FioSchisto's expert perspective on implementing WHO guidelines for schistosomiasis control and transmission elimination in Brazil.

The World Health Organization (WHO) recognizes schistosomiasis as one of the Neglected Tropical Diseases targeted for global elimination in the 2030 Agenda of the Sustainable Development Goals. In Brazil, schistosomiasis mansoni is considered a public health problem, particularly prevalent among vulnerable populations living in areas with poor environmental and sanitary conditions. In 2022, the WHO published a Guideline encompassing recommendations to assist national programs in endemic countries in achieving morbidity control, eliminating schistosomiasis as a public health problem, and advancing towards interrupting transmission. The perspectives presented here, collectively prepared by members of the Oswaldo Cruz Foundation's (Fiocruz) Schistosomiasis Translational Program (FioSchisto), along with invited experts, examine the feasibility of the WHO recommendations for the Brazilian settings, providing appropriate recommendations for public health policies applicable to the epidemiological reality of Brazil, and suggests future research to address relevant issues. In Brazil, the provision of safe water and sanitation should be the key action to achieve schistosomiasis elimination goals. The agencies involved in measures implementation should act together with the Primary Care teams for planning, executing, monitoring, and evaluating actions in priority municipalities based on their epidemiological indicators. Host snails control should prioritize judicious ecological interventions at breeding sites. The Information, Education, and Communication (IEC) strategy should be associated with water and sanitation and other control actions, actively involving school community. To identify infected carriers, FioSchisto recommends a two-stage approach of immunological and molecular tests to verify transmission interruption during the intervention and beyond. Praziquantel administration should be done under medical supervision at the Primary Care level. MDA should be considered in exceptional settings, as a measure of initial attack strategy in locations presenting high endemicity, always integrated with water and sanitation, IEC, and snail control. To assist decision-making, as well as the monitoring and evaluation of strategic actions, there is a need for an Information System. FioSchisto considers this systematization essential to make investments in strategic research to support the improvement of schistosomiasis control actions. Efforts toward schistosomiasis elimination in Brazil will succeed with a paradigm shift from the vertical prescriptive framework to a community-centered approach involving intersectoral and interdisciplinary collaboration.

Docking-Based Virtual Screening Enables Prioritizing Protein Kinase Inhibitors With In Vitro Phenotypic Activity Against Schistosoma mansoni.

Schistosomiasis is a parasitic neglected disease with praziquantel (PZQ) utilized as the main drug for treatment, despite its low effectiveness against early stages of the worm. To aid in the search for new drugs to tackle schistosomiasis, computer-aided drug design has been proved a helpful tool to enhance the search and initial identification of schistosomicidal compounds, allowing fast and cost-efficient progress in drug discovery. The combination of high-throughput in silico data followed by in vitro phenotypic screening assays allows the assessment of a vast library of compounds with the potential to inhibit a single or even several biological targets in a more time- and cost-saving manner. Here, we describe the molecular docking for in silico screening of predicted homology models of five protein kinases (JNK, p38, ERK1, ERK2, and FES) of Schistosoma mansoni against approximately 85,000 molecules from the Managed Chemical Compounds Collection (MCCC) of the University of Nottingham (UK). We selected 169 molecules predicted to bind to SmERK1, SmERK2, SmFES, SmJNK, and/or Smp38 for in vitro screening assays using schistosomula and adult worms. In total, 89 (52.6%) molecules were considered active in at least one of the assays. This approach shows a much higher efficiency when compared to using only traditional high-throughput in vitro screening assays, where initial positive hits are retrieved from testing thousands of molecules. Additionally, when we focused on compound promiscuity over selectivity, we were able to efficiently detect active compounds that are predicted to target all kinases at the same time. This approach reinforces the concept of polypharmacology aiming for "one drug-multiple targets". Moreover, at least 17 active compounds presented satisfactory drug-like properties score when compared to PZQ, which allows for optimization before further in vivo screening assays. In conclusion, our data support the use of computer-aided drug design methodologies in conjunction with high-throughput screening approach.

Schistosoma mansoni FES Tyrosine Kinase Involvement in the Mammalian Schistosomiasis Outcome and Miracidia Infection Capability in Biomphalaria glabrata.

Schistosomiasis is a neglected tropical disease (NTD) caused by helminthes from the Schistosoma genus. This NTD can cause systemic symptoms induced by the deposition of parasite eggs in the host liver, promoting severe complications. Functional studies to increase knowledge about parasite biology are required for the identification of new drug targets, because the treatment is solely based on praziquantel administration, a drug in which the mechanism of action is still unknown. Protein kinases are important for cellular adaptation and maintenance of many organisms homeostasis and, thus, are considered good drug targets for many pathologies. Accordingly, those proteins are also important for Schistosoma mansoni, as the parasite relies on specific environmental signals to develop into its different stages. However, the specific roles of protein kinases in S. mansoni biology are not well understood. This work aims at investigating the tyrosine-protein kinase FES (Feline Sarcoma) functions in the maintenance of S. mansoni life cycle, especially in the establishment of mammalian and invertebrate hosts' infection. In this regard, the verification of Smfes expression among S. mansoni stages showed that Smfes is more expressed in infective free-living stages: miracidia and cercariae. Schistosomula exposed to SmFES-dsRNA in vitro presented a reduction in movement and size and increased mortality. Mice infected with Smfes-knocked-down schistosomula exhibited a striking reduction in the area of liver granuloma and an increased rate of immature eggs in the intestine. Female adult worms recovered from mice presented a reduced size and changes in the ovary and vitellarium; and males exhibited damage in the gynecophoral canal. Subsequently, miracidia hatched from eggs exposed to SmFES-dsRNA presented changes in its capability to infect and to sense the snail mucus. In addition, the SmFES RNAi effect was stable from miracidia to cercariae. The establishment of infection with those cercariae reproduced the same alterations observed for the knocked-down schistosomula infection. Our findings show that SmFES tyrosine kinase (1) is important in schistosomula development and survival; (2) has a role in adult worms pairing and, consequently, female maturation; (3) might be essential for egg antigen expression, thus responsible for inducing granuloma formation and immunomodulation; and (4) is essential for miracidia infection capability. In addition, this is the first time that a gene is kept knocked down during three different S. mansoni life stages and that a tyrosine kinase is implicated in the parasite reproduction and infection establishment in the mammalian host. Accordingly, SmFES should be explored as an alternative to support schistosomiasis treatment and morbidity control.

Estudo funcional da proteína quinase JNK de Schistosoma mansoniatravés de expressão heteróloga no organismo modelo Caenorhabditis elegans / Functional studies of the protein kinase JNK Schistosoma mansoni by heterologous expression in the model organism C. elegans

A identificação e caracterização dos mecanismos e moléculas envolvidos em sinalização celular são essenciais para o entendimento da biologia parasitária do S. mansoni. Proteína quinases desempenham papel chave em vias de sinalização e tem sido propostas como potenciais alvos para o desenvolvimento de novas drogas anti-Schistosoma. Visto que a caracterização funcional em S. mansoni é dificultada por limitações nos métodos de transformação genética deste parasito, o presente estudo propõe o uso de C. elegans como um modelo para a expressão heteróloga de genes de S. mansoni que codificam proteínas quinases. Genes que codificam proteína quinase sem S. mansoni,homólogos aos identificados em C. elegans, foram selecionados pelo nosso grupo a partir do proteoma do parasito através de uma abordagem filogenômica. Inicialmente, foi selecionada a proteína quinase JNK, que participa da via de sinalização das MAP quinases para a realização das análises experimentais. Em C. elegans, a proteína JNK está relacionada ao aumento de longevidade e da resistência aos estresses térmico e oxidativo. Oligonucleotídeos específicos foram desenhados paraamplificar a região promotora do gene emC. elegansbem como as regiões codificantes(CDS) em ambos os organismos. A região promotora foi amplificada a partir do DNAgenômico extraído deC. elegansadultos. O RNA total foi extraído de esquistossômuloseC. elegansadultos. As CDS foram amplificadas a partir do cDNA sintetizado e osfragmentos de DNA resultantes foram clonados emE. coliDH5α. As construçõesobtidas foram digeridas com enzimas de restrição selecionadas de forma a linearizar ovetor contendo a região promotora e recuperar as CDS. Posteriormente, foramrealizadas subclonagens através da ligação das CDS deC. eleganseS. mansonicom aconstrução contendo a região promotora.C. elegansN2 receberam as construçõesfinais através de microinjeção. Foram obtidas três linhagens que expressam Ce_JNK-1,denominadas N2Ex01[Ce_jnk-1], N2Ex02[Ce_jnk-1]e N2Ex03[Ce_jnk-1]e duaslinhagens expressando Sm_JNK, denominadas N2Ex04[Sm_jnk]e N2Ex05[Sm_jnk].Os níveis de expressão de Sm_JNK e Ce_JNK-1 nas linhagens transgênicas foramavaliados por RT-PCR quantitativo. Apesar do aumento da expressão de JNKobservado nas linhagens transgênicas, não houve aumento na longevidade dasmesmas. Embora esta seja a primeira utilização de expressão heteróloga emC. eleganspara investigar a função de genes deS. mansoni, esta técnica tem sido utilizada comsucesso para nematóides parasitos e pode tornar-se uma abordagem alternativa para osestudos funcionais em outros parasitos.

Estudo funcional da proteína quinase JNK de Schistosoma mansoniatravés de expressão heteróloga no organismo modelo Caenorhabditis elegans

A identificação e caracterização dos mecanismos e moléculas envolvidos em sinalização celular são essenciais para o entendimento da biologia parasitária do S. mansoni. Proteína quinases desempenham papel chave em vias de sinalização e tem sido propostas como potenciais alvos para o desenvolvimento de novas drogas anti-Schistosoma. Visto que a caracterização funcional em S. mansoni é dificultada por limitações nos métodos de transformação genética deste parasito, o presente estudo propõe o uso de C. elegans como um modelo para a expressão heteróloga de genes de S. mansoni que codificam proteínas quinases. Genes que codificam proteína quinase sem S. mansoni,homólogos aos identificados em C. elegans, foram selecionados pelo nosso grupo a partir do proteoma do parasito através de uma abordagem filogenômica. Inicialmente, foi selecionada a proteína quinase JNK, que participa da via de sinalização das MAP quinases para a realização das análises experimentais. Em C. elegans, a proteína JNK está relacionada ao aumento de longevidade e da resistência aos estresses térmico e oxidativo.

Oligonucleotídeos específicos foram desenhados paraamplificar a região promotora do gene emC. elegansbem como as regiões codificantes(CDS) em ambos os organismos. A região promotora foi amplificada a partir do DNAgenômico extraído deC. elegansadultos. O RNA total foi extraído de esquistossômuloseC. elegansadultos. As CDS foram amplificadas a partir do cDNA sintetizado e osfragmentos de DNA resultantes foram clonados emE. coliDH5α. As construçõesobtidas foram digeridas com enzimas de restrição selecionadas de forma a linearizar ovetor contendo a região promotora e recuperar as CDS. Posteriormente, foramrealizadas subclonagens através da ligação das CDS deC. eleganseS. mansonicom aconstrução contendo a região promotora.C. elegansN2 receberam as construçõesfinais através de microinjeção. Foram obtidas três linhagens que expressam Ce_JNK-1,denominadas N2Ex01[Ce_jnk-1], N2Ex02[Ce_jnk-1]e N2Ex03[Ce_jnk-1]e duaslinhagens expressando Sm_JNK, denominadas N2Ex04[Sm_jnk]e N2Ex05[Sm_jnk].Os níveis de expressão de Sm_JNK e Ce_JNK-1 nas linhagens transgênicas foramavaliados por RT-PCR quantitativo. Apesar do aumento da expressão de JNKobservado nas linhagens transgênicas, não houve aumento na longevidade dasmesmas. Embora esta seja a primeira utilização de expressão heteróloga emC. eleganspara investigar a função de genes deS. mansoni, esta técnica tem sido utilizada comsucesso para nematóides parasitos e pode tornar-se uma abordagem alternativa para osestudos funcionais em outros parasitos