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The SARS-CoV-2 P.1 variant, responsible for an outbreak in Manaus, Brazil, is distinguished by 12 amino acid differences in the S protein, potentially increasing its ACE-2 affinity and immune evasion capability. We investigated the innate immune response of this variant compared to the original B.1 strain, particularly concerning cytokine production. Blood samples from three severe COVID-19 patients were analyzed post-infection with both strains. Results showed no significant difference in cytokine production of mononuclear cells and neutrophils for either variant. While B.1 had higher cytopathogenicity, neither showed viral replication in mononuclear cells. Structural analyses of the S protein highlighted physicochemical variations, which might be linked to the differences in infectivity between the strains. Our studies point to the increased infectivity of P.1 could stem from altered immunogenicity and receptor-binding affinity.

Cancer cells are characterized by metabolic reprogramming, which enables their survival in of-ten inhospitable conditions. A very well-documented example that has gained attraction in re-cent years and is already considered a hallmark of transformed cells is the reprogramming of carbohydrate metabolism. Such a feature, in association with the differential expression of en-zymes involved in the biosynthesis of glycoconjugates, generically known as glycosyltransfer-ases, contributes to the expression of structurally atypical glycans when compared to those ex-pressed in healthy tissues. The latest studies have demonstrated that glycophenotypic alterations are capable of modulating multifactorial events essential for the development and/or progres-sion of the disease. Herein, we will address the importance of glycobiology in modern medi-cine, focusing on the ability of unusual/truncated O -linked glycans to modulate two complex and essential phenomena for cancer progression: the acquisition of the multidrug resistance (MDR) phenotype and the activation of molecular pathways associated with the epithelial-mesenchymal transition (EMT) process, an event deeply linked with cancer metastasis.

The interactions between cell and cellular matrix confers plasticity to each body tissue, influencing the cellular migratory capacity. Macrophages rely on motility to promote their physiological function. These phagocytes are determinant for the control of invasive infections, and their immunological role largely depends on their ability to migrate and adhere to tissue. Therefore, they interact with the components of the extracellular matrix through their adhesion receptors, conferring morphological modifications that change their shape during migration. Nevertheless, the need to use in vitro cell growth models with the conditioning of three-dimensional synthetic matrices to mimic the dynamics of cell-matrix interaction has been increasingly studied. This becomes more important to effectively understand the changes occurring in phagocyte morphology in the context of infection progression, such as in Chagas disease. This disease is caused by the intracellular pathogen Trypanosoma cruzi , capable of infecting macrophages, determinant cells in the anti-trypanosomatid immunity. In the present study, we sought to understand how an in vitro extracellular matrix model interferes with T. cruzi infection in macrophages. Using different time intervals and parasite ratios, we evaluated the cell morphology and parasite replication rate in the presence of 3D collagen I matrix. Nevertheless, microscopy techniques such as scanning electron microscopy were crucial to trace macrophage-matrix interactions. In the present work, we demonstrated for the first time that the macrophage-matrix interaction favors T. cruzi in vitro replication and the release of anti-inflammatory cytokines during macrophage infection, in addition to drastically altering the morphology of the macrophages and promoting the formation of migratory macrophages.

In this article, we discuss the main aspects regarding the recognition of cell surface glycoconjugates and the immunomodulation of responses against the progression of certain pathologies, such as cancer and infectious diseases. In the first part, we talk about different aspects of glycoconjugates and delve deeper into the importance of N-glycans in cancer immunotherapy. Then, we describe two important lectin families that have been very well studied in the last 20 years. Examples include the sialic acid-binding immunoglobulin (Ig)-like lectins (siglecs), and galectins. Finally, we discuss a topic that needs to be better addressed in the field of glycoimmunology: the impact of oncofetal antigens on the cells of the immune system. New findings in this area are of great importance for advancement, especially in the field of oncology, since it is already known that cellular interactions mediated by carbohydrate-carbohydrate and/or carbohydrate proteins are able to modulate the progression of different types of cancer in events that compromise the functionality of the immune responses.

Human trypanosomiasis affects nearly eight million people worldwide, causing great economic and social impact, mainly in endemic areas. T. cruzi and T. brucei are protozoan parasites that present efficient mechanisms of immune system evasion, leading to disease chronification. Currently, there is no vaccine, and chemotherapy is effective only in the absence of severe clinical manifestations. Nevertheless, resistant phenotypes to chemotherapy have been described in protozoan parasites, associated with cross-resistance to other chemically unrelated drugs. Multidrug resistance is multifactorial, involving: (i) drug entry, (ii) activation, (iii) metabolism and (iv) efflux pathways. In this context, ABC transporters, initially discovered in resistant tumor cells, have drawn attention in protozoan parasites, owing to their ability to decrease drug accumulation, thus mitigating their toxic effects. The discovery of these transporters in the Trypanosomatidae family started in the 1990s; however, few members were described and functionally characterized. This review contains a brief history of the main ABC transporters involved in resistance that propelled their investigation in Trypanosoma species, the main efflux modulators, as well as ABC genes described in T. cruzi and T. brucei according to the nomenclature HUGO. We hope to convey the importance that ABC transporters play in parasite physiology and chemotherapy resistance.

Objective: to analyze perceptions of the Family Health Strategy (FHS) professional team about mental health-disorder and to identify health actions developed by the team for people with mental disorders., Method: a qualitative study of a Marxist theoretical framework and a dialectical method. 99 FHS middle and higher level professionals from São Paulo participated. Semi-structured interviews were conducted. Data were submitted to ALCESTE software and Thematic Content Analysis., Results: there were three empirical categories: Training in Mental Health; Perception of the FHS professional about mental health-disorder; and Health actions developed by the FHS team with people with mental disorders. Actions that converge and diverge from the psychosocial care model were identified., Final Considerations: there is an effort from professionals to work according to the psychosocial care model, but it is necessary to invest in the Permanent Education in Health of these professionals to overcome barriers and foster successful territorial actions.

Background: Coumarin derivatives as dihydrocoumarins have been reported to have multiple biological activities, such as antioxidant and anti-inflammatory properties. Apocynin (APO), which is a substituted-methoxy-catechol, is the most commonly used inhibitor of the multienzymatic complex NADPH-oxidase., Objective: To increase the potency of APO as an NADPH oxidase inhibitor and its antioxidant and anti-inflammatory activities, we synthesized a compound by combining the structural features of a dihydrocoumarin and APO., Method: The dihydrocoumarin-apocynin derivative (HCA) was synthesized and evaluated in antioxidant and cell-based bioassays and compared with APO., Results: We found that HCA (IC50 = 10 µM) acted as an inhibitor of NADPH oxidase (ex vivo assays) and was more potent than APO (EC50 10 µM). The inhibitory effect on NADPH oxidase was not related to simple radical scavenger activity. HCA was also a more effective radical scavenger than APO, as verified in the DPPH (EC50 = 50.3 versus EC50100 µM), triene degradation (slope AUC/concentration 759 ± 100 versus 101 ± 15) and FRAP (slope 0.159 versus 0.015) assays. The tested compound demonstrated a similar activity as an inhibitor of the oxidative damage provoked by peroxyl radicals in erythrocyte membranes., Conclusion: HCA showed superior capacity as inhibitor of NADPH oxidase and antioxidant activity. These findings show that HCA could be an improved substitute for APO and deserves further in vivo anti-inflammatory studies., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)