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Abstract Rheumatoid arthritis (RA) is a fluctuating progressive disease requiring frequent symptom assessment for appropriate management. Continuous tracking using digital technologies may provide greater insights of a patient’s experience. This prospective study assessed the feasibility, reliability, and clinical utility of using novel digital technologies to remotely monitor participants with RA. Participants with moderate to severe RA and non-RA controls were monitored continuously for 14 days using an iPhone with an integrated bespoke application and an Apple Watch. Participants completed patient-reported outcome measures and objective guided tests designed to assess disease-related impact on physical function. The study was completed by 28 participants with RA, 28 matched controls, and 2 unmatched controls. Completion rates for all assessments were > 97% and were reproducible over time. Several guided tests distinguished between RA and control cohorts (e.g., mean lie-to-stand time [seconds]: RA: 4.77, control: 3.25; P

BackgroundConcerns regarding potential risk of dermal irritation have led to the exclusion of NICU patients from the recommendation regarding the use of 2% chlorhexidine gluconate (CHG) wash for daily skin cleansing to reduce bloodstream infections. Our aim was to assess the safety of 2% CHG bathing in NICU patients.MethodsThe regulator required a stepwise study enrollment to three successive groups: term infants, followed by near-term and pre-term infants. For comparison, we used a cohort of matched controls. A propensity score-adjusted regression model was used to compare the groups.InterventionInfants were bathed thrice-weekly with 2% CHG-impregnated washcloths. Participant's skin was examined daily.ResultsOver a total of 661 days of treatment: 384,129, and 148 days for the term, near-term and pre-term groups, respectively, no skin reactions were observed. The intervention group was generally sicker, however, bloodstream infections were similar between the groups.ConclusionFor infants >30 weeks and >3 days old, 2% CHG bathing was safe. Large multicenter studies are urgently needed to establish the effectiveness of this practice in the NICU.

Retinoic acid (RA) is a central signaling molecule regulating multiple developmental decisions during embryogenesis. Excess RA induces head malformations, primarily by expansion of posterior brain structures at the expense of anterior head regions, i.e., hindbrain expansion. Despite this extensively studied RA teratogenic effect, a number of syndromes exhibiting microcephaly, such as DiGeorge, Vitamin A Deficiency, Fetal Alcohol Syndrome, and others, have been attributed to reduced RA signaling. This causative link suggests a requirement for RA signaling during normal head development in all these syndromes. To characterize this novel RA function, we studied the involvement of RA in the early events leading to head formation in Xenopus embryos. This effect was mapped to the earliest RA biosynthesis in the embryo within the gastrula Spemann-Mangold organizer. Head malformations were observed when reduced RA signaling was induced in the endogenous Spemann-Mangold organizer and in the ectopic organizer of twinned embryos. Two embryonic retinaldehyde dehydrogenases, ALDH1A2 (RALDH2) and ALDH1A3 (RALDH3) are initially expressed in the organizer and subsequently mark the trunk and the migrating leading edge mesendoderm, respectively. Gene-specific knockdowns and CRISPR/Cas9 targeting show that RALDH3 is a key enzyme involved in RA production required for head formation. These observations indicate that in addition to the teratogenic effect of excess RA on head development, RA signaling also has a positive and required regulatory role in the early formation of the head during gastrula stages. These results identify a novel RA activity that concurs with its proposed reduction in syndromes exhibiting microcephaly.

Robustness is a feature of regulatory pathways to ensure signal consistency in light of environmental changes or genetic polymorphisms. The retinoic acid (RA) pathway, is a central developmental and tissue homeostasis regulatory signal, strongly dependent on nutritional sources of retinoids and affected by environmental chemicals. This pathway is characterized by multiple proteins or enzymes capable of performing each step and their integration into a self-regulating network. We studied RA network robustness by transient physiological RA signaling disturbances followed by kinetic transcriptomic analysis of the recovery during embryogenesis. The RA metabolic network was identified as the main regulated module to achieve signaling robustness using an unbiased pattern analysis. We describe the network-wide responses to RA signal manipulation and found the feedback autoregulation to be sensitive to the direction of the RA perturbation: RA knockdown exhibited an upper response limit, whereas RA addition had a minimal feedback-activation threshold. Surprisingly, our robustness response analysis suggests that the RA metabolic network regulation exhibits a multi-objective optimization, known as Pareto optimization, characterized by trade-offs between competing functionalities. We observe that efficient robustness to increasing RA is accompanied by worsening robustness to reduced RA levels and vice versa. This direction-dependent trade-off in the network-wide feedback response, results in an uneven robustness capacity of the RA network during early embryogenesis, likely a significant contributor to the manifestation of developmental defects.

Antibodies are critical components of adaptive immunity, binding with high affinity to pathogenic epitopes. Antibodies undergo rigorous selection to achieve this high affinity, yet some maintain an additional basal level of low affinity, broad reactivity to diverse epitopes, a phenomenon termed ‘polyreactivity’. While polyreactivity has been observed in antibodies isolated from various immunological niches, the biophysical properties that allow for promiscuity in a protein selected for high-affinity binding to a single target remain unclear. Using a database of over 1000 polyreactive and non-polyreactive antibody sequences, we created a bioinformatic pipeline to isolate key determinants of polyreactivity. These determinants, which include an increase in inter-loop crosstalk and a propensity for a neutral binding surface, are sufficient to generate a classifier able to identify polyreactive antibodies with over 75% accuracy. The framework from which this classifier was built is generalizable, and represents a powerful, automated pipeline for future immune repertoire analysis.

Retinoic acid (RA) is a major regulatory signal during embryogenesis produced from vitamin A (retinol) by an extensive, autoregulating metabolic and signaling network to prevent fluctuations that result in developmental malformations. Xenopus laevis is an allotetraploid hybrid frog species whose genome includes L (long) and S (short) chromosomes from the originating species. Evolutionarily, the X. laevis subgenomes have been losing either L or S homoeologs in about 43% of genes to generate singletons. In the RA network, out of the 47 genes, about 47% have lost one of the homoeologs, like the genome average. Interestingly, RA metabolism genes from storage (retinyl esters) to retinaldehyde production exhibit enhanced gene loss with 75% singletons out of 28 genes. The effect of this gene loss on RA signaling autoregulation was studied. Employing transient RA manipulations, homoeolog gene pairs were identified in which one homoeolog exhibits enhanced responses or looser regulation than the other, while in other pairs both homoeologs exhibit similar RA responses. CRISPR/Cas9 targeting of individual homoeologs to reduce their activity supports the hypothesis where the RA metabolic network gene loss results in tighter network regulation and more efficient RA robustness responses to overcome complex regulation conditions.

Aim: To investigate glycaemic outcomes in youths and adults with type 1 diabetes with either MiniMed™ 780G or Tandem t:slim X2™ control‐IQ automated insulin delivery (AID) systems and to evaluate clinical factors that migrate, mitigate the achievement of therapeutic goals. Materials and Methods: This retrospective, real‐world, observational study was conducted in a specialized university type 1 diabetes centre with patients observed for 3‐12 months post‐initiation of an AID system. Primary outcomes were the percentage time in the target glucose range [TIR70‐180 mg/dl (3.9‐10 mmol/L)] as measured by continuous glucose monitoring, mean glucose management indicator (GMI) and glycated haemoglobin (HbA1c) levels. Results: Our study cohort consisted of 48 adolescents and 183 adults (55% females) aged 10‐77 years. The mean (95% confidence interval) TIR70‐180 mg/dl after 30 days was higher than baseline and by 14% points after 360 days with 71.33% (69.4‐73.2) (n = 123, p <.001). HbA1c levels decreased by 0.7% and GMI by 0.6% after 360 days. The proportion of time spent <70 mg/dl (3.9 mmol/L) was not significantly different from baseline. During follow‐up, 780G users had better continuous glucose monitoring results than control‐IQ users but similar HbA1c levels, and an increased risk of weight gain. Age at onset influenced TIR70‐180 mg/dl in univariate analysis but there was no significant relationship after adjusting on explanatory variables. Baseline body mass index did not influence the performance of AID systems. Conclusions: This analysis showed the beneficial effects of two AID systems for people with type 1 diabetes across a broad spectrum of participant characteristics. Only half of the participants achieved international recommendations for glucose control with TIR70‐180 mg/dl >70%, HbA1c levels or GMI <7%, which outlines the need to maintain strong educational and individual strategies. [ABSTRACT FROM AUTHOR]

Zbtb16-encoded transcription factor PLZF directs the differentiation of multiple innate and innate-like cell lineages, but how Zbtb16 itself is regulated remains unclear. Here the authors show, using CRISPR gene editing, ATAC-seq and ChIP-seq, that specific Runx1-bound enhancer elements critically modulate lineage-dependent expressions of PLZF.

We describe the clinical, hematologic and genetic characteristics of a retrospective series of 126 subjects from 64 families with hereditary xerocytosis. Twelve patients from six families carried a KCNN4 mutation, five had the recurrent p.Arg352His mutation and one had a new deletion at the exon 7-intron 7 junction. Forty-nine families carried a PIEZO1 mutation, which was a known recurrent mutation in only one-third of the cases and private sequence variation in others; 12 new probably pathogenic missense mutations were identified. The two dominant features leading to diagnosis were hemolysis that persisted after splenectomy and hyperferritinemia, with an inconstant correlation with liver iron content assessed by magnetic resonance imaging. PIEZO1-hereditary xerocytosis was characterized by compensated hemolysis in most cases, perinatal edema of heterogeneous severity in more than 20% of families and a major risk of post-splenectomy thrombotic events, including a high frequency of portal thrombosis. In KCNN4-related disease, the main symptoms were more severe anemia, hemolysis and iron overload, with no clear sign of red cell dehydration; therefore, this disorder would be better described as a ‘Gardos channelopathy’. These data on the largest series to date indicate that PIEZO1-hereditary xerocytosis and Gardos channelopathy are not the same disease although they share hemolysis, a high rate of iron overload and inefficient splenectomy. They demonstrate the high variability in clinical expression as well as genetic bases of PIEZO1-hereditary xerocytosis. These results will help to improve the diagnosis of hereditary xerocytosis and to provide recommendations on the clinical management in terms of splenectomy, iron overload and pregnancy follow-up.

Mechanisms related to the induction of phlorotannin biosynthesis in marine brown algae remain poorly known. Several studies undertaken on fucoid species have shown that phlorotannins accumulate in the algae for several days or weeks after being exposed to grazing, and this is measured by direct quantification of soluble phenolic compounds. In order to investigate earlier inducible responses involved in phlorotannin metabolism, Fucus vesiculosus was studied between 6 and 72 h of grazing by the sea snail Littorina littorea. In this study, the quantification of soluble phenolic compounds was complemented by a Quantitative real-time PCR (qRT-PCR) approach applied on genes that are potentially involved in either the phlorotannin metabolism or stress responses. Soluble phlorotannin levels remained stable during the kinetics and increased significantly only after 12 h in the presence of grazers, compared to the control, before decreasing to the initial steady state for the rest of the kinetics. Under grazing conditions, the expression of vbpo, cyp450 and ast6 genes was upregulated, respectively, at 6 h, 12 h and 24 h, and cyp450 gene was downregulated after 72 h. Interestingly, the pksIII gene involved in the synthesis of phloroglucinol was overexpressed under grazing conditions after 24 h and 72 h. This study supports the hypothesis that phlorotannins are able to provide an inducible chemical defense under grazing activity, which is regulated at different stages of the stress response.

CD1d-deficiency results in a selective deletion of NKT cells in mice that is reported to prevent murine allergic airway disease (AAD). Because we find 2-3 fold lower basal IL-4 production in CD1d- mice than in wild-type (WT) mice, we hypothesized that the contribution made by NKT cells to AAD would depend on the strength of the stimulus used to induce the disease. Consequently, we compared CD1d-deficient mice to WT mice in the development of AAD, using several models of disease induction that differed in the type and dose of allergen, the site of sensitization and the duration of immunization. Surprisingly we found equivalent allergic inflammation and airway disease in WT and CD1d- mice in all models investigated. Consistent with this, NKT cells constituted only ~2% of CD4+ T cells in the lungs of mice with AAD, and IL-4-transcribing NKT cells did not expand with disease induction. Concerned that the congenital absence of NKT cells might have caused a compensatory shift within the immune response, we administered an anti-CD1d monoclonal Ab (mAb) to block NKT function before airway treatments, before or after systemic sensitization to antigen. Such Ab treatment did not affect disease severity. We suggest that the differences reported in the literature regarding the significance of NKT cells in the induction of allergic airway disease may have less to do with the methods used to study the disease and more to do with the animals themselves and/or the facilities used to house them.

Natural killer T (NKT) cells are a subset of T cells that recognize glycolipid antigens presented by the CD1d protein. The initial discovery of immunostimulatory glycolipids from a marine sponge and the T cells that respond to the compounds has led to extensive research by chemists and immunologists to understand how glycolipids are recognized, possible responses by NKT cells, and the structural features of glycolipids necessary for stimulatory activity. The presence of this cell type in humans and most mammals suggests that it plays critical roles in antigen recognition and the interface between innate and adaptive immunity. Both endogenous and exogenous natural antigens for NKT cells have been identified, and it is likely that glycolipid antigens remain to be discovered. Multiple series of structurally varied glycolipids have been synthesized and tested for stimulatory activity. The structural features of glycolipids necessary for NKT cell stimulation are moderately well understood, and designed compounds have proven to be much more potent antigens than their natural counterparts. Nevertheless, control over NKT cell responses by designed glycolipids has not been optimized, and further research will be required to fully reveal the therapeutic potential of this cell type.

Background: Concerns regarding potential risk of dermal irritation have led to the exclusion of NICU patients from the recommendation regarding the use of 2% chlorhexidine gluconate (CHG) wash for daily skin cleansing to reduce bloodstream infections. Our aim was to assess the safety of 2% CHG bathing in NICU patients. Methods: The regulator required a stepwise study enrollment to three successive groups: term infants, followed by near-term and pre-term infants. For comparison, we used a cohort of matched controls. A propensity score-adjusted regression model was used to compare the groups. Intervention: Infants were bathed thrice-weekly with 2% CHG-impregnated washcloths. Participant's skin was examined daily. Results: Over a total of 661 days of treatment: 384,129, and 148 days for the term, near-term and pre-term groups, respectively, no skin reactions were observed. The intervention group was generally sicker, however, bloodstream infections were similar between the groups. Conclusion: For infants >30 weeks and >3 days old, 2% CHG bathing was safe. Large multicenter studies are urgently needed to establish the effectiveness of this practice in the NICU. [ABSTRACT FROM AUTHOR]

A committed precursor to innate lymphoid cell lineages, but not classical natural killer and lymphoid tissue inducer cells, is derived from common lymphoid precursors and distinguished by high levels of expression of the transcription factor PLZF. Innate lymphoid cell precursors identified Knowledge of the developmental pathways and lineage relationships of the precursors to innate lymphocytes is important because these cells serve key protective functions in infection and homeostasis at mucosal barriers, and because of their crosstalk with epithelium and microbiota. This study identifies a committed common lymphoid-derived precursor to innate lymphoid cell (ILC) lineages. The progenitor cells, termed ILCPs (innate lymphoid cell precursors), are distinct from classical natural killer (NK) and lymphoid tissue inducer cells, thus demonstrating that similar functional programs arise independently in different lineages of innate lymphocytes. The findings also imply the presence of highly specialized innate lymphoid lineages within what was previously regarded as a broader NK-cell population. Innate lymphoid cells (ILCs) specialize in the rapid secretion of polarized sets of cytokines and chemokines to combat infection and promote tissue repair at mucosal barriers.sup.1,2,3,4,5,6,7,8,9. Their diversity and similarities with previously characterized natural killer (NK) cells and lymphoid tissue inducers (LTi) have prompted a provisional classification of all innate lymphocytes into groups 1, 2 and 3 solely on the basis of cytokine properties.sup.10, but their developmental pathways and lineage relationships remain elusive. Here we identify and characterize a novel subset of lymphoid precursors in mouse fetal liver and adult bone marrow that transiently express high amounts of PLZF, a transcription factor previously associated with NK T cell development.sup.11,12, by using lineage tracing and transfer studies. PLZF.sup.high cells were committed ILC progenitors with multiple ILC1, ILC2 and ILC3 potential at the clonal level. They excluded classical LTi and NK cells, but included a peculiar subset of NK1.1.sup.+DX5.sup.- 'NK-like' cells residing in the liver. Deletion of PLZF markedly altered the development of several ILC subsets, but not LTi or NK cells. PLZF.sup.high precursors also expressed high amounts of ID2 and GATA3, as well as TOX, a known regulator of PLZF-independent NK and LTi lineages.sup.13. These findings establish novel lineage relationships between ILC, NK and LTi cells, and identify the common precursor to ILCs, termed ILCP. They also reveal the broad, defining role of PLZF in the differentiation of innate lymphocytes., Author(s): Michael G. Constantinides [sup.1] , Benjamin D. McDonald [sup.1] , Philip A. Verhoef [sup.1] , Albert Bendelac [sup.1] Author Affiliations: (1) Department of Pathology, Committee on Immunology, The Howard [...]

In the original PDF version of this Article, which was published on 16 October 2017, the publication date was incorrectly given as 11 October 2017. This has now been corrected in the PDF; the HTML version of the paper was correct from the time of publication.

The differentiation of several T- and B-cell effector programs in the immune system is directed by signature transcription factors that induce rapid epigenetic remodelling. Here we report that promyelocytic leukaemia [...]

NKT cells are innate-like T cells with powerful regulatory functions that are a promising target for immunotherapy. The efficacy of glycolipids, such as the prototypic NKT cell antagonist α-galactosylceramide (αGalCer), is currently being evaluated in clinical trials, but little is known about factors that target lipid antigens for CD1d presentation and NKT cell activation in vivo. Lipid uptake via the LDL receptor (LDLR) has been shown for digalactosylceramide; however, whether this pathway contributes to CD1d presentation of other important NKT cell agonists remains unclear. We therefore investigated receptor-mediated uptake pathways for CD1d presentation using a panel of structurally diverse lipid antigens. We found that uptake via scavenger receptors was essential for the CD1d presentation of αGalCer and Sphingomonas glycolipids. Moreover, in vivo NKT cell responses, i.e., cytokine production, proliferation, and NKT cell help for adaptive [CD4.sup.+] and [CD8.sup.+] T cells, required the uptake of αGalCer via scavenger receptor A. Importantly, our data indicate that structural characteristics of glycolipids determine their receptor binding and direct individual lipids toward different uptake pathways. These results reveal an important contribution of scavenger receptors in the selection of lipids for CD1d presentation and identify structural motifs that may prove useful for therapeutic NKT cell vaccination., Introduction The efficacy of current vaccines depends on adjuvants, microbial products that activate the innate immune system by triggering pattern recognition receptors (PRRs), such as TLRs or NOD-like receptors (NLRs) [...]

The potent regulatory properties of NKT cells render this subset of lipid-specific T cells a promising target for immunotherapeutic interventions. The marine sponge glycolipid α]-galactosylceramide (αGalCer) is the prototypic NKT cell agonist, which elicits this function when bound to CD1d. However, our understanding of the in vivo properties of NKT cell agonists and the host factors that control their bioactivity remains very limited. In this report, we isolated the enzyme fatty acid amide hydrolase (FAAH) from mouse serum as an αGalCer-binding protein that modulates the induction of key effector functions of NKT cells in vivo. FAAH bound αGalCer in vivo and in vitro and was required for the efficient targeting of lipid antigens for CD1d presentation. Immunization of Faah-deficient mice with αGalCer resulted in a reduced systemic cytokine production, but enhanced expansion of splenic NKT cells. This distinct NKT response conferred a drastically increased adjuvant effect and strongly promoted protective CTL responses. Thus, our findings identify not only the presence of FAAH in normal mouse serum, but also its critical role in the tuning of immune responses to lipid antigens by orchestrating their transport and targeting for NKT cell activation. Our results suggest that the serum transport of lipid antigens directly shapes the quality of NKT cell responses, which could potentially be modulated in support of novel vaccination strategies., Introduction The NKT cell population represents a specialized subset of lipid antigen-specific T cells with important regulatory functions (1-3). NKT cells are characterized by the expression of an invariant Vα [...]