Neuroprotective natural antibodies to assemblies of amyloidogenic peptides decrease with normal aging and advancing Alzheimer's disease

A number of distinct beta-amyloid (Abeta) variants or multimers have been implicated in Alzheimer's disease (AD), and antibodies recognizing such peptides are in clinical trials. Humans have natural Abeta-specific antibodies, but their diversity, abundance, and function in the general population remain largely unknown. Here, we demonstrate with peptide microarrays the presence of natural antibodies against known toxic Abeta and amyloidogenic non-Abeta species in plasma samples and cerebrospinal fluid of AD patients and healthy controls aged 21-89 years. Antibody reactivity was most prominent against oligomeric assemblies of Abeta and pyroglutamate or oxidized residues, and IgGs specific for oligomeric preparations of Abeta1-42 in particular declined with age and advancing AD. Most individuals showed unexpected antibody reactivities against peptides unique to autosomal dominant forms of dementia (mutant Abeta, ABri, ADan) and IgGs isolated from plasma of AD patients or healthy controls protected primary neurons from Abeta toxicity. Aged vervets showed similar patterns of plasma IgG antibodies against amyloid peptides, and after immunization with Abeta the monkeys developed high titers not only against Abeta peptides but also against ABri and ADan peptides. Our findings support the concept of conformation-specific, cross-reactive antibodies that may protect against amyloidogenic toxic peptides. If a therapeutic benefit of Abeta antibodies can be confirmed in AD patients, stimulating the production of such neuroprotective antibodies or passively administering them to the elderly population may provide a preventive measure toward AD

Network-driven plasma proteomics expose molecular changes in the Alzheimer’s brain

Background Biological pathways that significantly contribute to sporadic Alzheimer’s disease are largely unknown and cannot be observed directly. Cognitive symptoms appear only decades after the molecular disease onset, further complicating analyses. As a consequence, molecular research is often restricted to late-stage post-mortem studies of brain tissue. However, the disease process is expected to trigger numerous cellular signaling pathways and modulate the local and systemic environment, and resulting changes in secreted signaling molecules carry information about otherwise inaccessible pathological processes. Results To access this information we probed relative levels of close to 600 secreted signaling proteins from patients’ blood samples using antibody microarrays and mapped disease-specific molecular networks. Using these networks as seeds we then employed independent genome and transcriptome data sets to corroborate potential pathogenic pathways. Conclusions We identified Growth-Differentiation Factor (GDF) signaling as a novel Alzheimer’s disease-relevant pathway supported by in vivo and in vitro follow-up experiments, demonstrating the existence of a highly informative link between cellular pathology and changes in circulatory signaling proteins

Essential role of CCL21 in establishment of central self-tolerance in T cells.

The chemokine receptor CCR7 directs T cell relocation into and within lymphoid organs, including the migration of developing thymocytes into the thymic medulla. However, how three functional CCR7 ligands in mouse, CCL19, CCL21Ser, and CCL21Leu, divide their roles in immune organs is unclear. By producing mice specifically deficient in CCL21Ser, we show that CCL21Ser is essential for the accumulation of positively selected thymocytes in the thymic medulla. CCL21Ser-deficient mice were impaired in the medullary deletion of self-reactive thymocytes and developed autoimmune dacryoadenitis. T cell accumulation in the lymph nodes was also defective. These results indicate a nonredundant role of CCL21Ser in the establishment of self-tolerance in T cells in the thymic medulla, and reveal a functional inequality among CCR7 ligands in vivo

How to read a next-generation sequencing report-what oncologists need to know.

Next-generation sequencing (NGS) of tumor cell-derived DNA/RNA to screen for targetable genomic alterations is now widely available and has become part of routine practice in oncology. NGS testing strategies depend on cancer type, disease stage and the impact of results on treatment selection. The European Society for Medical Oncology (ESMO) has recently published recommendations for the use of NGS in patients with advanced cancer. We complement the ESMO recommendations with a practical review of how oncologists should read and interpret NGS reports. A concise and straightforward NGS report contains details of the tumor sample, the technology used and highlights not only the most important and potentially actionable results, but also other pathogenic alterations detected. Variants of unknown significance should also be listed. Interpretation of NGS reports should be a joint effort between molecular pathologists, tumor biologists and clinicians. Rather than relying and acting on the information provided by the NGS report, oncologists need to obtain a basic level of understanding to read and interpret NGS results. Comprehensive annotated databases are available for clinicians to review the information detailed in the NGS report. Molecular tumor boards do not only stimulate debate and exchange, but may also help to interpret challenging reports and to ensure continuing medical education

Improving the turnaround time of molecular profiling for advanced non-small cell lung cancer: Outcome of a new algorithm integrating multiple approaches

BACKGROUND Molecular tumor profiling to identify oncogenic drivers and actionable mutations has a profound impact on how lung cancer is treated. Especially in the subgroup of non-small cell lung cancer (NSCLC), molecular testing for certain mutations is crucial in daily clinical practice and is recommended by international guidelines. To date, a standardized approach to identify druggable genetic alterations are lacking. We have developed and implemented a new diagnostic algorithm to harmonize the molecular testing of NSCLC. PATIENTS AND METHODS In this retrospective analysis, we reviewed 119 patients diagnosed with NSCLC at the University Hospital Zurich. Tumor samples were analyzed using our standardized diagnostic algorithm: After the histological diagnosis was made, tissue samples were further analyzed by immunohistochemical stainings as well as the real-time PCR test Idylla™. Extracted DNA was further utilized for comprehensive genomic profiling (FoundationOne®CDx, F1CDx). RESULTS Out of the 119 patients were included in this study, 100 patients were diagnosed with non-squamous NSCLC (nsqNSCLC) and 19 with squamous NSCLC (sqNSCLC). The samples from the nsqNSCLC patients underwent testing by Idylla™ and were evaluated by immunohistochemistry (IHC). F1CDx analysis was run on 67 samples and 46 potentially actionable genomic alterations were detected. Ten patients received the indicated targeted treatment. The median time to test results was 4 days for the Idylla test, 5 days for IHC and 13 days for the F1CDx. CONCLUSION In patients with NSCLC, the implementation of a standardized molecular testing algorithm provided information on predictive markers for NSCLC within a few working days. The implementation of broader genomic profiling led to the identification of actionable targets, which would otherwise not have been discovered

Alzheimer's Risk Gene TREM2 Determines Functional Properties of New Type of Human iPSC-Derived Microglia

Microglia are key in the homeostatic well-being of the brain and microglial dysfunction has been implicated in neurodegenerative disorders such as Alzheimer's disease (AD). Due to the many limitations to study microglia in situ or isolated for large scale drug discovery applications, there is a high need to develop robust and scalable human cellular models of microglia with reliable translatability to the disease. Here, we describe the generation of microglia-like cells from human induced pluripotent stem cells (iPSC) with distinct phenotypes for mechanistic studies in AD. We started out from an established differentiation protocol to generate primitive macrophage precursors mimicking the yolk sac ontogeny of microglia. Subsequently, we tested 36 differentiation conditions for the cells in monoculture where we exposed them to various combinations of media, morphogens, and extracellular matrices. The optimized protocol generated robustly ramified cells expressing key microglial markers. Bulk mRNA sequencing expression profiles revealed that compared to cells obtained in co-culture with neurons, microglia-like cells derived from a monoculture condition upregulate mRNA levels for Triggering Receptor Expressed On Myeloid Cells 2 (TREM2), which is reminiscent to the previously described disease-associated microglia. TREM2 is a risk gene for AD and an important regulator of microglia. The regulatory function of TREM2 in these cells was confirmed by comparing wild type with isogenic TREM2 knock-out iPSC microglia. The TREM2-deficient cells presented with stronger increase in free cytosolic calcium upon stimulation with ATP and ADP, as well as stronger migration towards complement C5a, compared to TREM2 expressing cells. The functional differences were associated with gene expression modulation of key regulators of microglia. In conclusion, we have established and validated a work stream to generate functional human iPSC-derived microglia-like cells by applying a directed and neuronal co-culture independent differentiation towards functional phenotypes in the context of AD. These cells can now be applied to study AD-related disease settings and to perform compound screening and testing for drug discoverySG was supported by the Roche Postdoctoral Fellowship (RPF) program and IP by the Roche Internships for Scientific Exchange (RiSE) progra

Unravelling homologous recombination repair deficiency and therapeutic opportunities in soft tissue and bone sarcoma.

Defects in homologous recombination repair (HRR) in tumors correlate with poor prognosis and metastases development. Determining HRR deficiency (HRD) is of major clinical relevance as it is associated with therapeutic vulnerabilities and remains poorly investigated in sarcoma. Here, we show that specific sarcoma entities exhibit high levels of genomic instability signatures and molecular alterations in HRR genes, while harboring a complex pattern of chromosomal instability. Furthermore, sarcomas carrying HRDness traits exhibit a distinct SARC-HRD transcriptional signature that predicts PARP inhibitor sensitivity in patient-derived sarcoma cells. Concomitantly, HRD$^{high}$ sarcoma cells lack RAD51 nuclear foci formation upon DNA damage, further evidencing defects in HRR. We further identify the WEE1 kinase as a therapeutic vulnerability for sarcomas with HRDness and demonstrate the clinical benefit of combining DNA damaging agents and inhibitors of DNA repair pathways ex vivo and in the clinic. In summary, we provide a personalized oncological approach to treat sarcoma patients successfully

Global Health: A Successful Context for Precollege Training and Advocacy

Despite a flourishing biomedical and global health industry [1] too few of Washington state's precollege students are aware of this growing sector and emerging ideas on bacteria, fungi, parasites and viruses. Against the backdrop of numerous reports regarding declining precollege student interest in science [2], a precollege program was envisioned at Seattle Biomedical Research Institute (as of 2010, Seattle BioMed) to increase youth engagement in biomedical research and global health, increase community interest in infectious diseases and mobilize a future biomedical workforce. Since 2005, 169 rising high school juniors have participated in the BioQuest Academy precollege immersion program at Seattle BioMed. Assembling in groups of 12, students conduct laboratory experiments (e.g., anopheline mosquito dissection, gene expression informed tuberculosis drug design and optimizing HIV immunization strategies) related to global health alongside practicing scientific mentors, all within the footprint the institute. Laudable short-term impacts of the program include positive influences on student interest in global health (as seen in the students' subsequent school projects and their participation in Seattle BioMed community events), biomedical careers and graduate school (e.g., 16.9% of teens departing 2008–2009 Academy report revised goals of attaining a doctorate rather than a baccalaureate diploma). Long-term, 97% of alumni (2005–2008) are attending postsecondary schools throughout North America; eight graduates have already published scientific articles in peer-reviewed journals and/or presented their scientific data at national and international meetings, and 26 have been retained by Seattle BioMed researchers as compensated technicians and interns. Providing precollege students with structured access to practicing scientists and authentic research environments within the context of advancing global health has been a robust means of both building a future pool of talented leaders and engaged citizenry and increasing the visibility of health disparities within the community

Combinatorial Guidance by CCR7 Ligands for T Lymphocytes Migration in Co-Existing Chemokine Fields

Chemokines mediate the trafficking and positioning of lymphocytes in lymphoid tissues that is crucial for immune surveillance and immune responses. In particular, a CCR7 ligand, CCL21, plays important roles in recruiting T cells to secondary lymphoid tissues (SLT). Furthermore, CCL21 together with another CCR7 ligand, CCL19, direct the navigation and compartmentation of T cells within SLT. However, the distinct roles of these two chemokines for regulating cell trafficking and positioning are not clear. In this study, we explore the effect of co-existing CCL19 and CCL21 concentration fields on guiding T cell migration. Using microfluidic devices that can configure single and superimposed chemokine fields we show that under physiological gradient conditions, human peripheral blood T cells chemotax to CCL21 but not CCL19. Furthermore, T cells migrate away from the CCL19 gradient in a uniform background of CCL21. This repulsive migratory response is predicted by mathematical modeling based on the competition of CCL19 and CCL21 for CCR7 signaling and the differential ability of the two chemokines for desensitizing CCR7. These results suggest a new combinatorial guiding mechanism by CCL19 and CCL21 for the migration and trafficking of CCR7 expressing leukocytes

Safety, Tolerability, and Potential Clinical Activity of a Glucocorticoid-Induced TNF Receptor-Related Protein Agonist Alone or in Combination with Nivolumab for Patients with Advanced Solid Tumors : A Phase 1/2a Dose-Escalation and Cohort-Expansion Clinical Trial

Importance: Multiple immunostimulatory agonist antibodies have been clinically tested in solid tumors to evaluate the role of targeting glucocorticoid-induced tumor necrosis factor (TNF) receptor-related protein in anticancer treatments. Objective: To evaluate the safety and activity of the fully human glucocorticoid-induced TNF receptor-related protein agonist IgG1 monoclonal antibody BMS-986156 with or without nivolumab in patients with advanced solid tumors. Design, Setting, and Participants: This global, open-label, phase 1/2a study of BMS-986156 with or without nivolumab enrolled 292 patients 18 years or older with advanced solid tumors and an Eastern Cooperative Oncology Group performance status of 1 or less. Prior checkpoint inhibitor therapy was allowed. Monotherapy and combination dose-escalation cohorts ran concurrently to guide expansion doses beginning October 16, 2015; the study is ongoing. Interventions: The protein agonist BMS-986156 was administered intravenously at a dose of 10, 30, 100, 240, or 800 mg every 2 weeks as monotherapy, and in the combination group 30, 100, 240, or 800 mg plus 240 mg of nivolumab every 2 weeks; same-dose cohorts were pooled for analysis. One cohort also received 480 mg of BMS-986156 plus 480 mg of nivolumab every 4 weeks. Main Outcomes and Measures: The primary end points were safety, tolerability, and dose-limiting toxic effects. Additional end points included antitumor activity per Response Evaluation Criteria in Solid Tumors, version 1.1, and exploratory biomarker analyses. Results: With a follow-up range of 1.4 to 101.7 weeks (follow-up ongoing), 34 patients (16 women and 18 men; median age, 56.6 years [range, 28-75 years]) received monotherapy (4 patients completed initial treatment), and 258 patients (140 women and 118 men; median age, 60 years [range, 21-87 years]) received combination therapy (65 patients completed initial treatment). No grade 3 to 5 treatment-related adverse events occurred with BMS-986156 monotherapy; grade 3 to 4 treatment-related adverse events occurred in 24 patients (9.3%) receiving BMS-986156 plus nivolumab, with no grade 5 treatment-related adverse events. One dose-limiting toxic effect (grade 4 elevated creatine phosphokinase levels) occurred in a patient receiving 800 mg of BMS-986156 plus 240 mg of nivolumab every 2 weeks; BMS-986156 with or without nivolumab exhibited linear pharmacokinetics with dose-related increase after a single dose. Peripheral T-cell and natural killer-cell proliferation increased after administration of BMS-986156 with or without nivolumab. No consistent and significant modulation of intratumoral CD8+ T cells and FoxP3+ regulatory T cells was observed. No responses were seen with BMS-986156 alone; objective response rates ranged from 0% to 11.1% (1 of 9) across combination therapy cohorts, with a few responses observed in patients previously treated with anti-programmed death receptor (ligand) 1 therapy. Conclusions and Relevance: Based on this cohort, BMS-986156 appears to have had a manageable safety profile, and BMS-986156 plus nivolumab demonstrated safety and efficacy comparable to historical data reported for nivolumab monotherapy