Relapses in patients treated with fingolimod after previous exposure to natalizumab.

In post hoc analyses of an open-label, phase 3b study (FIRST), relapse rates during 4 months of fingolimod therapy were compared in patients with and without previous natalizumab exposure. Reductions in the proportion of patients experiencing relapses and annualized relapse rates (ARRs) from years 1 and 1-2 pre-study were evident between months 1 and 2 of fingolimod treatment, and were most pronounced in natalizumab-naïve patients and those who discontinued natalizumab >6 months pre-study. Patients who discontinued natalizumab 3-6 months pre-study had a peak ARR during month 1 of fingolimod treatment, followed by a decrease during months 2-4. These data indicate that fingolimod has the potential to reduce disease reactivation but that timing of treatment initiation may be critical for achieving an optimal effect.

Five-year results from a phase 2 study of oral fingolimod in relapsing multiple sclerosis.

We present here results at 60 months (M), from the extension component of a phase 2, randomized, placebo-controlled, double-blind, six-month study evaluating oral fingolimod (1.25 mg or 5 mg daily) in relapsing multiple sclerosis. Placebo patients from the core study were re-randomized to fingolimod 1.25 mg or 5 mg in the extension. All patients received 1.25 mg fingolimod after the M24 visit. A total of 140/281 (49.8%) patients completed M60. Fingolimod treatment was associated with a low annualized relapse rate (0.2 relapses/ year), low MRI activity, and a modest rate of disability progression in those treated for five years. No new safety issues were reported.

[Genetic etiology of chronic inflammatory bowel disease]. / Genetische Ätiologie bei chronisch-entzündlichen Darmerkrankungen.

Crohn's disease and ulcerative colitis are the two main forms of inflammatory bowel disease. Inflammatory bowel diseases have a life time prevalence of up to 1 % in western industrialized countries. It is generally proposed that genetic susceptibility, which is much more widespread in the population, needs (unknown) factors in lifestyle in order to lead to disease manifestation. Systematic genome-wide association studies opened a new level of understanding of the risk architecture of inflammatory bowel diseases. This has led to the concept that barrier problems on the level of the intestinal epithelial cells may be a main driver in disease etiopathogenesis. Many of the newly discovered disease genes are not only relevant for inflammatory bowel disease but also for other disorders. This has initiated a large research interest in co-morbidities, which appear to be overlooked on the clinical side, too. Novel therapies should address the primary disease mechanisms and therefore provide causal interventions. Endpoints should include the avoidance of co-morbidities, which may be a limiting factor for patients with chronically active disease.

[Microbiome and nutrition. The way to a future therapy for chronic inflammatory bowel diseases?]. / Mikrobiom und Ernährung. Therapie der Zukunft für chronisch-entzündliche Darmerkrankungen?

The complex microbiome of the human gut contains an excessive amount of genetic information that is more than 100-fold larger than the human genome. In patients with inflammatory bowel disease diversity of the gut microbiome is significantly reduced and moreover specific phyla are overrepresented or underrepresented. However, the functional capacity of the microflora to generate certain metabolic products containing lipids or amino acids- and more complex regulatory substances is more important that the mere annotation of the microorganisms. Modern pharmacological approaches target the functional capacity and constitution of the microbiome. An important strategy is the development of controlled release formulations that deliver defined lipid, carbohydrate or amino acid products derived from nutritional components targeting gut areas distal to the absorption zones of the upper gastrointestinal tract.

The Transcriptome Analysis and Comparison Explorer--T-ACE: a platform-independent, graphical tool to process large RNAseq datasets of non-model organisms.

MOTIVATION: Next generation sequencing (NGS) technologies allow a rapid and cost-effective compilation of large RNA sequence datasets in model and non-model organisms. However, the storage and analysis of transcriptome information from different NGS platforms is still a significant bottleneck, leading to a delay in data dissemination and subsequent biological understanding. Especially database interfaces with transcriptome analysis modules going beyond mere read counts are missing. Here, we present the Transcriptome Analysis and Comparison Explorer (T-ACE), a tool designed for the organization and analysis of large sequence datasets, and especially suited for transcriptome projects of non-model organisms with little or no a priori sequence information. T-ACE offers a TCL-based interface, which accesses a PostgreSQL database via a php-script. Within T-ACE, information belonging to single sequences or contigs, such as annotation or read coverage, is linked to the respective sequence and immediately accessible. Sequences and assigned information can be searched via keyword- or BLAST-search. Additionally, T-ACE provides within and between transcriptome analysis modules on the level of expression, GO terms, KEGG pathways and protein domains. Results are visualized and can be easily exported for external analysis. We developed T-ACE for laboratory environments, which have only a limited amount of bioinformatics support, and for collaborative projects in which different partners work on the same dataset from different locations or platforms (Windows/Linux/MacOS). For laboratories with some experience in bioinformatics and programming, the low complexity of the database structure and open-source code provides a framework that can be customized according to the different needs of the user and transcriptome project.

MIP-3α expression in macrophages is NOD dependent.

BACKGROUND: The first identified susceptibility gene for Crohn's disease, NOD2, acts as a sensor for the bacterial-wall peptidoglycan fragment muramyl dipeptide (MDP) and activates the transcription factor nuclear factor-κB (NF-κB). Upon NF-κB activation, intestinal macrophages (IMACs) induce expression of macrophage inflammatory protein (MIP)-3α to attract memory T lymphocytes. We therefore investigated the influence of NOD2 ligation of IMAC differentiation and functional MIP-3α induction. METHODS: Human embryonal kidney HEK293 cells were transfected with NOD2 wild-type (NOD2(WT)) and the NOD2 SNP13 variant (NOD2(L1007fsinsC)) and stimulated with MDP. Recruitment of CD45R0+ and Th17 cells was determined by immunohistochemistry. RESULTS: Endogenous NOD2 stimulation was followed by a dose-dependent increase in MIP-3α secretion in MONO-MAC-6 (MM6) cells. MIP-3α mRNA was also significantly (*p < 0.05) induced in HEK293 transfected with NOD2(WT) via MDP ligation. In vivo cell-cell contacts between IMACs and CD45R0+ memory T cells as well as recruitment of Th17 cells in patients of NOD2 variants were unchanged as compared to wild-type patients. CONCLUSION: Our data demonstrate a dose-dependent increase in MIP-3α secretion in the human myeloid cell line MM6 upon MDP. However, MIP-3α-driven recruitment of Th17 cells or CD45R0+ memory T lymphocytes is not affected in patients carrying heterozygous NOD2 variants.

Association of inflammatory bowel disease risk loci with sarcoidosis, and its acute and chronic subphenotypes.

Sarcoidosis is a complex granulomatous inflammatory disorder that shares several clinical and pathogenic features with inflammatory bowel disease (IBD). Postulating a common genetic basis of inflammatory diseases, we tested 106 single-nucleotide polymorphisms (SNPs) that are known or have been suggested to be associated with IBD for a potential association with sarcoidosis and its acute and chronic subphenotypes. We genotyped 1,996 German sarcoidosis patients, comprising 648 acutely and 1,161 chronically affected individuals, 2,622 control subjects, and 342 German trios with affected offspring using SNPlex™ technology. The nonsynonymous SNP rs11209026 (Arg381Gln) in the interleukin (IL)-23 receptor (IL23R) gene was associated with chronic sarcoidosis (OR 0.63; p = 5.58×10(-5)), which was supported by the result of a transmission disequilibrium test analysis in the independent family sample (OR 0.50; p = 0.031). Marker rs12035082 located at chromosome 1q24.3 was found to be associated with the acute subphenotype (OR 1.36; p = 6.80×10(-7)) and rs916977 (HERC2 locus; OR 1.30; p = 4.49×10(-5)) was associated with sarcoidosis. Our results highlight the potential importance of the IL-23 signalling pathway for the development of chronic sarcoidosis. The finding links sarcoidosis pathogenesis to other inflammatory conditions and may contribute to new hypotheses on disease mechanisms.

A genome-wide association study reveals evidence of association with sarcoidosis at 6p12.1.

Sarcoidosis is a complex systemic inflammatory disease of unknown aetiology that is influenced by a variety of genetic and environmental factors. To identify further susceptibility loci for sarcoidosis, a genome-wide association study (GWAS) was conducted in 381 patients and 392 control individuals based on Affymetrix 100k GeneChip data. The top 25 single-nucleotide polymorphisms (SNPs) were selected for validation in an independent study panel (1,582 patients versus 1,783 controls). Variant rs10484410 on chromosome 6p12.1 was significantly associated, with a Bonferroni-corrected p-value of 2.90 × 10⁻² in the validation sample and a nominal p-value of 2.64 × 10⁻4 in the GWAS. Extensive fine mapping of the novel locus narrowed down the signal to a region comprising the genes BAG2, C6orf65, KIAA1586, ZNF451 and RAB23. Verification of the sarcoidosis-associated nonsynonymous SNP rs1040461 in a further independent case-control sample and quantitative mRNA expression studies point to the RAB23 gene as the most likely risk factor. RAB23 is proposed to be involved in antibacterial defence processes and regulation of the sonic hedgehog signalling pathway. The identified association of the 6p12.1 locus with sarcoidosis implicates this locus as a further susceptibility factor and RAB23 as a potential signalling component that may open up new perspectives in the pathophysiology of sarcoidosis.

Functional expression of NOD2 in freshly isolated human peripheral blood γδ T cells.

γδ T cells play an important role in anti-infective immunity. The major subset of human γδ T cells selectively recognizes phosphorylated bacterial metabolites of the isoprenoid biosynthesis pathway, so-called phosphoantigens. The activation of γδ T cells is modulated by functionally expressed innate immune receptors, notably Toll-like receptor 2 and 3. It was also reported that in vitro expanded γδ T cells respond to muramyl dipeptide (MDP), the minimal peptidoglycan motif activating the nucleotide-binding oligomerization domain containing 2 (NOD2) receptor, although it is unknown whether ex vivo isolated human γδ T cells express functional NOD2. Here, we report that freshly isolated, highly purified peripheral blood γδ T cells express NOD2 mRNA and detectable amounts of NOD2 protein. The biologically active MDP L-D isomer but not the inactive D-D isomer augmented the interferon-γ (IFN-γ) secretion in phosphoantigen-stimulated peripheral blood mononuclear cells. Moreover, a moderate but reproducible and statistically significant increase in IFN-γ secretion was also observed when highly purified peripheral blood γδ T cells were activated by T cell receptor cross-linking in the presence of MDP. Taken together, our results indicate that in addition to the T cell receptor and Toll-like receptors, circulating human γδ T cells express NOD2 as a third class of pattern recognition receptor for sensing bacterial products.

Coagulation and inflammation. Molecular insights and diagnostic implications.

Overwhelming evidence has linked inflammatory disorders to a hypercoagulable state. In fact, thromboembolic complications are among the leading causes of disability and death in many acute and chronic inflammatory diseases. Despite this clinical knowledge, coagulation and immunity were long regarded as separate entities. Recent studies have unveiled molecular underpinnings of the intimate interconnection between both systems. The studies have clearly shown that distinct pro-inflammatory stimuli also activate the clotting cascade and that coagulation in turn modulates inflammatory signaling pathways. In this review, we use evidence from sepsis and inflammatory bowel diseases as a paradigm for acute and chronic inflammatory states in general and rise hypotheses how a systematic molecular understanding of the "inflammation-coagulation" crosstalk may result in novel diagnostic and therapeutic strategies that target the inflammation-induced hypercoagulable state.

Microbial Butyrate Synthesis Indicates Therapeutic Efficacy of Azathioprine in IBD Patients.

BACKGROUND AND AIMS: The microbial ecosystem seems to be an important player for therapeutic intervenption in inflammatory bowel disease [IBD]. We assessed longitudinal microbiome changes in IBD patients undergoing therapy with either azathioprine [AZA] or anti-tumour necrosis factor [anti-TNF] antibodies. We predicted the metabolic microbial community exchange and linked it to clinical outcome. METHODS: Faecal and blood samples were collected from 65 IBD patients at baseline and after 12 and 30 weeks on therapy. Clinical remission was defined as Crohn's Disease Activity Index [CDAI] < 150 in Crohn´s disease [CD], partial Mayo score <2 in ulcerative colitis [UC], and faecal calprotectin values <150 µg/g and C-reactive protein <5 mg/dl. 16S rRNA amplicon sequencing was performed. To predict microbial community metabolic processes, we constructed multispecies genome-scale metabolic network models. RESULTS: Paired Bray-Curtis distance between baseline and follow-up time points was significantly different for UC patients treated with anti-TNF antibodies. Longitudinal changes in taxa composition at phylum level showed a significant decrease of Proteobacteria and an increase of Bacteroidetes in CD patients responding to both therapies. At family level, Lactobacilli were associated with persistent disease and Bacteroides abundance with remission in CD. In-silico simulations of microbial metabolite exchange predicted a 1.7-fold higher butyrate production capacity of patients in remission compared with patients without remission [p = 0.041]. In this model, the difference in butyrate production between patients in remission and patients without remission was most pronounced in the CD group treated with AZA [p = 0.008]. CONCLUSIONS: In-silico simulation identifies microbial butyrate synthesis predictive of therapeutic efficacy in IBD.

Both copy number and sequence variations affect expression of human DEFB4.

Copy number variations (CNVs) were found to contribute massively to the variability of genomes. One of the best studied CNV region is the beta-defensin cluster (DEFB) on 8p23.1. Individual DEFFB copy numbers (CNs) between 2 and 12 were found, whereas low CNs predispose for Crohn's disease. A further level of complexity is represented by sequence variations between copies (multisite variations, MSVs). To address the relation of DEFB CN and MSV to the expression of beta-defensin genes, we analyzed DEFB4 expression in B-lymphoblastoid cell lines (LCLs) and primary keratinocytes (normal human epidermal keratinocyte, NHEK) before and after stimulation with lipopolysaccharide, tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). Moreover, we quantified one DEFB4 MSV in DNA and mRNA as a marker for variant-specific expression (VSE) and resequenced a region of approximately 2 kb upstream of DEFB4 in LCLs. We found a strong correlation of DEFB CN and DEFB4 expression in 16 LCLs, although several LCLs with very different CNs exhibit similar expression levels. Quantification of the MSV revealed VSE with consistently lower expression of one variant. Costimulation of NHEKs with TNF-alpha/IFN-gamma leads to a synergistic increase in total DEFB4 expression and suppresses VSE. Analysis of the DEFB4 promoter region showed remarkably high density of sequence variabilities (approximately 1 MSV/41 bp).

The angiotensin II type 2 (AT2) receptor promotes axonal regeneration in the optic nerve of adult rats.

The renin-angiotensin system (RAS) has been traditionally linked to blood pressure and volume regulation mediated through the angiotensin II (ANG II) type 1 (AT1) receptor. Here we report that ANG II via its ANG II type 2 (AT2) receptor promotes the axonal elongation of postnatal rat retinal explants (postnatal day 11) and dorsal root ganglia neurons in vitro, and, moreover, axonal regeneration of retinal ganglion cells after optic nerve crush in vivo. In retinal explants, ANG II (10(-7)-10(-5) M) induced neurite elongation via its AT2 receptor, since the effects were mimicked by the AT2 receptor agonist CGP 42112 (10(-5) M) and were entirely abolished by costimulation with the AT2 receptor antagonist PD 123177 (10(-5) M), but not by the AT1 receptor antagonist losartan (10(-5) M). To investigate whether ANG II is able to promote axonal regeneration in vivo, we performed optic nerve crush experiments in the adult rats. After ANG II treatment (0.6 nmol), an increased number of growth-associated protein (GAP)-43-positive fibers was detected and the regenerating fibers regularly crossed the lesion site (1.6 mm). Cotreatment with the AT2 receptor antagonist PD 123177 (6 nmol), but not with the AT1 receptor antagonist losartan (6 nmol), completely abolished the ANG II-induced axonal regeneration, providing for the first time direct evidence for receptor-specific neurotrophic action of ANG II in the central nervous system of adult mammals and revealing a hitherto unknown function of the RAS.

Towards a European health research and innovation cloud (HRIC).

The European Union (EU) initiative on the Digital Transformation of Health and Care (Digicare) aims to provide the conditions necessary for building a secure, flexible, and decentralized digital health infrastructure. Creating a European Health Research and Innovation Cloud (HRIC) within this environment should enable data sharing and analysis for health research across the EU, in compliance with data protection legislation while preserving the full trust of the participants. Such a HRIC should learn from and build on existing data infrastructures, integrate best practices, and focus on the concrete needs of the community in terms of technologies, governance, management, regulation, and ethics requirements. Here, we describe the vision and expected benefits of digital data sharing in health research activities and present a roadmap that fosters the opportunities while answering the challenges of implementing a HRIC. For this, we put forward five specific recommendations and action points to ensure that a European HRIC: i) is built on established standards and guidelines, providing cloud technologies through an open and decentralized infrastructure; ii) is developed and certified to the highest standards of interoperability and data security that can be trusted by all stakeholders; iii) is supported by a robust ethical and legal framework that is compliant with the EU General Data Protection Regulation (GDPR); iv) establishes a proper environment for the training of new generations of data and medical scientists; and v) stimulates research and innovation in transnational collaborations through public and private initiatives and partnerships funded by the EU through Horizon 2020 and Horizon Europe.

Toll-like receptor-induced granulocyte-macrophage colony-stimulating factor secretion is impaired in Crohn's disease by nucleotide oligomerization domain 2-dependent and -independent pathways.

Pattern recognition receptors (PRRs) are an integral part of the innate immune system and govern the early control of foreign microorganisms. Single nucleotide polymorphisms (SNPs) in the intracellular pattern recognition receptor nucleotide-binding oligomerization domain-containing protein (NOD2, nucleotide oligomerization domain 2) are associated with Crohn's disease (CD). We investigated the impact of NOD2 polymorphisms on cytokine secretion and proliferation of peripheral blood mononuclear cells (PBMCs) in response to Toll-like receptor (TLR) and NOD2 ligands. Based on NOD2 SNP analyses, 41 CD patients and 12 healthy controls were studied. PBMCs were stimulated with NOD2 and TLR ligands. After 18 h culture supernatants were measured using multiplex assays for the presence of human cytokines granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-1 beta and tumour necrosis factor (TNF)-alpha. In CD patients, TLR-induced GM-CSF secretion was impaired by both NOD2-dependent and -independent mechanisms. Moreover, TNF-alpha production was induced by a TLR-2 ligand, but a down-regulatory function by the NOD2 ligand, muramyl dipeptide, was impaired significantly in CD patients. Intracellular TLR ligands had minimal effect on GM-CSF, TNF-alpha and IL-1beta secretion. CD patients with NOD2 mutations were able to secrete TNF-alpha, but not GM-CSF, upon stimulation with NOD2 and TLR-7 ligands. CD patients have impaired GM-CSF secretion via NOD2-dependent and -independent pathways and display an impaired NOD2-dependent down-regulation of TNF-alpha secretion. The defect in GM-CSF secretion suggests a hitherto unknown role of NOD2 in the pathogenesis of CD and is consistent with the hypothesis that impaired GM-CSF secretion in part constitutes a NOD2-dependent disease risk factor.

Suppression of MAP kinases inhibits microglial activation and attenuates neuronal cell death induced by alpha-synuclein protofibrils.

Alpha-Synuclein (alpha-Syn) accounts, as a major component of Lewy bodies (LB), for the filamentous deposits in many cases of neurodegenerative diseases. Yet, little is known about the molecular mechanisms of neuronal loss in these diseases. The correlation between alpha-Syn oligomerization/aggregation and pathologies raises the key question of which molecular form of alpha-Syn (i.e. monomeric alpha-Syn, protofibrils or mature fibrils) represents the damage-inducing culprit in the scenario of synucleinopathies. We show that human alpha-Syn protofibrils (PFs) are potent activators of parallel proinflammatory signalling pathways (p38 and ERK1/2 MAP kinases and NF-kappaB) in microglial cells in vitro. Furthermore, stereotactic injection of alpha-Syn PFs into the substantia nigra of adult rats leads to a profound activation of microglia and adjacent neuronal cell loss, which can be attenuated by the MAP kinase inhibitor semapimod. We propose that the neurodegenerative process of alpha-synucleinopathies involves microglial activation through alpha-Syn released or extruded from cells with pathogenic alpha-Syn metabolism. Compounds that inhibit the MAPK/NF-kappaB pathways might be a promising pharmacological strategy for the treatment of the inflammatory component of synucleinopathies including PD.

Debugging the intestinal microbiota in IBD.

Besides its role in repelling enteropathogenic infections, the gastrointestinal tract is in intimate contact with commensal microbiota. Tremendous advances have been made in determining the pivotal role of the microbiota in both tissue homeostasis and metabolism, as well as in the initiation and maintenance of inflammatory lesions in inflammatory bowel diseases. A better understanding of human gut microbiota could provide innovative targets for treating and/or curing such common immunopathologies of the gastrointestinal tract.

Systematic expression profiling of innate immune genes defines a complex pattern of immunosenescence in peripheral and intestinal leukocytes.

Immunosenescence is characterized by a quantitative decline of adequate immune responses, which renders the elderly individual particularly susceptible to bacterial, viral and fungal pathogens. Whereas changes of the aging adaptive immune system (for example, reduced immunoglobulin secretion) have been extensively characterized, alterations of the innate immune system are still poorly understood. The aim of the present study was to systematically examine mRNA expression levels of innate immune genes and proinflammatory cytokines in peripheral and intestinal leukocytes of subjects of different ages. In both, whole blood samples and in colonic biopsies most of the Toll-like receptors (TLRs) and nucleotide-binding and oligomerization domain-like receptors (NLRs) transcript levels were significantly downregulated in elderly subjects (90-99 years). Older individuals, when compared to the younger, exhibited an increased expression and/or secretion of proinflammatory cytokines by peripheral and intestinal leukocytes as well as an increased level of nuclear factor-kappaB activation in colonic biopsies. The observed downregulation of TLRs and NLRs during the aging process may contribute to the lack of effective recognition of invading pathogens or the commensal flora. This effect results in aberrant secondary immune cell activation and could significantly contribute to morbidity and mortality at advanced age.

A dietary flavone confers communicable protection against colitis through NLRP6 signaling independently of inflammasome activation.

Flavones represent a class of polyphenols that are found in many plant-derived food sources. Herein, we provide evidence that the anti-inflammatory and antiproliferative effect of the flavone apigenin relies on the regulation of the gut microbiota by the NOD-like receptor family pyrin domain containing 6 (Nlrp6). When challenged by dextran sulfate sodium (DSS) in drinking water, mice were protected against colitis upon cohousing with apigenin-treated animals. In contrast, the protective effect was lost in the absence of Nlrp6. Sequencing of the 16S ribosomal RNA gene revealed a shift in the composition of the gut microbiota in apigenin-treated mice that was not observed in the absence of Nlrp6. Equally important, we find that the antiproliferative effect of apigenin was dominantly transmitted after cohousing, while being compromised in Nlrp6-deficient mice. In contrast, the symptoms of colitis were alleviated upon apigenin administration even in the absence of either caspase-1/11 or Asc. Collectively, these data indicate that apigenin modulated an inflammasome-independent mechanism by which Nlrp6 reprograms the gut microbiota for protecting mice against colitis. Our study highlights a modulation of the Nlrp6 signaling pathway by a prominent constituent of the human diet that may point toward improved ways to treat inflammatory bowel diseases.

Differences between BCL2-break positive and negative follicular lymphoma unraveled by whole-exome sequencing.

Depending on disease stage follicular lymphoma (FL) lack the t(14;18) in ~15-~50% of cases. Nevertheless, most of these cases express BCL2. To elucidate mechanisms triggering BCL2 expression and promoting pathogenesis in t(14;18)-negative FL, exonic single-nucleotide variant (SNV) profiles of 28 t(14;18)-positive and 13 t(14;18)-negative FL were analyzed, followed by the integration of copy-number changes, copy-neutral LOH and published gene-expression data as well as the assessment of immunoglobulin N-glycosylation sites. Typical FL mutations also affected t(14;18)-negative FL. Curated gene set/pathway annotation of genes mutated in either t(14;18)-positive or t(14;18)-negative FL revealed a strong enrichment of same or similar gene sets but also a more prominent or exclusive enrichment of immune response and N-glycosylation signatures in t(14;18)-negative FL. Mutated genes showed high BCL2 association in both subgroups. Among the genes mutated in t(14;18)-negative FL 555 were affected by copy-number alterations and/or copy-neutral LOH and 96 were differently expressed between t(14;18)-positive and t(14;18)-negative FL (P<0.01). N-glycosylation sites were detected considerably less frequently in t(14;18)-negative FL. These results suggest a diverse portfolio of genetic alterations that may induce or regulate BCL2 expression or promote pathogenesis of t(14;18)-negative FL as well as a less specific but increased crosstalk with the microenvironment that may compensate for the lack of N-glycosylation.