Instituto Butantan

Background Streptococcus pneumoniae (pneumococcus) is a common cause of respiratory and invasive infections in humans. PCV13, a pneumococcal conjugate vaccine used globally, is highly effective against diseases caused by pneumococcal serotypes included in its formulation. However, one of them, the serotype 3 (ST3) is still being relatively commonly isolated from patients, suggesting an escape from vaccine‐induced immunity. The thick capsule produced by ST3 facilitates bacterial evasion from the immune system. Additionally, host immune responses may influence the outcome of ST3 infection. Here we evaluated the influence of inflammation in the adaptive immune responses and protection induced by PCV13 against ST3, using two outbred mice lines that were phenotypically selected for high (AIRmax) and low (AIRmin) inflammatory responses. Methods AIRmin and AIRmax mice were immunized with PCV13. Inbred BALB/c mice were used as reference for vaccine efficacy. Induction of IgG against polysaccharides (PS) from pneumococcal serotype 1 (ST1) and ST3 were evaluated by ELISA. Protection was tested against invasive infections with ST1 and ST3 pneumococcal strains. Sera were compared by IgG binding to pneumococcal surface, induction of pneumococcal agglutination and opsonophagocytosis. The phagocytic capacity of mice‐derived neutrophils was also evaluated. Results Immunization of AIRmin, AIRmax and BALB/c mice with PCV13 induced IgG against PS from ST1 and ST3 pneumococci. Despite vaccination, AIRmin mice were not protected against fatal infection with ST3. Sera from AIRmin mice immunized with PCV13 presented lower levels of anti‐PS3 IgG, with reduced capacity to bind to pneumococcal surface. Reduced capacity to induce opsonophagocytosis of ST3 pneumococci in vitro was also observed. Conversely, PCV13 protected AIRmin mice against fatal infection with ST1 and this correlated with the capacity of the sera to induce ST1 opsonophagocytosis. Conclusions Our results show that both host and bacterial features can influence the outcome of protection induced by PCV13 against ST3 pneumococcal infection.

A series of novel derivatives of Poliacetylene Glycosides (PAGs) were synthesized, and their antiproliferative and antiviral properties were evaluated. Starting from D-(+)-glucose pentaacetate as a precursor, a commercially available and...

There are more than 200 species of Macronyssidae parasitizing reptiles, birds, and mammals worldwide. While most species are found on wild animals, show some degree of geographic, and host group specificity, Ophionyssus natricis thrives on captive snakes and lizards and as a result of the pet trade, has a cosmopolitan distribution. In this study, we are providing new host records for this species for the state of São Paulo, as well as SEM images and the first partial sequences of Brazilian specimens.

Background Despite decades of research, an effective schistosomiasis vaccine remains elusive. The radiation-attenuated (RA) cercarial vaccine remains the best model for eliciting high levels of protection. We have recently explored this model in mice to identify potentially protective pathways by examining gene expression patterns in peripheral blood mononuclear cells (PBMC). Methods Herein, we reanalyzed the transcriptomic data from PBMC obtained from vaccinated and infected C57BL/6 mice in three timepoints (Days 7 and 17 after infection or vaccination and Day 7 post-challenge). In addition, we generated new data on PBMC collected 35 days after infection. Deconvolution analysis was performed to estimate immune cell composition by CIBERSORTx. Gene co-expression networks and over-representation analysis (ORA) were performed using the CEMiTool package. Protein-protein interaction networks were constructed using STRING, and the hub proteins for each module were identified using Cytoscape. Results Co-expression network analysis identified a module (M2) associated with the infection process, grouping genes related to a Th2 immune response, and a second module (M6) associated with the vaccination process, displaying pathways related to a Th1 response, CD8 + T cells and NK cells. Within each module, five hub proteins were identified based on protein-protein interaction networks. The M2 infection module revealed Chil3, Il4, Cx3cr1, Emr1 and Ccl2 as hubs, while module M6, associated with vaccination, disclosed Prf1, Klrc1, IFN-γ, Ncr1 and Tbx21 as hub proteins. Conclusions Our data point to the potentiald role of NK cells that may contribute to the RA vaccine response through the production of IFN-γ orchestrated by the T-bet transcription factor (Tbx21). Graphical Abstract

Babesia spp. and Theileria spp. are tick-borne apicomplexan protozoa that can cause disease in animals and humans. Deer are considered reservoirs for a wide variety of Piroplasmida species, including some potentially zoonotic. This study aimed to investigate the occurrence and genetic diversity of piroplasmids in wild deer sampled in four Brazilian states (São Paulo, Mato Grosso do Sul, Paraná and Goiás). For this purpose, extracted DNA samples from 181 deer buffy coat samples (138 Blastocerus dichotomus, 26 Subulo gouazoubira, 4 Mazama jucunda, 3 Mazama rufa and 10 Ozotocerus bezoarticus) were subjected to a nested PCR (nPCR) assay based on the 18S rRNA gene in order to perform a screening for piroplasmids and characterized based on the near-complete 18S rRNA, hsp70 and cox-3 genes. As a result, 75.14% (136/181) samples were positive for piroplasmids. Of these, 108 (79.41%), 101 (74.26%) and 67 (49.26%) were positive to near complete 18S rRNA, hsp70 and cox-3 genes, respectively. Phylogenetic analyses based on three molecular markers showed similar topology to each other. All sequences obtained in the present study were positioned into the Theileria sensu stricto clade, forming a distinct clade, albeit close to T. cervi. Most sequences grouped together into a large clade divided into subclades, which were often related to deer genus/species, showing that Theileria lineages seemed to show specificity according to deer genus/species. Two 18S rRNA sequences (one obtained from S. gouazoubira and another from M. jucunda) were positioned into a different clade, apart from other sequences detected in this study, indicating that different species of Theileria occur in deer from Brazil. Two subclusters were observed in the phylogenetic analysis based on the hsp70 gene: the first containing only sequences detected in marsh deer and the second grouping sequences detected in brocket deer (Mazama spp. and S. gouazoubira). The latter was also divided into smaller clades that grouped Theileria genotypes according to deer species (M. jucunda, M. rufa and S. gouazoubira). This study provides the first molecular evidence of Theileria infection in M. jucunda, as well as co-infection by distinct Theileria (sub)species/genotypes in the same deer was evidenced. Finally, this study expanded the knowledge on the diversity of Theileria spp. infecting deer from South America.

Voltage-gated potassium channels play a crucial role in cellular repolarization and are potential therapeutic targets in neuroinflammatory disorders and neurodegenerative diseases. This study explores Tityus bahiensis scorpion venom for neuroactive peptides. We identified the αKtx12 peptide as a potent neuroprotective agent. In SH-SY5Y cells, αKtx12 significantly enhances viability, validating its pharmacological potential. And in the animal model, we elucidate central nervous system (CNS) mechanism of αKtx12 through neuroproteomic analyses highlighting αKtx12 as a valuable tool for characterizing neuroplasticity and neurotropism, revealing its ability to elicit more physiological responses. The peptide’s potential to promote cell proliferation and neuroprotection suggests a role in functional recovery from nervous system injury or disease. This research unveils the neuroactive potential of scorpion venom-derived αKtx12’s, offering insights into its pharmacological utility. The peptide’s impact on neuronal processes suggests a promising avenue for therapeutic development, particularly in neurodegenerative conditions.

Introduction Complement activation split products are signatures of many immunopathological disorders. Among the laboratory findings observed in these diseases, a reduction in the level of circulating intact complement components can be mentioned, and this change has also been detected in envenomation by multiple Africanized honeybee (Apis mellifera) stings. Although envenomation by these animals elicits diverse life-threatening reactions, the capacity of bee venom (AmV) to activate the human complement system remains elusive. Methods and findings By coupling immunochemical and functional approaches, it was observed that AmV strongly consumes components of the alternative pathway (AP) of the complement system in normal human serum (NHS). Additionally, AmV interfered with classical (CP) and lectin pathways (LP) activities. In parallel, a high increase in Ba fragment levels was detected, suggesting that the changes in AP activity were due to its activation. Furthermore, an increase in the level of the C1s-C1INH complex and a decrease in the physiological level of MASP1-C1INH suggested that CP and LP were also activated in the presence of AmV. Strikingly, NHS exposed to increasing AmV concentrations varying from 5 to 1000 µg/mL presented a high generation of C3a, C4a and C5a anaphylatoxins, and sC5b-9 complexes assembly, thus reinforcing that AmV triggers complement activation. Conclusion These results show that AmV is a strong complement activator. This activation presents a mixed profile, with a predominance of AP activation. This suggests that complement split products can play important roles in the envenomation by Africanized honeybee, as they could induce diverse immunopathological events observed in patients and may also dictate patient clinical prognosis.

Background/Objectives: Tuberculosis continues to be a significant global health concern, causing 1.3 million deaths in 2022, particularly affecting children under 5 years old. The Bacillus Calmette-Guérin (BCG) vaccine, developed in 1921, remains the primary defense against tuberculosis but requires modernized production methods. The recombinant BCG-pertussis strain shows potential in providing dual protection against tuberculosis and whooping cough, especially for vulnerable newborns, and enhanced efficacy against bladder cancer. Implementing submerged cultivation techniques for rBCG-pertussis production can offer increased productivity and standardization. Methods: This study explores a fed-batch cultivation strategy with pH-stat control to feed L-glutamic acid through the acid pump into 1 L bioreactor. Three pH values were evaluated for fed-batch and a simple batch without pH control was done for comparison. The viable cell concentration was compared before and after freeze-drying samples harvested during the cultures. Results: L-glutamic acid was identified as the preferred substrate for rBCG-pertussis. While the fed-batch strategy did not enhance the maximum specific growth rate compared to simple batch cultivation, it did improve the specific growth rate after day 4 in the pH 7.4-controlled fed-batch cultures, thereby reducing the cultivation time. Fed-batch cultures controlled at three pH levels exhibited lower optical density than the simple batch, although the viable cell counts were similar. Notably, samples harvested after day 8 from the simple batch cultures showed a reduction in CFU/mL after freeze-drying, whereas all fed-batch samples exhibited high recovery of viable cell counts post lyophilization. Conclusions: The additional glutamate supplied to the fed-batch cultures may have protected the cells during the lyophilization process.

Cinobufagin (CB), a bufadienolide, has shown promising potential as an anticancer agent, particularly in combating lung cancer. This systematic review synthesizes preclinical evidence on CB’s effects against lung cancer, focusing on its mechanisms of action, efficacy, and potential clinical implications. We analyzed data from various preclinical studies involving both in vitro cell line models and in vivo animal models. The reviewed studies indicate that CB effectively reduces cell viability, induces apoptosis, and inhibits cell proliferation, migration, and invasion across multiple lung cancer cell lines and xenograft models. Specifically, CB was found to decrease cell viability and increase apoptosis in lung cancer cells by modulating key molecular pathways, including Bcl-2, Bax, cleaved caspases, caveolin-1, FLOT2, Akt, STAT3, and FOXO1. In vivo studies further demonstrated significant inhibition of tumor growth with minimal toxicity. However, limitations include reliance on in vitro models, which may not fully represent in vivo tumor dynamics, and a lack of long-term safety data. The studies also vary in their methodologies and cell line models, which may not accurately encompass all lung cancer subtypes or predict human responses. Despite these limitations, CB’s ability to target specific molecular pathways and its promising results in preclinical models suggest it could be a valuable addition to lung cancer treatment strategies. Our review suggests further clinical trials to validate its efficacy and safety in humans. Future research should explore combination therapies and optimize delivery methods to enhance clinical outcomes.

An annotated checklist and taxonomic review of the spiders of Saint Helena is presented. A total of 88 genera and 114 species are known; of these, 12 genera and 45 species are endemic. Two new genera and two new species are described: Anapistula martinae Sherwood, Harvey, Fowler, Joshua, Stevens, Scipio O’Dean & Ellick sp. nov., Helenidion Sherwood, Marusik, Fowler, Stevens & Joshua gen. nov., Ischnothyreus christyjoae Sherwood, Henrard, Peters, Stevens & Fowler sp. nov., and Trust Sherwood, Marusik, Wilkins, P. Ashmole & M. Ashmole gen. nov. Three new combinations are proposed: Helenidion sciaphilum (Benoit, 1977) comb. nov. (type species), Helenidion huberti (Benoit, 1977) comb. nov., and Zelotes funereus (Dalmas, 1921) comb. nov. Lepthyphantes albimaculatus (O. Pickard-Cambridge, 1873) (Linyphiidae) is synonymized with Lepthyphantes leprosus (Ohlert, 1865) syn. nov. Lynxosa Roewer, 1960 gen. rest. is restored to house the lycosids L. inexorabilis (O. Pickard-Cambridge, 1870) comb. rest., L. ligata (O. Pickard-Cambridge, 1870) comb. rest., L. nefasta (Tongiorgi, 1977) comb. nov., and L. veseyensis (Sherwood, Henrard, Logunov & Fowler, 2023) comb. nov. The previously undescribed sexes of Benoitodes sanctaehelenae (Strand, 1909) (Gnaphosidae), Hahnia laticeps Simon, 1898 (Hahniidae), Helenactyna crucifera (O. Pickard-Cambridge, 1873) (Dictynidae, first known male for the genus), Paraheliophanus napoleon Clark & Benoit, 1977 (Salticidae), and Trust solium (Benoit, 1977) comb. nov. (Theridiidae) are described. Bonapruncinia sanctaehelenae Benoit, 1977, originally described from juveniles, is supplemented with a first description of the adult female. Lectotypes and paralectotypes are designated for the salticid species Paraheliophanus subinstructus (O. Pickard-Cambridge, 1873) and Pellenes inexcultus (O. Pickard-Cambridge, 1873). Seven species are newly recorded from the island: Clubiona hitchinsi Saaristo, 2002 (Clubionidae), Latrodectus renivulvatus Dahl, 1902 (Theridiidae), Micropholcus fauroti (Simon, 1887) (Pholcidae), Oecobius marathaus Tikader, 1962 (Oecobiidae), Steatoda nobilis (Thorell, 1875) (Theridiidae), Theridion melanostictum O. Pickard-Cambridge, 1876 (Theridiidae), and Theridion proximum Lawrence, 1964 (Theridiidae). Epigynal duplication, a rare anomaly in spiders, is reported for the prodidomid Zimirina relegata Cooke, 1977.

Previous in vitro works focusing on virulence determinants of the spirochete Leptospira implicated metalloproteinases as putative contributing factors to the pathogenicity of these bacteria. Those proteins have the capacity to degrade extracellular matrix components (ECM) and proteins of host's innate immunity, notably effectors of the complement system. In this study, we gained further knowledge on the role of leptolysin, one of the leptospiral‐secreted metalloproteinases, previously described as having a broad substrate specificity. We demonstrated that a proportion of human patients with mild leptospirosis evaluated in the current study produced antibodies that recognize leptolysin, thus indicating that the protease is expressed during host infection. Using recombinant protein and a knockout mutant strain, Manilae leptolysin⁻, we determined that leptolysin contributes to Leptospira interrogans serum resistance in vitro, likely by proteolysis of complement molecules of the alternative, the classical, the lectin, and the terminal pathways. Furthermore, in a hamster model of infection, the mutant strain retained virulence; however, infected animals had lower bacterial loads in their kidneys. Further studies are necessary to better understand the role and potential redundancy of metalloproteinases on the pathogenicity of this important neglected disease.

Background SARS-CoV-2 variants have distinct features of transmissibility, infectivity, and aggressiveness that may cause different clinical manifestations. A better understanding of the disease presentation and progression could help to outline more precise preventive and treatment frameworks. This study describes the differences in COVID-19 presentation and outcomes across five variant waves. Methods This prospective cohort was conducted in Serrana, São Paulo State, Brazil. Clinical and demographic data was obtained from June 2020 to December 2022 as part of an enhanced health surveillance system for COVID-19, based on increasing access to diagnostic testing for SARS-CoV-2 and patient follow-up. Individuals were assessed for COVID-19 symptoms and comorbidities. Mild cases were followed up for at least 14 days, and severe cases until discharge or death. Samples were genetically sequenced, and variant waves were determined based on global SARS-CoV-2 variant predominance (>90 % sequenced samples), being as follows: Ancestral, Delta, Gamma, Omicron BA.1, and Omicron BA.2 waves. The relationship between clinical data and disease outcomes was analyzed in each variant wave. Results Patients infected during the Delta wave were the youngest (36.1 ± 18.2 years, p < 0.001). The proportion of female patients was higher across all waves. Positivity rate, disease severity, and COVID-19-related deaths varied among them. Ageusia and anosmia were related to SARS-CoV-2 positivity during the Ancestral, Gamma, and Delta waves but not in Omicron BA.1 and Omicron BA.2 waves. Diarrhea presented a lower chance of positivity only in Omicron BA.1 and Omicron BA.2. Dyspnea was the most consistent risk factor for severity across all waves. Conclusions Although patients with COVID-19 from different SARS-CoV-2 variants shared some clinical-epidemiological characteristics, each variant presented distinguishable features related to positivity and severity. This could help to understand the dynamics of COVID-19 variants and update recommendations for clinical practice.

Habitat selection by spiders is strongly influenced by biotic factors such as the availability and diversity of prey and abiotic factors such as temperature, humidity, and the structural complexity of the habitat. Structural complexity is an aspect that intensely affects species persistence, population stability, and the coexistence of interacting species. Trees comprise a complex set of microhabitats due to their large biomass and heterogeneity of the architectural components of their trunk surface and branches. Spider species that live on trunks have diversified physiological or morphological adaptations that confer advantages in this environment. In this study, we experimentally examined the habitat choice by the tree-dwelling spiders Selenops cocheleti (Selenopidae), Corinna rubripes (Corinnidae), and Loxosceles gaucho (Sicariidae). We found that microhabitat specialization was restricted to trunk architectural characteristics rather than plant taxonomy. Selenops cocheleti and C. rubripes significantly preferred loose barks and holes in the trunks, respectively, showing that both spider species can evaluate the physical structure of the microhabitat on a fine scale. On the other hand, L. gaucho selected crevices and holes near the base of the trunk without giving much importance to the physical characteristics of the microhabitat per se (e.g., depth, height, length). Our findings indicate that for generalist predators like spiders, coexistence relies heavily on spatial segregation driven by distinct habitat preferences, irrespective of their method for capturing prey.

Introduction Leptospirosis is a global zoonosis that affects more than one million people per year, with a lethality rate of approximately 15%. Chemokines are crucial in the immune response against Leptospira, recruiting leukocytes to the site of infection and regulating immune activity. In previous studies, we have shown that CCL2, CXCL5, and CCL8 are involved in the leptospirosis process, although the mechanisms are not understood. Methods In this study, we present the frequency of Leptospira serovars in human samples. We then evaluated the profile of various chemokines in sera from patients diagnosed with leptospirosis, assessing the possible correlation between them. Moreover, we evaluated the changes in the chemokine profile on different days after the first symptoms. The frequency of the Leptospira serovars in human samples is presented. Results and discussion The main findings were that CCL5, CXCL5, and CXCL9 are highly expressed during leptospirosis, indicating a special role of these molecules in the immunity and pathogenesis of the disease. The correlation analysis of detected chemokines CXCL11, CXCL9, CCL3, and CCL2 helps to clarify the role of each cytokine in leptospirosis. The possible use of CCL5 as a biomarker for complementary diagnosis of the disease is suggested.

This comprehensive review explores the cutting-edge advancements in snake venom research, focusing on the integration of proteomics, genomics, transcriptomics, and bioinformatics. Highlighting the transformative impact of these technologies, the review delves into the genetic and ecological factors driving venom evolution, the complex molecular composition of venoms, and the regulatory mechanisms underlying toxin production. The application of synthetic biology and multi-omics approaches, collectively known as venomics, has revolutionized the field, providing deeper insights into venom function and its therapeutic potential. Despite significant progress, challenges such as the functional characterization of toxins and the development of cost-effective antivenoms remain. This review also discusses the future directions of venom research, emphasizing the need for interdisciplinary collaborations and new technologies (mRNAs, cryo-electron microscopy for structural determinations of toxin complexes, synthetic biology, and other technologies) to fully harness the biomedical potential of venoms and toxins from snakes and other animals.

Purpose α-Lapachona (aLAP) and β-lapachona (bLAP) are noteworthy anticancer naphthoquinones. The chemoresistance observed in bladder cancer represents a global health concern, with relation to mutations in the TP53 gene and alterations in the expression of long non-coding RNA (lncRNAs). This study evaluated the effects of aLAP and bLAP on bladder tumor cell lines with different TP53 statuses. Methods Cytotoxicity was assessed using the MTT reduction method and cell migration by scratch assay while clonogenic survival and cell cycle were evaluated through cell colony counting and flow cytometry, respectively. The expression of lncRNAs ( JHDM1D-AS1 , SBF2-AS1 , CDT-2132N18.2 , and RP11-363E7.4 ) and the JHDM1D gene was evaluated through RT-qPCR. Results bLAP demonstrated greater cytotoxicity than aLAP. Its inhibitory effects on clonogenic survival, migration, and the cell cycle were observed in all cell lines and were related to the modulation of lncRNAs expression. A reduction in lncRNA SBF2-AS1 and JHDM1D gene expression was observed in RT4 cells, accompanied by an increase in lncRNA RP11-363E7.4 . Conversely, in the cells with mutated TP53 (J82), a reduction in JHDM1D-AS1 and JHDM1D was observed. Conclusion The antiproliferative effects of bLAP in bladder cancer cells are independent of TP53 statuses, yet occur through a distinct action mechanism, with variations in lncRNAs expression.

Study of substances with potentially neuroprotective has been one of the research focus on drugs development. Toxic proteins of Lonomia obliqua caterpillars, which have caused several accidents in southern Brazil, were identified in the hemolymph with anti-apoptotic activity. This study aims the evaluation of the protein profile and the hemolymph effect on cell viability of rats’ primary cultured hippocampal neurons after apoptosis induction. Semi-quantitative shotgun proteomics approach was used to evaluate the protein profile of 3 caterpillars lots of different origin. Were identified a total of 76 proteins, 71 in hemolymph and 40 in fractions. Antiviral protein predominated in crude hemolymph, following by serine proteases, hemolins and protease inhibitors. In fractions were identified hemolins, serine proteases and protease inhibitors. The treatment of rats’ primary cultured hippocampal neurons with the chromatographic fraction at concentration of 0.05 and 0.10% (v/v) for 24 hours, with subsequently apoptosis induction was able to maintain cell viability significantly higher than positive control. Hemolymph protein composition can show qualitative and quantitative variations intra species when compared different origins animals and consequently exposed to various environmental factors. The results shown on this study may contribute to the identification of proteins with potential use as neuroprotective in degenerative conditions.