16 research outputs found
Small heat shock proteins are induced during multiple sclerosis lesion development in white but not grey matter
INTRODUCTION: The important protective role of small heat-shock proteins (HSPs) in regulating cellular survival and migration, counteracting protein aggregation, preventing apoptosis, and regulating inflammation in the central nervous system is now well-recognized. Yet, their role in the neuroinflammatory disorder multiple sclerosis (MS) is largely undocumented. With the exception of alpha B-crystallin (HSPB5), little is known about the roles of small HSPs in disease. RESULTS: Here, we examined the expression of four small HSPs during lesion development in MS, focussing on their cellular distribution, and regional differences between white matter (WM) and grey matter (GM). It is well known that MS lesions in these areas differ markedly in their pathology, with substantially more intense blood-brain barrier damage, leukocyte infiltration and microglial activation typifying WM but not GM lesions. We analysed transcript levels and protein distribution profiles for HSPB1, HSPB6, HSPB8 and HSPB11 in MS lesions at different stages, comparing them with normal-appearing brain tissue from MS patients and non-neurological controls. During active stages of demyelination in WM, and especially the centre of chronic active MS lesions, we found significantly increased expression of HSPB1, HSPB6 and HSPB8, but not HSPB11. When induced, small HSPs were exclusively found in astrocytes but not in oligodendrocytes, microglia or neurons. Surprisingly, while the numbers of astrocytes displaying high expression of small HSPs were markedly increased in actively demyelinating lesions in WM, no such induction was observed in GM lesions. This difference was particularly obvious in leukocortical lesions covering both WM and GM areas. CONCLUSIONS: Since induction of small HSPs in astrocytes is apparently a secondary response to damage, their differential expression between WM and GM likely reflects differences in mediators that accompany demyelination in either WM or GM during MS. Our findings also suggest that during MS, cortical structures fail to benefit from the protective actions of small HSPs. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s40478-015-0267-2) contains supplementary material, which is available to authorized users
Neoadjuvant immunotherapy with nivolumab and ipilimumab induces major pathological responses in patients with head and neck squamous cell carcinoma
Surgery for locoregionally advanced head and neck squamous cell carcinoma (HNSCC) results in 30‒50% five-year overall survival. In IMCISION (NCT03003637), a non-randomized phase Ib/IIa trial, 32 HNSCC patients are treated with 2 doses (in weeks 1 and 3) of immune checkpoint blockade (ICB) using nivolumab (NIVO MONO, n = 6, phase Ib arm A) or nivolumab plus a single dose of ipilimumab (COMBO, n = 26, 6 in phase Ib arm B, and 20 in phase IIa) prior to surgery. Primary endpoints are feasibility to resect no later than week 6 (phase Ib) and primary tumor pathological response (phase IIa). Surgery is not delayed or suspended for any patient in phase Ib, meeting the primary endpoint. Grade 3‒4 immune-related adverse events are seen in 2 of 6 (33%) NIVO MONO and 10 of 26 (38%) total COMBO patients. Pathological response, defined as the %-change in primary tumor viable tumor cell percentage from baseline biopsy to on-treatment resection, is evaluable in 17/20 phase IIa patients and 29/32 total trial patients (6/6 NIVO MONO, 23/26 COMBO). We observe a major pathological response (MPR, 90‒100% response) in 35% of patients after COMBO ICB, both in phase IIa (6/17) and in the whole trial (8/23), meeting the phase IIa primary endpoint threshold of 10%. NIVO MONO’s MPR rate is 17% (1/6). None of the MPR patients develop recurrent HSNCC during 24.0 months median postsurgical follow-up. FDG-PET-based total lesion glycolysis identifies MPR patients prior to surgery. A baseline AID/APOBEC-associated mutational profile and an on-treatment decrease in hypoxia RNA signature are observed in MPR patients. Our data indicate that neoadjuvant COMBO ICB is feasible and encouragingly efficacious in HNSCC
Exploring Data Provenance in Handwritten Text Recognition Infrastructure: Sharing and Reusing Ground Truth Data, Referencing Models, and Acknowledging Contributions. Starting the Conversation on How We Could Get It Done
This paper discusses best practices for sharing and reusing Ground Truth in Handwritten Text Recognition infrastructures, as well as ways to reference and acknowledge contributions to the creation and enrichment of data within these systems. We discuss how one can place Ground Truth data in a repository and, subsequently, inform others through HTR-United. Furthermore, we want to suggest appropriate citation methods for ATR data, models, and contributions made by volunteers. Moreover, when using digitised sources (digital facsimiles), it becomes increasingly important to distinguish between the physical object and the digital collection. These topics all relate to the proper acknowledgement of labour put into digitising, transcribing, and sharing Ground Truth HTR data. This also points to broader issues surrounding the use of machine learning in archival and library contexts, and how the community should begin to acknowledge and record both contributions and data provenance
Exploring data provenance in handwritten text recognition infrastructure:Sharing and reusing ground truth data, referencing models, and acknowledging contributions. Starting the conversation on how we could get it done
This paper discusses best practices for sharing and reusing Ground Truth in Handwritten Text Recognition infrastructures, and ways to reference and acknowledge contributions to the creation and enrichment of data within these Machine Learning systems. We discuss how one can publish Ground Truth data in a repository and, subsequently, inform others. Furthermore, we suggest appropriate citation methods for HTR data, models, and contributions made by volunteers. Moreover, when using digitised sources (digital facsimiles), it becomes increasingly important to distinguish between the physical object and the digital collection. These topics all relate to the proper acknowledgement of labour put into digitising, transcribing, and sharing Ground Truth HTR data. This also points to broader issues surrounding the use of Machine Learning in archival and library contexts, and how the community should begin toacknowledge and record both contributions and data provenance
The genetic architecture of the human cerebral cortex
The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder
Oligodendrocyte-microglia cross-talk in the central nervous system
Communication between the immune system and the central nervous system (CNS) is exemplified by cross-talk between glia and neurons shown to be essential for maintaining homeostasis. While microglia are actively modulated by neurons in the healthy brain, little is known about the cross-talk between oligodendrocytes and microglia. Oligodendrocytes, the myelin-forming cells in the CNS, are essential for the propagation of action potentials along axons, and additionally serve to support neurons by producing neurotrophic factors. In demyelinating diseases such as multiple sclerosis, oligodendrocytes are thought to be the victims. Here, we review evidence that oligodendrocytes also have strong immune functions, express a wide variety of innate immune receptors, and produce and respond to chemokines and cytokines that modulate immune responses in the CNS. We also review evidence that during stress events in the brain, oligodendrocytes can trigger a cascade of protective and regenerative responses, in addition to responses that elicit progressive neurodegeneration. Knowledge of the cross-talk between microglia and oligodendrocytes may continue to uncover novel pathways of immune regulation in the brain that could be further exploited to control neuroinflammation and degeneration
Role of Delay Between Injury and Surgery on the Outcomes of Rotator Cuff Repair: A Systematic Review and Meta-analysis
Background: Outcomes of rotator cuff repair (RCR) are influenced by several well-described factors, but the role of delay from injury to surgery on the outcomes is not clear. Purpose: To assess the role of delay to surgery on the outcomes of RCR in the literature. Study Design: Systematic review with meta-analysis; Level of evidence, 4. Methods: PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed. All studies assessing outcomes after RCR—either retear rates or patient-reported outcome measures (PROMs)—and reporting delay to surgery were identified through June 2021 in PubMed, Embase, and Cochrane. Inclusion criteria consisted of traumatic injuries, mean age 3 months after injury did not have significantly higher retear rates (OR, 1.1 [95% CI, 0.5 to 3.1]; P =.700), lower Constant-Murley score (MD, −6.2 [95% CI, −16.4 to 4.1]; P =.240), or lower ASES score (American Shoulder and Elbow Surgeons; MD, –12.9 [95% CI, −26.0 to −0.2]; P =.050) compared with those having surgery within 3 months. Similarly, delaying surgery for 6 months did not result in higher retear rates (OR, 1.7 [95% CI, 0.8 to 3.7]; P =.190) or lower PROMs. Delaying surgery for 1 year, however, led to an increased likelihood of retear when compared with <1 year (OR, 2.9 [95% CI, 2.1 to 4.0]; P <.001), and this was similar for the 2-year cutoff (OR, 5.9 [95% CI, 1.1 to 32.1]; P =.040). It was also noted that patients with an intact cuff at follow-up had a mean 3.9 months’ shorter time from injury to surgery than patients with retear (95% CI, 1.0-6.8 months; P =.009). Conclusion: This systematic review with meta-analysis found that delaying rotator cuff surgery for 3 to 6 months did not lead to higher retear rates or inferior PROMs as compared with undergoing earlier surgery. However, delaying surgery for ≥1 year clearly resulted in higher retear rates after RCR. This study is limited by relying on retrospective studies, and larger prospective studies are needed to confirm these findings. Registration: CRD42021240720 (PROSPERO)
Demyelination during multiple sclerosis is associated with combined activation of microglia/macrophages by IFN-gamma and alpha B-crystallin
Activated microglia and macrophages play a key role in driving demyelination during multiple sclerosis (MS), but the factors responsible for their activation remain poorly understood. Here, we present evidence for a dual-trigger role of IFN-gamma and alpha B-crystallin (HSPB5) in this context. In MS-affected brain tissue, accumulation of the molecular chaperone HSPB5 by stressed oligodendrocytes is a frequent event. We have shown before that this triggers a TLR2-mediated protective response in surrounding microglia, the molecular signature of which is widespread in normal-appearing brain tissue during MS. Here, we show that IFN-gamma, which can be released by infiltrated T cells, changes the protective response of microglia and macrophages to HSPB5 into a robust pro-inflammatory classical response. Exposure of cultured microglia and macrophages to IFN-gamma abrogated subsequent IL-10 induction by HSPB5, and strongly promoted HSPB5-triggered release of TNF-alpha, IL-6, IL-12, IL-1 beta and reactive oxygen and nitrogen species. In addition, high levels of CXCL9, CXCL10, CXL11, several guanylate-binding proteins and the ubiquitin-like protein FAT10 were induced by combined activation with IFN-gamma and HSPB5. As immunohistochemical markers for microglia and macrophages exposed to both IFN-gamma and HSPB5, these latter factors were found to be selectively expressed in inflammatory infiltrates in areas of demyelination during MS. In contrast, they were absent from activated microglia in normal-appearing brain tissue. Together, our data suggest that inflammatory demyelination during MS is selectively associated with IFN-gamma-induced re-programming of an otherwise protective response of microglia and macrophages to the endogenous TLR2 agonist HSPB5