107 research outputs found
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Speaking out about gender imbalance in invited speakers improves diversity.
Omissions of qualified women scientists from major meeting programs continue to occur despite a surge in articles indicating persistent gender-discriminatory practices in hiring and promotion, and calls for gender balance in conference organizing committees
Hieroglyph: Hierarchical Glia Graph Skeletonization and Matching
Automatic 3D reconstruction of glia morphology is a powerful tool necessary
for investigating the role of microglia in neurological disorders in the
central nervous system. Current glia skeleton reconstruction techniques fail to
capture an accurate tracing of the processes over time, useful for the study of
the microglia motility and morphology in the brain during healthy and diseased
states. We propose Hieroglyph, a fully automatic temporal 3D skeleton
reconstruction algorithm for glia imaged via 3D multiphoton microscopy.
Hieroglyph yielded a 21% performance increase compared to state of the art
automatic skeleton reconstruction methods and outperforms the state of the art
in different measures of consistency on datasets of 3D images of microglia. The
results from this method provide a 3D graph and digital reconstruction of glia
useful for a myriad of morphological analyses that could impact studies in
brain immunology and disease.Comment: submitted to IEEE International Conference on Image Processing, 201
RIPK3-Dependent Recruitment of Low-Inflammatory Myeloid Cells Does Not Protect from Systemic Salmonella Infection
ABSTRACT Regulated macrophage death has emerged as an important mechanism to defend against intracellular pathogens. However, the importance and consequences of macrophage death during bacterial infection are poorly resolved. This is especially true for the recently described RIPK3-dependent lytic cell death, termed necroptosis. Salmonella enterica serovar Typhimurium is an intracellular pathogen that precisely regulates virulence expression within macrophages to evade and manipulate immune responses, which is a key factor in its ability to cause severe systemic infections. We combined genetic and pharmacological approaches to examine the importance of RIPK3 for S. Typhimurium-induced macrophage death using conditions that recapitulate bacterial gene expression during systemic infection in vivo. Our findings indicate that noninvasive S. Typhimurium does not naturally induce macrophage necroptosis but does so in the presence of pan-caspase inhibition. Moreover, our data suggest that RIPK3 induction (following caspase inhibition) does not impact host survival following S. Typhimurium infection, which differs from previous findings based on inert lipopolysaccharide (LPS) injections. Finally, although necroptosis is typically characterized as highly inflammatory, our data suggest that RIPK3 skews the peritoneal myeloid population away from an inflammatory profile to that of a classically noninflammatory profile. Collectively, these data improve our understanding of S. Typhimurium-macrophage interactions, highlight the possibility that purified bacterial components may not accurately recapitulate the complexity of host-pathogen interactions, and reveal a potential and unexpected role for RIPK3 in resolving inflammation. IMPORTANCE Macrophages employ multiple strategies to limit pathogen infection. For example, macrophages may undergo regulated cell death, including RIPK3-dependent necroptosis, as a means of combatting intracellular bacterial pathogens. However, bacteria have evolved mechanisms to evade or exploit immune responses. Salmonella is an intracellular pathogen that avoids and manipulates immune detection within macrophages. We examined the contribution of RIPK3 to Salmonella-induced macrophage death. Our findings indicate that noninvasive Salmonella does not naturally induce necroptosis, but it does so when caspases are inhibited. Moreover, RIPK3 induction (following caspase inhibition) does not impact host survival following Salmonella systemic infection. Finally, our data show that RIPK3 induction results in recruitment of low-inflammatory myeloid cells, which was unexpected, as necroptosis is typically described as highly inflammatory. Collectively, these data improve our understanding of pathogen-macrophage interactions, including outcomes of regulated cell death during infection in vivo, and reveal a potential new role for RIPK3 in resolving inflammation
Effectiveness of Immune Checkpoint Inhibition vs Chemotherapy in Combination With Radiation Therapy Among Patients With Non–Small Cell Lung Cancer and Brain Metastasis Undergoing Neurosurgical Resection
Importance: Patients with brain metastases from non-small cell lung cancer (NSCLC) have regularly been excluded from prospective clinical trials that include therapy with immune checkpoint inhibitors (ICIs). Clinical data demonstrating benefit with ICIs, specifically following neurosurgical brain metastasis resection, are scarce.
Objective: To evaluate and compare the association of radiation therapy with ICIs vs classic therapy involving radiation therapy and chemotherapy regarding overall survival in a cohort of patients who underwent NSCLC brain metastasis resection.
Design, setting and participants: This single-center 1:1 propensity-matched comparative effectiveness study at the largest neurosurgical clinic in Germany included individuals who had undergone craniotomy with brain metastasis resection from January 2010 to December 2021 with histologically confirmed NSCLC. Of 1690 patients with lung cancer and brain metastasis, 480 were included in the study. Key exclusion criteria were small-cell lung cancer, lack of tumor cells by means of histopathological analysis on brain metastasis resection, and patients who underwent biopsy without tumor resection. The association of overall survival with treatment with radiation therapy and chemotherapy vs radiation therapy and ICI was evaluated.
Exposures: Radiation therapy and chemotherapy vs radiation therapy and ICI following craniotomy and microsurgical brain metastasis resection.
Main outcomes and measures: Median overall survival.
Results: From the whole cohort of patients with NSCLC (N = 384). 215 (56%) were male and 169 (44%) were female. The median (IQR) age was 64 (57-72) years. The 2 cohorts of interest included 108 patients (31%) with radiation therapy and chemotherapy and 63 patients (16%) with radiation therapy and ICI following neurosurgical metastasis removal (before matching). Median (IQR) follow-up time for the total cohort was 47.9 (28.2-70.1) months with 89 patients (23%) being censored and 295 (77%) dead at the end of follow-up in December 2021. After covariate equalization using propensity score matching (62 patients per group), patients receiving radiation therapy and chemotherapy after neurosurgery had significantly lower overall survival (11.8 months; 95% CI; 9.1-15.2) compared with patients with radiation therapy and ICIs (23.0 months; 95% CI; 20.3-53.8) (P < .001).
Conclusions and relevance: Patients with NSCLC brain metastases undergoing neurosurgical resection had longer overall survival when treated with radiation therapy and ICIs following neurosurgery compared with those receiving platinum-based chemotherapy and radiation. Radiation and systemic immunotherapy should be regularly evaluated as a treatment option for these patients
miR-29b and miR-198 overexpression in CD8<sup>+</sup> T cells of renal cell carcinoma patients down-modulates JAK3 and MCL-1 leading to immune dysfunction
Background: Mammalian microRNAs (miR) regulate the expression of genes relevant for the development of adaptive and innate immunity against cancer. Since T cell dysfunction has previously been reported in patients with renal cell carcinoma (RCC; clear cell type), we aimed to analyze these immune cells for genetic and protein differences when compared to normal donor T cells freshly after isolation and 35 days after in vitro stimulation (IVS) with HLA-matched RCC tumor cells. Methods: We investigated gene expression profiles of tumor-reactive CD8+ T cells obtained from RCC patient and compared with their HLA-matched healthy sibling donors using a microarray approach. In addition, miRNAs analysis was performed in a validation cohort of peripheral blood CD8+ T cells from 25 RCC patients compared to 15 healthy volunteers. Results: We observed that CD8+ T cells from RCC patients expressed reduced levels of anti-apoptotic and proliferation-associated gene products when compared with normal donor T cells both pre- and post-IVS. In particular, JAK3 and MCL-1 were down-regulated in patient CD8+ T cells versus their normal counterparts, likely due to defective suppressor activity of miR-29b and miR-198 in RCC CD8+ T cells. Indeed, specific inhibition of miR-29b or miR-198 in peripheral blood mononuclear cells (PBMCs) isolated from RCC patients, resulted in the up-regulation of JAK3 and MCL-1 proteins and significant improvement of cell survival in vitro. Conclusions: Our results suggest that miR-29b and miR-198 dysregulation in RCC patient CD8+ T cells is associated with dysfunctional immunity and foreshadow the development of miR-targeted therapeutics to correct such T cell defects in vivo
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Editorial: Immunotherapy for Tumor in the Brain: Insights From—and For—Other Tumor Sites
Tumor immunotherapy has now shown its promise for many, its disappointments and failings for others. Going forward, brain tumor patients can both benefit and contribute.Tumor immunotherapy is steadily progressing. As experience accumulates, it is important to consider its generality. The reviews herein emphasize the brain’s place among other tumor sites. Two major topics are addressed.THE SITE: WHAT CAN WE EXPECT FROM IMMUNOTHERAPY WHEN THE TARGET IS IN THE BRAIN?Experience with immunotherapy for different targets in the brain, including tumor and also pathogens, is reviewed. Long-standing assumptions are confronted. The potential for beneficial responses is stressed.BRAIN TUMOR IMMUNOTHERAPY: WHAT HAVE WE LEARNED SO FAR?Clinical experience with brain tumor immunotherapy, from a variety of centers, is reviewed. Primary tumors, emphasizing glioblastoma, and brain metastases are each considered
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