The Zebrafish Breathes new Life into the Study of Tuberculosis

Tuberculosis (TB) is a global health emergency. Up to one-third of the world’s population is infected with Mycobacterium tuberculosis, and the pathogen continues to kill 1.5 million people annually. Currently, the means for preventing, diagnosing, and treating TB are unsatisfactory. One of the main reasons for the poor progress in TB research has been a lack of good animal models to study the latency, dormancy, and reactivation of the disease. Although sophisticated in vitro and in silico methods suitable for TB research are constantly being developed, they cannot reproduce the complete vertebrate immune system and its interplay with pathogens and vaccines. However, the zebrafish has recently emerged as a useful alternative to more traditional models, such as mice, rabbits, guinea pigs, and non-human primates, for studying the complex pathophysiology of a mycobacterial infection. The model is based on the similarity between Mycobacterium marinum – a natural fish pathogen – and M. tuberculosis. In both zebrafish larvae and adult fish, an infection with M. marinum leads to the formation of macrophage aggregates and granulomas, which resemble the M. tuberculosis infections in humans. In this review, we will summarize the current status of the zebrafish model in TB research and highlight the advantages of using zebrafish to dissect mycobacterial virulence strategies as well as the host immune responses elicited against them. In addition, we will discuss the possibilities of using the adult zebrafish model for studying latency, dormancy, and reactivation in a mycobacterial infection

Functional Characterization of the Infection-Inducible Peptide Edin in Drosophila melanogaster

Drosophila is a well-established model organism for studying innate immunity because of its high resistance against microbial infections and lack of adaptive immunity. In addition, the immune signaling cascades found in Drosophila are evolutionarily conserved. Upon infection, activation of the immune signaling pathways, Toll and Imd, leads to the expression of multiple immune response genes, such as the antimicrobial peptides (AMPs). Previously, we identified an uncharacterized gene edin among the genes, which were strongly induced upon stimulation with Escherichia coli in Drosophila S2 cells. Edin has been associated with resistance against Listeria monocytogenes, but its role in Drosophila immunity remains elusive. In this study, we examined the role of Edin in the immune response of Drosophila both in vitro and in vivo. We report that edin expression is dependent on the Imd-pathway NF-κB transcription factor Relish and that it is expressed upon infection both in vitro and in vivo. Edin encodes a pro-protein, which is further processed in S2 cells. In our experiments, Edin did not bind microbes, nor did it possess antimicrobial activity to tested microbial strains in vitro or in vivo. Furthermore, edin RNAi did not significantly affect the expression of AMPs in vitro or in vivo. However, edin RNAi flies showed modestly impaired resistance to E. faecalis infection. We conclude that Edin has no potent antimicrobial properties but it appears to be important for E. faecalis infection via an uncharacterized mechanism. Further studies are still required to elucidate the exact role of Edin in the Drosophila immune response

Turvetyöryhmän loppuraportti

Pääministeri Sanna Marinin hallitusohjelman mukaan turpeen energiakäyttö tulee vähintään puolittaa vuoteen 2030 mennessä ja muutoksen tulee tapahtua alueellisesti ja sosiaalisesti oikeudenmukaisella tavalla sähkön ja lämmön toimitus- ja huoltovarmuutta vaarantamatta. Työ- ja elinkeinoministeriö asetti kansallisen laaja-alaisen turvetyöryhmän 31.3.2020 valmistelemaan toimenpide-ehdotuksia em. tavoitteiden mukaisesti. Raportissa kuvataan turvealan nykytila ja arvioidut kehityssuunnat. Työryhmä katsoo, että suurimmat haasteet liittyvät turveyrittäjien tilanteen parantamiseen ja huolto- ja toimitusvarmuuden turvaamiseen, sillä turpeen energiakäyttö vähenee paljon aiempaa ennakoitua nopeammin. Nämä esitykset koostuvat turveliiketoiminnan lopettaville yrittäjille suunnatusta luopumispaketista sekä tuista turveyrittäjien siirtymiselle uuteen yritystoimintaan. Huoltovarmuuden osalta ehdotetuilla toimenpiteillä pyritään säilyttämään energiaturpeen tuotantovalmius ns. siirtymäkauden aikana. Raportti sisältää myös muita toimenpide-ehdotuksia esimerkiksi kasvu- ja kuiviketurpeen tuotannon turvaamisesta sekä turvesoiden jälkikäytöstä. Turvetyöryhmällä ei ole ollut mahdollisuutta arvioida ehdotusten valtiontukivaikutuksia. Valtiontukiin sekä JTF-rahastoon liittyviä kysymyksiä on selvitettävä poliittisessa jatkovalmistelussa

beta carbonic anhydrase is required for female fertility in Drosophila melanogaster

Background: Carbonic anhydrases (CAs, EC 4.2.1.1) are ubiquitous enzymes that catalyze the reversible hydration reaction of carbon dioxide. CAs are present as six structurally divergent enzyme families: alpha, beta, gamma, delta, zeta and eta. beta-CAs have a wide distribution across different species including invertebrates. Previously, we showed that Drosophila melanogaster beta-CA is a highly active mitochondrial enzyme. In this study, we investigated the function of Drosophila beta-CA by silencing the expression of the beta-CA gene using UAS/GAL4-based RNA interference (RNAi) in Drosophila in vivo. Results: Crossing beta-CA RNAi lines over ubiquitous Actin driver flies did not produce any viable progeny, indicating that beta-CA expression is required for fly development. RNAi silencing of beta-CA ubiquitously in adult flies did not affect their survival rate or function of mitochondrial electron transport chain. Importantly, beta-CA RNAi led to impaired reproduction. All beta-CA knockdown females were sterile, and produced few or no eggs. Whole ovaries of knockdown females looked normal but upon cadherin staining, there was an apparent functional defect in migration of border cells, which are considered essential for normal fertilization. Conclusions: These results indicate that although Drosophila beta-CA is dispensable for survival of adult flies, it is essential for female fertility.Peer reviewe

Elevated human placental heat shock protein 5 is associated with spontaneous preterm birth

Background: Specific heat shock proteins are associated with pregnancy complications, including spontaneous preterm birth (SPTB). Placental proteomics and whole exome sequencing recently suggested an association between heat shock protein HSPA5 and uncomplicated SPTB. In the present study, we investigated the localization of and possible roles for HSPA5 in SPTB. Methods: Western blot was performed to validate the result from the previously published proteomic analysis. We used qPCR to assess mRNA expression of genes and immunohistochemistry and immunoelectron microscopy to examine localization of HSPA5 in placental tissue. We silenced the HSPA5 gene in the HTR8/SVneo human trophoblast cell line to investigate possible functions of HSPA5. Results: HSPA5 was upregulated in placentas from SPTBs compared to spontaneous term births. We did not observe upregulation of HSPA5 mRNA in placental samples. The protein was localized in placental trophoblast in both spontaneous preterm and term placentas. Gene silencing of HSPA5 in human trophoblast cell culture affected the inflammatory response and decreased the expression of several proinflammatory genes. Conclusions: We suggest that upregulation of HSPA5 in the placenta is associated with spontaneous preterm labor. HSPA5 may promote the inflammatory response and alter the anti-inflammatory state of the placenta which could eventually lead to premature labor. Impact: We validated upregulation of HSPA5 in placentas from spontaneous preterm birth. HSPA5 was not upregulated at transcriptional level which suggests that it may be regulated post-translationally.Silencing HSPA5 in a human trophoblast–derived cell line suggested that HSPA5 promotes expression of proinflammatory cytokines. The emerging inflammation could lead to spontaneous preterm labor.Identifying inflammatory pathways and factors associated with spontaneous preterm birth increases knowledge of the molecular mechanisms of premature labor. This could provide cues to predict imminent premature labor and lead to information about how to safely maintain pregnancies.publishedVersionPeer reviewe

Identification of novel antigen candidates for a tuberculosis vaccine in the adult zebrafish (Danio rerio)

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