Time to heal: inhibiting fibrosis prevents glioblastoma recurrence.

New findings by Watson et al. demonstrate that therapy-induced inflammation and fibrosis potentiate glioblastoma recurrence. Post-treatment fibrotic niches shielded surviving tumor cells from immune surveillance, supported their persistence in a dormant state, and enabled rebound growth. Timely inhibition of inflammation and scarring attenuated recurrence, encouraging the use of new combinatorial approaches in glioblastoma therapy.

Diagnosis and Management of Paradoxical Cerebrospinal Rhinnorhea in Mondini's Dysplasia.

Objectives: To highlight a case of unilateral Mondini's dysplasia and it's potential to manifest as paradoxical cerebrospinal fluid (CSF) rhinorrhoea and recurrent meningitis in an adult. Methods: A single case report with presentation and management of a patient with left sided Mondini's Dysplasia who presented with watery nasal discharge in the background of recurrent meningitis. We review the differential diagnoses and the importance of a multi-disciplinary approach to management. Results: Post-auricular approach was taken and the leak was identified at the footplate of Stapes and sealed with fascia lata. The middle ear was obliterated and blind sac closure was done. The patient made a good recovery. Supplementary Information: The online version contains supplementary material available at 10.1007/s12070-024-04903-5.

Comparative Cross Sectional Prospective Study of Anterior Skull Base Thickness in Spontaneous Cerebrospinal Fluid Rhinorrhoea vs Matched Controls.

Cerebrospinal fluid (Csf) leak is the leakage of CSF from subarachnoid space into the nasal cavity.Csf rhinorrhoea is classified as traumatic and non traumatic causes (Ommaya et al. J Neurol Neurosurg Psychiatry 31(3):214, 1968). Spontaneous csf leaks occur due to increased intracranial pressure. Early diagnosis of spontaneous csf leaks may prevent complications like meningitis. This was a cross sectional prospective study done in a tertiary care hospital. Group A-spontaneous csf leak patients and Group B- Non csf leak matched controls. The anterior skull base thickness from fovea ethmoidalis, cribriform plate and lateral lamella were compared between the groups using high resolution computed tomography of paranasal sinus with 2 mm cuts. The anterior skull base thickness was measured by a senior radiologist in our tertiary centre. In this study, total of forty six patients were included, twentythree in each group. The Mean age in Group A and Group B was 48.95 and 48.78 respectively. Body mass index (BMI) was compared between the two groupsand spontaneous csf leak patients had higher value than non csf leak controls. The mean anterior skull base thickness of Group A (cribriform plate-0.56 mm, lateral lamella-0.66 mm, Fovea ethmoidalis-0.91 mm) was lower than Group B (cribriform plate-0.86 mm, lateral lamella-0.84 mm, Fovea ethmoidalis-0.97 mm) which was statistically significant (p value-< 0.05).

THE PLACE OF SURGERY IN THE MANAGEMENT OF PROLACTIN SECRETING ADENOMAS.

Introduction: Surgery has lost a lot of ground as the main therapy of most prolactinomas as it is clear from the current guidelines in most prolactin secreting adenomas, even in the setting of optic compression. However, we believe that surgery is still an important part in the treatment of this type of adenomas. This study is aimed to define what is the role of pituitary surgery in the current setup of prolactinoma management. Material and methods: In this retrospective, single-center study we analyzed 12 consecutive patients who underwent primary endoscopic transsphenoidal surgery for prolactinomas, between 2013 and 2022. Surgical indication, previous dopamine agonist (DA) treatment, remission rates, surgical complications, pituitary function and imagistic appearance are presented. Results: Of the 12 patients included, 4 had giant PRL and 8 macroadenomas, while 9 of them had previous DA treatment. The main surgical indication was pituitary apoplexy in 5 patients followed by CSF leak after DA treatment, 3 cases, and DA resistance in 3 cases. The main surgical complications were transitory diabetes insipidus in 7 cases. Normalization of prolactin levels was achieved in 2 patients. Conclusions: Surgical intervention should be strongly considered in all patients with neurologic symptoms referable to the lesion, resistance to medical therapy, other treatment failure or with complications after DA treatment. The endoscopic endonasal surgery offers good surgical outcomes with low rates of surgical complications and should remain an open option for specific cases.

Deep Proteome Analysis of Cerebrospinal Fluid from Pediatric Patients with Central Nervous System Cancer.

The cerebrospinal fluid (CSF) is a key matrix for discovery of biomarkers relevant for prognosis and the development of therapeutic targets in pediatric central nervous system malignancies. However, the wide range of protein concentrations and age-related differences in children makes such discoveries challenging. In addition, pediatric CSF samples are often sparse and first prioritized for clinical purposes. The present work focused on optimizing each step of the proteome analysis workflow to extract the most detailed proteome information possible from the limited CSF resources available for research purposes. The strategy included applying sequential ultracentrifugation to enrich for extracellular vesicles (EV) in addition to analysis of a small volume of raw CSF, which allowed quantification of 1351 proteins (+55% relative to raw CSF) from 400 µL CSF. When including a spectral library, a total of 2103 proteins (+240%) could be quantified. The workflow was optimized for CSF input volume, tryptic digestion method, gradient length, mass spectrometry data acquisition method and database search strategy to quantify as many proteins a possible. The fully optimized workflow included protein aggregation capture (PAC) digestion, paired with data-independent acquisition (DIA, 21 min gradient) and allowed 2989 unique proteins to be quantified from only 400 µL CSF, which is a 340% increase in proteins compared to analysis of a tryptic digest of raw CSF.

Profiling neuroinflammatory markers and response to nusinersen in paediatric spinal muscular atrophy.

Neuroinflammation is an emerging clinical feature in spinal muscular atrophy (SMA). Characterizing neuroinflammatory cytokines in cerebrospinal fluid (CSF) in SMA and their response to nusinersen is important for identifying new biomarkers and understanding the pathophysiology of SMA. We measured twenty-seven neuroinflammatory markers in CSF from twenty SMA children at different time points, and correlated the findings with motor function improvement. At baseline, MCP-1, IL-7 and IL-8 were significantly increased in SMA1 patients compared to SMA2, and were significantly correlated with disease severity. After six months of nusinersen treatment, CSF levels of eotaxin and MIP-1ß were markedly reduced, while IL-2, IL-4 and VEGF-A were increased. The decreases in eotaxin and MIP-1ß were associated with changes in motor scores in SMA1. We also detected a transient increase in MCP-1, MDC, MIP-1α, IL-12/IL-23p40 and IL-8 after the first or second injection of nusinersen, followed by a steady return to baseline levels within six months. Our study provides a detailed profile of neuroinflammatory markers in SMA CSF. Our data confirms the potential of MCP-1, eotaxin and MIP-1ß as new neuroinflammatory biomarkers in SMA1 and indicates the presence of a subtle inflammatory response to nusinersen during the early phase of treatment.

Senescent cells promote breast cancer cells motility by secreting GM-CSF and bFGF that activate the JNK signaling pathway.

BACKGROUND: Cellular senescence can be induced in mammalian tissues by multiple stimuli, including aging, oncogene activation and loss of tumor suppressor genes, and various types of stresses. While senescence is a tumor suppressing mechanism when induced within premalignant or malignant tumor cells, senescent cells can promote cancer development through increased secretion of growth factors, cytokines, chemokines, extracellular matrix, and degradative enzymes, collectively known as senescence-associated secretory phenotype (SASP). Previous studies indicated that senescent cells, through SASP factors, stimulate tumor cell invasion that is a critical step in cancer cell metastasis. METHODS: In the current study, we investigated the effect of senescent cells on the motility of breast cancer cells, which is another key step in cancer cell metastasis. We analyzed the motility of breast cancer cells co-cultured with senescent cells in vitro and metastasis of the breast cancer cells co-injected with senescent cells in orthotopic xenograft models. We also delineated the signaling pathway mediating the effect of senescent cells on cancer cell motility. RESULTS: Our results indicate that senescent cells stimulated the migration of breast cancer cells through secretion of GM-CSF and bFGF, which in turn induced activation of the JNK pathway in cancer cells. More importantly, senescent cells promoted breast cancer metastasis, with a minimum effect on the primary tumor growth, in orthotopic xenograft mouse models. CONCLUSIONS: These results have revealed an additional mechanism by which senescent cells promote tumor cell metastasis and tumor progression, and will potentially lead to identification of novel targets for cancer therapies that suppress metastasis, the major cause of cancer mortality.

CSF3R as a potential prognostic biomarker and immunotherapy target in glioma.

Introduction: Gliomas are the most common malignant brain tumors, with complicated etiology and poor prognosis. However, there is still a lack of specific biomarkers for the diagnosis, treatment and prognosis assessment for glioma patients. Hence, the purpose of this study was to screen biomarkers for prognostic assessment and therapeutic interventions in gliomas. Material and methods: We utilized The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) databases to investigate the role of colony-stimulating factor 3 receptor (CSF3R) in glioma. Data analysis was conducted using R, GEPIA 2, TISCH and DepMap. Results: CSF3R was up-regulated in glioma and associated with the clinical pathological features of the patients. Kaplan-Meier survival analysis indicated a significant association between the expression of CSF3R and prognosis in patients. Univariate and multivariate Cox analyses revealed that patients with high expression of CSF3R have a worse prognosis, and the expression of CSF3R was an independent prognostic factor in gliomas. The nomogram constructed based on the expression of CSF3R demonstrated lower 1-, 3-, and 5-year overall survival (OS) in patients with high CSF3R expression. The biological functional analysis of CSF3R demonstrated its association with various immune regulatory signals. Furthermore, CSF3R was linked to the expression of immune checkpoints and resistance to immunotherapy. Notably, CSF3R was predominantly detected in monocytes/macrophages. Conclusions: Our study suggested that CSF3R might potentially function as an independent prognostic factor for glioma and hold promise as a biomarker and target for immunotherapy in glioma.

Interactions of the CSF3R polymorphism and early stress on future orientation: evidence for the differential model of stress-related growth.

AIMS: This study aims to explore the concept of future orientation, which encompasses individuals' thoughts about the future, goal-setting, planning, response to challenges and behavioural adjustments in evolving situations. Often viewed as a psychological resource, future orientation is believed to be developed from psychological resilience. The study investigates the curvilinear relationship between childhood maltreatment and future orientation while examining the moderating effects of genotype. METHODS: A total of 14,675 Chinese adults self-reported their experiences of childhood maltreatment and their future orientation. The influence of genetic polymorphism was evaluated through genome-wide interaction studies (GWIS; genome-wide association study [GWAS] using gene × environment interaction) and a candidate genes approach. RESULTS: Both GWAS and candidate genes analyses consistently indicated that rs4498771 and its linked single-nucleotide polymorphisms, located in the intergenic area surrounding CSF3R, significantly interacted with early trauma to influence future orientation. Nonlinear regression analyses identified a quadratic or cubic association between future orientation and childhood maltreatment across some genotypes. Specifically, as levels of childhood maltreatment increased, future orientation declined for all genotypes. However, upon reaching a certain threshold, future orientation exhibited a rebound in individuals with specific genotypes. CONCLUSIONS: The findings suggest that individuals with certain genotypes exhibit greater resilience to childhood maltreatment. Based on these results, we propose a new threshold model of stress-related growth.

Sepsis surveillance in patients with head-and-neck cancer undergoing chemo-radiation.

BACKGROUND: The infection rate among patients with head-and-neck cancer (HNC) undergoing chemoradiotherapy (CRT) is approximately 19%, with sepsis-related death ranging from 3-9%. A previous study at our institute found a 12% sepsis-related death rate in HNC patients during CRT. The objective of this study is to investigate the utilization of sepsis surveillance and early intervention in reducing the occurrence of sepsis-related deaths in locally advanced HNC patients receiving CRT. METHODS: This retrospective analysis examined 54 patients with locally advanced HNC undergoing CRT who underwent sepsis surveillance between January 2018 and December 2021. The study recorded the utilization of oral and intravenous antibiotics, G-CSF, early admissions and their reasons, and the incidence of early mortality. Data analysis was conducted using SPSS v.24 software. RESULTS: Twenty-one (38.9%) patients were prescribed oral antibiotics, and 14 (25.9%) received G-CSF on an outpatient basis. Twenty-nine (54%) patients required hospital admission. Among the admitted patients, 28 (96%) received intravenous antibiotics, and G-CSF was administered in 18 (62%) patients. In 8 cases, antibiotic treatment was intensified due to persistent fever and deteriorating neutropenia. The median time for receiving antibiotics and G-CSF after starting CRT was 5th week (range: 3-8 weeks). Five patients required readmission. Only one patient succumbed to sepsis. Among the 54 patients, 48 (89%) completed the scheduled RT, while 14 (25.9%) received all 6 cycles of chemotherapy. CONCLUSION: Sepsis surveillance and the prompt use of antibiotics and G-CSF, along with early hospitalization, when necessary, reduces the occurrence of sepsis-related early deaths in HNC patients undergoing CRT.

Unveiling signaling pathways inducing MHC class II expression in neutrophils.

Introduction: Gram-negative bacillary bacteremia poses a significant threat, ranking among the most severe infectious diseases capable of triggering life-threatening sepsis. Despite the unambiguous involvement of neutrophils in this potentially fatal disease, there are limited data about the molecular signaling mechanisms, phenotype, and function of human neutrophils during the early phase of gram-negative bacillary bacteremia. Methods: By using an unbiased proteomics and flow cytometry approach, we identified an antigen-presenting cell (APC)-like phenotype in human peripheral blood neutrophils (PMN) with MHC class II molecule expression in the early phase of bacteremia. Using an in-vitro model of GM-CSF-mediated induction of APC-like phenotype in PMN, we investigated downstream signaling pathways leading to MHC class II expression. Results: GM-CSF stimulation of neutrophils leads to the activation of three major signaling pathways, the JAK-STAT, the mitogen-activated protein kinase (MAPK), and the phosphoinositide 3-kinase (PI3K)-Akt-mTOR pathways, while MHC class II induction is mediated by a MAPK-p38-MSK1-CREB1 signaling cascade and the MHC class II transactivator CIITA in a strictly JAK1/2 kinase-dependent manner. Discussion: This study provides new insights into the signaling pathways that induce MHC class II expression in neutrophils, highlighting the potential for therapeutic targeting of JAK1/2 signaling in the treatment of gram-negative bacteremia and sepsis. Understanding these mechanisms may open up novel approaches for managing inflammatory responses during sepsis.

Therapeutic Effect of Boron Neutron Capture Therapy on Boronophenylalanine Administration via Cerebrospinal Fluid Circulation in Glioma Rat Models.

In recent years, various drug delivery systems circumventing the blood-brain barrier have emerged for treating brain tumors. This study aimed to improve the efficacy of brain tumor treatment in boron neutron capture therapy (BNCT) using cerebrospinal fluid (CSF) circulation to deliver boronophenylalanine (BPA) to targeted tumors. Previous experiments have demonstrated that boron accumulation in the brain cells of normal rats remains comparable to that after intravenous (IV) administration, despite BPA being administered via CSF at significantly lower doses (approximately 1/90 of IV doses). Based on these findings, BNCT was conducted on glioma model rats at the Kyoto University Research Reactor Institute (KUR), with BPA administered via CSF. This method involved implanting C6 cells into the brains of 8-week-old Wistar rats, followed by administering BPA and neutron irradiation after a 10-day period. In this study, the rats were divided into four groups: one receiving CSF administration, another receiving IV administration, and two control groups without BPA administration, with one subjected to neutron irradiation and the other not. In the CSF administration group, BPA was infused from the cisterna magna at 8 mg/kg/h for 2 h, while in the IV administration group, BPA was intravenously administered at 350 mg/kg via the tail vein over 1.5 h. Thermal neutron irradiation (5 MW) for 20 min, with an average fluence of 3.8 × 1012/cm2, was conducted at KUR's heavy water neutron irradiation facility. Subsequently, all of the rats were monitored under identical conditions for 7 days, with pre- and post-irradiation tumor size assessed through MRI and pathological examination. The results indicate a remarkable therapeutic efficacy in both BPA-administered groups (CSF and IV). Notably, the rats treated with CSF administration exhibited diminished BPA accumulation in normal tissue compared to those treated with IV administration, alongside maintaining excellent overall health. Thus, CSF-based BPA administration holds promise as a novel drug delivery mechanism in BNCT.

Case report: Tenosynovial giant cell tumor.

Tenosynovial giant cell tumor (TGCT) is a rare type of tumor that originates from the synovium of joints and tendon sheaths. It is characterized by recurring genetic abnormalities, often involving the CSF1 gene. Common symptoms include pain and swelling, which are not specific to TGCT, so MRI and a pathological biopsy are needed for an accurate diagnosis. We report the case of a 45-year-old man who experienced painful swelling in his right hip for six months. Initially, this was diagnosed as Erdheim-Chester disease. However, whole exome sequencing (WES) and RNA-Sequencing revealed a CSF1::GAPDHP64 fusion, leading to a revised diagnosis of TGCT. The patient was treated with pegylated interferon and imatinib, which resulted in stable disease after three months. Single-cell transcriptome analysis identified seven distinct cell clusters, revealing that neoplastic cells expressing CSF1 attract macrophages. Analysis of ligand-receptor interactions showed significant communication between neoplastic cells and macrophages mediated by CSF1 and CSF1R. Our findings emphasize the importance of comprehensive molecular analysis in diagnosing and treating rare malignancies like TGCT.

Huang Lian Jie Du decoction attenuated colitis via suppressing the macrophage Csf1r/Src pathway and modulating gut microbiota.

Introduction: Ulcerative colitis, a subtype of chronic inflammatory bowel disease (IBD), is characterized by relapsing colonic inflammation and ulcers. The traditional Chinese herbal formulation Huang Lian Jie Du (HLJD) decoction is used clinically to treat diarrhea and colitis. However, the mechanisms associated with the effects of treatment remain unclear. This study aims to elucidate the molecular mechanistic effects of HLJD formulation on colitis. Methods: Chronic colitis in mice was induced by adding 1% dextran sulfate sodium (DSS) to their drinking water continuously for 8 weeks, and HLJD decoction at the doses of 2 and 4 g/kg was administered orally to mice daily from the second week until experimental endpoint. Stool consistency scores, blood stool scores, and body weights were recorded weekly. Disease activity index (DAI) was determined before necropsy, where colon tissues were collected for biochemical analyses. In addition, the fecal microbiome of treated mice was characterized using 16S rRNA amplicon sequencing. Results: HLJD decoction at doses of 2 and 4 g/kg relieved DSS-induced chronic colitis in mice by suppressing inflammation through compromised macrophage activity in colonic tissues associated with the colony-stimulating factor 1 receptor (Csf1r)/Src pathway. Furthermore, the HLJD formula could modify the gut microbiota profile by decreasing the abundance of Bacteroides, Odoribacter, Clostridium_sensu_stricto_1, and Parasutterella. In addition, close correlations between DAI, colon length, spleen weight, and gut microbiota were identified. Discussion: Our findings revealed that the HLJD formula attenuated DSS-induced chronic colitis by reducing inflammation via Csf1r/Src-mediated macrophage infiltration, as well as modulating the gut microbiota profile.

A protocol to isolate and characterize pure monocytes and generate monocyte-derived dendritic cells through FBS-Coated flasks.

This study explores methods to isolate high-pure monocytes and optimize the best growth factor concentration to generate monocytes-derived dendritic cells (mo-DCs), subset DC1, which is crucial in immune responses. Three protocols for monocyte isolation from peripheral blood mononuclear cells (PBMCs) were evaluated: three-hour incubation on FBS-coated flasks; an overnight incubation on FBS-coated flasks; and Magnetic Activated Cell Sorting (MACS). Additionally, five different concentrations of human recombinant granulocyte-macrophage colony-stimulating factor (hrGM-CSF) and human recombinant interleukin-4 (hrIL-4) were compared. We used Flow cytometry to assess the isolation, purification, and generation of pure monocytes characterized as CD14+, and expression of mo-DC classical markers (HLA-DR, CD80, CD83, and CD86). The obtained results show that monocytes isolated with the second method (overnight incubation) had the highest purity (P < 0.0001) but the lowest yield (P > 0.05), balancing purity and cost-effectiveness. A combination of hrGM-CSF and hrIL-4 at 400 U/mL produced the most favorable outcomes, leading to the highest rate of mo-DC generation (P < 0.05). Notably, this concentration resulted in increasing expression of HLA-DR, CD80, and CD86 surface markers in the generated DCs (P < 0.0001), with no changes in CD83 expression levels. In conclusion, this study offers valuable insights into selecting the optimal approach for monocyte isolation and mo-DC generation in various research contexts, providing a foundation for more effective immunological studies.

Efficacy of nebulized GM-CSF inhalation in preventing oral mucositis in patients undergoing hematopoietic stem cell transplantation: A retrospective study.

Objective: To study the efficacy of oxygen atomization inhalation of granulocyte-macrophage colony-stimulating factor (GM-CSF) for preventing oral mucositis in patients following hematopoietic stem cell transplantation. Methods: Data from patients who received hematopoietic stem cell transplantation and were treated with GM-CSF for the prevention/treatment of oral mucositis in our hospital from June 2021 to June 2023 were collected. The enrolled patients were divided into an observation group and a control group according to the use of GM-CSF. The WHO Mucositis Scale Assessment Criteria were utilized to evaluate the characteristics of patients with oral mucositis (OM) from the beginning of the pretreatment period until they were discharged from the hospital. The general data, preconditioning protocol, transplantation method, overall grade and duration of oral mucositis, pain score, nutritional score and number of days of parenteral nutrition use, oral mucosal infection status and antibiotic use intensity, the granulocyte and megakaryocyte reconstruction time, and adverse reaction reports of the patients were collected and summarized through the medical records system. Results: A total of 143 patients were included in this study, including 75 patients in the observation group. In the observation group, there were 36 males and 39 females aged 22-67 years. There were 45 patients who received autologous transplantation and 30 patients who received allogeneic transplantation. In terms of the disease distribution, there were 33 cases of leukemia, 24 cases of lymphoma, 11 cases of multiple myeloma, and 8 other cases (3 cases of aplastic anemia, 2 cases of myelodysplastic syndrome, 2 cases of myelofibrosis, 1 case of POEMS syndrome). There were 68 patients in the control group, including 33 males and 35 females; the control group patients were aged 25-74years. Forty-one patients received autologous transplantation, and 27 patients received allogeneic transplantation. The disease distribution included 29 cases of leukemia, 17 cases of lymphoma, 12 cases of multiple myeloma, and 7 other cases (3 cases of aplastic anemia, 2 cases of myelodysplastic syndrome, 1 case of myelofibrosis, 1 case of POEMS syndrome). There were no significant differences between the two groups concerning age, sex, disease distribution or the transplantation method (P > 0.05). In the observation group, 13 cases did not develop oral mucositis, and 32 cases developed oral mucositis (16 cases of Grade I, 14 cases of Grade II, 2 cases of Grade III, and 0 cases of Grade IV). In the control group, there were 5 cases without mucositis and 36 cases with oral mucositis (6 cases of Grade Ⅰ, 16 cases of Grade Ⅱ, 8 cases of Grade Ⅲ, and 6 cases of Grade Ⅳ), the difference was statistically significant (P < 0.05). The pain score and duration of mucositis in the observation group were significantly lower than those in the control group (P < 0.05). In addition, the oral infection rate, antibiotic use intensity, nutritional score, per capita number of days of parenteral nutrition use and hematopoietic reconstruction time in the observation group were significantly lower than those in the control group (P < 0.05). In the observation group, 8 patients did not develop oral mucositis, and 22 patients developed oral mucositis (13 cases of Grade I, 7 cases of Grade II, 1 case of Grade III, and 1 case of Grade IV). In the control group, 1 case did not develop mucositis, and 26 cases developed oral mucositis (3 cases of Grade Ⅰ, 10 cases of Grade Ⅱ, 9 cases of Grade Ⅲ, and 4 cases of Grade Ⅳ). The difference was statistically significant (P < 0.05). The pain score and duration of mucositis in the observation group were significantly lower than those in the control group (P < 0.05). In addition, the oral mucosal infection rate, antibiotic use intensity, nutritional score, per capita number of days of parenteral nutrition use and hematopoietic reconstruction time in the observation group were significantly lower than those in the control group (P < 0.05). No adverse reactions were reported in either group. Conclusion: In both autologous transplantation and allogeneic transplantation patients, GM-CSF atomized inhalation can improve the prevention and treatment of oral mucositis in stem cell transplantation patients, reduce the incidence of oral infection, reduce the intensity of antibiotic use and the number of days of parenteral nutrition use, and thus promote the process of hematopoietic reconstruction.

CSF1R Ligands Expressed by Murine Gliomas Promote M-MDSCs to Suppress CD8+ T Cells in a NOS-Dependent Manner.

Glioblastoma (GBM) is the most common malignant primary brain tumor, resulting in poor survival despite aggressive therapies. GBM is characterized by a highly heterogeneous and immunosuppressive tumor microenvironment (TME) made up predominantly of infiltrating peripheral immune cells. One significant immune cell type that contributes to glioma immune evasion is a population of immunosuppressive cells, termed myeloid-derived suppressor cells (MDSCs). Previous studies suggest that a subset of myeloid cells, expressing monocytic (M)-MDSC markers and dual expression of chemokine receptors CCR2 and CX3CR1, utilize CCR2 to infiltrate the TME. This study evaluated the mechanism of CCR2+/CX3CR1+ M-MDSC differentiation and T cell suppressive function in murine glioma models. We determined that bone marrow-derived CCR2+/CX3CR1+ cells adopt an immune suppressive cell phenotype when cultured with glioma-derived factors. Glioma-secreted CSF1R ligands M-CSF and IL-34 were identified as key drivers of M-MDSC differentiation while adenosine and iNOS pathways were implicated in the M-MDSC suppression of T cells. Mining a human GBM spatial RNAseq database revealed a variety of different pathways that M-MDSCs utilize to exert their suppressive function that is driven by complex niches within the microenvironment. These data provide a more comprehensive understanding of the mechanism of M-MDSCs in glioblastoma.

Gammaherpesvirus Infection Stimulates Lung Tumor-Promoting Inflammation.

Lung tumor-promoting environmental exposures and γherpesvirus infections are associated with Type 17 inflammation. To test the effect of γherpesvirus infection in promoting lung tumorigenesis, we infected mutant K-Ras-expressing (K-RasLA1) mice with the murine γherpesvirus MHV68 via oropharyngeal aspiration. After 7 weeks, the infected mice displayed a more than 2-fold increase in lung tumors relative to their K-RasLA1 uninfected littermates. Assessment of cytokines in the lung revealed that expression of Type 17 cytokines (Il-6, Cxcl1, Csf3) peaked at day 7 post-infection. These observations correlated with the post-infection appearance of known immune mediators of tumor promotion via IL-17A in the lungs of tumor-bearing mice. Surprisingly, Cd84, an immune cell marker mRNA, did not increase in MHV68-infected wild-type mice lacking lung tumors. Csf3 and Cxcl1 protein levels increased more in the lungs of infected K-RasLA1 mice relative to infected wild-type littermates. Flow cytometric and transcriptomic analyses indicated that the infected K-RasLA1 mice had increased Ly6Gdim/Ly6Chi immune cells in the lung relative to levels seen in uninfected control K-RasLA1 mice. Selective methylation of adenosines (m6A modification) in immune-cell-enriched mRNAs appeared to correlate with inflammatory infiltrates in the lung. These observations implicate γherpesvirus infection in lung tumor promotion and selective accumulation of immune cells in the lung that appears to be associated with m6A modification of mRNAs in those cells.

CSF1 is expressed by the intestinal epithelial cells to regulate Mφ macrophages and maintain epithelial homeostasis and is downregulated in neonates with necrotizing enterocolitis.

BACKGROUND: Colony stimulating factor 1 (CSF1) is generally expressed by immune cells in response to pro-inflammatory stimuli. The CSF1 receptor (CSFR) is activated by CSF1, and plays a key role in macrophage homeostasis. Furthermore, the CSF1R+ macrophages maintain homeostasis in the intestinal epithelium. The aim of this study was to explore the functions of CSF1-expressing and CSF1R+ macrophages in necrotizing enterocolitis (NEC), which commonly affects the ileum of neonates. METHODS: In-situ CSF1 expression in the intestines of neonates with NEC or intestinal atresia (n = 4 each) was detected by immunofluorescence staining. The CSF1 levels in the intestinal crypt-derived organoid cultures were measured by ELISA. Peripheral blood monocyte-derived Mφ macrophages were co-cultured with the organoids and stimulated with lipopolysaccharide (LPS) to mimic the inflamed state of the ileum in NEC patients. RESULTS: CSF1 was expressed in the intestinal epithelial cells of the fetal and neonatal samples, but suppressed in the NEC samples. Furthermore, CSF1 expression was downregulated in the intestinal crypt-derived organoids by LPS. CSF1R+ macrophages were detected near the intestinal crypts in the non-inflamed intestines but were absent in tissues obtained from pediatric NEC patients. Peripheral blood monocyte-derived macrophages promoted intestinal organoid proliferation in vitro following CSF1 stimulation. Finally, low concentrations of LPS slightly enhanced the proliferation of organoids co-cultured with the macrophages, whereas higher doses had a significant inhibitory effect. CONCLUSIONS: Intestinal epithelial cells express CSF1 to regulate the resident macrophages, maintain epithelial homeostasis, and resist infection. The abundant CSF1R+ macrophages in the fetal intestine may overexpress TNF-α upon activation of the TLR4/NF-κB pathway, resulting in epithelial damage and NEC induction.

Numerical analysis of the effect of Syringomyelia on cerebrospinal fluid dynamics.

Spinal cord enlargement (SCE) includes conditions such as Syringomyelia, tumors, and tumor-like cases of demyelination, edema, or inflammation. These conditions involve fluid-filled cysts, known as syrinx, or masses of tissue, referred to as tumors, which cause increased pressure within the spinal cord (SC) and obstruct cerebrospinal fluid (CSF) circulation. To assess the impact of SCE location and diameter, we constructed fifteen computational SC models, each featuring a SCE placed in one of five probable locations with 20 %, 40 %, and 60 % stenosis. Our objective was to investigate how the location, diameter, and length of the SCE influence CSF velocity pattern and to identify the most critical location in the SC associated with this condition. The results indicated a velocity increase of 0.5 cm/(s) near models with 60 % stenosis. Importantly, SCE located from T1 to T5 exhibit a more pronounced reduction, exceeding 6.5, in the Womersley number. Our finding suggests that this region is the most vulnerable for SCE formation due to its significant impact on fluid circulation. The identification of specific locations within the SC associated with heightened risk can contribute to an improved understanding, treatment and management of SCE.