyzed monocytes isolated from peripheral blood of asymptomatic carriers (AC), HAM/TSP and uninfected individuals. 534 proteins were identified among which 376 were quantified by ExpressionE software. Our study revealed a panel of changes in protein expression linked to HTLV-1 infection. Upregulation of heat shock proteins and downregulation of canonical histone expression were observed in monocytes from HTLV-1-infected patients. Moreover, expression of cytoskeleton proteins was increased in monocytes from HTLV-1-infected patients, mainly in those from HAM/TSP, which was confirmed by flow cytometry and fluorescence microscopy. Importantly, functional assays demonstrated that monocytes from HAM/TSP patients present higher ability for adhesion and transmigration thought endothelium than those from AC and uninfected individuals. The major changes on monocyte protein profile were detected in HAM/TSP patients, suggesting that these alterations exert a relevant role in the establishment of HAM/TSP.

Kitoko JZ, de Castro LL, Nascimento AP, Abreu SC, Cruz FF, Arantes AC, Xisto DG, Martins MA, Morales MM, Rocco PRM, Olsen PC. Therapeutic administration of bone marrow-derived mesenchymal stromal cells reduces airway inflammation without up-regulating Tregs in experimental asthma. Clin Exp Allergy. 2018 Feb;48(2):205-216.  

DOI: 10.1111/cea.13048

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Prophylactic administration of mesenchymal stromal cells (MSCs) derived from adipose (AD-MSC) and bone marrow tissue (BM-MSC) in ovalbumin-induced asthma hinders inflammation in a Treg-dependent manner. It is uncertain whether MSCs act through Tregs when inflammation is already established in asthma induced by a clinically relevant allergen.

Gomes-Neto JF, Sartorius R, Canto FB, Almeida TS, Dias AA, Barbosa CD, Melo GA, Oliveira AC, Aguiar PN, Machado CR, de Matos Guedes HL, Santiago MF, Nóbrega A, De Berardinis P, Bellio M. Vaccination With Recombinant Filamentous fd Phages Against Parasite Infection Requires TLR9 Expression. Front Immunol. 2018 May 29;9:1173. 

DOI: 10.3389/fimmu.2018.01173

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Recombinant filamentous fd bacteriophages (rfd) expressing antigenic peptides were shown to induce cell-mediated immune responses in the absence of added adjuvant, being a promising delivery system for vaccination. Here, we tested the capacity of rfd phages to protect against infection with the human protozoan Trypanosoma cruzi, the etiologic agent of Chagas Disease. For this, C57BL/6 (B6) and Tlr9−/ mice were vaccinated with rfd phages expressing the OVA257–264 peptide or the T. cruzi-immunodominant peptides PA8 and TSKB20 and challenged with either the T. cruzi Y-OVA or Y-strain, respectively. We found that vaccination with rfd phages induces anti-PA8 and anti-TSKB20 IgG production, expansion of Ag-specific IFN-γ, TNF-α, and Granzyme B-producing CD8+ T cells, as well as in vivo Ag-specific cytotoxic responses. Moreover, the fd-TSKB20 vaccine was able to protect against mortality induced by a high-dose inoculum of the parasite. Although vaccination with rfd phages successfully reduced both parasitemia and parasite load in the myocardium of WT B6 mice, Tlr9−/− animals were not protected against infection. Thus, our data extend previous studies, demonstrating that rfd phages induce Ag-specific IgG and CD8+ T cell-mediated responses and confer protection against an important human parasite infection, through a TLR9-dependent mechanism.

Guimarães-Pinto K, Nascimento DO, Corrêa-Ferreira A, Morrot A, Freire-de-Lima CG, Lopes MF, DosReis GA, Filardy AA. Trypanosoma cruzi Infection Induces Cellular Stress Response and Senescence-Like Phenotype in Murine Fibroblasts. Front Immunol. 2018 Jul 9;9:1569. 

DOI: 10.3389/fimmu.2018.01569

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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 medium after 4 days of infection. Also, we found that T. cruzi infection reduced the number of fibroblasts in 3-day cell cultures, by altering fibroblast proliferation. Infected fibroblasts displayed distinctive phenotypic alterations, including enlarged and flattened morphology with a nuclei accumulation of senescence-associated heterochromatin foci. In addition, infection induced an overexpression of the enzyme senescence-associated β-galactosidase (SA-β-gal), an activation marker of the cellular senescence program, as well as the production of cytokines and chemokines involved with the senescence-associated secretory phenotype (SASP) such as IL-6, TNF-α, IL-1β, and MCP-1. Infected fibroblasts released increased amounts of stress-associated factors nitric oxide (NO) and reactive oxygen species (ROS), and the treatment with antioxidants deferoxamine (DFO) and N-acetylcysteine reduced ROS generation, secretion of SASP-related cytokine IL-6, SA-β-gal activity, and parasite load by infected fibroblasts. Taken together, our data suggest that T. cruzi infection triggers a rapid cellular stress response followed by induction of a senescent-like phenotype in NIH-3T3 fibroblasts, enabling them to act as reservoirs of parasites during the early stages of the Chagas disease.

Pinheiro TM, Mota MTO, Watanabe ASA, Biselli-Périco JM, Drumond BP, Ribeiro MR, Vedovello D, Araújo JP Jr, Pimenta PFP, Chaves BA, Silva MMCD, Batista ICA, Papa MP, Meuren LM, Lucas CGO, Matassoli FL, Gil LHVG, Bozzi A, Calzavara-Silva CE, Arruda LB, Souza DDG, Teixeira MM, Vasilakis N, Nogueira ML. Viral immunogenicity determines epidemiological fitness in a cohort of DENV-1 infection in Brazil. PLoS Negl Trop Dis. 2018 May 29;12(5):e0006525. 

DOI: 10.1371/journal.pntd.0006525

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The dynamics of dengue virus (DENV) circulation depends on serotype, genotype and lineage replacement and turnover. In São José do Rio Preto, Brazil, we observed that the L6 lineage of DENV-1 (genotype V) remained the dominant circulating lineage even after the introduction of the L1 lineage. We investigated viral fitness and immunogenicity of the L1 and L6 lineages and which factors interfered with the dynamics of DENV epidemics. The results showed a more efficient replicative fitness of L1 over L6 in mosquitoes and in human and non-human primate cell lines. Infections by the L6 lineage were associated with reduced antigenicity, weak B and T cell stimulation and weak host immune system interactions, which were associated with higher viremia. Our data, therefore, demonstrate that reduced viral immunogenicity and consequent greater viremia determined the increased epidemiological fitness of DENV-1 L6 lineage in São José do Rio Preto.

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