Host Organism Research Articles

Wolbachia in Antarctic terrestrial invertebrates: Absent or undiscovered?

AbstractInteractions between a host organism and its associated microbiota, including symbiotic bacteria, play a crucial role in host adaptation to changing environmental conditions. Antarctica provides a unique environment for the establishment and maintenance of symbiotic relationships. One of the most extensively studied symbiotic bacteria in invertebrates is Wolbachia pipientis, which is associated with a wide variety of invertebrates. Wolbachia is known for manipulating host reproduction and having obligate or facultative mutualistic relationships with various hosts. However, there is a lack of clear understanding of the prevalence of Wolbachia in terrestrial invertebrates in Antarctica. We present the outcomes of a literature search for information on the occurrence of Wolbachia in each of the major taxonomic groups of terrestrial invertebrates (Acari, Collembola, Diptera, Rotifera, Nematoda, Tardigrada). We also performed profiling of prokaryotes based on three marker genes and Kraken2 in available whole genome sequence data obtained from Antarctic invertebrate samples. We found no reports or molecular evidence of Wolbachia in these invertebrate groups in Antarctica. We discuss possible reasons underlying this apparent absence and suggest opportunities for more targeted future research to confirm bacteria's presence or absence.

Changes of immune function mediated by Gasdermin-E in the immune microenvironment of primary oral squamous cell carcinoma

In primary oral squamous cell carcinoma (OSCC), the tumor microenvironment (TME) constitutes a highly intricate ecosystem comprised of cellular and acellular elements. The tumor immune microenvironment (TIME) is characterized by the presence of a broad of immune cells, while there is a scarcity of cytotoxic lymphocytes (CTLs) intratumorally. Consequently, the recruitment of a larger cohort of CTLs to infiltrate the tumor core has emerged as a pressing scientific challenge. Gasdermin E (GSDME), as a pivotal effector protein in pyroptosis, plays a significant role in anti-tumor therapy. Here, primary OSCC was induced by Gsdme knockout (KO) mice and wild type (WT) mice of the same strain respectively, using the chemical mutagen 4-Nitroquinoline N-oxide (4-NQO). Through comparative analysis of immune function between the two kinds of mice, intriguing observations have been elucidated, the presence of GSDME was instrumental in augmenting the infiltration of lymphocytes towards the neoplastic site, effectively ameliorating the TIME. Our findings elucidated that the absence of GSDME promotes the development of primary OSCC, accompanied by a notable increase in malignancy. Furthermore, our data delineated a positive inter-relationship between the presence of GSDME and the host organism’s immunological reactivity, which enhances the TIME in primary OSCC.

A supramolecular approach towards the photorelease of encapsulated caged acids in water: 7-diethylaminothio-4-coumarinyl molecules as triggers.

Herein, we establish the release of aliphatic acids in water upon excitation of 7-diethylaminothio-4-coumarinyl derivatives encapsulated within the organic host octa acid (OA). The 7-diethylaminothio-4-coumarinyl skeleton, employed here as the trigger, photoreleases caged molecules from the excited triplet state, in contrast to its carbonyl analogue, where the same reaction is known to occur from the excited singlet state. Encapsulation in OA solubilizes molecules in water that are otherwise water-insoluble, and retains the used trigger within itself following the release of the aliphatic acid. Such supramolecular characteristics usher in new features to the photorelease methodology. The thiocarbonyl chromophore extends the absorption of coumarinyl trigger to visible range while enhancing the intersystem crossing (ISC) to the triplet state, making it the reactive state. Despite the non-polar environment within the OA capsules the photocleavage occurs in a heterolytic fashion to release the conjugate base and the used trigger as triplet carbocation in an adiabatic process. Interestingly, the triplet carbocation crosses to the ground singlet surface (closed shell singlet carbocation) with the help of water molecules, possibly aided by C = S chromophore. Utilizing the known excited state dynamics of related thiocoumarinyl and coumarinyl systems, we have identified a few of the important mechanistic features of the photorelease process of 7-diethylaminothio-4-coumarinyl derivatives. Ultrafast excited state dynamic studies and quantum chemical calculations planned should help us better understand the photorelease process so as to effectively exploit the proposed system for potential applications.

Novel PCR assay for the identification of two transmissible cancers in Cerastoderma edule

Transmissible cancers are a rare phenomenon in which cancer cells are passed between individuals, leading to the development of neoplasia in the host organism. Transmissible cancers have been identified in three independent clonal lineages in mammals and eight different clonal lineages in bivalves. This study focused on the development of a multiplex PCR assay for the detection of two types of bivalve transmissible neoplasias (BTN) of cockles Cerastoderma edule (CedBTN1 and CedBTN2). The diagnostic sensitivity (Se) and specificity (Sp) of the new PCR of hemolymph samples were assessed using a maximum likelihood estimation in the 88 samples compared to diagnoses obtained by histology and confirmed with genomic analyses. The results showed a Se of 100 % and a Sp of 98.1 % for CedBTN1, and a Se and Sp of 100 % for CedBTN2. The analytical Sp and Se were tested using DNA extractions from infected and non-infected C. edule and other bivalves affected by BTN. The assay demonstrated high analytical sensitivity and specificity, detecting down to 0.4 % of circulating CedBTN1 cells at a DNA concentration of 0.05 ng/µL in a hemolymph sample of a cockle with 85.7 % of CedBTN1 cells. The multiplex PCR assay was type-specific for CedBTN and capable of detecting both lineages simultaneously.Overall, this multiplex PCR assay is a reliable tool for the detection of transmissible cancers in cockles which will facilitate the diagnosis and monitoring of the disease

The metabolic profiles of phenolic acids and aromatic amino acids in the Orobanche crenata parasite and its host faba bean at different infestation stages

Orobanche crenata is a root holoparasite that depends on its host for nutritional requirements. The shikimate pathway that metabolizes about 30% of the assimilated carbon in photosynthetic plants plays a role in host-parasite relationships. Aromatic amino acids (AAAs) and phenolic acids are derived from the shikimate pathway and serve as precursors of a wide number of primary and secondary metabolites. The effects of the O. crenata parasite on the phenolic acid and AAA profiles of two faba bean varieties and the differences of these compounds between the host organs and attached parasite at infestation stages were studied. Hosts and attached parasites were collected and divided, depending on the stage of parasite development, into four stages. The results revealed that phenolic acids and free AAAs tended to increase in parasitized roots compared to those of healthy roots, and the greatest increase in phenolic contents occurred at the first infestation stage. Syringic acid was observed to be unique to the parasite. Profiles of phenolic acids and AAAs were changed during the developmental stages of the parasite and differed from those of its host. Caffeic in the parasite reached more than 100 times that in Nubaria 4 host roots at the fourth infestation stage. Free phenylalanine in the parasite ranged between 2.2 and 5.5 times its level in host roots at all infestation stages. This study provides much evidence that indicates O. crenata is able to self-regulate its phenolic and AAA metabolites during its developmental stages, which differ from those of its host.

Intra-specific variations in Schistosoma mansoni and their possible contribution to inconsistent virulence and diverse clinical outcomes.

Schistosoma mansoni was introduced from Africa to the Americas during the transatlantic slave trade and remains a major public health problem in parts of South America and the Caribbean. This study presents a comprehensive comparative analysis of three S. mansoni strains with different geographical origins-from Liberia, Belo Horizonte and Puerto Rico. We demonstrated significant variation in virulence and host-parasite interactions. We investigated the phenotypic characteristics of the parasite and its eggs, as well as the immunopathologic effects on laboratory mouse organ systems. Our results show significant differences in worm morphology, worm burden, egg size, and pathologic organ changes between these strains. The Puerto Rican strain showed the highest virulence, as evidenced by marked liver and spleen changes and advanced liver fibrosis indicated by increased collagen content. In contrast, the strains from Liberia and Belo Horizonte had a less pathogenic profile with less liver fibrosis. We found further variations in granuloma formation, cytokine expression and T-cell dynamics, indicating different immune responses. Our study emphasizes the importance of considering intra-specific variations of S. mansoni for the development of targeted therapies and public health strategies. The different virulence patterns, host immune responses and organ pathologies observed in these strains provide important insights for future research and could inform region-specific interventions for schistosomiasis control.

Establishment of Animal Infection Model of Spirometra Mansoni and Identification of Spirometra Mansoni by Enzyme-Linked Immunosorbent Assay.

Objective: Spirometra mansoni is a crucial zoonotic parasite. Its larvae are more harmful than adult worms due to their ability to migrate through the host's tissues and organs. Therefore, it is necessary to establish an animal model of spargana for observing pathological changes and exploring diagnostic techniques. Methods: In this study, we infected Kunming mice and cats without any pathogens by feeding sparganum (with the scolex and neck) in order to understand the infection cycle of S. mansoni and explore the preservation host of sparganosis. The infection of S. mansoni was determined by fecal detection and enzyme-linked immunosorbent assay (ELISA). Results: In the model of cats, the eggs of S. mansoni were found in the feces ten days after the infection. The serum-specific IgG antibodies against S. mansoni were positive in experimental groups (mice and cats), and after sixty days, the S. mansoni worms isolated from experimental groups were collected. Conclusion: In conclusion, the experimental results show that mice and cats can be stably infected with S. mansoni through feeding sparganum (with the scolex and neck). The infection method of this study has the potential to establish a practical model for investigating the diagnostic process of S. mansoni, laying the groundwork for application and development. ELISA was used to diagnose mice and cats infected with sparganosis mansoni, providing a case for non-invasive identification of animal sparganosis.

Interacting Emission Species among Donor and Acceptor Moieties in a Donor-Grafted Polymer Host/TADF-Guest System and Their Effects on Photoluminescence and Electroluminescence.

Thermally activated delayed fluorescence (TADF)-based electroluminescence (EL) devices adopting a host/guest strategy in their emitting layer (EML) are capable of realizing high efficiency. However, TADF emitters composed of donor and acceptor moieties as guests dispersed in organic host materials containing a donor and/or an acceptor are subject to donor-acceptor (D-A) interactions. In addition, electron delocalization between neighboring emitter molecules could form different species of aggregates. Here, we investigate the effects of intermolecular interacting emission species on the optoelectronic properties of sky-blue/green/red (sB/G/R) TADF emitters as guests using poly(biphenyl-Si/Ge) grafted with various donor moieties as hosts. We found the presence of guest/guest exciplex (Dg/Ag)*, host/guest exciplexes (Dh/Ag)*, and aggregates through the exploration of interactions between neighboring TADF guest molecules and between host and TADF-guest molecules. The nonradiative 3(Dh/Ag)* (ΔEST ≈ 0.5 eV) could increase the internal conversion rate (kIC) and reduce delayed luminescence, and both of them could cause a decrease in PLQY. The luminescence of 3(Dh/Ag)* may have a positive or negative effect on PLQY depending on its triplet energy. As the singlet and triplet energies of (aggregate)* are lower than those of (ICT)*, energy transfer from (ICT)* to (aggregate)* could occur. The low PLQY nature of (aggregate)* means that it is more likely to cause quenching in device emission. The emissions from (Dh/Ag)* and (aggregate)* are found to have increased full width at half-maximum and lead to lower emission color purity. Such intermolecular interactions should also occur in host/guest (TADF) systems and nondoped TADF emitter systems and thus are important factors for the molecular design of the TADF emitter and/or its accompanying host for high device efficiency and emission color purity.

DENV and ZIKV infection: Species specificity and broad cell tropism

Nearly one-third of countries worldwide have reported cases of Dengue virus (DENV) and Zika virus (ZIKV) infections, highlighting the significant threat these viruses pose to global public health. As members of the Flavivirus genus within the Flaviviridae family, DENV and ZIKV have demonstrated the ability to infect a wide range of cell lines from multiple species in vitro. However, the range of susceptible animal models is notably limited, and field studies indicate that their capacity to infect host organisms is highly restricted, with a very narrow range of target cells in vivo. The virus's ability to hijack host cellular machinery plays a crucial role in determining its cellular and species specificity. In this review, we examine how DENV and ZIKV exploit host cells to facilitate their replication, offering new insights that could inform the development of antiviral drugs and therapeutic targets.

Successful formation of sperm cells from transplanted primordial germ cells in sterile interspecific avian recipients.

Primordial germ cells (PGCs) are stem cells, from which only gametes develop. In birds, the female sex is heterogametic, thus female gene conservation necessitates preservation of PGCs. PGC transplantation can generate germline chimeras in a host organism and develop into gametes. However, competition between host and transplanted PGCs hinder efficiency of germline chimera generation. We hypothezised that in sterile hybrid recipients with no germ cells of its own, transplanted donor PGCs may exclusively form gametes. Advantages of sterile hybrids as host for PGCs is compliant with many national regulations on genetically modified organisms and technically simpler procedure than the use of busulphan. Therefore, we investigated whether sterile interspecific hybrids may be suitable as recipients for supporting donor PGCs by injecting green fluorescent protein-labelled chicken PGCs into 3-day-old Guinea fowl and domestic fowl hybrid embryos and monitoring PGC development. The injected PGCs colonized almost 100% of the recipient gonads and produced mature spermatozoa after 44 weeks. However, gamete production in these hybrids was initiated much slower than in domestic fowls. This delay may be caused by suboptimal hormonal regulation of gametogenesis in the hybrids. Our results suggest that sterile interspecific hybrids may be suitable hosts for PGCs for efficient gamete production.

Coexisting bacterial aminoacyl-tRNA synthetase paralogs exhibit distinct phylogenetic backgrounds and functional compatibility with Escherichia coli.

Aminoacyl-tRNA synthetases (aaRSs) are universally essential enzymes that synthesize aminoacyl-tRNA substrates for protein synthesis. Although most organisms require a single aaRS gene for each proteinogenic amino acid to translate their genetic information, numerous species encode multiple gene copies of an aaRS. Growing evidence indicates that organisms acquire extra aaRS genes to sustain or adapt to their unique lifestyle. However, predicting and defining the function of repeated aaRS genes remains challenging due to their potentially unique physiological role in the host organism and the inconsistent annotation of repeated aaRS genes in the literature. Here, we carried out comparative, phylogenetic, and functional studies to determine the activity of coexisting paralogs of tryptophanyl-, tyrosyl-, seryl-, and prolyl-tRNA synthetases encoded in several human pathogenic bacteria. Our analyses revealed that, with a few exceptions, repeated aaRSs involve paralogous genes with distinct phylogenetic backgrounds. Using a collection of Escherichia coli strains that enabled the facile characterization of aaRS activity in vivo, we found that, in almost all cases, one aaRS displayed transfer RNA (tRNA) aminoacylation activity, whereas the other was not compatible with E. coli. Together, this work illustrates the challenges of identifying, classifying, and predicting the function of aaRS paralogs and highlights the complexity of aaRS evolution. Moreover, these results provide new insights into the potential role of aaRS paralogs in the biology of several human pathogens and foundational knowledge for the investigation of the physiological role of repeated aaRS paralogs across bacteria.

Retraction: Differential Effects of VEGFR-1 and VEGFR-2 Inhibition on Tumor Metastases Based on Host Organ Environment.

Retraction: Differential Effects of VEGFR-1 and VEGFR-2 Inhibition on Tumor Metastases Based on Host Organ Environment.

Current development and trends of cancer immunotherapy

Normally, Tumor cells are able to evade the body's immune system and stifle it using a variety of tactics, which enables them to endure through every phase of the immunological reaction against the tumor. This is because the immune system is capable of identifying and eliminating tumor cells within the tumor microenvironment. This article describes current and future trends in cancer treatment and cancer immunotherapy, as well as the specific processes that occur in the cancer immune cycle. A class of disorders known as cancer is distinguished by aberrant cell division and invasion potential. Cancer immunotherapy has shown immense potential and possibilities in recent years, and its research has grown increasingly focused due to advancements in science and technology. The host organism's immune system generates anticancer defences during tumour development through various progressive and combinatorial mechanisms hence the term cancer-immunity cycle. The aim of this article is to describe the basic process of the cancer immune cycle as well as the various immunotherapies that are commonly used in the clinical setting today, as well as trends and future prospects. This review discusses adoptive cell transfer, cytokine therapy, cancer vaccinations, oncolytic viral treatments, and immune checkpoint inhibitors.

Genomic insights into Verticillium: a review of progress in the genomics era.

Genomics has emerged as a great tool in enhancing our understanding of the biology of Verticillium species and their interactions with the host plants. Through different genomic approaches, researchers have gained insights into genes, pathways and virulence factors that play crucial roles in both Verticillium pathogenesis and the defense responses of their host organisms. This review emphasizes the significance of genomics in uncovering the mechanisms that underlie pathogenicity, virulence, and host resistance in Verticillium fungi. Our goal is to summarize recent discoveries in Verticillium research highlighting progress made in comprehending the biology and interactions of Verticillium fungi. The integration of genomics into Verticillium studies has the potential to open avenues for developing strategies to control diseases and produce crop varieties resistant to verticillium, thereby offering sustainable solutions for enhancing agricultural productivity.

Cancer-induced systemic pre-conditioning of distant organs: building a niche for metastatic cells.

From their early genesis, tumour cells integrate with the surrounding normal cells to form an abnormal structure that is tightly integrated with the host organism via blood and lymphatic vessels and even neural associations. Using these connections, emerging cancers send a plethora of mediators that efficiently perturb the entire organism and induce changes in distant tissues. These perturbations serendipitously favour early metastatic establishment by promoting a more favourable tissue environment (niche) that supports the persistence of disseminated tumour cells within a foreign tissue. Because the establishment of early metastatic niches represents a key limiting step for metastasis, the creation of a more suitable pre-conditioned tissue strongly enhances metastatic success. In this Review, we provide an updated view of the mechanisms and mediators of primary tumours described so far that induce a pro-metastatic conditioning of distant organs, which favours early metastatic niche formation. We reflect on the nature of cancer-induced systemic conditioning, considering that non-cancer-dependent perturbations of tissue homeostasis are also able to trigger pro-metastatic conditioning. We argue that a more holistic view of the processes catalysing metastatic progression is needed to identify preventive or therapeutic opportunities.

Visible Light-Responsive Crystalline B←N Host Adducts with Solvent-Induced Allosteric Effect for Guest Release.

Photo-responsive organic crystals, capable of converting light energy into chemical energy to initiate conformational transitions, present an emerging strategy for developing lightweight and versatile smart materials. However, visible light-triggered tailored guests capture and release behaviors in all-organic solids are rarely reported. Here, we introduce a photoreactive crystalline boron-nitrogen (B←N) host adduct with the ability to undergo [2+2] photocycloaddition upon 447 nm light exposure. This process facilitates single-crystal-to-single-crystal (SCSC) photodimerization in the mother liquor, maintaining the original B←N host structure. Weakened intermolecular interactions within the photodimer host contribute to fast guest release in air under irradiation. Furthermore, the dynamic B←N bonds enable reversible transformations between organic host adducts and adduct cocrystals under the solvent-induced allosteric effect. As a result, four B←N host adduct crystals containing individual alkane guest are easily obtained and exhibited the ability of photo-controlled alkane release. Therefore, the integration of photo reactivity and structural transformation within B←N host adduct enables customized capture and release of guest molecules.

Visible Light‐Responsive Crystalline B←N Host Adducts with Solvent‐Induced Allosteric Effect for Guest Release

AbstractPhoto‐responsive organic crystals, capable of converting light energy into chemical energy to initiate conformational transitions, present an emerging strategy for developing lightweight and versatile smart materials. However, visible light‐triggered tailored guests capture and release behaviors in all‐organic solids are rarely reported. Here, we introduce a photoreactive crystalline boron‐nitrogen (B←N) host adduct with the ability to undergo [2+2] photocycloaddition upon 447 nm light exposure. This process facilitates single‐crystal‐to‐single‐crystal (SCSC) photodimerization in the mother liquor, maintaining the original B←N host structure. Weakened intermolecular interactions within the photodimer host contribute to fast guest release in air under irradiation. Furthermore, the dynamic B←N bonds enable reversible transformations between organic host adducts and adduct cocrystals under the solvent‐induced allosteric effect. As a result, four B←N host adduct crystals containing individual alkane guest are easily obtained and exhibited the ability of photo‐controlled alkane release. Therefore, the integration of photo reactivity and structural transformation within B←N host adduct enables customized capture and release of guest molecules.

Landscape of evolutionary arms races between transposable elements and KRAB-ZFP family

Transposable elements (TEs) are mobile parasitic sequences that have expanded within the host genome. It has been hypothesized that host organisms have expanded the Krüppel-associated box-containing zinc finger proteins (KRAB-ZFPs), which epigenetically suppress TEs, to counteract disorderly TE transpositions. This process is referred to as the evolutionary arms race. However, the extent to which this evolutionary arms race occurred across various TE families remains unclear. In the present study, we systematically explored the evolutionary arms race between TE families and human KRAB-ZFPs using public ChIP-seq data. We discovered and characterized new instances of evolutionary arms races with KRAB-ZFPs in endogenous retroviruses. Furthermore, we found that the regulatory landscape shaped by this arms race contributed to the gene regulatory networks. In summary, our results provide insight into the impact of the evolutionary arms race on TE families, the KRAB-ZFP family, and host gene regulatory networks.

Whole-Transcriptome Analysis Reveals Potential CeRNA Regulatory Mechanism in Takifugu rubripes against Cryptocaryon irritans Infection.

Cryptocaryon irritans (C. irritans) is a proto-ciliate parasite that infects marine fishes, including the cultured species Takifugu rubripes (T. rubripes), causing disease and potential mortality. In host organisms, infection by parasites triggers an immune response that is modulated by regulatory elements including proteins and non-coding RNAs. In this study, the whole transcriptome RNA sequencing of T. rubripes gill tissue before and after infection with C. irritans was performed to reveal the competitive endogenous RNA (ceRNA) regulatory network. Histomorphology revealed gill segment swelling and parasitic invasion in the infected group. The analysis identified 18 differentially expressed miRNAs (DEMs), 214 lncRNAs (DELs), 2501 genes (DEGs), and 7 circRNAs (DECs) in the infected group. Gene Ontology (GO) enrichment analysis revealed that these genes were notably enriched in the Wnt signaling pathway and mTOR signaling pathway. The co-expression networks (lncRNA/circRNA-miRNA-mRNA) were constructed based on correlation analysis of the differentially expressed RNAs. Further analysis suggested that the LOC105418663-circ_0000361-fru-miR-204a-fzd3a ceRNA axis was potentially involved in the regulation of immune responses against C. irritans infection. Finally, the expression levels of DEG, DEL, and DEM were validated. This study reveals the regulatory mechanism of a candidate ceRNA network, providing insights into the potential mechanism of T. rubripes' infection with C. irritans.

COULD THE ACUTE Strongyloides venezuelensis INFECTION CAUSE NON-REVERSIBLE HOST MORPHOLOGICAL CHANGES?

Although research has investigated the host-parasite relationship in Strongyloides venezuelensis infection in the scope of its immunological implications, the morphological consequences of this response for the host organism are yet to be explored. Our objective was to perform an organ morphometric analysis in Wistar rats infected with the intestinal parasite Strongyloides venezuelensis compared with infected rats treated with ivermectin. Twenty-six animals composed three groups: control (non-infected), infected (infected with 2,000 Strongyloides venezuelensis larvae), and infected treated (infected with 2,000 Strongyloides venezuelensis larvae and treated with ivermectin). All rodents were killed 21 days after infection and morphometric analysis of different organs was performed. The results showed significantly higher body and fecal weight in the infected-treated group. The weight of the small intestine increased considerably in the infected group and decreased in the infected-treated group. Pancreas, right kidney, and heart volume increased in the infected group compared with the control group. Despite treatment, the volumes of the stomach, brain, and left kidney increased in both the infected groups compared with the control group indicating the possibility of non-reversible host morphological adaptations. S. venezuelensis infection can augment both, volume and weight of organs – not necessarily related to the Strongyloides expulsion process – even if the acute infection had been in remission. A potential explanation for these host adaptations, including the occurrence of organ plasticity, are briefly discussed. The following steps encompass a histological analysis to verify the occurrence of hypertrophy/hyperplasia and observe if such morphological alterations remain after infection.