Immunofluorescence Research Articles

Expansion microscopy reveals characteristic ultrastructural features of pathogenic budding yeast species.

Candida albicans is the most prevalent fungal pathogen associated with candidemia. Similar to other fungi, the complex life cycle of C. albicans has been challenging to study with high-resolution microscopy due to its small size. We employed ultrastructure expansion microscopy (U-ExM) to directly visualise sub-cellular structures at high resolution in the yeast and during its transition to hyphal growth. NHS-ester pan-labelling in combination with immunofluorescence (IF) via snapshots of various mitotic stages provided a comprehensive map of nucleolar and mitochondrial segregation dynamics and enabled the resolution of inner and outer plaque of spindle pole bodies (SPBs). Analyses of microtubules (MTs) and SPBs suggest that C. albicans displays side-by-side SPB arrangement with a short mitotic spindle and longer astral MTs (aMTs) at the pre-anaphase stage. Modifications to the established U-ExM protocol enabled the expansion of six other human fungal pathogens, revealing that the side-by-side SPB configuration is a plausible conserved feature shared by many fungal species. We highlight the power of U-ExM to investigate sub-cellular organisation at high resolution and low cost in poorly studied and medically relevant microbial pathogens.

Advancing cellular insights: Super-resolution STORM imaging of cytoskeletal structures in human stem and cancer cells

Fluorescence microscopy is an important tool for cell biology and cancer research. Present-day approach of implementing advanced optical microscopy methods combined with immunofluorescence labelling of specific proteins in cells is now able to deliver optical super-resolution up to ∼25 nm. Here we perform super-resolved imaging using standard immunostaining protocol combined with easy stochastic optical reconstruction microscopy (easySTORM) to observe structural differences of two cytoskeleton elements, actin and tubulin in three different cell types namely human bone marrow-derived mesenchymal stem cells (MSCs), human glioblastoma (U87MG) and breast cancer (MDAMB-231) cells. The average width of the actin bundle obtained from STORM images of stem cells is observed to be larger than the same for U87MG and MDAMB-231 cells. No significant difference is however noticed in the width of the tubulin within the same cells. We also study the functional effect on the 2D migration potential of MDAMB-231 cells silenced for NICD1 and β-catenin. Although similar migration speed is observed for cells with the above two conditions compared to their control cells, easySTORM images show that widths of the actin in MDAMB-231 cells in β-catenin silenced is significantly lower than the same in control cells. Such minute differences however are not observable in widefield images. The outcome of our easySTORM investigation should benefit the researchers carrying out detailed investigations of the cellular structure and potential therapeutic applications.

HSPB8 attenuates lipopolysaccharide‑mediated acute lung injury in A549 cells by activating mitophagy.

Sepsis is a life‑threatening multiple organ failure disease caused by an uncontrolled inflammatory response and can progress to acute lung injury (ALI). Heat‑shock protein B8 (HSPB8) serves a cytoprotective role in multiple types of diseases; however, to the best of our knowledge, the regulatory role of HSPB8 in sepsis‑induced ALI remains unclear. A549 human alveolar type II epithelial cells were treated with lipopolysaccharide (LPS) for 24 h to simulate a sepsis‑induced ALI model. Cell transfection was performed to overexpress HSPB8, and cells were treated with mitochondrial division inhibitor‑1 (Mdivi‑1) for 2 h before LPS induction to assess the underlying mechanism. Protein expression was evaluated using western blotting and an immunofluorescence assay. Cytokines were examined using ELISA assay kits and antioxidant enzymes were examined using their detection kits. Cell apoptosis was detected using flow cytometry. The mitochondrial membrane potential was detected by JC‑1 staining. HSPB8 was upregulated in A549 cells treated with LPS and HSPB8 overexpression attenuated LPS‑induced inflammatory cytokine levels, oxidative stress and apoptosis in A549 cells. LPS inhibited mitophagy and reduced the mitochondrial membrane potential in A549 cells, which was partly inhibited by HSPB8 overexpression. Furthermore, Mdivi‑1 decreased the inhibitory effect of HSPB8 on the inflammatory response, oxidative stress and apoptosis in LPS‑treated A549 cells. In conclusion, HSPB8 overexpression attenuated the LPS‑mediated inflammatory response, oxidative stress and apoptosis in A549 cells by promoting mitophagy, indicating HSPB8 as a potential therapeutic target in sepsis‑induced ALI.

Based on NF-κB and Notch1/Hes1 Signaling Pathways, the Mechanism of Artesunate on Inflammation in Osteoporosis in Ovariectomized Rats was Investigated.

Artesunate (ART) has the potential to modulate the nuclear factor kappa B (NF-κB) and Notch1/Hes1 signaling pathways, which play crucial roles in the pathogenesis of osteoporosis. This study aims to explore whether ART participates in the progression of osteoporosis by regulating these signaling pathways. In the in vitro experiments, we treated bone marrow mesenchymal stem cells (BMSCs) with different concentrations of ART (0, 3, 6, 12 µM) and evaluated osteogenic differentiation using alkaline phosphatase staining (ALP) and alizarin red S staining (ARS) staining. The expression levels of osteocalcin (OCN), RUNT-related transcription factor 2 (RUNX2), osteoprotegerin (OPG), and receptor activator of the nuclear factor kappa ligand (RANKL) were detected by real-time quantitative PCR (RT-qPCR). The effects of ART on NF-κB p65 and Notch1 protein expression were analyzed by Western blot (WB) and immunofluorescence (IF). In the in vivo experiments, a postmenopausal osteoporosis rat model was established via ovariectomy. Bone tissue pathological injury was evaluated using hematoxylin eosin (HE) staining. Serum ALP levels were measured using a kit, bone density was determined by dual-energy X-ray absorptiometry, and serum levels of bone gla protein (BGP), OPG, RANKL, tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), and IL-1β were measured by enzyme-linked immunosorbent assay (ELISA). Additionally, the expression of NF-κB p65 and Notch1 in tissues was assessed by immunohistochemistry. In vitro experiments revealed that compared to the control group, ART dose-dependently promoted BMSCs proliferation and enhanced their osteogenic differentiation capability. The expression of OCN, RUNX2, and OPG significantly increased in the ART-treated group, while RANKL expression decreased significantly (p < 0.05). ART significantly inhibited the expression of NF-κB p65 and Notch1/Hes1 signaling pathway proteins (p < 0.05). Compared to ART treatment alone, combined treatment with ART and phorbol myristate acetate (PMA) or valproic acid (VPA) resulted in increased expression of NF-κB p65 and Notch1 proteins and decreased osteogenic differentiation capability (p < 0.05). In vivo experiments showed that in rats treated with ART, bone damage was significantly reduced, bone density and mineral content were restored considerably, and the expression of inflammatory factors (TNF-α, IL-6, IL-1β) decreased significantly (p < 0.05). Additionally, ART treatment significantly reduced the expression of NF-κB p65 and Notch1 proteins, increased OPG expression, and decreased BGP and RANKL levels (p < 0.05). In summary, ART facilitates the osteogenic differentiation of BMSCs by inhibiting the NF-κB and Notch1/Hes1 signaling pathways, thereby exerting significant protective effects against osteoporosis.

Promising response of proliferative glomerulonephritis with monoclonal IgG deposits to low-dose daratumumab: a case report

Proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID) is a rare disease without standardized treatment modalities. Daratumumab is a human IgG monoclonal anti-CD38 antibody that has been demonstrated to be highly effective and safe in the treatment of PGNMID. This article reports a 66-year-old female who suffered from edema in both lower limbs and face for 6 years with mild proteinuria and hypoproteinemia. Renal biopsy displayed eight glomeruli, among which two presented with glomerulosclerosis, and the remaining six exhibited moderate diffuse hyperplasia of glomerular mesangial cells and stroma with endothelial cell proliferation. Immunofluorescence microscopy revealed lumpy and diffuse deposits of C3, C1q, IgG, and κ light chain in the glomerular mesangium, with strongly positive staining for IgG3 and varying degrees of weak to negative staining for IgG1, IgG2, IgG4, and λ light chain. Additionally, ultrastructural analysis unveiled that the glomerular basement membrane was segmentally thickened, accompanied by diffuse pedicle fusion, segmental tethered insertion, subendothelial deposits, and electron-dense material in tethered areas. The patient received a total dose of 800 mg of daratumumab (400 mg daily for two consecutive days), as well as daily prednisone (25 mg) and valsartan (80 mg), for treatment and achieved complete remission after three-month follow-up. This case represents an early attempt to treat PGNMID with low-dose daratumumab but requires long-term follow-up.

The Generation and Characterization of Monoclonal Antibodies against the MPXV A29L Protein

Mpox (formerly known as monkeypox) is a zoonotic disease caused by monkeypox virus (MPXV), a DNA virus belonging to the Orthopoxvirus genus, in the Poxviridae family. The disease constitutes a moderate risk to public health at the global level. The MPXV A29L protein plays a crucial role in coordinating virion assembly and facilitating important virus-host interactions. This study focused on the expression, purification, and recombinant protein synthesis of the A29L protein of MPXV using prokaryotic systems. Using hybridoma technology, we successfully generated the monoclonal antibodies (mAbs) 1E12 and 4B2, which specifically recognize the A29L protein. These mAbs were found to be suitable for use in indirect immunofluorescence assays (IFA), Western blotting, and immunoprecipitation (IP). Our investigation also revealed that mAbs 1E12 and 4B2 could detect the A27L protein, a homologous protein found in the vaccinia virus Western Reserve (VACV WR) strain, using IFA, Western blotting, and immunoprecipitation (IP). Using mAbs 1E12 and 4B2 as primary immunological probes, A27L protein expression was detected as early as 6 h postinfection with VACV WR, with increasing protein levels being observed throughout the infection. This study enhances our understanding of the protein structure and function of MPXV and contributes to the development of specific MPXV detection methods.

Link Between Autoimmunity and Epilepsy: Neuronal Autoantibodies

Introduction: Autoimmune epilepsy remains under-recognized, and its true incidence remains uncertain. Objective: This study aimed to determine the prevalence of neuronal autoantibodies in patients with epilepsy of unknown etiology. Materials and Methods: An observational, longitudinal, prospective, and analytical study was conducted to assess the presence of autoantibodies associated with autoimmune encephalitis, glutamic acid decarboxylase-65 (GAD65), and onconeural antibodies in the serum and cerebrospinal fluid of consecutive patients with epilepsy of unknown etiology. Results: Sixty patients and 80 controls (30 healthy individuals, 30 with multiple sclerosis, 10 with systemic lupus erythematosus, and 10 with Sjögren&amp;apos;s syndrome) were included to detect neuronal antibodies. Among epilepsy patients, 28 out of 60 (47%) tested positive for antibodies against N-methyl-D-aspartate receptor (NMDAR), contactin-associated protein 2 (CASPR2), leucine-rich glioma-inactivated 1 (LGI1), and glutamic acid decarboxylase (GAD), which was significantly higher (p &amp;lt; 0.001) than in the combined control cohort. No onconeural antibodies were detected in epilepsy patients except for 6 cases of epilepsy, 1 case of multiple sclerosis, and 3 cases of lupus with positive GAD by immunofluorescence assay and immunoblotting. There was no significant difference in antibody incidence between male and female epilepsy patients. The incidence of positive autoantibodies was significantly higher in patients with focal epilepsy compared to those with generalized epilepsy (p &amp;lt; 0.01). Conclusions: The findings indicate the presence of antibodies against NMDAR, VGKC-associated proteins (LGI1, CASPR2), and intracellular antigens (GAD65) in the serum and cerebrospinal fluid of patients with epilepsy, suggesting an autoimmune etiology. These results underscore the need for further research to elucidate the role of autoantibodies in epilepsy pathogenesis and to explore immunotherapeutic interventions.

Targeting inflammation through inhibition of COX-2 by substituted 4-thiazolidinone analogues: in-vitro, in-vivo and in-silico studies

The prolonged or chronic use of anti-inflammatory agents that are being used clinically is highly unsafe. This flaw or disadvantage has motivated scientists to create new heterocyclic compounds with minimal toxicity and possible anti-inflammatory effects. The design and synthesis of ten 4-thiazolidinone containing pyridine derivatives are reported in the current study article. After conducting an in vitro study, it was discovered that they had anti-inflammatory potential. The compounds were analysed for the COX-2 inhibitory activity. VSA6 found to be most potent candidate, screened further. Also. VSA6 emerged as most potent inhibitor against COX-2 with IC50 of 17.32±1.06µM. Further the antioxidant potential of the candidates was analysed in-vitro data suggested that, synthesized compounds showed the anti-oxidant activity with VSA6, and VSA10 being remarkably potent compounds with IC50 values of 34.39 and 37.32 µM respectively. In RAW 264.7 cells, VSA6 demonstrated dose-dependent suppression of mitochondrial superoxide generation at concentrations of 10 and 20 µM. It decreased intracellular expression of the LPS induced reactive oxygen species; mitochondria induced superoxide, MAPK7 and NF-κβ. The molecule also diminished the expression of extracellular of TNF-α, IL-6, MAPK7, NF-κβ and COX-2 and enhanced the expression of anti-oxidant enzymes i.e. GSH and SOD2. To further validate the COX-2 inhibitory activity of VSA6, gene and protein level expression study was conducted; VSA6 decreased the LPS induced COX-2 expression analysed by flow cytometer, immunofluorescence assay and RT-qPCR. The most efficient compound showed encouraging anti-inflammatory action when tested for in vivo anti-inflammatory potential in carrageenan induced model. To find out how this developed compound interacted with COX-2, an anti-inflammatory target, molecular docking analysis was used. According to the findings, the majority of the compounds could make good candidates for the creation of brand-new anti-inflammatory drugs.

NG2-Glia Cause Diabetic Blood-Brain Barrier Disruption by Secreting MMP-9.

Disorders of the blood-brain barrier (BBB) arising from diabetes mellitus are closely related to diabetic encephalopathy. Previous research has suggested that neuron-glia antigen 2 (NG2)-glia plays a key role in maintaining the integrity of the BBB. However, the mechanism by which NG2-glia regulates the diabetic BBB remains unclear. Type 2 diabetes mellitus (T2DM) db/db mice and db/m mice were used. Evans-Blue BBB permeability tests and transmission electron microscopy techniques were applied. Tight junction proteins were assessed by immunofluorescence and transmission electron microscopy. NG2-glia number and signaling pathways were evaluated by immunofluorescence. Detection of matrix metalloproteinase-9 (MMP-9) in serum was performed using enzyme-linked immunosorbent assay (ELISA). In T2DM db/db mice, BBB permeability in the hippocampus significantly increased from 16 weeks of age, and the structure of tight junction proteins changed. The number of NG2-glia in the hippocampus of db/db mice increased around microvessels from 12 weeks of age. Concurrently, the expression of MMP-9 increased in the hippocampus with no change in serum. Sixteen- week-old db/db mice showed activation of the Wnt/β-catenin signaling in hippocampal NG2-glia. Treatment with XAV-939 improved structural and functional changes in the hippocampal BBB and reduced MMP-9 secretion by hippocampal NG2-glia in db/db mice. It was also found that the upregulation of β-catenin protein in NG2-glia in the hippocampus of 16-week-old db/db mice was significantly alleviated by treatment with XAV-939. The results indicate that NG2-glia can lead to structural and functional disruption of the diabetic BBB by activating Wnt/β-catenin signaling, upregulating MMP-9, and degrading tight junction proteins.

Improved whole-mount immunofluorescence protocol for consistent and robust labeling of adult Drosophila melanogaster adipose tissue.

Energy storage and endocrine functions of the Drosophila fat body make it an excellent model for elucidating mechanisms that underlie physiological and pathophysiological organismal metabolism. Combined with Drosophila's robust genetic and immunofluorescence microscopy toolkits, studies of Drosophila fat body function are ripe for cell biological analysis. Unlike the larval fat body, which is easily removed as a single, cohesive sheet of tissue, isolating intact adult fat body proves to be more challenging, thus hindering consistent immunofluorescence labeling even within a single piece of adipose tissue. Here, we describe an improved approach to handling Drosophila abdomens that ensures full access of the adult fat body to solutions generally used in immunofluorescence labeling protocols. In addition, we assess the quality of fluorescence reporter expression and antibody immunoreactivity in response to variations in fixative type, fixation incubation time, and detergent used for cellular permeabilization. Overall, we provide several recommendations for steps in a whole mount staining protocol that results in consistent and robust immunofluorescence labeling of the adult Drosophila fat body.

Evaluation of the Accuracy of Estimated Endpoint Titer of NOVA View in Indirect Immunofluorescent Antinuclear Antibody Testing

For antinuclear antibody (ANA) screening, the gold standard method is an indirect immunofluorescence assay (IIFA) using HEp-2 cells, and a serial dilution test is needed to determine the endpoint titer. We aimed to evaluate the accuracy of the estimated endpoint titer (eEPT) by the NOVA View system, by comparing it with the EPT by the serial dilution method (dEPT). The endpoint titers of a total of 1518 ANA positive cases with five major patterns including speckled, homogeneous, centromere, nucleolar, and nuclear dots patterns were determined using both the estimation function and the serial dilution method by the NOVA View system. A significant correlation between the light intensity unit (LIU) values and dEPTs was identified in all five patterns with high ρ values, ranging from 0.666 to 0.832. However, the overall exact match rate between dEPT and eEPT was 22.1% (336/1518), with the ±one-titer match rate being highest in the centromere pattern (62.8%, 81/129), and lowest in the homogeneous pattern (37.6%, 200/532). This suggests that while LIU values correlate well with dEPT, there are discrepancies in numerical agreement. Most cases that did not show an exact match, showed one-to-three-titer overestimations by eEPT. Therefore, adjusting eEPT downward significantly improved the concordance rates with dEPTs. Further investigation for an appropriate cutoff of LIU values for determining eEPT should be performed for clinical application and contribution to the standardization of the ANA titer.

A case report of lymphoproliferative disease in brain following therapies with mycophenolate Mofetil and Fingolimod and literature review

Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis is an autoimmune disorder. With the method of indirect immunofluorescence assay (IIF), more anti-NMDAR encephalitis patients have been discovered when its first onset. But it was rare that anti-NMDAR encephalitis overlapped with multiple sclerosis (MS) documented in literatures. Here, we present a case who initially developed anti-NMDAR encephalitis and MS. Furthermore, we concluded the characteristics of patients who were diagnosed as anti-NMDAR encephalitis overlapping with MS. Additionally, due to the relapsing process, mycophenolate mofetil and sequentially fingolimod for the treatment were taken, which subsequently led to the development of a lymphoproliferative disease in his brain and other organs. This case illustrates the complex role of immunosuppressive agents.

Clinical features of anti-neurofascin-155 antibody positive autoimmune nodopathy in 6 children

Objective: To analyze the clinical features of anti-neurofascin-155 (NF155) antibody positive autoimmune nodopathy in children. Methods: This was a case series study. A total of 6 children who were diagnosed accurately as anti-NF155 antibody positive autoimmune nodopathy by cell immunofluorescence assay at the Children's Hospital of Fudan University from January 2020 to December 2023 were collected. This study retrospectively analyzed 6 pediatric children's clinical manifestations, laboratory and electrophysiological examination results, and treatment outcomes. Results: Among 6 children with anti-NF155 antibody positive autoimmune nodopathy, there were 4 boys and 2 girls. The onset age of 6 children ranged from 3 years and 8 months to 12 years. All 6 children had extremity weakness (more severe in the distal and the lower extremities than in the upper extremities), 5 children had sensory deficits such as numbness or pain in the extremities, 4 children had tremors and ataxia, 3 children had cranial nerve involvement. Among the 6 children, 4 children had protein-cell separation in cerebrospinal fluid examinations. Among the 6 children, 1 child had central nervous system demyelination, the brain magnetic resonance imaging showed multiple abnormal signals in the bilateral cerebral hemispheres. Four children showed motor and sensory nerve damage in electrophysiological examination, and 2 children only showed motor nerve damage. Three children showed myelin and axonal damage, and 3 children only showed axonal damage. Among the 6 children, 5 children were treated with intravenous immunoglobulin and steroids. Among them, 2 children underwent plasma exchange due to poor efficacy, and subsequently, rituximab was added. There was 1 child changed the treatment with olfatomumab since the symptoms did not significantly improve after using rituximab. After treatment for 4-15 months, 2 children had no clinical symptoms, 1 child had improvement in clinical symptoms, 2 children had no significant improvement in clinical symptoms, and 1 child who did not receive the immunotherapy had no significant change in clinical symptoms. Conclusions: Anti-NF155 antibody positive autoimmune nodopathy in children presents with varying degrees of clinical manifestations. It is mainly characterized by extremity weakness, numbness and pain, often accompanied bytremorsand ataxia. Some pediatric patients may also have central nervous system demyelination. Cerebrospinal fluid and electrophysiological examination are important auxiliary examination methods. If steroid therapy is not effective, plasma exchange and rituximab treatment should be used as soon as possible.

Hemato-Renal Profile of Proliferative Glomerulonephritis with Monoclonal Immunoglobulin Deposits

Background Proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID) is a rare entity classified under the umbrella of monoclonal gammopathy of renal significance. The clinical implications of circulating monoclonal immunoglobulin (MIg), light chain restriction on immunofluorescence (IF) microscopy, histopathological pattern, and type of therapy on renal outcomes are not clearly defined. Materials and Methods Sixteen patients of PGNMID diagnosed between 2013 and 2020 were included from a biopsy registry of 11,459 patients at a single center. Follow-up data was collected from electronic medical records until June 2021. Results The mean age of the cohort was 41.7 ± 13.5 years. Forty-four (7/16) percent showed monoclonal protein on serum or urine electrophoresis, 25% (3/12) had IgG kappa by serum immunofixation electrophoresis (IFE) and 38% (5/13) had abnormal kappa: lambda free light chain (FLC) ratio. The predominant light microscopy pattern, membranoproliferative glomerulonephritis (MPGN) was seen in 7/16 (43.7%) patients. The predominant heavy chain detected by IF microscopy was IgG (13/16, 81.3%). Kappa and lambda light chain restriction were seen in 56.3 (9/16) and 43.8 (7/16) percent of patients respectively. Circulating monoclonal kappa light chains were detected in 50 and 29% of kappa-PGNMID patients by IFE and FLC assay respectively. None of the lambda-PGNMID patients had detectable circulating monoclonal lambda light chains. Patients with circulating MIg had more proteinuria, lower estimated glomerular filtration rate, and a higher percentage of plasma cells on bone marrow biopsy. Thirty-eight percent of our cohort (5/13) progressed to kidney failure over a median (range) period of 3 (IQR, 1-7) months. Of these, 4/5 received immunosuppression, and 1/5 were treated with plasma cell-targeted chemotherapy. Conclusion PGNMID is a rare disease with a biopsy incidence of 0.1%. Only a quarter of patients with PGNMID have circulating MIg. Presence of circulating MIg, type of monoclonal light chain restriction in kidney biopsy, and type of therapy did not predict renal outcomes. Patients with MPGN pattern had favorable renal outcomes despite a higher degree of proteinuria at presentation.

Upregulation of peroxisome proliferator-activated receptor γ with resorcinol alleviates reactive oxygen species generation and lipid accumulation in neuropathic lysosomal storage diseases

Neuropathic lysosomal storage diseases (NLSDs), including ceroid lipofuscinosis neuronal 3 (CLN3) disease and Gaucher disease type 2 (GD2), are typically present in adolescents; however, there are no approved therapies. CLN3 disease is the most common of the 13 types of neuronal ceroid lipofuscinosis, and Gaucher disease is the most common type of lysosomal storage disease. These NLSDs share oxidative stress and lysosomal dysfunction with Parkinson’s disease. In this study, we used patient-derived cells (PDCs) and resorcinol to develop a therapeutic agent based on peroxisome proliferator-activated receptor γ (PPARγ) activation. PPARγ is a major regulator of autophagy and reactive oxygen species (ROS). Resorcinol, a polyphenolic compound, has been reported to exhibit PPARγ agonistic potential. Protein levels were analyzed by immunoblotting and immunofluorescence microscopy. Changes in cellular metabolism, including ROS levels, lipid droplet content, and lysosomal activity, were measured by flow cytometry. Resorcinol reduced ROS levels by suppressing hypoxia-inducible factor 1α levels in CLN3-PDCs. Resorcinol upregulated autophagy and reduced lipid accumulation in CLN3-PDCs; however, these effects were abolished by autophagy inhibitors. Resorcinol increased nuclear PPARγ levels in CLN3-PDCs, and PPARγ antagonists abolished the therapeutic effects of resorcinol. Moreover, Resorcinol upregulated nuclear PPARγ levels and lysosomal activity in GD2-PDCs, and reduced lipid accumulation and ROS levels. In summary, resorcinol alleviated the shared pathogenesis of CLN3 disease and GD2 through PPARγ upregulation. These findings suggest that resorcinol is a potential therapeutic candidate for alleviating NLSD progression.

The Helicobacter pylori infection alters the intercellular junctions on the pancreas of gerbils (Meriones unguiculatus)

Helicobacter pylori is a common resident in the stomach of at least half of the world’s population and recent evidence suggest its emergence in other organs such as the pancreas. In this organ, the presence of H. pylori DNA has been reported in cats, although the functional implications remain unknown. In this work, we determined distinct features related to the H. pylori manifestation in pancreas in a rodent model, in order to analyse its functional and structural effect. Gerbils inoculated with H. pylori exhibited the presence of this bacterium, as revealed by the expression of some virulence factors, as CagA and OMPs in stomach and pancreas, and confirmed by urease activity, bacterial culture, PCR and immunofluorescence assays. Non-apparent morphological changes were observed in pancreatic tissue of infected animals; however, delocalization of intercellular junction proteins (claudin-1, claudin-4, occludin, ZO-1, E-cadherin, β-catenin, desmoglein-2 and desmoplakin I/II) and rearrangement of the actin-cytoskeleton were exhibited. This structural damage was consistent with alterations in the distribution of insulin and glucagon, and a systemic inflammation, event demonstrated by elevated IL-8 levels. Overall, these findings indicate that H. pylori can reach the pancreas, possibly affecting its function and contributing to the development of pancreatic diseases.Graphical

TSP50 facilitates breast cancer stem cell-like properties maintenance and epithelial-mesenchymal transition via PI3K p110α mediated activation of AKT signaling pathway

BackgroundStudies have confirmed that epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC)-like properties are conducive to cancer metastasis. In recent years, testes-specific protease 50 (TSP50) has been identified as a prognostic factor and is involved in tumorigenesis regulation. However, the role and molecular mechanisms of TSP50 in EMT and CSC-like properties maintenance remain unclear.MethodsThe expression and prognostic value of TSP50 in breast cancer were excavated from public databases and explored using bioinformatics analysis. Then the expression of TSP50 and related genes was further validated by quantitative RT-PCR (qRT-PCR), Western blot, and immunohistochemistry (IHC). In order to investigate the function of TSP50 in breast cancer, loss- and gain-of-function experiments were conducted, both in vitro and in vivo. Furthermore, immunofluorescence (IF) and immunoprecipitation (IP) assays were performed to explore the potential molecular mechanisms of TSP50. Finally, the correlation between the expression of TSP50 and related genes in breast cancer tissue microarray and clinicopathological characteristics was analyzed by IHC.ResultsTSP50 was negatively correlated with the prognosis of patients with breast cancer. TSP50 promoted CSC-like traits and EMT in both breast cancer cells and mouse xenograft tumor tissues. Additionally, inhibition of PI3K/AKT partly reversed TSP50-induced activation of CSC-like properties, EMT and tumorigenesis. Mechanistically, TSP50 and PI3K p85α regulatory subunit could competitively interact with the PI3K p110α catalytic subunit to promote p110α enzymatic activity, thereby activating the PI3K/AKT signaling pathway for CSC-like phenotypes maintenance and EMT promotion. Moreover, IHC analysis of human breast cancer specimens revealed that TSP50 expression was positively correlated with p-AKT and ALDH1 protein levels. Notably, breast cancer clinicopathological characteristics, such as patient survival time, tumor size, Ki67, pathologic stage, N stage, estrogen receptor (ER) and progesterone receptor (PR) levels, correlated well with TSP50/p-AKT/ALDH1 expression status.ConclusionThe effects of TSP50 on EMT and CSC-like properties promotion were verified to be dependent on PI3K p110α. Together, our study revealed a novel mechanism by which TSP50 facilitates the progression of breast cancer, which can provide new insights into TSP50-based breast cancer treatment strategies.

Identification of tumor-specific T cell signature predicting cancer immunotherapy response in bladder cancer by multi-omics analysis and experimental verification

BackgroundNumerous gene signatures predicting the prognosis of bladder cancer have been identified. However, a tumor-specific T cell signature related to immunotherapy response in bladder cancer remains under investigation.MethodsSingle-cell RNA and TCR sequencing from the Gene expression omnibus (GEO) database were used to identify tumor-specific T cell-related genes in bladder cancer. Subsequently, we constructed a tumor-specific T cell signature (TstcSig) and validated its clinical relevance for predicting immunotherapy response in multiple immunotherapy cohorts. Further analyses explored the immune characteristics of TstcSig in bladder cancer patients from other cohorts in the TCGA and GEO databases. Western blot (WB), multicolor immunofluorescence (MIF), qRT-PCR and flow cytometry assays were performed to validate the results of bioinformatics analysis.ResultsThe established TstcSig, based on five tumor-specific T cell-related genes, could predict outcomes in a bladder cancer immunotherapy cohort. This was verified using two additional immunotherapy cohorts and showed better predictive performance compared to 109 published T cell signatures. TstcSig was strongly correlated with immune characteristics such as immune checkpoint gene expression, tumor mutation burden, and T cell infiltration, as validated by single-cell and spatial transcriptomics datasets. Notably, the positive correlation between TstcSig and T cell infiltration was confirmed in the TCGA cohort. Furthermore, pan-cancer analysis demonstrated the heterogeneity of the prognostic value of TstcSig. Tumor-specific T cells highly expressed CD27, IFNG, GZMB and CXCL13 and secreted more effector cytokines for tumor cell killing, as validated experimentally.ConclusionWe developed a five-gene signature (including VAMP5, TIGIT, LCK, CD27 and CACYBP) based on tumor-specific T cell-related genes to predict the immunotherapy response in bladder cancer patients.

Tamoxifen metabolites treatment promotes ERα+ transition to triple negative phenotype in vitro, effects of LDL in chemoresistance.

Estrogen receptor-positive (ER+) breast cancer represents about 80 % of cases, tamoxifen is the election neoadjuvant chemotherapy. However, a large percentage of patients develop chemoresistance, compromising recovery. Clinical evidence suggests that high plasmatic levels of low-density lipoproteins (LDL) could promote cancer progression. The present study analyzed the effect of LDL on the primary plasmatic active Tamoxifen´s metabolites resistance acquisition, 4-hydroxytamoxifen (4OH-Tam) and 4-hydroxy-N-desmethyl-tamoxifen (endoxifen), in breast cancer ER+ cells (MCF-7). Two resistant cellular variants, MCF-7Var-H and MCF-7Var-I, were generated by a novel strategy and their phenotype features were evaluated. Phenotypic assessment was performed by MTT assays, cytometry, immunofluorescence microscopy, zymography and protein expression analysis. MCF-7Var-H, generated only with tamoxifen metabolites, showed a critical down-regulation in hormone receptors, augmented migration capacity, metalloprotease 9 extracellular medium excretion, and a mesenchymal morphology in contrast with native MCF-7, suggesting the transition towards Triple-negative breast cancer (TNBC) phenotype. In contrast, MCF-7Var-I which was generated in a high LDL media, showed only a slight upregulation in ER and other less noticeable metabolic adaptations. Results suggest a potential role of transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) in phenotypic differences observed among variants. LDL high or low concentrations during Tamoxifen´s metabolites chemoresistance acquisition leads to different cellular mechanisms related to chemoresistance. A novel adaptative cellular response associated with Nrf2 activity could be implicated.

Integrated on-slide positive controls for immunocytochemistry on cytology slides.

Integrated on-slide positive controls are a standard quality assurance and quality control measure for immunohistochemistry on formalin-fixed paraffin-embedded tissue sections. They ensure identical analytical conditions for the control and patient samples. Our aim was to develop a procedure for preparing integrated on-slide positive controls for immunocytochemistry (ICC) on methanol-fixed cytospins. Leftover diagnostic cytology samples with sufficient cells and confirmed expression of Calretinin, MOC31, TTF1, and hormone receptors were used as control samples. Cells from the control samples were deposited on the peripheral part of objective slides using standard cytocentrifuge equipment. Cytospins were immediately fixed in methanol for at least 30 minutes and then covered with polyethylene glycol (PEG). Completely dry and solid PEG was removed from the central part of the objective slides and stored at room temperature. Patient samples were subsequently added to the central part of a PEG-protected slide, with an appropriate positive control placed on the peripheral part, and then fixed in methanol. Immunocytochemistry was performed on the Ventana/Roche automated platform ULTRA, using optimized and validated protocols for TTF1, hormone receptors, and double immunostaining for Calretinin/MOC31. The quality of ICC reactions for both deposits on the same slide and potential cell carryover was evaluated retrospectively. In the period from October 2021 to December 2023, the majority of integrated positive controls (364/368, 99%) consistently exhibited unequivocally positive reactions for TTF-1 (n = 93), hormone receptors (n = 84), and double staining for Calretinin/MOC31 (n = 191), with easily interpretable ICC reactions on corresponding patient samples. No obvious carryover of cells from the control sample to the patient sample was observed during this period. A novel approach developed for preparing integrated on-slide positive controls for ICC on methanol-fixed cytospins using standard cytocentrifugation is low-cost and can be widely applied in diagnostic cytology laboratories. Simultaneous ICC procedures for the control and patient samples on the same slide ensure identical analytical conditions for both samples, providing the highest level of quality control while reducing costs. Interpreting both ICC reactions on the same slide is time-efficient and convenient.