Fasciola hepatica infection modifies IgG1 specific immune response to foot-and-mouth disease virus induced by vaccination.

Fasciola hepatica, a worldwide distributed helminth, has a robust immunoregulatory effect in the host, increasing the susceptibility to secondary infections. Foot and mouth disease (FMD) is a highly contagious acute vesicular viral disease effectively controlled by vaccination in endemic regions. Despite the evidence of immunoregulatory effects, the impact of fasciolosis on the immune response induced by FMD vaccination in cattle has never been assessed. Our objective was to evaluate whether the infection by F. hepatica in cattle influences the long-term immunity elicited by the currently used commercial FMD-inactivated vaccines. Aberdeen Angus steers negative for F. hepatica were vaccinated twice against FMD virus (FMDV) during the first 6 months of age using a commercial oil vaccine formulated with A24/Cruzeiro and O1/Campos strains. When maternal antibodies against F. hepatica were weaned (18--20 months of age) animals were divided into groups of 12 and infected or mock-infected with 500 metacercariae/animal. Individual serum samples were collected at 0-, 28-, 59-, 87- and 157-days post-infection (dpi). Indirect ELISAs were used to detect A24/Cruzeiro specific bovine IgG and IgG subtypes. The total IgG antibody levels and avidity against FMDV did not show significant differences between all the groups. The commercial vaccine induced higher IgG2 than IgG1 titers in vaccinated animals. Anti-FMDV IgG1 levels significantly decreased in the infected group at 28 dpi. In addition, the avidity of IgG1 FMDV-specific antibodies at day 28 in the infected group was reduced compared to the control. These results show that F. hepatica infection modified anamnestic responses against FMDV, reducing serum IgG1 titers and avidity. To our knowledge, this is the first report of immune-regulation of F. hepatica altering the immune response of FMD vaccines, one of the most globally used animal vaccines.

Truncated O-glycosylation in metastatic triple-negative breast cancer reveals a gene expression signature associated with extracellular matrix and proteolysis.

Breast cancer (BC) is the leading cause of death by cancer in women worldwide. Triple-negative (TN) BC constitutes aggressive and highly metastatic tumors associated with shorter overall survival of patients compared to other BC subtypes. The Tn antigen, a glycoconjugated structure resulting from an incomplete O-glycosylation process, is highly expressed in different adenocarcinomas, including BC. It also favors cancer growth, immunoregulation, and metastasis in TNBC. This work describes the differentially expressed genes (DEGs) associated with BC aggressiveness and metastasis in an incomplete O-glycosylated TNBC cell model. We studied the transcriptome of a TNBC model constituted by the metastatic murine 4T1 cell line that overexpresses the Tn antigen due to a mutation in one of the steps of the O-glycosylation pathway. We analyzed and compared the results with the parental wild-type cell line and with a Tn-negative cell clone that was poorly metastatic and less aggressive than the 4T1 parental cell line. To gain insight into the generated expression data, we performed a gene set analysis. Biological processes associated with cancer development and metastasis, immune evasion, and leukocyte recruitment were highly enriched among functional terms of DEGs. Furthermore, different highly O-glycosylated protein-coding genes, such as mmp9, ecm1 and ankyrin-2, were upregulated in 4T1/Tn+ tumor cells. The altered biological processes and DEGs that promote tumor growth, invasion and immunomodulation might explain the aggressive properties of 4T1/Tn+ tumor cells. These results support the hypothesis that incomplete O-glycosylation that leads to the expression of the Tn antigen, which might regulate activity or interaction of different molecules, promotes cancer development and immunoregulation.

Collagen Membranes Functionalized with 150 Cycles of Atomic Layer Deposited Titania Improve Osteopromotive Property in Critical-Size Defects Created on Rat Calvaria.

The membranes used in bone reconstructions have been the object of investigation in the field of tissue engineering, seeking to improve their mechanical strength and add other properties, mainly the osteopromotive. This study aimed to evaluate the functionalization of collagen membranes, with atomic layer deposition of TiO2 on the bone repair of critical defects in rat calvaria and subcutaneous biocompatibility. A total of 39 male rats were randomized into four groups: blood clot (BC), collagen membrane (COL), COL 150-150 cycles of titania, and COL 600-600 cycles of titania. The defects were created in each calvaria (5 mm in diameter) and covered according to each group; the animals were euthanized at 7, 14, and 28 days. The collected samples were assessed by histometric (newly bone formed, soft tissue area, membrane area, and residual linear defect) and histologic (inflammatory cells and blood cells count) analysis. All data were subjected to statistical analysis (p < 0.05). The COL150 group showed statistically significant differences compared to the other groups, mainly in the analysis of residual linear defects (1.5 ± 0.5 × 106 pixels/µm2 for COL 150, and around 1 ± 0.5 × 106 pixels/µm2 for the other groups) and newly formed bone (1500 ± 1200 pixels/µm for COL 150, and around 4000 pixels/µm for the others) (p < 0.05), demonstrating a better biological behavior in the chronology of defects repair. It is concluded that the collagen membrane functionalized by TiO2 over 150 cycles showed better bioactive potential in treating critical size defects in the rats' calvaria.

Identification of Neotropical Culex Mosquitoes by MALDI-TOF MS Profiling.

The mosquito (Diptera: Culicidae) fauna of French Guiana encompasses 242 species, of which nearly half of them belong to the genus Culex. Whereas several species of Culex are important vectors of arboviruses, only a limited number of studies focus on them due to the difficulties to morphologically identify field-caught females. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been reported as a promising method for the identification of mosquitoes. Culex females collected in French Guiana were morphologically identified and dissected. Abdomens were used for molecular identification using the COI (cytochrome oxidase 1) gene. Legs and thorax of 169 specimens belonging to 13 Culex species, (i.e., Cx. declarator, Cx. nigripalpus, Cx. quinquefasciatus, Cx. usquatus, Cx. adamesi, Cx. dunni, Cx. eastor, Cx. idottus, Cx. pedroi, Cx. phlogistus, Cx. portesi, Cx. rabanicolus and Cx. spissipes) were then submitted to MALDI-TOF MS analysis. A high intra-species reproducibility and inter-species specificity of MS spectra for each mosquito body part tested were obtained. A corroboration of the specimen identification was revealed between MALDI-TOF MS, morphological and molecular results. MALDI-TOF MS protein profiling proves to be a suitable tool for identification of neotropical Culex species and will permit the enhancement of knowledge on this highly diverse genus.

Advertising and Psychology: Strategies to Reduce Violence Against Women / Publicidade e Psicologia: Estratégias de Redução da Violência Contra a Mulher / Publicidad y Psicología: Estrategias de Reducción de la Violencia Contra la Mujer

Abstract The COVID-19 exacerbated violence against women. This study evaluated the possible efficacy of using advertising pieces containing the hypocrisy paradigm, the contrast principle, and moral disengagement mechanisms to prevent and reduce violence against women. We conducted two studies which included exclusively men as participants. Study 1 (n=400; M age =21.69; Me=20.00; SD=5.79) used traditional pieces on violence against women, manipulating only their moral disengagement phrases. Results suggest that the phrase combined with traditional images is either ineffective or has a rebound effect. Study 2 (n=303; M age =21.38; Me=20.00; SD=4.94) manipulated the image in Study 1, showing more effective results regarding hostility. However, physical aggression showed no significant differences. Finally, some pieces generated a rebound effect, increasing participants' self-perception of aggression. The use of advertising can act as an ally or an enemy of public policies if their effectiveness lacks proper testing.

Resumo A violência contra mulheres é um problema pandêmico agravado pela COVID-19. Esta pesquisa objetivou verificar a eficácia de peças publicitárias em reduzir a violência contra mulheres por meio do paradigma de hipocrisia, o princípio de contraste e os mecanismos de desengajamento moral. Realizaram-se dois estudos com amostras masculinas. O Estudo 1 (n=400; M idade =21,69; Me=20,00; DP=5,79) utilizou peças tradicionais, manipulando apenas as frases de desengajamento moral. O resultado sugere que a frase combinada com imagens tradicionais são ineficazes ou geram efeito rebote. O Estudo 2 (n=303; M idade =21,38; Me=20,00; DP=4,94) manipulou a imagem e os resultados indicam maior efetividade das peças em relação à hostilidade. Entretanto, a agressão física não demonstrou diferenças significativas. Finalmente, algumas peças geraram efeito rebote, levando ao incremento da autopercepção de agressividade dos participantes. O uso da publicidade pode prejudicar políticas públicas de combate a violência contra mulheres quando sua eficácia não é devidamente testada.

Resumen La violencia contra la mujer es un problema pandémico agravado por el COVID-19. Esta investigación verificó el grado de eficacia de anuncios publicitarios para reducir la violencia contra la mujer utilizando el paradigma de la hipocresía, el principio de contraste y los mecanismos de desconexión moral. Se diseñaron dos estudios con muestras masculinas. El Estudio 1 (n=400; M edad =21,69; Me=20,00; DT=5,79) utilizó anuncios tradicionales, manipulando únicamente las frases de desconexión moral. El resultado sugiere que la frase combinada con imágenes tradicionales es ineficaz o tiene efecto rebote. El Estudio 2 (n=303; M edad =21,38, Me=20,00; DT=4,94) manipuló la imagen, y los resultados indican mayor eficacia respecto a la hostilidad. Pero la agresión física no mostró diferencias significativas. Finalmente, algunos anuncios generaron efecto rebote, incrementando la autopercepción de la agresividad. Así, el uso de la publicidad puede actuar como enemiga de las políticas públicas contra la violencia a la mujer cuando no se comprueba adecuadamente su eficacia.

Rede e apoio social no cuidado de crianças com Síndrome de Down / Social network and support in care for children with Down Syndrome / Red y apoyo social en el cuidado de niños con Síndrome de Down

Objetivo: descrever a rede social e o tipo de apoio recebido por cuidadores de crianças com Síndrome de Down. Método: estudo descritivo com abordagem qualitativa com base no referencial metodológico de Sanicola. Para análise das entrevistas utilizou-se a técnica de análise de conteúdo de Bardin. Protocolo de pesquisa aprovado pelo Comitê de Ética em Pesquisa. Resultados: as redes sociais dos cuidadores entrevistados são predominantemente pequenas, pouco densas, marcadas por fortes relações com familiares e amigos. Na análise das falas foram identificadas três categorias: apoio emocional da família, suporte emocional e financeiro dos amigos e insatisfação com o serviço de saúde. Considerações finais: a abordagem da temática pelo profissional de saúde, principalmente o enfermeiro, faz-se necessária para o conhecimento das relações e como elas se estabelecem, de forma a fortalecer vínculos e realizar intervenções que visem uma melhor qualidade de vida para os cuidadores de crianças com Síndrome de Down.

Objective: to describe the social networks of caregivers of children with Down Syndrome and the type of support they received. Method: in this qualitative, descriptive study, framed by Sanicola's methodology, interviews were analyzed using Bardin content analysis. The research protocol was approved by the research ethics committee. Results: the social networks of the caregivers interviewed were predominantly small, not very dense, and featured strong relationships with family and friends. From analysis of the interviews, three categories were identified: emotional support from the family; emotional and financial support from friends; and dissatisfaction with the health service. Final remarks: it is necessary that health personnel, particularly nurses, address the subject in order to discover the relationships and how they are established, so as to strengthen bonds and carry out interventions to improve quality of life for caregivers of children with Down Syndrome.

Objetivo: describir la red social y el tipo de apoyo que reciben los cuidadores de niños con Síndrome de Down. Método: estudio descriptivo con enfoque cualitativo con base en el marco metodológico de Sanicola. Para analizar las entrevistas se utilizó la técnica de análisis de contenido de Bardin. Protocolo de investigación aprobado por el Comité de Ética en Investigación. Resultados: las redes sociales de los cuidadores entrevistados son predominantemente pequeñas, poco densas, marcadas por fuertes relaciones con familiares y amigos. En el análisis de los discursos, se identificaron tres categorías: apoyo emocional de la familia, apoyo emocional y económico de los amigos e insatisfacción con el servicio de salud. Consideraciones finales: el enfoque del tema por parte del profesional de la salud, especialmente del enfermero, se vuelve necesario para conocer las relaciones y cómo estas se establecen, con el fin de fortalecer vínculos y realizar intervenciones dirigidas a una mejor calidad de vida de los cuidadores de niños con Síndrome de Down.

Lung Tumor Cells with Different Tn Antigen Expression Present Distinctive Immunomodulatory Properties.

Lung cancer is the first leading cause of cancer-related deaths in the world. Aberrant glycosylation in lung tumors leads to the expression of tumor-associated carbohydrate structures, such as the Tn antigen, consisting of N-acetyl-galactosamine (GalNAc) linked to a serine or threonine residue in proteins (α-GalNAc-O-Ser/Thr). The Tn antigen can be recognized by the Macrophage Galactose/GalNAc lectin (MGL), which mediates various immune regulatory and tolerogenic functions, mainly by reprogramming the maturation of function of dendritic cells (DCs). In this work, we generated two different Tn-expressing variants from the Lewis-type lung murine cancer cell line LL/2, which showed different alterations in the O-glycosylation pathways that influenced the interaction with mouse MGL2 and the immunomodulatory properties of DCs. Thus, the identification of the biological programs triggered by Tn+ cancer cells might contribute to an improved understanding of the molecular mechanisms elicited by MGL-dependent immune regulatory circuits.

Immunophenotypic Analysis of T Lymphocytes and Cytokine Production in Elderly Practicing Physical Activities and Its Relationship with Quality of Life and Depression.

Aging is a complex process often associated with a chronic inflammatory profile that alters several biological functions, including the immune system and cognitive and physical capacity. The practice of physical activity is increasingly gaining popularity as a method of preventing infections, depression, and other disorders that affect the quality of life of the elderly. Thus, this work analyzes the profile of cytokines and molecular markers expressed in immune cells of elderly people who practice physical activities or not, evaluating their impacts on the immune system and quality of life. For this, 48 individuals were recruited, and peripheral blood samples were collected for hemogram analysis, cytokine determination, and immunophenotyping. Elderly people were separated into two groups: practitioners with low-intensity physical activity and non-practitioners. Quality of life was assessed using the Whoqol-Old instrument, and depression was assessed using the Beck II Depression Inventory. When comparing the scores of the Whoqol-Old and Beck questionnaires, we observed a significant negative correlation between these two factors. The perception of a higher quality of life was present in the elderly who exercised and was related to greater autonomy and sensory abilities, whereas the presence of depression was lower. In the hemogram, we observed higher basophil and segmented counts in the sedentary elderly, whereas lymphocytes and monocytes had lower counts. Elderly practitioners of physical activities had higher levels of IFN-γ, IL-4, and IL-10; increased expression of CD69, PD1, and TIM-3 in CD4+ T lymphocytes and increased CD14+CD80+ and CD14+CD86+ monocytes. Elderly people with an increased perception of quality of life had higher levels of IFN-γ, higher expression of CD14+CD80+CD86+, and decreased levels of TRAIL. An increase in TRAIL was observed in individuals with depression, in addition to an increased expression of CD14+CD86+. These results show a clear correlation between the quality of life, level of depression, physical activity, and immune system function. Although some cytokines with a typical proinflammatory profile (IFN-γ) were observed, the results point to a protective state with benefits reflected in the general well-being of the elderly who exercise.

Macrophage Gal/GalNAc lectin 2 (MGL2)+ peritoneal antigen presenting cells during Fasciola hepatica infection are essential for regulatory T cell induction.

Fasciola hepatica, one of the agents that causes fasciolosis, modulates the host immune system to allow parasite survival in the host. F. hepatica expresses carbohydrate-containing glycoconjugates that are decoded by C-type lectin receptors, such as Dectin-1, mannose receptor, DC-SIGN and MGL, that are mainly present on myeloid antigen presenting cells (APCs) and can mediate immunoregulatory properties on T cells. In particular, Macrophage Gal/GalNAc lectin 2 (MGL2) expands modified Th2 immune responses, while suppressing Th1 polarization, upon recognition of GalNAc-glycosylated parasite components. In this study, by using MGL2-DTR transgenic mice that encode human diphtheria toxin receptor in MGL2+ cells, we demonstrate the role of peritoneal APCs during F. hepatica infection in favoring parasite survival. This process might be mediated by the induction of splenic Tregs in vivo, since the depletion of MGL2+ cells conferred mice with partial resistance to the infection and abrogated the increase of CD4+/CD25+ FoxP3+ Tregs induced by the parasite. Therefore, MGL2+ cells are critical determinants of F. hepatica infection and could constitute immune checkpoints to control parasite infection.

Enhanced procedures for mosquito identification by MALDI-TOF MS.

BACKGROUND: In the last decade, an innovative approach has emerged for arthropod identification based on matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Increasing interest in applying the original technique for arthropod identification has led to the development of a variety of procedures for sample preparation and selection of body parts, among others. However, the absence of a consensual strategy hampers direct inter-study comparisons. Moreover, these different procedures are confusing to new users. Establishing optimized procedures and standardized protocols for mosquito identification by MALDI-TOF MS is therefore a necessity, and would notably enable the sharing of reference MS databases. Here, we assess the optimal conditions for mosquito identification using MALDI-TOF MS profiling. METHODS: Three homogenization methods, two of which were manual and one automatic, were used on three distinct body parts (legs, thorax, head) of two mosquito laboratory strains, Anopheles coluzzii and Aedes aegypti, and the results evaluated. The reproducibility of MS profiles, identification rate with relevant scores and the suitability of procedures for high-throughput analyses were the main criteria for establishing optimized guidelines. Additionally, the consequences of blood-feeding and geographical origin were evaluated using both laboratory strains and field-collected mosquitoes. RESULTS: Relevant score values for mosquito identification were obtained for all the three body parts assayed using MALDI-TOF MS profiling; however, the thorax and legs were the most suitable specimens, independently of homogenization method or species. Although the manual homogenization methods were associated with a high rate of identification on the three body parts, this homogenization mode is not adaptable to the processing of a large number of samples. Therefore, the automatic homogenization procedure was selected as the reference homogenization method. Blood-feeding status did not hamper the identification of mosquito species, despite the presence of MS peaks from original blood in the MS profiles of the three body parts tested from both species. Finally, a significant improvement in identification scores was obtained for field-collected specimens when MS spectra of species from the same geographical area were added to the database. CONCLUSION: The results of the current study establish guidelines for the selection of mosquito anatomic parts and modality of sample preparation (e.g. homogenization) for future specimen identification by MALDI-TOF MS profiling. These standardized operational protocols could be used as references for creating an international MS database.

Liver function markers and haematological dynamics during acute and chronic phases of experimental Fasciola hepatica infection in cattle treated with triclabendazole.

Fasciola hepatica, a worldwide-distributed liver fluke, is one of the causative agents of fasciolosis, a zoonotic disease that affects livestock and humans. In livestock, fasciolosis causes huge economic losses worldwide, reducing animal fertility, milk production, weight gain and condemnation of livers. In spite of the availability of drugs, such as triclabendazole (TCZ), for the treatment of fasciolosis, they do not necessarily prevent liver damage or parasite reinfection and can eventually increase parasite resistance. The aim of this research was to relate the hepatic function, haematological parameters, leukocyte counts in circulation and parasite egg shedding during F. hepatica acute and chronic phases of infection in cattle as well as to determine how these parameters change with TCZ-treatment of chronically infected cattle. Our results show that increased levels of serum aspartate aminotransferase (AST) and gamma glutamyltransferase (GGT) were detected in early stages of the experimental infection. Moreover, high circulating eosinophil count and plateletcrit levels were correlated with fluke number in livers from infected cattle. On the other hand, although TCZ-treatment in the chronic phase of infection reduced parasite burden and damage in the liver, it was not able to completely avoid them. In conclusion, our work sheds light into the physiopathological mechanisms induced during fluke infection in cattle, revealing the complexity of the host response to the infection, together with the effects of TCZ-treatment in chronically infected animals.

Exploratory Study on Application of MALDI-TOF-MS to Detect SARS-CoV-2 Infection in Human Saliva.

SARS-CoV-2 has caused a large outbreak since its emergence in December 2019. COVID-19 diagnosis became a priority so as to isolate and treat infected individuals in order to break the contamination chain. Currently, the reference test for COVID-19 diagnosis is the molecular detection (RT-qPCR) of the virus from nasopharyngeal swab (NPS) samples. Although this sensitive and specific test remains the gold standard, it has several limitations, such as the invasive collection method, the relative high cost and the duration of the test. Moreover, the material shortage to perform tests due to the discrepancy between the high demand for tests and the production capacities puts additional constraints on RT-qPCR. Here, we propose a PCR-free method for diagnosing SARS-CoV-2 based on matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) profiling and machine learning (ML) models from salivary samples. Kinetic saliva samples were collected at enrollment and ten and thirty days later (D0, D10 and D30), to assess the classification performance of the ML models compared to the molecular tests performed on NPS specimens. Spectra were generated using an optimized protocol of saliva collection and successive quality control steps were developed to ensure the reliability of spectra. A total of 360 averaged spectra were included in the study. At D0, the comparison of MS spectra from SARS-CoV-2 positive patients (n = 105) with healthy healthcare controls (n = 51) revealed nine peaks that significantly distinguished the two groups. Among the five ML models tested, support vector machine with linear kernel (SVM-LK) provided the best performance on the training dataset (accuracy = 85.2%, sensitivity = 85.1%, specificity = 85.3%, F1-Score = 85.1%). The application of the SVM-LK model on independent datasets confirmed its performances with 88.9% and 80.8% of correct classification for samples collected at D0 and D30, respectively. Conversely, at D10, the proportion of correct classification had fallen to 64.3%. The analysis of saliva samples by MALDI-TOF MS and ML appears as an interesting supplementary tool for COVID-19 diagnosis, despite the mitigated results obtained for convalescent patients (D10).

The tumor-associated Tn antigen fosters lung metastasis and recruitment of regulatory T cells in triple negative breast cancer.

Cancer is a leading cause of death worldwide, accounting for nearly 10 million deaths. Among breast cancers (BC) subtypes, triple-negative (TN) BC is characterized by metastatic progression and poor patient prognosis. Although, TNBC is initially sensitive to chemotherapy, many TNBC patients rapidly develop resistance, at which point metastatic disease is highly lethal. Cancer cells present phenotypic changes or molecular signatures that distinguish them from healthy cells. The Tn antigen (GalNAc-O-Thr/Ser), which constitutes a powerful tool as tumor marker, was recently reported to contribute to tumor growth. However, its role in BC-derived metastasis has not yet been addressed. In this work, we generated a pre-clinical orthotopic Tn+ model of metastatic TNBC, which mimics the patient surgical treatment and is useful to study the role of Tn in metastasis and immunoregulation. We obtained two different cell clones, which differed in their Tn antigen expression: a high Tn-expressing and a non-expressing clone. Interestingly, the Tn-positive cell line generated significantly larger tumors and higher degree of lung metastases associated with a lower survival rate than the Tn-negative and parental cell line. Furthermore, we also found that both tumors and draining-lymph nodes from Tn+-tumor-bearing mice presented a higher frequency of CD4+ FoxP3+ T cells, while their splenocytes expressed higher levels of IL-10. In conclusion, this work suggests that the Tn antigen participates in breast tumor growth and spreading, favoring metastases to the lungs that are associated with an immunoregulatory state, suggesting that Tn-based immunotherapy could be a strategy of choice to treat these tumors.

Heme-Oxygenase-1 Attenuates Oxidative Functions of Antigen Presenting Cells and Promotes Regulatory T Cell Differentiation during Fasciola hepatica Infection.

Fasciola hepatica is a fluke that infects livestock and humans causing fasciolosis, a zoonotic disease of increasing importance due to its worldwide distribution and high economic losses. The parasite regulates the host immune system by inducing a strong Th2 and regulatory T (Treg) cell immune response through mechanisms that might involve the expression or activity of heme-oxygenase-1 (HO-1), the rate-limiting enzyme in the catabolism of free heme that also has immunoregulatory and antioxidant properties. In this paper, we show that F. hepatica-infected mice upregulate HO-1 on peritoneal antigen-presenting cells (APC), which produce decreased levels of both reactive oxygen and nitrogen species (ROS/RNS). The presence of these cells was associated with increased levels of regulatory T cells (Tregs). Blocking the IL-10 receptor (IL-10R) during parasite infection demonstrated that the presence of splenic Tregs and peritoneal APC expressing HO-1 were both dependent on IL-10 activity. Furthermore, IL-10R neutralization as well as pharmacological treatment with the HO-1 inhibitor SnPP protected mice from parasite infection and allowed peritoneal APC to produce significantly higher ROS/RNS levels than those detected in cells from infected control mice. Finally, parasite infection carried out in gp91phox knockout mice with inactive NADPH oxidase was associated with decreased levels of peritoneal HO-1+ cells and splenic Tregs, and partially protected mice from the hepatic damage induced by the parasite, revealing the complexity of the molecular mechanisms involving ROS production that participate in the complex pathology induced by this helminth. Altogether, these results contribute to the elucidation of the immunoregulatory and antioxidant role of HO-1 induced by F. hepatica in the host, providing alternative checkpoints that might control fasciolosis.

Optimization and Standardization of Human Saliva Collection for MALDI-TOF MS.

SARS-CoV-2 outbreak led to unprecedented innovative scientific research to preclude the virus dissemination and limit its impact on life expectancy. Waiting for the collective immunity by vaccination, mass-testing, and isolation of positive cases remain essential. The development of a diagnosis method requiring a simple and non-invasive sampling with a quick and low-cost approach is on demand. We hypothesized that the combination of saliva specimens with MALDI-TOF MS profiling analyses could be the winning duo. Before characterizing MS saliva signatures associated with SARS-CoV-2 infection, optimization and standardization of sample collection, preparation and storage up to MS analyses appeared compulsory. In this view, successive experiments were performed on saliva from healthy healthcare workers. Specimen sampling with a roll cotton of Salivette® devices appeared the most appropriate collection mode. Saliva protein precipitation with organic buffers did not improved MS spectra profiles compared to a direct loading of samples mixed with acetonitrile/formic acid buffer onto MS plate. The assessment of sample storage conditions and duration revealed that saliva should be stored on ice until MS analysis, which should occur on the day of sampling. Kinetic collection of saliva highlighted reproducibility of saliva MS profiles over four successive days and also at two-week intervals. The intra-individual stability of saliva MS profiles should be a key factor in the future investigation for biomarkers associated with SARS-CoV-2 infection. However, the singularity of MS profiles between individuals will require the development of sophisticated bio-statistical analyses such as machine learning approaches. MALDI-TOF MS profiling of saliva could be a promising PCR-free tool for SARS-CoV-2 screening.

Mouth Washing Impaired SARS-CoV-2 Detection in Saliva.

BACKGROUND: A previous study demonstrated the performance of the Salivette® (SARSTEDT, Numbrecht, Germany) as a homogeneous saliva collection system to diagnose COVID-19 by RT-qPCR, notably for symptomatic and asymptomatic patients. However, for convalescent patients, the corroboration of molecular detection of SARS-CoV-2 in paired nasopharyngeal swabs (NPS) and saliva samples was unsatisfactory. OBJECTIVES: The aim of the present work was to assess the concordance level of SARS-CoV-2 detection between paired sampling of NPSs and saliva collected with Salivette® at two time points, with ten days of interval. RESULTS: A total of 319 paired samples from 145 outpatients (OP) and 51 healthcare workers (HW) were collected. Unfortunately, at day ten, 73 individuals were lost to follow-up, explaining some kinetic missing data. Due to significant waiting rates at hospitals, most of the patients ate and/or drank while waiting for their turn. Consequently, mouth washing was systematically proposed prior to saliva collection. None of the HW were diagnosed as SARS-CoV-2 positive using NPS or saliva specimens at both time points (n = 95) by RT-qPCR. The virus was detected in 56.3% (n = 126/224) of the NPS samples from OP, but solely 26.8% (n = 60/224) of the paired saliva specimens. The detection of the internal cellular control, the human RNase P, in more than 98% of the saliva samples, underlined that the low sensitivity of saliva specimens (45.2%) for SARS-CoV-2 detection was not attributed to an improper saliva sample storing or RNA extraction. CONCLUSIONS: This work revealed that mouth washing decreased viral load of buccal cavity conducting to impairment of SARS-CoV-2 detection. Viral loads in saliva neo-produced appeared insufficient for molecular detection of SARS-CoV-2. At the time when saliva tests could be a rapid, simple and non-invasive strategy to assess large scale schoolchildren in France, the determination of the performance of saliva collection becomes imperative to standardize procedures.

The Tn antigen promotes lung tumor growth by fostering immunosuppression and angiogenesis via interaction with Macrophage Galactose-type lectin 2 (MGL2).

Tn is a tumor-associated carbohydrate antigen that constitutes both a diagnostic tool and an immunotherapeutic target. It originates from interruption of the mucin O-glycosylation pathway through defects involving, at least in part, alterations in core-1 synthase activity, which is highly dependent on Cosmc, a folding chaperone. Tn antigen is recognized by the Macrophage Galactose-type Lectin (MGL), a C-type lectin receptor present on dendritic cells and macrophages. Specific interactions between Tn and MGL shape anti-tumoral immune responses by regulating several innate and adaptive immune cell programs. In this work, we generated and characterized a variant of the lung cancer murine cell line LL/2 that expresses Tn by mutation of the Cosmc chaperone gene (Tn+ LL/2). We confirmed Tn expression by lectin glycophenotyping and specific anti-Tn antibodies, verified abrogation of T-synthase activity in these cells, and confirmed its recognition by the murine MGL2 receptor. Interestingly, Tn+ LL/2 cells were more aggressive in vivo, resulting in larger and highly vascularized tumors than those generated from wild type Tn- LL/2 cells. In addition, Tn+ tumors exhibited an increase in CD11c+ F4/80+ cells with high expression of MGL2, together with an augmented expression of IL-10 in infiltrating CD4+ and CD8+ T cells. Importantly, this immunosuppressive microenvironment was dependent on the presence of MGL2+ cells, since depletion of these cells abrogated tumor growth, vascularization and recruitment of IL-10+ T cells. Altogether, our results suggest that expression of Tn in tumor cells and its interaction with MGL2-expressing CD11c+F4/80+ cells promote immunosuppression and angiogenesis, thus favoring tumor progression.

Salivette, a relevant saliva sampling device for SARS-CoV-2 detection.

Background: The gold standard for COVID-19 diagnosis relies on quantitative reverse-transcriptase polymerase-chain reaction (RT-qPCR) from nasopharyngeal swab (NPS) specimens, but NPSs present several limitations. The simplicity, low invasive and possibility of self-collection of saliva imposed these specimens as a relevant alternative for SARS-CoV-2 detection. However, the discrepancy of saliva test results compared to NPSs made of its use controversial. Here, we assessed Salivettes®, as a standardized saliva collection device, and compared SARS-CoV-2 positivity on paired NPS and saliva specimens. Methods: A total of 303 individuals randomly selected among those investigated for SARS-CoV-2 were enrolled, including 30 (9.9%) patients previously positively tested using NPS (follow-up group), 90 (29.7%) mildly symptomatic and 183 (60.4%) asymptomatic. Results: The RT-qPCR revealed a positive rate of 11.6% (n = 35) and 17.2% (n = 52) for NPSs and saliva samples, respectively. The sensitivity and specificity of saliva samples were 82.9% and 91.4%, respectively, using NPS as reference. The highest proportion of discordant results concerned the follow-up group (33.3%). Although the agreement exceeded 90.0% in the symptomatic and asymptomatic groups, 17 individuals were detected positive only in saliva samples, with consistent medical arguments. Conclusion Saliva collected with Salivette® was more sensitive for detecting symptomatic and pre-symptomatic infections.

High larvicidal efficacy of yeast-encapsulated orange oil against Aedes aegypti strains from Brazil.

BACKGROUND: Botanical substances such as essential oils (EOs) have demonstrated insecticidal properties and are a valid option for vector control. However, free EOs are unreliable as mosquito larvicides due their easy degradation by environmental exposure to ultraviolet light and higher temperatures. Here, we assessed the efficacy of a mosquito larvicide based on orange oil in a yeast-based delivery system against Aedes aegypti strains with different resistance status towards chemical neurotoxic insecticides. This larvicide preparation was physicochemically characterized in a previous report. METHODS: Larvae of four Ae. aegypti strains from different regions of Brazil and different resistance profiles for deltamethrin (pyrethroid) and temephos (organophosphate) were tested against yeast-encapsulated orange oil (YEOO) in laboratory conditions for measurement of LC50 and LC90 values. The same assays were performed with the Belo Horizonte strain under environmental conditions (natural light and temperature). The resistance profiles of these strains were compared to the Rockefeller reference strain in all conditions. RESULTS: YEOO was found to be a highly active larvicide (LC50 < 50 mg/L) against all Ae. aegypti strains tested in both laboratory conditions (LC50 = 8.1-24.7 mg/L) and environmental conditions with natural light and temperature fluctuation (LC50 = 20.0-49.9 mg/L). Moreover, all strains were considered susceptible (RR < 5) to YEOO, considering resistance ratios calculated based on the Rockefeller strain. The resistance ratios were only higher than 2.5 for LC90-95 of Belo Horizonte in the laboratory, probably due the higher heterogeneity associated with older egg papers (> 5 months). CONCLUSION: YEOO demonstrates high larvicidal activity against Ae. aegypti strains with resistant phenotypes for deltamethrin (PY) and temephos (OP). This larvicidal activity suggests the potential for the development of YEOO as an alternative intervention to synthetic insecticides in integrated vector management programs, for populations with resistance to commonly used insecticides.

Insecticide resistance and underlying targets-site and metabolic mechanisms in Aedes aegypti and Aedes albopictus from Lahore, Pakistan.

Insecticide resistant Aedes populations have recently been reported in Pakistan, imposing a threat to their control. We aimed to evaluate the susceptibility of Aedes aegypti and Aedes albopictus populations from Lahore to WHO-recommended insecticides and to investigate metabolic and target-site resistance mechanisms. For this purpose, we first carried out bioassays with the larvicides temephos and pyriproxyfen, and the adulticides malathion, permethrin, deltamethrin, alpha-cypermethrin, and etofenprox. We looked for Knockdown resistance mutations (kdr) by qPCR, High-Resolution Melt (HRM), and sequencing. In order to explore the role of detoxifying enzymes in resistance, we carried out synergist bioassay with both species and then checked the expression of CYP9M6, CYP9J10, CYP9J28, CYP6BB2, CCAe3a, and SAP2 genes in Ae. aegypti. Both species were susceptible to organophosphates and the insect growth regulator, however resistant to all pyrethroids. We are reporting the kdr haplotypes 1520Ile + 1534Cys and T1520 + 1534Cys in high frequencies in Ae. aegypti while Ae. albopictus only exhibited the alteration L882M. PBO increased the sensitivity to permethrin in Ae. aegypti, suggesting the participation of P450 genes in conferring resistance, and indeed, CYP928 was highly expressed. We presume that dengue vectors in Lahore city are resistant to pyrethroids, probably due to multiple mechanisms, such as kdr mutations and P450 overexpression.