N6-Methyladenosine Promotes TNF mRNA Degradation In CD4+ T Lymphocytes

N6-methyladenosine (m6A) is a RNA modification that can regulate post-transcriptional processes including RNA stability, translation, splicing and nuclear export. In CD4+ lymphocytes, m6A modifications have been demonstrated to play a role in early differentiation processes. The role of m6A in CD4+ T cell activation and effector function remains incompletely understood. To assess the role of m6A in CD4+ T lymphocyte activation and function, we assessed the transcriptome-wide m6A landscape of human primary CD4+ T cells by methylated RNA immunoprecipitation (meRIP) sequencing. Stimulation of the T cells impacted the m6A pattern of hundreds of transcripts including tumor necrosis factor (TNF). m6A methylation was increased on TNF mRNA after activation, predominantly in the 3' untranslated region (UTR) of the transcript. Manipulation of m6A levels in primary human T cells, the directly affected the expression of TNF. Furthermore, we identified that the m6A reader protein YT521-B homology domain family-2 (YTHDF2) binds m6A-methylated TNF mRNA, and promotes its degradation. Taken together, this study demonstrates that TNF expression in CD4+ T lymphocytes is regulated via m6A and YTHDF2, thereby providing novel insight into the regulation of T cell effector functions.

The genomic evolutionary dynamics and global circulation patterns of respiratory syncytial virus

Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory tract infection in young children and the second leading cause of infant death worldwide. While global circulation has been extensively studied for respiratory viruses such as seasonal influenza, and more recently also in great detail for SARS-CoV-2, a lack of global multi-annual sampling of complete RSV genomes limits our understanding of RSV molecular epidemiology. Here, we capitalise on the genomic surveillance by the INFORM-RSV study and apply phylodynamic approaches to uncover how selection and neutral epidemiological processes shape RSV diversity. Using complete viral genome sequences, we show similar patterns of site-specific diversifying selection among RSVA and RSVB and recover the imprint of non-neutral epidemic processes on their genealogies. Using a phylogeographic approach, we provide evidence for air travel governing the global patterns of RSVA and RSVB spread, which results in a considerable degree of phylogenetic mixing across countries. Our findings highlight the potential of systematic global RSV genomic surveillance for transforming our understanding of global RSV spread.

N6-Methyladenosine Directly Regulates CD40L Expression in CD4+ T Lymphocytes

T cell activation is a highly regulated process, modulated via the expression of various immune regulatory proteins including cytokines, surface receptors and co-stimulatory proteins. N⁶-methyladenosine (m⁶A) is an RNA modification that can directly regulate RNA expression levels and it is associated with various biological processes. However, the function of m⁶A in T cell activation remains incompletely understood. We identify m⁶A as a novel regulator of the expression of the CD40 ligand (CD40L) in human CD4⁺ lymphocytes. Manipulation of the m⁶A 'eraser' fat mass and obesity-associated protein (FTO) and m⁶A 'writer' protein methyltransferase-like 3 (METTL3) directly affects the expression of CD40L. The m⁶A 'reader' protein YT521-B homology domain family-2 (YTHDF2) is hypothesized to be able to recognize and bind m⁶A specific sequences on the CD40L mRNA and promotes its degradation. This study demonstrates that CD40L expression in human primary CD4⁺ T lymphocytes is regulated via m⁶A modifications, elucidating a new regulatory mechanism in CD4⁺ T cell activation that could possibly be leveraged in the future to modulate T cell responses in patients with immune-related diseases.

Goal setting within cardiac care: the effect of linking life goals to health goals on intention to change lifestyle in patients

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Dutch Heart Foundation and ZonMw

Goal setting within cardiac care: the effect of linking life goals to health goals on intention to change lifestyle in patients.

Background

Initiating and maintaining a healthy lifestyle is difficult and often needs several attempts. Reaching health goals may become easier if linked to life goals (see Fig.1). Life goals, also described as abstract, long-term goals, reflect objectives that matter to people personally. Guidelines recommend goal setting to realise behaviour change in patients with cardiovascular disease (CVD). However, research is inconclusive about whether positive effects of lifestyle interventions can be attributed to linking life goals to health goals or to other intervention elements.

Purpose

This experimental study examines the effect of linking a life goal to a health goal on intention to change lifestyle in patients with CVD.

Methods

Research panel members of a CVD patient association were recruited for the online study via advertisement on the association’s website. Patients were randomised and controlled into two groups: setting a health goal (HG) and setting a health goal linked to a life goal (+LG). Based on the Theory of Planned Behavior (see Fig.2) and previous research, main outcome measure ‘intention to change lifestyle’ was assessed using a visual analogue scale ranging 0-10 (low to high). Effect of group (HG vs +LG) on intention to change lifestyle (high vs low) was analysed using logistic regression. Gender, age, education level, and type of CVD were entered as possible effect modifiers.

Results

Patients (N=628) were mostly male (61%), with a mean age of 69±35 years, and medium (33%) or high (47%) education level. In both groups, HG and +LG, 47% of the patients expressed high intention to change lifestyle. Logistic regression showed no effect of group (HG vs +LG) on intention, OR:0.98 (95%CI: 0.72–1.35, p=0.92). Only education level appeared to be an effect modifier, X²(2):8.2, p=0.02; showing that linking a life goal to a health goal was effective in patients with a high education level. Contrary to this, setting a life goal negatively affected intention in patients with a low education level. Among patients with a high education level, percentage of 'high intention' was higher in the +LG group (57%) than in the HG group (45%). In contrast, among patients with a low education level, percentage of 'high intention' was higher in the HG group (48%) than in the +LG group (36%).

Conclusions

This study showed no main effect of linking a life goal to a health goal on patients’ intention to change lifestyle. Education level was found to be a significant effect modifier. Patients with a high education level significantly benefitted from linking a life goal to a health goal. Patients with lower education levels benefitted most from setting only a health goal. In conclusion, within practice, health care providers may personalise their approach towards goal setting based on patients’ education level.

Questionnaire use depends on the study goal, target group and phase of the condition

Linked Article: Szabó et al. Br J Dermatol 2022; 186:485–495.

A systematic review on global RSV genetic data: Identification of knowledge gaps

Respiratory syncytial virus (RSV) is a major health problem. A better understanding of the geographical and temporal dynamics of RSV circulation will assist in tracking resistance against therapeutics currently under development. Since 2015, the field of RSV molecular epidemiology has evolved rapidly with around 20–30 published articles per year. The objective of this systematic review is to identify knowledge gaps in recent RSV genetic literature to guide global molecular epidemiology research. We included 78 studies published between 2015 and 2020 describing 12,998 RSV sequences of which 8,233 (63%) have been uploaded to GenBank. Seventeen (22%) studies were performed in low‐ and middle‐income countries (LMICs), and seven (9%) studies sequenced whole‐genomes. Although most reported polymorphisms for monoclonal antibodies in clinical development (nirsevimab, MK‐1654) have not been tested for resistance in neutralisation essays, known resistance was detected at low levels for the nirsevimab and palivizumab binding site. High resistance was found for the suptavumab binding site. We present the first literature review of an enormous amount of RSV genetic data. The need for global monitoring of RSV molecular epidemiology becomes increasingly important in evaluating the effectiveness of monoclonal antibody candidates as they reach their final stages of clinical development. We have identified the following three knowledge gaps: whole‐genome data to study global RSV evolution, data from LMICs and data from global surveillance programs.

Global molecular diversity of RSV - the "INFORM RSV" study

Background

Respiratory syncytial virus (RSV) is a global cause of severe respiratory morbidity and mortality in infants. While preventive and therapeutic interventions are being developed, including antivirals, vaccines and monoclonal antibodies, little is known about the global molecular epidemiology of RSV. INFORM is a prospective, multicenter, global clinical study performed by ReSViNET to investigate the worldwide molecular diversity of RSV isolates collected from children less than 5 years of age.

Methods

The INFORM study is performed in 17 countries spanning all inhabited continents and will provide insight into the molecular epidemiology of circulating RSV strains worldwide. Sequencing of > 4000 RSV-positive respiratory samples is planned to detect temporal and geographical molecular patterns on a molecular level over five consecutive years. Additionally, RSV will be cultured from a subset of samples to study the functional implications of specific mutations in the viral genome including viral fitness and susceptibility to different monoclonal antibodies.

Discussion

The sequencing and functional results will be used to investigate susceptibility and resistance to novel RSV preventive or therapeutic interventions. Finally, a repository of globally collected RSV strains and a database of RSV sequences will be created.

[Assessment of pruritus - current standards and implications for clinical practice : consensus paper of the Action Group Pruritus Parameter of the International Working Group on Pruritus Research (AGP)]

With a prevalence of 20%, chronic pruritus is a symptom of many diseases with major impact on healthcare costs. The lack of specific therapeutic measures makes the development of new drugs and their testing in clinical trials urgent. It is not possible to measure pruritus in an objective way. For these reasons, it is necessary to have a series of standardized measures to characterize pruritus in a reliable way. Intensity scales such as the visual analog scale (VAS) are most frequently used to document the course of the symptoms. However, for assessing pruritus intensity, VAS is not an optimal instrument, although it cannot be dispensed with. The VAS should be combined with other scales in clinical studies in order to internally test the consistency of data. Other instruments for assessing intensity and course of pruritus are in the process of development. Presently scratch activity and scratch-associated lesions can be documented in a descriptive fashion. There are some studies that have employed devices to document scratch activity; however, methodological studies are not yet available. The patient-benefit index is an indispensable tool in clinical trials. A questionnaire for gathering data on the history and some pruritus-specific parameters has been developed and published. Questionnaires on patient quality of life, anxiety and depression are helpful in obtaining data on other cost-relevant parameters. A questionnaire on the quality of life, for instance, can provide important help in the assessment of the burden of the disease. The results of these questionnaires can be correlated with data on pruritus intensity scales. The relevant questionnaires have been partially digitalized so that they are available immediately as part of patient care. Additional methodological developments and studies are required in order to define a robust set of instruments for measuring pruritus in daily practice and in clinical studies.

[Tissue engineering: new treatment of cartilage alterations in degenerative joint diseases in horses--preliminary results of a long term study]

Degenerative alterations in fetlock joints of the forelimb are common diagnoses for horses. The hyaline cartilage has a low capacity to regenerate and the treatment by veterinarians is often insufficient. As a final result, horses with articular cartilage defects are often not able to take part in competitions anymore. To establish an autologous cartilage repair method, we set artificial lesions (8 mm in diameter) into the fetlock joints of the forelimb of three horses. These defects were closed with autologous chondrocyte implants, which were fixed with titan-suture-anchors. After 3, 12 and 24 months, biopsies were taken by arthroscopy. One horse was euthanized after 9, another one after 24 months. The repair tissue was examined histologically and by biochemical analysis of hydroxyproline and glycosaminoglycan, which are typical cartilage related substances. After 9 months, the integration of the implant into native cartilage was demonstrated by electron microscopy. After 24 months, histological staining showed a similar morphology of the cartilage repair tissue compared with the surrounding native cartilage. Biochemical analysis of typical cartilage matrix molecules revealed formation of hyaline-like cartilage within tissue engineered autologous chondrocyte transplants.

The role of helplessness as mediator between neurological disability, emotional instability, experienced fatigue and depression in patients with multiple sclerosis

The aim of this study was to test, in patients with multiple sclerosis (MS), whether the concept of helplessness might improve the understanding of the relationship between disease severity (neurological impairment) and personality characteristics (emotional instability) on one hand, and depressive mood and fatigue severity on the other hand. Data pertain to 89 patients with a definite diagnosis of MS (Expanded Disability Status Scale [EDSS] ratings: 1-8). Helplessness, fatigue severity, depressive mood and emotional instability were rated with validated questionnaires. Model testing revealed that more neurological impairment and more emotional instability were associated with more helplessness, while higher levels of helplessness were associated with more fatigue and depressive mood. The initially observed direct relationship between EDSS and fatigue disappeared. Emotional instability also had a direct significant relationship with depressive mood, and depressive mood had only a small relationship with fatigue severity. The results indicated that helplessness affected both depressive mood and fatigue severity and that fatigue was not merely a symptom of depressive mood. The correlation between neurological impairment and fatigue severity was largely explained by the mediating effect of helplessness. These findings suggest that MS patients troubled by disabling fatigue might benefit from a psychological intervention targeting unfavourable illness cognitions.

PACHIQ-R: the Parent-Child Interaction Questionnaire--revised

The PACHIQ (Parent-Child Interaction Questionnaire) is designed to help clinicians and researchers assess how parents view relationship with their children (PACHIQ-Parent version), and how children evaluate their relationship with their parents (PACHIQ-Child version). The items in this questionnaire refer to both interpersonal behavior and feelings. Conceptually, the PACHIQ is based on learning theory and structural systems theory. The development of the PACHIQ was described by Lange, Blonk and Wiers (1998). The present article reports additional psychometric data obtained in the development and validation of a revised, shorter version of the questionnaire (PACHIQ-R). We present norm tables for families with children who are referred for psychological treatment, and norm tables for families in the normal Dutch population. The PACHIQ-R displays a two-factor structure with factors interpreted as Conflict Resolution and Acceptance. The parent version of the PACHIQ-R contains 21 items, the child version 25 items.

The new Long-Term Care Insurance Program in Germany

The article describes the new Long-Term Care Insurance Program (LTCI), which has been operational in Germany since 1995, as well as the policy issues leading to its enactment. After discussing similarities and differences with the traditional German social insurance-centered welfare system and some of the major weaknesses of the new program, two issues are discussed in more detail: (1) entitlement criteria and reimbursement rules and the ways they influence the conditions and quality of the professional care delivered; (2) the impact of cash as an alternative choice to services. The descriptive and evaluative sections use existing materials and reports; the second section is based, in addition, on a pilot study by the author, which looks at the reasons why so many people entitled to LTCI choose the cash alternative.

Assessment of female sexual arousal: response specificity and construct validity

Specificity of vaginal pulse amplitude and vaginal blood volume in reaction to visual sexual stimuli was investigated by comparing responses to sexual, anxiety-inducing, sexually threatening, and neutral film excerpts. Subjective sexual arousal, body sensations, emotional experience, skin conductance, and heart rate were monitored along with the genital measures. Self-report data confirmed the generation of affective states as intended. Results demonstrated response specificity of vaginal vasocongestion to sexual stimuli. In terms of both convergent and divergent validity, vaginal pulse amplitude was the superior genital measure. Skin conductance discriminated among stimuli only to a small degree, whereas heart rate failed to discriminate among stimuli altogether.

Diacylglycerol metabolism in phospholipase C-treated mammalian cells

Treatment of cultured cells with phospholipase C causes increased rates of hydrolysis of cellular phosphatidylcholine and increased rates of incorporation of choline into phosphatidylcholine. The fate of the diacylglycerol produced by the phospholipase C hydrolysis was examined in two cell lines, Chinese hamster ovary and HeLa. In the former cells, turnover of the glycerol moiety of phosphatidylcholine was not enhanced by phospholipase C treatment, indicating that the phospholipase C-generated diacylglycerol was recycled into new phosphatidylcholine. In HeLa cells, turnover of the glycerol backbone of phosphatidylcholine was enhanced by phospholipase C treatment, and the increased rate of turnover of the glycerol moiety was similar to that of the phosphate moiety. Thus, the fate of diacylglycerol generated at the plasma membrane was demonstrated to differ in these two cell lines. Incorporation of precursors of diacylglycerol into phosphatidylcholine was not enhanced by phospholipase C treatment in either cell line.

A unique cardiac cytosolic acyltransferase with preferential selectivity for fatty acids that form cyclooxygenase/lipoxygenase metabolites and reverse essential fatty acid deficiency

The rabbit heart contains a cytosolic enzyme which selectively incorporates polyunsaturated fatty acids into phosphatidylcholine. This unique acyltransferase is selective for fatty acids, thus far tested, that are substrates for cyclooxygenase or lipoxygenase (i.e., arachidonic, eicosapentaenoic, linoleic and dihomo-gamma-linoleic acids) or which reverse the symptoms of essential fatty acid deficiency (columbinic acid). On the other hand, palmitic, oleic, 5,8,11-eicosatrienoic (n-9, Mead acid), and docosatetraenoic acid (n-6, adrenic acid) were not incorporated in phospholipids by the cytosolic acyltransferase. No such fatty acid selectivity was exhibited by the cytosolic acyl-CoA synthetase or by the acyltransferase activities present in cardiac microsomes and mitochondria.

A functional membrane repair system in Duchenne muscular dystrophy fibroblasts

Experiments have been performed to determine if fibroblasts from patients with Duchenne muscular dystrophy (DMD) are defective in a process of membrane repair. Normal and DMD fibroblasts were treated with phospholipase C from Clostridium perfringens to degrade plasma membrane phosphatidylcholine, and then phosphatidylcholine synthesis was measured as the incorporation of [3H] choline into lipid. Phosphatidylcholine synthesis was stimulated by phospholipase C treatment to a similar extent in normal and DMD fibroblasts. The activity of CTP: phosphocholine cytidylyltransferase, the enzyme regulating phosphatidylcholine synthesis in phospholipase C-treated mammalian cells, was also stimulated to the same extent in both cell types. The subcellular location of the cytidylyltransferase was changed by phospholipase C treatment from mostly cytosolic to mostly particulate in both normal and DMD fibroblasts. It appears, therefore, that at least one type of membrane repair system functions normally in DMD fibroblasts.

Membrane perturbation: studies employing a calcium-sensitive dye, arsenazo III, in liposomes

A metallochromic dye, arsenazo III [2,7-bis-(2-arsonophenylazo)-1,8-dihydroxynaphthalene-3,6-disulfonic acid], has been incorporated into the aquenous interspaces of multilamellar liposomes. multilamellar liposomes. Addition of Ca produced no shift in the absorbance spectrum of dye captured by liposomes, whereas disruption of liposomes by Triton X-100, followed by Ca, produced the spectrum chracteristic of the dye-Ca complex: evidence of latency. Addition of excess ethyleneglycol-bis(beta-aminoethyl ether)-N,N'-tetraacetic acid (EGTA) reversed the spectal shift. Differences between spectra obtained in this sequence yielded dye efflus. To measure Ca efflux, difference spectra (+/-EGTA) were obtained from cationic liposomes containing Ca after detergent lysis (sensitivity less than 10 mmol/ml). Since liposomes were impermeable either to dye or Ca until perturbed, it was possible to test a variety of membrane-active steroids (diethylstilbesterol, deoxycorticosterone, etiocholanolone) for their capacity to provoke dye efflux from liposomes; preincorporation of cortisol stablized liposomes against dye leak. Immunoglobulin-coated liposomes containing dye were taken up by phagocytes of Mustelus canis, and phagocytic vacuoles stained red-purple after ingestions. Liposomes containing the calcium-sensitive dye constitute a simple, accurate means for determining membrane perturbation and Ca fluxes; their uptake by cells or organelles remains to be exploited further.