Challenges and solutions in FISH for formalin-fixed paraffin-embedded tissue: A scoping review.

Fluorescence in situ hybridization (FISH) has revolutionized molecular cytogenetic analysis since the 1980s, enabling precise localization of DNA sequences in cells and tissues. Despite its relevance, applying FISH to formalin-fixed paraffin-embedded (FFPE) tissue samples encounters significant technical challenges. This review addresses the main issues encountered in this context, such as inadequate fixation, contamination, block and slide age, inadequate pretreatment, and FISH technique. Proposed solutions include optimized pretreatment protocols, monitoring of blockage, careful selection of probes, and thorough analysis of results. Implementing good laboratory practices and quality control strategies are essential to ensure reliable results. Additionally, the use of emerging technologies such as artificial intelligence and digital pathology offers new perspectives for improving the efficiency and accuracy of FISH in FFPE samples. This review highlights the importance of a careful and personalized approach to overcome the technical challenges associated with FISH in FFPE samples, strengthening its role in research and clinical diagnosis. RESEARCH HIGHLIGHTS: Few FISH studies on FFPE: The scarcity of studies specifically addressing FISH applications in FFPE tissues highlights a critical gap in the literature. Troubleshooting FISH in FFPE tissues: Identifying and addressing common challenges in FISH techniques when applied to FFPE samples, such as signal quality and hybridization efficiency. Critical aspects of FISH technique: Discuss the main technical considerations crucial for successful FISH in FFPE tissues, including sample preparation, probe selection, and protocol optimization.

Diagnosing B-cell acute lymphoblastic leukemia in 2 pediatric patients with recent SARS-CoV-2 infection.

COVID-19 infection is still a mystery in terms of its long-term effect on health and its consequences on hematological disorders. Prior studies including ours have shown the abnormal changes in hematopoietic cells in COVID-19 patients. In this article, we are presenting 2 cases of pediatric B-lymphoblastic leukemia (B-ALL) with a previous history of COVID-19 infection. The first case describes a 22-month-old boy presenting with lymphadenopathy, neutropenia, and anemia with concurrent COVID-19 infection without any evidence of a hematolymphoid neoplasm as per bone marrow and lymph node biopsy. However, he presented after 2 months with bone marrow biopsy confirming B-ALL. The second case is that of a 4-year-old girl presenting with B-ALL who has had asymptomatic COVID-19 infection 5 months before this current presentation. Both the cases had complete resolution of COVID-19 infection during the time of presentation with acute leukemia. There were notably 2 rare findings along the course of the patients' illnesses. First, the unusual plasmacytosis in the marrow during active COVID-19 infection in the first patient and the second, is predilection of development of B-ALL following COVID-19. In both the cases the fluorescence in situ hybridization (FISH) studies showed pathologic alteration of the RUNX1 gene. Overall, there are no literature to support a causal association between acute B-ALL and COVID-19. The diagnosis of B-ALL in these patients after COVID-19 infection may be totally unrelated. However, if we consider Greaves proposed 2-hit model for childhood acute leukemia, that an infectious agent can precipitate development of B-ALL in a genetically susceptible individual. Alteration of the RUNX1 gene in both the patients, opens a door for further exploration of the "second-hit" hypothesis regarding an infectious agent precipitating development of B-ALL in a genetically susceptible individual.

Species-specific ribosomal RNA-FISH identifies interspecies cellular-material exchange, active-cell population dynamics and cellular localization of translation machinery in clostridial cultures and co-cultures.

The development of synthetic microbial consortia in recent years has revealed that complex interspecies interactions, notably the exchange of cytoplasmic material, exist even among organisms that originate from different ecological niches. Although morphogenetic characteristics, viable RNA and protein dyes, and fluorescent reporter proteins have played an essential role in exploring such interactions, we hypothesized that ribosomal RNA-fluorescence in situ hybridization (rRNA-FISH) could be adapted and applied to further investigate interactions in synthetic or semisynthetic consortia. Despite its maturity, several challenges exist in using rRNA-FISH as a tool to quantify individual species population dynamics and interspecies interactions using high-throughput instrumentation such as flow cytometry. In this work, we resolve such challenges and apply rRNA-FISH to double and triple co-cultures of Clostridium acetobutylicum, Clostridium ljungdahlii, and Clostridium kluyveri. In pursuing our goal to capture each organism's population dynamics, we demonstrate dynamic rRNA, and thus ribosome, exchange between the three species leading to the formation of hybrid cells. We also characterize the localization patterns of the translation machinery in the three species, identifying distinct, dynamic localization patterns among them. Our data also support the use of rRNA-FISH to assess the culture's health and expansion potential, and, here again, our data find surprising differences among the three species examined. Taken together, our study argues for rRNA-FISH as a valuable and accessible tool for quantitative exploration of interspecies interactions, especially in organisms which cannot be genetically engineered or in consortia where selective pressures to maintain recombinant species cannot be used. IMPORTANCE: Though dyes and fluorescent reporter proteins have played an essential role in identifying microbial species in co-cultures, we hypothesized that ribosomal RNA-fluorescence in situ hybridization (rRNA-FISH) could be adapted and applied to quantitatively probe complex interactions between organisms in synthetic consortia. Despite its maturity, several challenges existed before rRNA-FISH could be used to study Clostridium co-cultures of interest. First, species-specific probes for Clostridium acetobutylicum and Clostridium ljungdahlii had not been developed. Second, "state-of-the-art" labeling protocols were tedious and often resulted in sample loss. Third, it was unclear if FISH was compatible with existing fluorescent reporter proteins. We resolved these key challenges and applied the technique to co-cultures of C. acetobutylicum, C. ljungdahlii, and Clostridium kluyveri. We demonstrate that rRNA-FISH is capable of identifying rRNA/ribosome exchange between the three organisms and characterized rRNA localization patterns in each. In combination with flow cytometry, rRNA-FISH can capture sub-population dynamics in co-cultures.

Insights from single-strain and mixed culture experiments on the effects of heatwaves on freshwater flagellates.

The increasing frequency and intensity of heatwaves driven by climate change significantly impact microbial communities in freshwater habitats, particularly eukaryotic microorganisms. Heterotrophic nanoflagellates are important bacterivorous grazers and play a crucial role in aquatic food webs, influencing the morphological and taxonomic structure of bacterial communities. This study investigates the responses of three flagellate taxa to heatwave conditions through single-strain and mixed culture experiments, highlighting the impact of both biotic and abiotic factors on functional redundancy between morphologically similar protist species under thermal stress. Our results indicate that temperature can significantly impact growth and community composition. However, density-dependent factors also had a significant impact. In sum, stabilizing effects due to functional redundancy may be pronounced as long as density-dependent factors play a minor role and can be overshadowed when flagellate abundances increase.

High-grade B-cell lymphoma with 11q aberration in the HIV setting: a clinicopathological study of 10 cases and literature review.

High-grade B-cell lymphoma with 11q aberration (HGBL-11q) is a distinct lymphoma entity according to the 5th edition of the WHO classification of hematolymphoid tumors. It lacks MYC translocation but carries proximal gains and/or telomeric losses of chromosome 11q. This rare type of B-cell lymphoma is less frequently reported in people living with HIV (PLWH), and its exact frequency remains unclear. Our goal was to retrospectively analyze its frequency in a cohort of aggressive B-cell lymphomas in PLWH, including Burkitt lymphoma (BL, n = 35), diffuse large B-cell lymphoma (DLBCL, n = 48), high-grade B-cell lymphoma, not otherwise specified (HGBL-NOS, n = 13), which was diagnosed as AIDS-related lymphoma (ARL) at our institution. In total, 10/96 (10.4%) cases harbored the typical 11q aberration pattern, predominantly those that had been classified as BL (6/35, 17.1%), DLBCL (2/48, 4.2%), and HGBL, NOS (2/13, 15.4%). We also evaluated 7 cases of AIDS-related HGBL-11q (AR-HGBL-11q) reported in the literature. The median age of our cohort was 35 years, and all the patients were male. Most cases (70%) had a history of HIV infection for over 1 year, and all were involved in lymph nodes (100%), frequently involved extranodal sites (60%), and Ann Arbor stage III/IV. In histomorphology, the cases exhibited diverse cytological features, reminiscent of BL (6 cases), DLBCL (2 cases), and HGBL (2 cases). A comparison of the combined cohort of 17 AR-HGBL-11q cases with 11 ARL cases that lacked both MYC rearrangement and 11q aberration at our institution showed that HGBL-11q cases were characterized by strikingly coarse apoptotic debris (P < 0.001), background rich in eosinophils (P = 0.002), higher expression of the germinal centre marker LMO2 (P = 0.080), lower expression of MUM1 (P = 0.004), BCL2 (P = 0.007), and LEF1 (P = 0.080), and lower positivity for EBER in situ hybridisation (P = 0.027). Notably, one case in our series was EBV-positive, a finding not previously reported in the literature. Furthermore, comparing the prognosis between these two groups, AR-HGBL-11q showed a relatively favorable prognosis (P = 0.15), although the difference was not statistically significant. We analyzed this rare lymphoma entity in the HIV setting and highlighted the importance of integrating histomorphological and immunophenotypic features in its diagnosis and classification.

Use of high-resolution fluorescence in situ hybridization for fast and robust detection of SARS-CoV-2 RNAs.

Early, rapid, and accurate diagnostic tests play critical roles not only in the identification/management of individuals infected by SARS-CoV-2, but also in fast and effective public health surveillance, containment, and response. Our aim has been to develop a fast and robust fluorescence in situ hybridization (FISH) detection method for detecting SARS-CoV-2 RNAs by using an HEK 293 T cell culture model. At various times after being transfected with SARS-CoV-2 E and N plasmids, HEK 293 T cells were fixed and then hybridized with ATTO-labeled short DNA probes (about 20 nt). At 4 h, 12 h, and 24 h after transfection, SARS-CoV-2 E and N mRNAs were clearly revealed as solid granular staining inside HEK 293 T cells at all time points. Hybridization time was also reduced to 1 h for faster detection, and the test was completed within 3 h with excellent results. In addition, we have successfully detected 3 mRNAs (E mRNA, N mRNA, and ORF1a (-) RNA) simultaneously inside the buccal cells of COVID-19 patients. Our high-resolution RNA FISH might significantly increase the accuracy and efficiency of SARS-CoV-2 detection, while significantly reducing test time. The method can be conducted on smears containing cells (e.g., from nasopharyngeal, oropharyngeal, or buccal swabs) or smears without cells (e.g., from sputum, saliva, or drinking water/wastewater) for detecting various types of RNA viruses and even DNA viruses at different timepoints of infection.

Cytogenetic analysis and visualization of genetic relationships in wild lilies.

Lilies are highly regarded for their ornamental appeal and striking flowers, which are of significant importance in horticulture. Understanding the genetic makeup of these plants is crucial for breeding and developing new cultivars. This study presents a comprehensive cytogenetic analysis of 45 S and 5 S rDNA loci in 34 wild Lilium species. To reveal the genetic relationships within the genus, advanced visualization methods, such as heatmaps and 3D network plots, were utilized. The results of this study identified both conserved and divergent genetic features, which offer insights into the evolutionary history and potential genetic compatibility of these species. Notably, the clustering of species based on rDNA locus patterns highlights the need for potential taxonomic re-evaluation and reveals candidates for cross-breeding. This integrated approach emphasizes the importance of combining cytogenetic data with traditional morphological classifications to refine our understanding of the Lilium species. Future research should expand the range of analyzed species, incorporate additional molecular markers to further elucidate genetic relationships, and support the development of resilient and diverse ornamental crops. The findings of this study provide a novel framework for genetic analysis of Lilium, offering valuable insights for both scientific understanding and practical breeding programs.

Satellitome Analysis of Adalia bipunctata (Coleoptera): Revealing Centromeric Turnover and Potential Chromosome Rearrangements in a Comparative Interspecific Study.

Eukaryotic genomes exhibit a dynamic interplay between single-copy sequences and repetitive DNA elements, with satellite DNA (satDNA) representing a substantial portion, mainly situated at telomeric and centromeric chromosomal regions. We utilized Illumina next-generation sequencing data from Adalia bipunctata to investigate its satellitome. Cytogenetic mapping via fluorescence in situ hybridization was performed for the most abundant satDNA families. In silico localization of satDNAs was carried out using the CHRISMAPP (Chromosome In Silico Mapping) pipeline on the high-fidelity chromosome-level assembly already available for this species, enabling a meticulous characterization and localization of multiple satDNA families. Additionally, we analyzed the conservation of the satellitome at an interspecific scale. Specifically, we employed the CHRISMAPP pipeline to map the satDNAs of A. bipunctata onto the genome of Adalia decempunctata, which has also been sequenced and assembled at the chromosome level. This analysis, along with the creation of a synteny map between the two species, suggests a rapid turnover of centromeric satDNA between these species and the potential occurrence of chromosomal rearrangements, despite the considerable conservation of their satellitomes. Specific satDNA families in the sex chromosomes of both species suggest a role in sex chromosome differentiation. Our interspecific comparative study can provide a significant advance in the understanding of the repeat genome organization and evolution in beetles.

DEK::AFF2 Fusion-Associated Squamous Cell Carcinoma: A Case Series with Literature Review on an Emerging and Challenging Entity.

PURPOSE: DEK::AFF2 fusion-associated squamous cell carcinoma (DEK::AFF2 SCC), also reported in the literature as low-grade papillary sinonasal (Schneiderian) carcinoma (LGPSC), is a rare, primarily bland-appearing, but locally aggressive neoplasm. Morphologically, these tumors can closely resemble sinonasal papilloma (SP), especially on small or limited biopsy, often leading to misdiagnosis. DEK::AFF2 SCC is devoid of the underlying mutually exclusive EGFR or KRAS driver mutations of SP, suggesting it may represent a distinct unique entity. METHODS: In this study, we conducted a retrospective search of "unusual" SP reported either as atypical, dysplastic, or suspicious for malignant transformation at our institution in the last 13 years (2010-2023), to identify potential cases of DEK::AFF2 SCC. RESULTS: Of the 201 SP cases during this time period, 30 "unusual" SP cases were identified. On morphologic review of these 30 cases, 6 were worrisome for DEK::AFF2 SCC and were selected for AFF2 immunohistochemical stain (IHC), of which 3 cases were positive. All 3 AFF2 IHC positive cases were also positive for DEK::AFF2 fusion by fluorescence in situ hybridization (FISH), thereby, confirming IHC results. CONCLUSIONS: This study highlights that AFF2 IHC can be an invaluable surrogate marker to FISH in identifying DEK::AFF2 SCC in challenging cases to avoid misdiagnosis. Detailed clinical and pathologic data were collected to gain a better understanding of this emerging challenging entity. A literature review was performed to enrich our knowledge of DEK::AFF2 SCC.

Protein Expression, Amplification, and Mutation of HER2 Gene in Canine Primary Pulmonary Adenocarcinomas: Preliminary Results.

Recently, human epidermal growth factor receptor 2 (HER2) has emerged as a therapeutic target of interest for non-small-cell lung cancer in humans. The role of HER2 in canine pulmonary adenocarcinomas is poorly documented. To address this gap, this study employed three methodologies: immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and next-generation sequencing (NGS) to investigate the protein expression, gene amplification, and mutation of HER2 in 19 canine primary pulmonary adenocarcinomas. By IHC, 3 out of 19 cases were overexpressed 3+, 6 were 2+, and 10 were negative. With FISH, 2 cases were amplified (12.5%), 3 were inadequate for the analyses, and the others were non-amplified. With NGS, seven cases were inadequate. All other cases were wild-type, except for one IHC 3+ case, which was amplified with FISH and with a specific mutation already described in human pulmonary adenocarcinoma, V659E. This mutation is probably sensitive to tyrosine kinase inhibitory drugs. These results are similar to those in human medicine and to the few data in the literature on canine lung carcinomas; the presence of 12.5% of amplified cases in dogs lays the foundation for future targeted drugs against HER2 alterations.

Generation of densely labeled oligonucleotides for the detection of small genomic elements.

The genome contains numerous regulatory elements that may undergo complex interactions and contribute to the establishment, maintenance, and change of cellular identity. Three-dimensional genome organization can be explored with fluorescence in situ hybridization (FISH) at the single-cell level, but the detection of small genomic loci remains challenging. Here, we provide a rapid and simple protocol for the generation of bright FISH probes suited for the detection of small genomic elements. We systematically optimized probe design and synthesis, screened polymerases for their ability to incorporate dye-labeled nucleotides, and streamlined purification conditions to yield nanoscopy-compatible oligonucleotides with dyes in variable arrays (NOVA probes). With these probes, we detect genomic loci ranging from genome-wide repetitive regions down to non-repetitive loci below the kilobase scale. In conclusion, we introduce a simple workflow to generate densely labeled oligonucleotide pools that facilitate detection and nanoscopic measurements of small genomic elements in single cells.

HER2 amplification subtype intrahepatic cholangiocarcinoma exhibits high mutation burden and T cell exhaustion microenvironment.

OBJECTIVE: This study aimed to establish a uniform standard for the interpretation of HER2 gene and protein statuses in intrahepatic cholangiocarcinoma (ICC). We also intended to explore the clinical pathological characteristics, molecular features, RNA expression and immune microenvironment of HER2-positive ICC. METHODS: We analyzed a cohort of 304 ICCs using immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) to identify HER2 status. Comprehensive analyses of the clinicopathological, molecular genetic, and RNA expression characterizations of ICCs with varying HER2 statuses were performed using next-generation sequencing. We further investigated the tumor microenvironment of ICCs with different HER2 statuses using IHC and multiplex immunofluorescence staining. RESULTS: HER2/CEP17 ratio of ≥ 2.0 and HER2 copy number ≥ 4.0; or HER2 copy number ≥ 6.0 were setup as FISH positive criteria. Based on this criterion, 13 (4.27%, 13/304) samples were classified as having HER2 amplification. The agreement between FISH and IHC results in ICC was poor. HER2-amplified cases demonstrated a higher tumor mutational burden compared to non-amplified cases. No significant differences were observed in immune markers between the two groups. However, an increased density of CD8 + CTLA4 + and CD8 + FOXP3 + cells was identified in HER2 gene-amplified cases. CONCLUSION: FISH proves to be more appropriate as the gold standard for HER2 evaluation in ICC. HER2 gene-amplified ICCs exhibit poorer prognosis, higher mutational burden, and T cell exhaustion and immune suppressed microenvironment.

[Genetic and clinical characteristics of 46,XX testicular disorders of sex development].

OBJECTIVE: To investigate the genetic and clinical characteristics of 46, XX testicular disorders of sex development (DSD). METHODS: We collected the clinical data on the patients with 46,XX testicular DSD diagnosed in the Center of Reproductive Medicine of the First Affiliated Hospital of Nanjing Medical University from January 2017 to January 2023, and analyzed their genetic and clinical characteristics and the SRY gene chromosomal location for those with SRY-positive. RESULTS: A total of 26 patients were included in this study, all with 46,XX and deletion of the AZFa, b and c regions, with a mean height of (168.3±5.9) cm, body weight of (64.0±7.5) kg, BMI of (22.66±2.79) kg/m2, left testis volume of (2.53±1.16) ml and right testis volume of (2.74±1.34) ml. The semen volume of the patients averaged 1.35 (0.18－2.78) ml, FSH (36.85±18.01) IU/L, LH (19.71±9.71) IU/L, and T (6.08±2.71) nmol/L. The SRY-negative patients had a higher incidence rate of development disorders in the reproductive system than the SRY-positive ones (5/6 vs 3/20, P = 0.004), but no statistically significant differences were observed in the other parameters. The SRY gene was localized at the end of Xp in 13 of the 14 SRY-positive cases, and at chromosome 15 in the other 1. CONCLUSION: 46,XX testicular DSD has some similarity and heterogeneity in genetics and clinical characteristics.

Characteristics and Cytological Analysis of Several Novel Allopolyploids and Aneuploids between Brassica oleracea and Raphanus sativus.

Polyploids are essential in plant evolution and species formation, providing a rich genetic reservoir and increasing species diversity. Complex polyploids with higher ploidy levels often have a dosage effect on the phenotype, which can be highly detrimental to gametes, making them rare. In this study, offspring plants resulting from an autoallotetraploid (RRRC) derived from the interspecific hybridization between allotetraploid Raphanobrassica (RRCC, 2n = 36) and diploid radish (RR, 2n = 18) were obtained. Fluorescence in situ hybridization (FISH) using C-genome-specific repeats as probes revealed two main genome configurations in these offspring plants: RRRCC (2n = 43, 44, 45) and RRRRCC (2n = 54, 55), showing more complex genome configurations and higher ploidy levels compared to the parental plants. These offspring plants exhibited extensive variation in phenotypic characteristics, including leaf type and flower type and color, as well as seed and pollen fertility. Analysis of chromosome behavior showed that homoeologous chromosome pairing events are widely observed at the diakinesis stage in the pollen mother cells (PMCs) of these allopolyploids, with a range of 58.73% to 78.33%. Moreover, the unreduced C subgenome at meiosis anaphase II in PMCs was observed, which provides compelling evidence for the formation of complex allopolyploid offspring. These complex allopolyploids serve as valuable genetic resources for further analysis and contribute to our understanding of the mechanisms underlying the formation of complex allopolyploids.

MYC translocation is a valuable marker for the development and relapse of extramedullary disease in multiple myeloma.

OBJECTIVE: To study the cytogenetic characteristics of extramedullary disease (EMD) in patients with multiple myeloma (MM) and their impact on prognosis. METHODS: Patients with newly diagnosed MM (NDMM) at Peking Union Medical College Hospital (Beijing, China) between June 2007 and December 2019 were recruited for this study. Demographic information, clinical data, fluorescence in situ hybridization (FISH) results of marrow and tissue samples, and survival outcome data were collected. RESULTS: A total of 439 patients with NDMM were divided into those without EMD (non-EMD, n = 339), those with EMD with primary paraosseous plasmacytoma (pEMD-B, n = 48), those with primary EMD with soft-tissue involvement (pEMD-S, n = 33), and those with secondary EMD (sEMD, n = 19). The incidence of EMD was 18.5% (81/439) at diagnosis and 22.8% (100/439) throughout the disease course. Comparison of FISH results showed a higher proportion of RB1 deletion (n = 20; 60.0% vs. 20.0%, p = .013) and MYC translocation (n = 12; 44.4% vs. 12.5%, p = .041) in the extramedullary tissues than in the paired bone marrow samples. At diagnosis, the percentage of MYC translocations in the sEMD group was notably higher than that in the non-EMD group (55.6% vs. 15.5%, p = .012). The median overall survival (OS) of patients with pEMD-S (32 months) and sEMD (17 months) was significantly shorter (both p = .001) than that of non-EMD patients (60 months). CONCLUSION: Soft-tissue EMD can be considered a high-risk condition, even in the era of novel agents. MYC translocation can serve as a valuable marker that correlates with extramedullary spread and relapse in patients with MM and should be considered for inclusion in routine FISH panels in clinical practice.

CAPZB mRNA is a novel biomarker for cervical high-grade squamous lesions.

This study aimed to evaluate the potential of capping protein (actin filament) muscle Z-line subunit ß (CAPZB) messenger ribonucleic acid (mRNA) levels as a biomarker for distinguishing low-grade squamous intraepithelial lesions of the cervix (LSIL) from high-grade squamous intraepithelial lesions of the cervix (HSIL). We collected a total of 166 cervical exfoliated cells and divided them into five groups based on histopathological results. Each sample was divided into two portions, one for fluorescence in situ hybridization (FISH) detection and the other for bisulfite sequencing polymerase chain reaction (BSP) detection. We found that FISH detection of CAPZB mRNA mean fluorescence intensity (MFI) and BSP detection of CAPZB deoxyribonucleic acid (DNA) percentage of methylation rate (PMR) performed as biomarkers for distinguishing HSIL from LSIL, with an area under the receiver operating characteristic curve (AUC), sensitivity, specificity and cut-off value of 0.893, 81.25%, 80.39% and 0.616, 0.794, 64.06%, 81.37% and 0.454, respectively. Furthermore, FISH detection of CAPZB mRNA exhibited a greater AUC (0.893) for the detection of HSIL than the CAPZB DNA methylation method (0.794), indicating the CAPZB mRNA levels can be used as a biomarker for assessing cervical lesions.

The First FISH-Confirmed Non-Canonical Telomeric Motif in Heteroptera: Cimex lectularius Linnaeus, 1758 and C. hemipterus (Fabricius, 1803) (Hemiptera, Cimicidae) Have a 10 bp Motif (TTAGGGATGG)n.

Fluorescence in situ hybridization (FISH) with two different probes, the canonical insect telomeric sequence (TTAGG)n and the sequence (TTAGGGATGG)n, was performed on meiotic chromosomes of two members of the true bug family Cimicidae (Cimicomorpha), the common bed bug Cimex lectularius Linnaeus, 1758 and the tropical bed bug C. hemipterus (Fabricius, 1803), whose telomeric motifs were not known. In both species, there were no hybridization signals with the first probe, but strong signals at chromosomal ends were observed with the second probe, indicating the presence of a telomeric motif (TTAGGGATGG)n. This study represents the first FISH confirmation of the presence of a non-canonical telomeric motif not only for the infraorder Cimicomorpha but also for the suborder Heteroptera (Hemiptera) as a whole. The present finding is of key significance for unraveling the evolutionary shifts in the telomeric sequences in this suborder.

Multiplex Profiling of miR-122 for Preclinical and Clinical Evaluation of Drug-Induced Liver Injury by a Full-Scale Platform.

Diagnostic and monitoring for drug-induced liver injury (DILI) predominantly rely on serum aminotransferases. However, owing to their widespread expression across multiple organs, a significant challenge emerges from the absence of reliable biomarkers for DILI diagnosis. Herein, we introduce a concept for DILI detection, circumventing the nonspecific elevation and delayed release of aminotransferases and then straightforwardly focusing on the core feature of DILI, abnormal gene expression caused by drug overdose. The developed full-scale platform integrates the properties of spherical nucleic acids with elaborately designed fluorescence in situ hybridization sequences, enabling the sensitive and specific profiling of drug-overdosed miR-122 expression alterations across molecular, cellular, organismal, and clinical scales and effectively bypassing the phenotypic features of disease. Furthermore, the diagnostic efficacies of serum and total RNA extracted from both mouse and human blood samples for DILI diagnosis were analyzed using the receiver operating characteristic curve and principal component analysis. We anticipate that this universal platform holds potential in facilitating DILI diagnosis, therapeutic evaluation, and prognosis.

A large colonial choanoflagellate from Mono Lake harbors live bacteria.

As the closest living relatives of animals, choanoflagellates offer insights into the ancestry of animal cell physiology. Here, we report the isolation and characterization of a colonial choanoflagellate from Mono Lake, California. The choanoflagellate forms large spherical colonies that are an order of magnitude larger than those formed by the closely related choanoflagellate Salpingoeca rosetta. In cultures maintained in the laboratory, the lumen of the spherical colony is filled with a branched network of extracellular matrix and colonized by bacteria, including diverse Gammaproteobacteria and Alphaproteobacteria. We propose to erect Barroeca monosierra gen. nov., sp. nov. Hake, Burkhardt, Richter, and King to accommodate this extremophile choanoflagellate. The physical association between bacteria and B. monosierra in culture presents a new experimental model for investigating interactions among bacteria and eukaryotes. Future work will investigate the nature of these interactions in wild populations and the mechanisms underpinning the colonization of B. monosierra spheres by bacteria. IMPORTANCE: The diversity of organisms that live in the extreme environment of Mono Lake (California, USA) is limited. We sought to investigate whether the closest living relatives of animals, the choanoflagellates, exist in Mono Lake, a hypersaline, alkaline, arsenic-rich environment. We repeatedly isolated members of a new species of choanoflagellate, which we have named Barroeca monosierra. Characterization of B. monosierra revealed that it forms large spherical colonies containing diverse co-isolated bacteria, providing an opportunity to investigate mechanisms underlying physical associations between eukaryotes and bacteria.

Polymicrobial consortia in the pathogenesis of biofilm vaginosis visualized by FISH. Historic review outlining the basic principles of the polymicrobial infection theory.

The manuscript disputes the exclusive mono-infectious way of thinking, which presumes that for every infection only one pathogen is responsible and sufficient, when infectious vectors, close contact and reduced immunity meet. In situations involving heavily colonized anatomical sites such an approach often ends in insoluble contradictions. Upon critical reflection and evaluation of 20 years research on spatial organization of vaginal microbiota it is apparent, that in some situations, pathogens may act and operate in permanent, structurally organized consortia, whereas its individual components may be innocuous and innocent, failing to express any pathogenic effect. In these cases, consortia are the true pathogens responsible for many infectious conditions, which usually remain unrecognized as long as improperly diagnosed. The structure of such consortia can be unraveled using ribosomal fluorescence in situ hybridization (FISH). FISH methodology, that not only offers an ex vivo opportunity to recognize bacterial species, but provides unique physical insight into their specific role in the pathogenesis of polymicrobial infections. Ribosomal FISH technique applied to both, women with bacterial vaginosis (BV) and their male partners, has added significantly to our understanding of the pathogenesis of this condition and contributed to appreciating the mechanisms of polymicrobial, community-based infection, potentially leading to therapeutic advances.