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The limited availability of efficient treatments for Candida infections and the increased emergence of antifungal-resistant strains stimulates the search for new antifungal agents. We have previously isolated a sunflower mannose-binding lectin (Helja) with antifungal activity against Candida albicans, capable of binding mannose-bearing oligosaccharides exposed on the cell surface. This work aimed to investigate the biological and biophysical basis of Helja's binding to C. albicans cell wall mannans and its influence on the fungicidal activity of the lectin. We evaluated the interaction of Helja with the cell wall mannans extracted from the isogenic parental strain (WT) and a glycosylation-defective C. albicans with altered cell wall phosphomannosylation (mnn4∆ null mutants) and investigated its antifungal effect. Helja exhibited stronger antifungal activity on the mutant strain, showing greater inhibition of fungal growth, loss of cell viability, morphological alteration, and formation of clusters with agglutinated cells. This differential biological activity of Helja was correlated with the biophysical parameters determined by solid phase assays and isothermal titration calorimetry, which demonstrated that the lectin established stronger interactions with the cell wall mannans of the mnn4∆ null mutant than with the WT strain. In conclusion, our results provide new evidence on the nature of the Helja molecular interactions with cell wall components, i.e. phosphomannan, and its impact on the antifungal activity. This study highlights the relevance of plant lectins in the design of effective antifungal therapies.

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Snake venoms are intricate mixtures of enzymes and bioactive factors that induce a range of detrimental effects in afflicted hosts. Certain Viperids, including Bothrops jararacussu, harbor C-type lectins (CTLs) known for their modulation of a variety of host cellular responses. In this study, we isolated and purified BjcuL, a CTL from B. jararacussu venom and investigated its impact on endothelial cell behavior, contrasting it with human galectin-1 (Gal-1), a prototype member of the galectin family with shared ß-galactoside-binding activity. We found that BjcuL binds to human dermal microvascular endothelial cells (HMECs) in a concentration- and carbohydrate-dependent fashion and reprograms the function of these cells, favoring a pro-inflammatory and pro-coagulant endothelial phenotype. In light of the quest for universal antagonists capable of mitigating the harmful consequences of snake venoms, BjcuL emerges as a promising target to be blocked in order to regulate pathological endothelial cell responses.

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Aim: Cryptococcus gattii causes a severe fungal infection with high mortality rate among immunosuppressed and immunocompetent individuals. Due to limitation of current antifungal treatment, new immunotherapeutic approaches are explored.Methods: This study investigated an immunization strategy utilizing heat-inactivated C. gattii with ArtinM as an adjuvant. C57BL/6 mice were intranasally immunized with heat-killed C. gattii and ArtinM was administrated either before immunization or along with HK-C. gattii. Mice were infected with C. gattii and the efficacy of the immunization protocol was evaluated.Results: Mice that received ArtinM exhibited increased levels of IL-10 and relative expression of IL-23 in the lungs, reduced fungal burden and preserved tissue integrity post-infection.Conclusion: Adjuvant ArtinM improved immunization against C. gattii infection in C57BL/6 mice.

Cryptococcus gattii is a fungus that can make lungs sick. Right now, there are no good treatments for it, so scientists are trying to find new ways to fight it. In a recent study, they tested a type of immunotherapy called ArtinM to see if it could help. When they gave ArtinM to mice, the mice got healthier and had less fungus in their lungs. This means ArtinM might be able to help fight this fungus.

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Multivalency in lectins plays a pivotal role in influencing glycan cross-linking, thereby affecting lectin functionality. This multivalency can be achieved through oligomerization, the presence of tandemly repeated carbohydrate recognition domains, or a combination of both. Unlike lectins that rely on multiple factors for the oligomerization of identical monomers, tandem-repeat lectins inherently possess multivalency, independent of this complex process. The repeat domains, although not identical, display slightly distinct specificities within a predetermined geometry, enhancing specificity, affinity, avidity and even oligomerization. Despite the recognition of this structural characteristic in recently discovered lectins by numerous studies, a unified criterion to define tandem-repeat lectins is still necessary. We suggest defining them multivalent lectins with intrachain tandem repeats corresponding to carbohydrate recognition domains, independent of oligomerization. This systematic review examines the folding and phyletic diversity of tandem-repeat lectins and refers to relevant literature. Our study categorizes all lectins with tandemly repeated carbohydrate recognition domains into nine distinct folding classes associated with specific biological functions. Our findings provide a comprehensive description and analysis of tandem-repeat lectins in terms of their functions and structural features. Our exploration of phyletic and functional diversity has revealed previously undocumented tandem-repeat lectins. We propose research directions aimed at enhancing our understanding of the origins of tandem-repeat lectin and fostering the development of medical and biotechnological applications, notably in the design of artificial sugars and neolectins.

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Diabetes mellitus (DM) is a chronic systemic disease characterized by a multifactorial nature, which may lead to several macro and microvascular complications. Diabetic retinopathy (DR) is one of the most severe microvascular complications of DM, which can result in permanent blindness. The mechanisms involved in the pathogenesis of DR are multiple and still poorly understood. Factors such as dysregulation of vascular regeneration, oxidative and hyperosmolar stress in addition to inflammatory processes have been associated with the pathogenesis of DR. Furthermore, compelling evidence shows that components of the immune system, including the complement system, play a relevant role in the development of the disease. Studies suggest that high concentrations of mannose-binding lectin (MBL), an essential component of the complement lectin pathway, may contribute to the development of DR in patients with DM. This review provides an update on the possible role of the complement system, specifically the lectin pathway, in the pathogenesis of DR and discusses the potential of MBL as a non-invasive biomarker for both, the presence and severity of DR, in addition to its potential as a therapeutic target for intervention strategies.

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Wheat germ agglutinin (WGA) demonstrates potential as an oral delivery agent owing to its selective binding to carbohydrates and its capacity to traverse biological membranes. In this study, we employed differential scanning calorimetry and molecular dynamics simulations to comprehensively characterize the thermal unfolding process of both the complete lectin and its four isolated domains. Furthermore, we present the nuclear magnetic resonance structures of three domains that were previously lacking experimental structures in their isolated forms. Our results provide a collective understanding of the energetic and structural factors governing the intricate unfolding mechanism of the complete agglutinin, shedding light on the specific role played by each domain in this process. The analysis revealed negligible interdomain cooperativity, highlighting instead significant coupling between dimer dissociation and the unfolding of the more labile domains. By comparing the dominant interactions, we rationalized the stability differences among the domains. Understanding the structural stability of WGA opens avenues for enhanced drug delivery strategies, underscoring its potential as a promising carrier throughout the gastrointestinal environment.

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Intelectins belong to a family of lectins with specific and transitory carbohydrate interaction capabilities. These interactions are related to the activity of agglutinating pathogens, as intelectins play a significant role in immunity. Despite the prominent immune defense function of intelectins, limited information about its structural characteristics and carbohydrate interaction properties is available. This study investigated an intelectin transcript identified in RNA-seq data obtained from the South American lungfish (Lepidosiren paradoxa), namely LpITLN2-B. The structural analyses predicted LpITLN2-B to be a homo-trimeric globular protein with the fibrinogen-like functional domain (FReD), exhibiting a molecular mass of 57 kDa. The quaternary structure is subdivided into three monomers, A, B, and C, and each domain comprises 11 ß-sheets: an anti-parallel ß-sheet, a ß-hairpin, and a disordered ß-sheet structure. Molecular docking demonstrates a significant interaction with disaccharides rather than monosaccharides. The preferential interaction with disaccharides highlights the potential interaction with pathogen molecules, such as LPS and Poly(I:C). The hemagglutination assay inhibited lectins activity, especially maltose and sucrose, highlighting lectin activity in L. paradoxa samples. Overall, our results show the potential relevance of LpITLN2-B in L. paradoxa immune defense against pathogens.

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Parasites possess remarkable abilities to evade and manipulate the immune response of their hosts. Echinococcus granulosus is a parasitic tapeworm that causes cystic echinococcosis in animals and humans. The hydatid fluid released by the parasite is known to contain various immunomodulatory components that manipulate host´s defense mechanism. In this study, we focused on understanding the effect of hydatid fluid on dendritic cells and its impact on autophagy induction and subsequent T cell responses. Initially, we observed a marked downregulation of two C-type lectin receptors in the cell membrane, CLEC9A and CD205 and an increase in lysosomal activity, suggesting an active cellular response to hydatid fluid. Subsequently, we visualized ultrastructural changes in stimulated dendritic cells, revealing the presence of macroautophagy, characterized by the formation of autophagosomes, phagophores, and phagolysosomes in the cell cytoplasm. To further elucidate the underlying molecular mechanisms involved in hydatid fluid-induced autophagy, we analyzed the expression of autophagy-related genes in stimulated dendritic cells. Our results demonstrated a significant upregulation of beclin-1, atg16l1 and atg12, indicating the induction of autophagy machinery in response to hydatid fluid exposure. Additionally, using confocal microscopy, we observed an accumulation of LC3 in dendritic cell autophagosomes, confirming the activation of this catabolic pathway associated with antigen presentation. Finally, to evaluate the functional consequences of hydatid fluid-induced autophagy in DCs, we evaluated cytokine transcription in the splenocytes. Remarkably, a robust polyfunctional T cell response, with inhibition of Th2 profile, is characterized by an increase in the expression of il-6, il-10, il-12, tnf-α, ifn-γ and tgf-ß genes. These findings suggest that hydatid fluid-induced autophagy in dendritic cells plays a crucial role in shaping the subsequent T cell responses, which is important for a better understanding of host-parasite interactions in cystic echinococcosis.

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BACKGROUND: The process of tissue injury in coronary artery disease (CAD) has been associated with activation of the complement system, partly due to the action of mannose-binding lectin (MBL) and C3, which are expressed in atherosclerotic lesions. OBJECTIVE: The aim of this study was to evaluate the serum levels of MBL and C3 in patients with CAD and to compare them with healthy controls. Additionally, we aim to assess the correlation between MBL and C3 levels and cardiometabolic parameters. METHODS: MBL and C3 serum concentration were determined by ELISA and immunoturbidimetry, respectively, in up to 119 patients undergoing coronary angiography for CAD evaluation, comprising 48 individuals diagnosed with acute myocardial infarction (MI) and 71 without MI. A total of 93 paired healthy controls were included in the study. RESULTS: Individuals with CAD had MBL serum concentration higher than controls (p = .002), regardless of the presence of MI (p = .006). In addition, high concentration of MBL (>2000 ng/mL) was more frequent in patients with CAD (p = .007; OR = 2.6; 95% CI = 1.3-5.1). C3 levels were not significantly associated with any of the patient groups but were positively correlated with cardiometabolic parameters such as body mass index (BMI) and triglycerides levels. CONCLUSIONS: Higher concentrations of MBL were found to be associated with CAD, whereas C3 levels were found to be associated with cardiovascular risk factors.

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Amoebiasis is a disease caused by Entamoeba histolytica, affecting the large intestine of humans and occasionally leading to extra-intestinal lesions. Entamoeba dispar is another amoeba species considered commensal, although it has been identified in patients presenting with dysenteric and nondysenteric colitis, as well as amoebic liver abscess. Amoebic virulence factors are essential for the invasion and development of lesions. There is evidence showing that the association of enterobacteria with trophozoites contributes to increased gene expression of amoebic virulence factors. Enteropathogenic Escherichia coli is an important bacterium causing diarrhea, with high incidence rates in the world population, allowing it to interact with Entamoeba sp. in the same host. In this context, this study aims to evaluate the influence of enteropathogenic Escherichia coli on ACFN and ADO Entamoeba dispar strains by quantifying the gene expression of virulence factors, including galactose/N-acetyl-D-galactosamine-binding lectin, cysteine proteinase 2, and amoebapores A and C. Additionally, the study assesses the progression and morphological aspect of amoebic liver abscess and the profile of inflammatory cells. Our results demonstrated that the interaction between EPEC and ACFN Entamoeba dispar strains was able to increase the gene expression of virulence factors, as well as the lesion area and the activity of the inflammatory infiltrate. However, the association with the ADO strain did not influence the gene expression of virulence factors. Together, our findings indicate that the interaction between EPEC, ACFN, and ADO Entamoeba dispar strains resulted in differences in vitro and in vivo gene expression of Gal/GalNAc-binding lectin and CP2, in enzymatic activities of MPO, NAG, and EPO, and consequently, in the ability to cause lesions.

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Mannose-binding lectin (MBL) binds to SARS-CoV-2, inhibits infection of susceptible cells, and activates the complement system via the lectin pathway. In this study, we investigated the association of MBL2 polymorphisms with the risk of hospitalization and clinical worsening in patients with COVID-19. A total of 550 patients with COVID-19 were included (94 non-hospitalized and 456 hospitalized). Polymorphisms in MBL2 exon 1 (codons 52, 54 and 57) and promoter region (-550, -221, and +4) were determined by real-time PCR. MBL and complement proteins were measured by Luminex. A higher frequency of the H/H genotype and the HYPA haplotype was observed in non-hospitalized patients when compared to hospitalized. In addition, critically ill patients carrying haplotypes associated with high MBL levels (HYPA/HYPA + HYPA/LYPA + HYPA/LYQA + LYPA/LYQA + LYPA/LYPA + LYQA/LYQA + LXPA/HYPA + LXPA/LYQA + LXPA/LYPA) were protected against lower oxygen saturation levels (P = 0.02), use of invasive ventilation use (P = 0.02, OR 0.38), and shock (P = 0.01, OR 0.40), independent of other potential confounders adjusted by multivariate analysis. Our results suggest that variants in MBL2 associated with high MBL levels may play a protective role in the clinical course of COVID-19.

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Pap smear screening is a widespread technique used to detect premalignant lesions of cervical cancer (CC); however, it lacks sensitivity, leading to identifying biomarkers that improve early diagnosis sensitivity. A characteristic of cancer is the aberrant sialylation that involves the abnormal expression of α2,6 sialic acid, a specific carbohydrate linked to glycoproteins and glycolipids on the cell surface, which has been reported in premalignant CC lesions. This work aimed to develop a method to differentiate CC cell lines and primary fibroblasts using a novel lectin-based biosensor to detect α2,6 sialic acid based on attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and chemometric. The biosensor was developed by conjugating gold nanoparticles (AuNPs) with 5 µg of Sambucus nigra (SNA) lectin as the biorecognition element. Sialic acid detection was associated with the signal amplification in the 1500-1350 cm-1 region observed by the surface-enhanced infrared absorption spectroscopy (SEIRA) effect from ATR-FTIR results. This region was further analyzed for the clustering of samples by applying principal component analysis (PCA) and confidence ellipses at a 95% interval. This work demonstrates the feasibility of employing SNA biosensors to discriminate between tumoral and non-tumoral cells, that have the potential for the early detection of premalignant lesions of CC.

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The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is a key vector of the phloem-limited bacteria Candidatus Liberibacter asiaticus (CLas) associated with huanglongbing (HLB), the most serious and currently incurable disease of citrus worldwide. Here we report the first investigation into the potential use of a spider venom-derived recombinant neurotoxin, ω/κ-HxTx-Hv1h (hereafter HxTx-Hv1h) when delivered alone or when fused to snowdrop lectin (Galanthus nivalis agglutinin; GNA) to control D. citri. Proteins, including GNA alone, were purified from fermented transformed yeast Pichia pastoris cultures. Recombinant HxTx-Hv1h, HxTx-Hv1h/GNA and GNA were all orally toxic to D. citri, with Day 5 median lethal concentrations (LC50) derived from dose-response artificial diet assays of 27, 20 and 52 µM, respectively. Western analysis of whole insect protein extracts confirmed that psyllid mortality was attributable to protein ingestion and that the fusion protein was stable to cleavage by D. citri proteases. When applied topically (either via droplet or spray) HxTx-Hv1h/GNA was the most effective of the proteins causing >70 % mortality 5 days post treatment, some 2 to 3-fold higher levels of mortality as compared to the toxin alone. By contrast, no significant mortality or phenotypic effects were observed for bumble bees (Bombus terrestris L.) fed on the recombinant proteins in acute toxicity assays. This suggests that HxTx-Hv1h/GNA has potential as a novel bioinsecticide for the management of D. citri offering both enhanced target specificity as compared to chemical pesticides and compatibility with integrated pest management (IPM) strategies.

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Lectins are proteins that reversibly bind to carbohydrates and are commonly found across many species. The Banana Lectin (BanLec) is a member of the Jacalin-related Lectins, heavily studied for its immunomodulatory, antiproliferative, and antiviral activity. In this study, a novel sequence was generated in silico considering the native BanLec amino acid sequence and 9 other lectins belonging to JRL. Based on multiple alignment of these proteins, 11 amino acids of the BanLec sequence were modified because of their potential for interference in active binding site properties resulting in a new lectin named recombinant BanLec-type Lectin (rBTL). rBTL was expressed in E. coli and was able to keep biological activity in hemagglutination assay (rat erythrocytes), maintaining similar structure with the native lectin. Antiproliferative activity was demonstrated on human melanoma lineage (A375), evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT). rBTL was able to inhibit cellular growth in a concentration-dependent manner, in an 8-h incubation, 12 µg/mL of rBTL led to a 28.94% of cell survival compared to cell control with 100%. Through a nonlinear fit out log-concentration versus biological response, an IC50% of 3.649 µg/mL of rBTL was determined. In conclusion, it is possible to state that the changes made to the rBTL sequence maintained the structure of the carbohydrate-binding site without changing specificity. The new lectin is biologically active, with an improved carbohydrate recognition spectrum compared to nBanLec, and can also be considered cytotoxic for A375 cells.

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Germline-encoded pattern recognition receptors, particularly C-type lectin receptors (CLRs), are essential for phagocytes to sense invading fungal cells. Among CLRs, Dectin-2 (encoded by Clec4n) plays a critical role in the antifungal immune response as it recognizes high-mannose polysaccharides on the fungal cell wall, triggering phagocyte functional activities and ultimately determining adaptive responses. Here, we assessed the role of Dectin-2 on the course of primary Paracoccidioides brasiliensis systemic infection in mice with Dectin-2-targeted deletion. Paracoccidioides brasiliensis constitutes the principal etiologic agent of paracoccidioidomycosis, the most prominent invasive mycosis in Latin American countries. The deficiency of Dectin-2 resulted in shortened survival rates, high lung fungal burden, and increased lung pathology in mice infected with P. brasiliensis. Consistently, dendritic cells (DCs) from mice lacking Dectin-2 infected ex vivo with P. brasiliensis showed impaired secretion of several proinflammatory and regulatory cytokines, including TNF-α, IL-1ß, IL-6, and IL-10. Additionally, when cocultured with splenic lymphocytes, DCs were less efficient in promoting a type 1 cytokine pattern secretion (i.e., IFN-γ). In macrophages, Dectin-2-mediated signaling was required to ensure phagocytosis and fungicidal activity associated with nitric oxide production. Overall, Dectin-2-mediated signaling is critical to promote host protection against P. brasiliensis infection, and its exploitation might lead to the development of new vaccines and immunotherapeutic approaches.

We report a critical role of the innate immune receptor Dectin-2 during Paracoccidioides brasiliensis infection. Fungal sensing by Dectin-2 improved the survival of mice and lowered fungal burden. Further, Dectin-2 was required for cytokine production, phagocytosis, and fungal killing by phagocytes.

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Cells use glycans to encode information that modulates processes ranging from cell-cell recognition to programmed cell death. This information is encoded within a glycocode, and its decoding is performed by carbohydrate-binding proteins. Among these, lectins stand out due to their specific and reversible interaction with carbohydrates. Changes in glycosylation patterns are observed in several pathologies, including cancer, where abnormal glycans are found on the surfaces of affected tissues. Given the importance of the bioprospection of promising biomolecules, the current work aimed to determine the structural properties and anticancer potential of the mannose-specific lectin from seeds of Canavalia villosa (Cvill). Experimental elucidation of the primary and 3D structures of the lectin, along with glycan array and molecular docking, facilitated the determination of its fine carbohydrate-binding specificity. These structural insights, coupled with the lectin's specificity, have been combined to explain the antiproliferative effect of Cvill against cancer cell lines. This effect is dependent on the carbohydrate-binding activity of Cvill and its uptake in the cells, with concomitant activation of autophagic and apoptotic pathways.

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OBJECTIVES: The present study investigated the anti-depressive-like (anti-immobility) effect of a lectin from Moringa oleifera seeds (WSMoL) in mice. METHODS: To evaluate an acute effect, the animals were treated with WSMoL (1, 2, and 4 mg/kg, i.p.) 30 min before the tail suspension test (TST). To investigate the involvement of monoaminergic and nitrergic signaling, the mice were pre-treated with selective antagonists. The role of the WSMoL carbohydrate-recognizing domain (CRD) was verified using previous blockage with casein (0.5 mg/mL). The subacute anti-immobility effect was also evaluated by administering WSMoL (1, 2, and 4 mg/kg, i.p.) once a day for 7 d. Finally, an open field test (OFT) was performed to identify possible interferences of WSMoL on animal locomotory behavior. RESULTS: WSMoL reduced the immobility time of mice in the TST at all doses, and combined treatment with fluoxetine (5 mg/kg, i.p.) and WSMoL (1 mg/kg) was also effective. The CRD appeared to be involved in the anti-immobility effect since the solution of WSMoL (4 mg/kg) pre-incubated with casein showed no activity. The lectin effect was prevented by the pre-treatment of mice with ketanserin, yohimbine, and SCH 23390, thereby demonstrating the involvement of monoaminergic pathways. In contrast, pre-treatment with L-NAME, aminoguanidine, and L-arginine did not interfere with lectin action. WSMoL exhibited a subacute effect in the TST, thereby reducing immobility time and increasing agitation time even on the seventh day. OFT data revealed that the anti-immobility effect was not caused by interference with locomotor behavior. CONCLUSION: WSMoL elicits an anti-depressant-like effect that is dependent on monoaminergic signaling.

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There is increasing pressure for innovative methods to treat compromised and difficult-to-heal wounds. Consequently, new strategies are needed for faster healing, reducing infection, hydrating the wound, stimulating healing mechanisms, accelerating wound closure, and reducing scar formation. In this scenario, lectins present as good candidates for healing agents. Lectins are a structurally heterogeneous group of glycosylated or non-glycosylated proteins of non-immune origin, which can recognize at least one specific monosaccharide or oligosaccharide specific for the reversible binding site. Cell surfaces are rich in glycoproteins (glycosidic receptors) that potentially interact with lectins through the number of carbohydrates reached. This lectin-cell interaction is the molecular basis for triggering various changes in biological organisms, including healing mechanisms. In this context, this review aimed to (i) provide a comprehensive overview of relevant research on the potential of vegetable lectins for wound healing and tissue regeneration processes and (ii) discuss future perspectives.

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WSMoL, a water-soluble lectin from the seeds of Moringa oleifera, present several biological activities. This work aimed to evaluated the toxicity and antitumor activity of WSMoL. To analyze toxicity, it was determined hematological, biochemical and histological parameters; consumption of water and feed as well as the weight of the animals. Antitumor analysis included evaluation of tumor weight, histology and cytokine levels. Acute toxicity assay revealed 60% mortality of animals treated with lectin at 200 mg/kg i. p. At 100 mg/kg i. p., the animals showed a decreased food and water consumption as well weight gain in comparison with control. However, no animal died and there were no alterations in blood parameters or histological analysis. Antitumor activity evaluated at safe doses (2.5, 5 and 10 mg/kg) showed a significant reduction in tumor weight. Tumor photomicrographs evidenced that WSMoL treatment reduced dissemination of tumor cells. WSMoL (5 and 10 mg/kg) significantly enhance the immune function in the tumor environment as showed by increased the levels of pro-inflammatory (TNF-α, IFN-γ, IL-2, IL-6, and IL-17) and anti-inflammatory (IL-4 and IL-10) cytokines. In conclusion, WSMoL showed in vivo antitumor activity in mice bearing sarcoma 180 tumor, probably by increase the immune response against the tumor.

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PURPOSE: The treatment of leishmaniasis, an anthropozoonosis caused by Leishmania protozoa, is limited by factors, such as adverse effects, toxicity, and excessive cost, which has highlighted the importance of novel drugs. In this context, natural products have been considered as sources of antileishmanial agents. This study investigated the leishmanicidal activity of Microgramma vacciniifolia frond lectin (MvFL) on promastigotes and amastigotes of Leishmania amazonensis. METHODS: The effects of MvFL on promastigote proliferation and macrophage infection by amastigotes were evaluated and mean inhibitory concentrations (IC50) were calculated. As a safety assessment, the hemolytic capacity of MvFL (6.25-200 µg/mL) against mouse and human erythrocytes was determined. Additionally, the ability of MvFL (6.25-100 µg/mL) to modulate lysosomal and phagocytic activities and the nitric oxide (NO) production by murine peritoneal macrophages was also investigated. RESULTS: After 24 h, MvFL inhibited the proliferation of L. amazonensis promastigotes, with an IC50 of 88 µg/mL; however, hemolytic activity was not observed. MvFL also reduced macrophage infection by amastigotes with an IC50 of 52 µg/mL. Furthermore, treatment with MvFL reduced the number of amastigotes internalized by infected murine peritoneal macrophages by up to 68.9% within 48 h. At a concentration of 25 µg/mL, MvFL stimulated lysosomal activity of macrophages within 72 h, but did not alter phagocytic activity or induce NO production at any of the tested concentrations. CONCLUSION: MvFL exerts antileishmanial activity and further studies are needed to assess its therapeutic potential in in vivo experimental models of leishmaniasis.

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