Staying connected: An umbrella review of meta-analyses on the push-and-pull of social connection in depression

BACKGROUND

Depression affects approximately 4 % of the global population and has huge social and economic implications. Social factors, including support, engagement, and stigma, play a crucial role in the development and severity of depression.

METHODS

We provide a synthesis of the consistency and magnitude of the association between measures of social connection and depression. We searched PubMed, PsycINFO, Cochrane Library, and EMBASE and 47 meta-analyses were included in the umbrella review. The strength of the associations was extracted and compared among different populations. The quality/certainty of evidence was assessed using AMSTAR-2 and GRADE tool.

RESULTS

Results indicate that social support serves as a protective factor against depression, particularly in peripartum populations, while its impact is weaker in clinical populations. No association was found between social support and depression in post-disaster populations. Stigma and discrimination favour the development and maintenance of depressive symptoms in clinical populations, but have a weaker effect in ethnic minorities.

LIMITATIONS

The quality and certainty of evidence should be taken into account when interpreting our findings. Further research with more rigorous methodology and higher-quality evidence is needed to better understand the complex relationship between depression and social connection across various populations and contexts.

CONCLUSIONS

Our findings confirm the role of social determinants in the emergence and severity of depression, particularly in the case of vulnerable populations. Efforts to counteract disconnection at the societal and individual levels and to reduce stigma should be central to an effective depression prevention agenda.

Bdnf-Nrf-2 crosstalk and emotional behavior are disrupted in a sex-dependent fashion in adolescent mice exposed to maternal stress or maternal obesity

Maternal obesity has been recognized as a stressor affecting the developing fetal brain, leading to long-term negative outcomes comparable to those resulting from maternal psychological stress, although the mechanisms have not been completely elucidated. In this study, we tested the hypothesis that adverse prenatal conditions as diverse as maternal stress and maternal obesity might affect emotional regulation and stress response in the offspring through common pathways, with a main focus on oxidative stress and neuroplasticity. We contrasted and compared adolescent male and female offspring in two mouse models of maternal psychophysical stress (restraint during pregnancy - PNS) and maternal obesity (high-fat diet before and during gestation - mHFD) by combining behavioral assays, evaluation of the hypothalamic-pituitary-adrenal (HPA) axis reactivity, immunohistochemistry and gene expression analysis of selected markers of neuronal function and neuroinflammation in the hippocampus, a key region involved in stress appraisal. Prenatal administration of the antioxidant N-acetyl-cysteine (NAC) was used as a strategy to protect fetal neurodevelopment from the negative effects of PNS and mHFD. Our findings show that these two stressors produce overlapping effects, reducing brain anti-oxidant defenses (Nrf-2) and leading to sex-dependent impairments of hippocampal Bdnf expression and alterations of the emotional behavior and HPA axis functionality. Prenatal NAC administration, by restoring the redox balance, was able to exert long-term protective effects on brain development, suggesting that the modulation of redox pathways might be an effective strategy to target common shared mechanisms between different adverse prenatal conditions.

The predictive role of proinflammatory and neuroendocrine factors in the acute phases of bipolar disorder: study protocol of a longitudinal controlled trial

INTRODUCTION AND AIMS

Bipolar disorder (BD) is a severe and recurring mental illness associated with a significant personal and social burden. It has been recently hypothesized that increased levels of pro-inflammatory cytokines and cortisol, which is also associated with a reduced expression of the brain-derived neurotrophic factor (BDNF), may influence affective recurrences in BD. Our study aims to: 1) assess changes in the levels of peripheral cytokines, BDNF and salivary cortisol during acute and euthymic phases of bipolar disorder, compared to that of a sample oh healthy controls; 2) evaluate whether these changes represent a biosignature for the different phases of the illness.

MATERIALS AND METHODS

Patients aged 18-65 years old, with a diagnosis of BD I or II types, will be enrolled during an acute episode, according to DSM-5 criteria, together with age- and gender-matched healthy controls. Blood and salivary samples will be collected at baseline and after 3 and 6 months. Validated assessment instruments will be administered to all participants for the evaluation of symptom severity, global functioning, suicidal risk, stress levels and physical comorbidities.

EXPECTED RESULTS

We expect changes in inflammatory and neuroendocrine indices to be predictive of the onset of an acute phase of bipolar disorder and that overall levels of cytokines, cortisol and BDNF are overall significantly different between BD patients and healthy controls.

CONCLUSIONS

The longitudinal design of the study will allow to assess whether the presence of acute affective symptoms in BD patients correlates with significantly higher levels of cytokines and salivary cortisol and with reduced BDNF levels compared to euthymic phases. Moreover, the comparison with healthy control subjects will allow to understand if inflammatory mediators as well as the hypothalamic-pituitary-adrenal (HPA) axis are chronically elevated in BD patients and are independent from mood swings.

Reduction in the use of green spaces during the COVID-19 pandemic and its impact on mental health

Our study examined the use of green spaces before and during the pandemic in a large cohort of Italian twins and evaluated its impact on measures of mental health (depressive, anxiety, stress symptoms). Twins were analysed as individuals and as pairs. A twin design approach was applied to minimize confounding by genetic and shared environmental factors. Questionnaires from 2,473 twins enrolled in the Italian Twin Registry were screened. Reduced green space use was associated with significantly higher levels of depression, anxiety and distress. Being a woman, residing in urban areas, and having a high perceived risk of the outbreak resulted in a higher likelihood to modify green space use, with a negative impact on mental health.

Rosmarinic Acid Improves Cognitive Abilities and Glucose Metabolism in Aged C57Bl/6N Mice While Disrupting Lipid Profile in Young Adults in a Sex-Dependent Fashion

A growing body of evidence suggests that regular consumption of natural products might promote healthy aging; however, their mechanisms of action are still unclear. Rosmarinic acid (RA) is a polyphenol holding anti-inflammatory, antioxidant and neuroprotective properties. The aim of this study was to characterise the efficacy of an oral administration of RA in promoting healthspan in a mouse model of physiological aging. Aged C57Bl/6 male and female (24-month-old) mice were either administered with RA (500 mg/Kg) or a vehicle in drinking bottles for 52 days while 3-month-old mice receiving the same treatment were used as controls. All subjects were assessed for cognitive abilities in the Morris water maze (MWM) and for emotionality in the elevated-plus maze test (EPM). Brain-derived Neurotrophic Factor (BDNF) protein levels were evaluated in the hippocampus. Since the interaction between metabolic signals and cerebral functions plays a pivotal role in the etiopathogenesis of cognitive decline, the glycaemic and lipid profiles of the mice were also assessed. RA enhanced learning and memory in 24-month-old mice, an effect that was associated to improved glucose homeostasis. By contrast, the lipid profile was disrupted in young adults. This effect was associated with worse glycaemic control in males and with reduced BDNF levels in females, suggesting powerful sex-dependent effects and raising a note of caution for RA administration in young healthy adult subjects.

Using sport-based interventions for people with severe mental disorders: results from the European EASMH study

People with severe mental disorders report significantly poorer physical health and a higher mortality rate compared with the general population. Several interventions have been proposed in order to challenge this mortality gap, the promotion of physical activities represents one of the most important strategies. In fact, in people with severe mental disorders, physical activity can improve body composition, quality of life, personal functioning, self-esteem, cognition, and cardiorespiratory fitness, as well as reducing affective, psychotic and anxiety symptoms, cardiometabolic burden and increase the global recovery. While sport-based programs are consistently being proposed as an integral part of effective personalized treatment approaches for people with severe mental disorders, their routine implementation is hampered by poor working task integration among different professionals and the lack of training programmes for sport professionals focused on people with severe mental disorders. In this paper, we will: (a) review the efficacy of exercise/sport-based interventions for people with severe mental disorders; (b) describe the main difficulties in engaging patients with severe mental disorders in these interventions; and (c) report the results of the first study on the best practices available in Europe in the field of sport and mental health carried out in the context of the European Alliance for Sport and Mental Health (EASMH) project. According to the EASMH survey, sport-based psychosocial interventions are not frequently available in mental health services, with significant differences at the European level. In the near future, it would be advisable to promote the integration and collaboration between mental health professionals and sport professionals, in order to improve the dissemination and availability of sport-based interventions in routine clinical practice. The EASMH project aims to fill this gap by creating a network of collaborators, researchers and stakeholders with different backgrounds in order to improve the dissemination of sport-based rehabilitation interventions and by developing an innovative training programme for sport coaches in order to improve their skills in interacting and building an effective relationship with people with severe mental disorders.

Dissemination of sport-based psychosocial interventions in Europe: results from the EASMH project

Introduction

Among psychosocial interventions, recent studies have highlighted that sport-based interventions can positively impact on the long-term outcomes of patients with severe mental disorders, in terms of improving their quality of life and promoting social inclusion. Although sport-based interventions should be considered an effective strategy for promoting patients’ recovery, few data are available on their dissemination in the clinical routine care in Europe.

Objectives

to evaluate the availability of sport-based psychosocial interventions in European countries.

Methods

In the framework of the EU-Erasmus+, the European Alliance for Sport and Mental Health (EASMH) project has been funded. In order to evaluate the availability of sport-based interventions, an ad-hoc online survey, sent to national mental health centres, has been developed.

Results

103 responses were obtained (49 from Italy, 31 from UK, 17 from Finland and 12 from Romania). The respondents were mainly psychiatrists working in community mental health centers. Sport-based interventions were frequently provided by mental health services, in particular in Italy, UK and Finland. While in UK and Finland sport-based interventions are commonly offered to all patients, in the other countries these are provided only by patient’s request. The most frequent types of sport practised were: running, football, volleyball, tennis and table tennis and basketball. Almost all respondents reported to not use a dedicated monitoring tool for evaluating the efficacy of those interventions.

Conclusions

Sport-based interventions are not frequently provided in the routine clinical settings, although no monitoring tools are routinely adopted. The EASMHaims to fill this gap by disseminating good clinical practice related to sport-based interventions.

Disclosure

No significant relationships.

Improving the Emotional Distress and the Experience of Hospitalization in Children and Adolescent Patients Through Animal Assisted Interventions: A Systematic Review

Introduction

Animal Assisted Interventions (AAIs) are increasingly common in pediatric care settings as a means to promote the physical, mental, and emotional well-being of hospitalized children and adolescents.

Objectives

The aim of this work was to review published studies implementing AAIs in hospital settings and to assess the effects of AAIs on the biobehavioral response to stress and pain, social behavior, quality of life and level of satisfaction with hospitalization in children and adolescents. Stress and burden, quality of life, mood and level of satisfaction with hospitalization in parents/caregivers as well as stress and burden, perception of the work environment and job satisfaction in hospital staff were also reviewed.

Methods

All published studies reporting quantitative assessments were systematically searched using PubMed, Scopus, ProQuest and Web of Science databases in accordance with PRISMA guidelines. The aim was to identify studies examining the effects of AAIs on behavioral, psychological and physiological responses to stress in children and adolescents (0-18 years) formally admitted to a hospital for a stay, as well as in those undergoing a visit for treatments or medical examinations.

Results

Of the 350 studies screened, 21 were eligible for inclusion. Most of them focused on stress, pain, and anxiety reduction in pediatric patients, and used both physiological parameters and behavioral and psychological observations/scales. All studies employed dogs. Results show the potential of AAIs to reduce anxiety and behavioral distress in pediatric patients while acting on physiological measures associated with arousal.

Conclusion

Although further, more rigorous studies are still needed, the findings of this review may have implications for clinical practices suggesting appropriate planning of AAIs by pediatric healthcare professionals.

Systematic Review Registration

[https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=178993], identifier [CRD42020178993].

Chronic Isolation Stress Affects Central Neuroendocrine Signaling Leading to a Metabolically Active Microenvironment in a Mouse Model of Breast Cancer

Social isolation is a powerful stressor capable of affecting brain plasticity and function. In the case of breast cancer, previous data indicate that stressful experiences may contribute to a worse prognosis, activating neuroendocrine and metabolism pathways, although the mechanisms underlying these effects are still poorly understood. In this study, we tested the hypothesis that chronic isolation stress (IS) may boost hypothalamic–pituitary–adrenal (HPA) axis activity, leading to changes in the hypothalamic expression of genes modulating both mood and metabolism in an animal model of breast cancer. This centrally activated signaling cascade would, in turn, affect the mammary gland microenvironment specifically targeting fat metabolism, leading to accelerated tumor onset. MMTVNeuTg female mice (a model of breast cancer developing mammary hyperplasia at 5 months of age) were either group-housed (GH) or subjected to IS from weaning until 5 months of age. At this time, half of these subjects underwent acute restraint stress to assess corticosterone (CORT) levels, while the remaining subjects were characterized for their emotional profile in the forced swimming and saccharin preference tests. At the end of the procedures, all the mice were sacrificed to assess hypothalamic expression levels of Brain-derived neurotrophic factor (Bdnf), Neuropeptide Y (NpY), Agouti-Related Peptide (AgRP), and Serum/Glucocorticoid-Regulated Protein Kinase 1 (SgK1). Leptin and adiponectin expression levels, as well as the presence of brown adipose tissue (BAT), were assessed in mammary fat pads. The IS mice showed higher CORT levels following acute stress and decreased expression of NpY, AgRP, and SgK1, associated with greater behavioral despair in the forced swimming test. Furthermore, they were characterized by increased consumption of saccharin in a preference test, suggesting an enhanced hedonic profile. The IS mice also showed an earlier onset of breast lumps (assessed by palpation) accompanied by elevated levels of adipokines (leptin and adiponectin) and BAT in the mammary fat pads. Overall, these data point to IS as a pervasive stressor that is able to specifically target neuronal circuits, mastered by the hypothalamus, modulating mood, stress reactivity and energy homeostasis. The activation of such IS-driven machinery may hold main implications for the onset and maintenance of pro-tumorigenic environments.

Equine-Assisted Interventions (EAIs) for Children with Autism Spectrum Disorders (ASD): Behavioural and Physiological Indices of Stress in Domestic Horses (Equus caballus) during Riding Sessions

Equine-assisted interventions (EAIs) are well-known complementary practices combining physical activity with emotional/cognitive stimulation. They are especially suited for children with autism spectrum disorders (ASD) who need a high degree of physical and psychological enrichment. Even though EAIs have become a common practice, stress responses in horses interacting with individuals that can manifest inappropriate behaviours, such as ASD children, have not been thoroughly investigated. Our multicentre study aimed to investigate behavioural and physiological indices of stress in horses involved in EAI standardised sessions with children with ASD compared to typically developing (TD) children. A controlled within-subject design with repeated measurements involving 19 horses and 38 children was adopted. Stress-related behaviours, heart rate, heart rate variability, and eye temperature were recorded during the riding sessions. Moreover, blood samples were collected from horses before and after each session to monitor changes in blood adrenocorticotropic hormone (ACTH), cortisol, and catecholamines. Results indicate that, in general, stress responses in horses involved in EAIs did not differ as a function of the horse being ridden by children with ASD or TD. A lower sympathetic tone in horses involved in ASD sessions was found, while in the mounting and dismounting phases, horses displayed behavioural signs of stress, independently from children's behaviour. We conclude that professionals working in EAI should increase their awareness of animal welfare and refine riding practices, taking into account horse's needs.

Equestrian vaulting as an innovative complementary intervention in eating disorders: A pilot study

Introduction

Anorexia is a disorder associated with severe disturbances in eating behaviors and related thoughts and emotions (distorted weight perception, body dissatisfaction). Multidimensional integrative treatment approaches are needed to act both on intrapersonal (e.g. nutritional and psychological) and interpersonal (e.g. behavioral and affective) processes.

Objectives

Aim of this pilot project was to develop a 3-months horse-assisted intervention based on Equestrian Vaulting (EV) and tests its suitability and acceptability in patients with anorexia nervosa. Preliminary observations were carried out to assess the effectiveness of this program on body image, interpersonal relationships and communication and in managing anxiety.

Methods

Seven patients in charge of public service specialized in eating disorder participated in the study. EV activities were performed in an Equestrian Centre included horse grooming, gym exercises and horseback sessions.Clinical and psychological tests (SF 36, IPAQ, EDI3, STAI, SCL90) were administered at baseline and at the end of the program.

Results

Increases in body fat and decreases in lean muscle mass were observed. These were accompained by an improvement in participants’ anxiety and relational skills and in the specific disease related symptoms.

Conclusions

Results indicate the potential of EV to help patients with eating disorder regaining awareness of themselves and their body, a critical element for their future reintegration in the contexts of everyday life and society. Although this is a pilot, the protocol developed represents an initial step to promote the application of EV in persons with eating disorders, informing feasibility in the design of larger controlled studies and suggesting critical variables to be targeted.

Improving hospitalization in children and adolescents through animal assisted interventions (AAIS): A systematic review

Introduction

Animal Assisted Interventions (AAIs) are increasingly introduced in pediatric care settings as a mean to promote the physical, mental, and emotional well-being of hospitalized children and adolescents and the humanization of the hospital environment.

Objectives

The aim of this work was to review published studies implementing AAIs in hospital settings and to assess their effectiveness in reducing stress and pain, ameliorating social behavior, quality of life, and mood in pediatric patients. Reviewed interventions were also evaluated for their effects on caregiver’s stress and burden, as well as on perception of the work environment in hospital staff.

Methods

Studies were systematically searched using PubMed, Scopus, ProQuest and Web of Science databases in accordance with PRISMA guidelines. The search was aimed at identifying studies examining the effects of AAIs on behavioral and physiological response to stress in children and adolescents (0-18 years) formally admitted to a hospital for a stay, as well as in those undergoing a visit for treatments or medical examinations.

Results

Of 350 studies screened, 17 were eligible for inclusion. Most of them focused on stress, pain and anxiety reduction in pediatric patients, and used both physiological parameters and behavioral observations/scales. The vast majority of the studies employed dogs. Results show the potential of AAIs to reduce anxiety and behavioral distress in pediatric patients, while acting on physiological measures associated with arousal.

Conclusions

Although further studies of better quality are still needed, the findings of this review may have implications for clinical practices suggesting appropriate planning of AAIs by pediatric healthcare professionals.

N-acetyl-cysteine administration during foetal life improves social behaviour and restores hippocampal bdnf levels in adolescent mice prenatally exposed to a high-fat diet

Introduction

Maternal obesity may affect foetal programming representing a risk for adult mental health. Oxidative stress and inflammation associated with maternal obesity can alter the maturation of neuronal circuits affecting behaviour and mood.

Objectives

We investigated the emotional phenotype of male and female mouse offspring born from a high-fat diet (HFD) fed dams. We also tested the efficacy of N-acetyl-cysteine (NAC – an antioxidant) in preventing the negative effects of HFD. We focused on adolescence, an age of main vulnerability for the onset of psychopathology.

Methods

Female C57BL/6N mice were fed HFD for 13 weeks and, after 5 weeks, were also exposed to NAC (1 g/kg b.w.) via drinking water, until delivery. The neurodevelopment of offspring was assessed through the homing test. Emotionality was assessed in 35-45-day-old adolescent mice through elevated-plus-maze (EPM) and social interaction tests (SIT). Transcriptomic analysis of hippocampal tissue were performed to identify mechanisms of action of both HFD and NAC.

Results

NAC was effective in moderating body weight gain in HFD-fed dams. Neither HFD or NAC affected offspring development. Regardless of sex, prenatal HFD reduced exploration and decreased sociability, in EPM and SIT respectively. Prenatal HFD decreased hippocampal levels of BDNF in female offspring. Prenatal NAC administration prevented social anxiety and restored BDNF levels in the HFD group.

Conclusions

Data indicate long-term effects of maternal obesity on dams’ weight, offspring’s behaviour and hippocampal BDNF levels. These effects may be mediated by changes in oxidative stress as NAC was effective as a preventive agent. ERANET-NEURON-JTC 2018 (Mental Disorders) Project “EMBED”.

Stress and coping in women with breast cancer:unravelling the mechanisms to improve resilience

Breast cancer diagnosis, surgery, adjuvant therapies and survivorship can all be extremely stressful. In women, concerns about body image are common as a result of the disease and can affect interpersonal relationships, possibly leading to social isolation, increasing the likelihood for mood disorders. This is particularly relevant as women are at greater risk to develop anxiety and depressive symptoms in response to highly stressful situations. Here we address the mechanisms and the pathways activated as a result of stress and contributing to changes in the pathophysiology of breast cancer, as well as the potential of stress management factors and interventions in buffering the deleterious effects of chronic stress in a gender perspective. An improved understanding of the biological mechanisms linking stress-management resources to health-relevant biological processes in breast cancer patients could reveal novel therapeutic targets and help clarifying which psychosocial interventions can improve cancer outcomes, ultimately offering a unique opportunity to improve contemporary cancer treatments.

Social farming as an innovative approach to promote mental health, social inclusion and community engagement

Nature-based contextual factors are being recognized as fundamental for mental health prevention and promotion. Rural areas, indeed, are increasingly recognized as an elective place for the promotion of mental health. In recent years there has been a surge of rurally-based hybrid governance models in which public bodies, local communities and economic actors join forces to create innovative welfare solutions to facilitate the financial (and organizational) challenges faced by the National Health Systems. Using agricultural resources, such as animals and plants, social farming is able to address specific social needs, including rehabilitation, sheltered employment, life-long education and other activities that contribute to social inclusion. At the same time social farming is able to strengthen the economic and social viability of rural communities. We have been studying the factors underlying the potentiality of social farms to provide job placement programs and rehabilitation for people with mental disorders. Using novel methodologies and appropriate tools, we have been collecting data indicating the positive effects of farming activities on individual's social functioning, as well as the impact of farms' networking on system's sustainability.

Dog Visiting Programs for Managing Depressive Symptoms in Older Adults: A Meta-Analysis

BACKGROUND AND OBJECTIVES

Depressive symptoms are highly prevalent in older adults and may contribute to functional impairment at old age. Animal-assisted interventions (AAIs), including interventions involving dog visiting, are increasingly recognized as an innovative approach to ameliorate social, behavioral, psychological, and physical outcomes among older adults. However, available data on their potential to manage depressive symptoms in the aging population are not clear cut. The aim of this review was to conduct a meta-analysis of all prospective controlled studies evaluating the effects of dog visiting on depressive symptoms in older adults.

RESEARCH DESIGN AND METHODS

A comprehensive literature search was conducted on the electronic databases PubMed and Scopus. Included articles were published between 1980 and 2017 and report controlled empirical studies of dog visiting interventions to ameliorate depressive symptoms in older adults.

RESULTS

There was substantial heterogeneity between included studies, which varied in their methodological quality, sample size, and other key features. Notwithstanding such methodological variety, results all go in the same direction and indicate a large beneficial effect of interventions involving dog visiting on depressive symptoms.

DISCUSSION AND IMPLICATIONS

This analysis confirms the potential value of dog visiting in ameliorating depressive symptoms in institutionalized and noninstitutionalized older adults. This is in line with previous research indicating AAIs as promising complementary programs for preserving/enhancing emotional and behavioral function in aged individuals. More research is still needed to allow AAIs to be effectively introduced in clinical practice.

HIV-Tat immunization induces cross-clade neutralizing antibodies and CD4(+) T cell increases in antiretroviral-treated South African volunteers: a randomized phase II clinical trial

BACKGROUND

Although combined antiretroviral therapy (cART) has saved millions of lives, it is incapable of full immune reconstitution and virus eradication. The transactivator of transcription (Tat) protein is a key human immunodeficiency virus (HIV) virulence factor required for virus replication and transmission. Tat is expressed and released extracellularly by infected cells also under cART and in this form induces immune dysregulation, and promotes virus reactivation, entry and spreading. Of note, anti-Tat antibodies are rare in natural infection and, when present, correlate with asymptomatic state and reduced disease progression. This suggested that induction of anti-Tat antibodies represents a pathogenesis-driven intervention to block progression and to intensify cART. Indeed Tat-based vaccination was safe, immunogenic and capable of immune restoration in an open-label, randomized phase II clinical trial conducted in 168 cART-treated volunteers in Italy. To assess whether B-clade Tat immunization would be effective also in patients with different genetic background and infecting virus, a phase II trial was conducted in South Africa.

METHODS

The ISS T-003 was a 48-week randomised, double-blinded, placebo-controlled trial to evaluate immunogenicity (primary endpoint) and safety (secondary endpoint) of B-clade Tat (30 μg) given intradermally, three times at 4-week intervals, in 200 HIV-infected adults on effective cART (randomised 1:1) with CD4(+) T-cell counts ≥200 cells/µL. Study outcomes also included cross-clade anti-Tat antibodies, neutralization, CD4(+) T-cell counts and therapy compliance.

RESULTS

Immunization was safe and well-tolerated and induced durable, high titers anti-Tat B-clade antibodies in 97 % vaccinees. Anti-Tat antibodies were cross-clade (all vaccinees tested) and neutralized Tat-mediated entry of oligomeric B-clade and C-clade envelope in dendritic cells (24 participants tested). Anti-Tat antibody titers correlated positively with neutralization. Tat vaccination increased CD4(+) T-cell numbers (all participants tested), particularly when baseline levels were still low after years of therapy, and this had a positive correlation with HIV neutralization. Finally, in cART non-compliant patients (24 participants), vaccination contained viral load rebound and maintained CD4(+) T-cell numbers over study entry levels as compared to placebo.

CONCLUSIONS

The data indicate that Tat vaccination can restore the immune system and induces cross-clade neutralizing anti-Tat antibodies in patients with different genetic backgrounds and infecting viruses, supporting the conduct of phase III studies in South Africa. Trial registration ClinicalTrials.gov NCT01513135, 01/23/2012.

HIV-1 tat promotes integrin-mediated HIV transmission to dendritic cells by binding Env spikes and competes neutralization by anti-HIV antibodies

Use of Env in HIV vaccine development has been disappointing. Here we show that, in the presence of a biologically active Tat subunit vaccine, a trimeric Env protein prevents in monkeys virus spread from the portal of entry to regional lymph nodes. This appears to be due to specific interactions between Tat and Env spikes that form a novel virus entry complex favoring R5 or X4 virus entry and productive infection of dendritic cells (DCs) via an integrin-mediated pathway. These Tat effects do not require Tat-transactivation activity and are blocked by anti-integrin antibodies (Abs). Productive DC infection promoted by Tat is associated with a highly efficient virus transmission to T cells. In the Tat/Env complex the cysteine-rich region of Tat engages the Env V3 loop, whereas the Tat RGD sequence remains free and directs the virus to integrins present on DCs. V2 loop deletion, which unshields the CCR5 binding region of Env, increases Tat/Env complex stability. Of note, binding of Tat to Env abolishes neutralization of Env entry or infection of DCs by anti-HIV sera lacking anti-Tat Abs, which are seldom present in natural infection. This is reversed, and neutralization further enhanced, by HIV sera containing anti-Tat Abs such as those from asymptomatic or Tat-vaccinated patients, or by sera from the Tat/Env vaccinated monkeys. Thus, both anti-Tat and anti-Env Abs are required for efficient HIV neutralization. These data suggest that the Tat/Env interaction increases HIV acquisition and spreading, as a mechanism evolved by the virus to escape anti-Env neutralizing Abs. This may explain the low effectiveness of Env-based vaccines, which are also unlikely to elicit Abs against new Env epitopes exposed by the Tat/Env interaction. As Tat also binds Envs from different clades, new vaccine strategies should exploit the Tat/Env interaction for both preventative and therapeutic interventions.

A combination HIV vaccine based on Tat and Env proteins was immunogenic and protected macaques from mucosal SHIV challenge in a pilot study

HIV native Tat and V2 loop-deleted Env (EnvΔV2) proteins already proved safe and immunogenic in phase I clinical testing as single vaccine components. Further, a phase II vaccine trial with Tat showed intensification of the therapeutic effects of HAART in successfully treated HIV-infected individuals. Here a pilot study assessed the immunogenicity and protective efficacy of an HIV/AIDS vaccine based on the combination of Tat and EnvΔV2 proteins in cynomolgus macaques against homologous intrarectal challenge with 35 MID(50) (monkey infectious dose 50) of an R5 simian-human immunodeficiency virus (SHIV(SF162P4cy)). Upon challenge, three of four macaques immunized with Tat and EnvΔV2, and two of three monkeys immunized with EnvΔV2 alone were protected from infection. In contrast, all three control animals, which had been either administered with the adjuvants only or left untreated, and an additional monkey immunized with Tat alone became systemically infected. Protection of the macaques vaccinated with EnvΔV2 or Tat/EnvΔV2 correlated with higher peak titers of pre-challenge neutralizing antibodies obtained during the immunization period (between 70 and 3 weeks before challenge) and with anti-Env V3 loop binding antibodies assessed 3 weeks before challenge. Compared to EnvΔV2 alone, the Tat and EnvΔV2 combined vaccine elicited faster antibody responses (IgM) with a trend, early in the vaccination schedule, after the second immunization including EnvΔV2, towards broader anti-Env IgG epitope specificity and a higher ratio of neutralizing to Env-binding antibody titers. As the number of immunizations increased, vaccination with EnvΔV2 approached the immune response assessed after two inocula with the Tat/EnvΔV2 combined vaccine, even though some differences remained between groups, as indicated by anti-Env IgG epitope mapping. In fact, three weeks before challenge, plasma IgG of animals in the EnvΔV2 group showed a trend towards stronger specificity for the V1 loop and V5 loop-C5 regions of Env, whereas the Tat/EnvΔV2 group displayed an overall higher reactivity for epitopes within the Env V3 loop throughout the immunization period. Although differences in terms of protection rate were not found between the EnvΔV2 or Tat/EnvΔV2 vaccination groups in this pilot study, vaccination with Tat/EnvΔV2 appeared to accelerate the induction of potentially protective antibody responses to Env. In particular, antibodies to the Env V3 loop, whose levels at pre-challenge correlated with protection, were already higher early in the vaccination schedule in monkeys immunized with Tat/EnvΔV2 as compared to EnvΔV2 alone. Further studies including larger vaccination groups and fewer immunizations with these two vaccine candidates are needed to confirm these findings and to assess whether the Tat/EnvΔV2 vaccine may afford superior protection against infection.

Parallel conduction of the phase I preventive and therapeutic trials based on the Tat vaccine candidate

The native HIV-1 Tat protein was chosen as vaccine candidate for phase I clinical trials in both uninfected (ClinicalTrials.gov identifier: NCT00529698) and infected volunteers (ClinicalTrials.gov identifier: NCT00505401). The rationale was based on the role of Tat in the natural infection and AIDS pathogenesis, on the association of Tat-specific immune responses with the asymptomatic stage and slow-progression rate as well as on its sequence conservation among HIV clades (http://www.hiv1tat-vaccines.info/). The parallel conduction in the same clinical centers of randomized, double blind, placebo-controlled phase I studies both in healthy, immunologically competent adults and in HIV-infected, clinically asymptomatic, individuals represents a unique occasion to compare the vaccine-induced immune response in both the preventive and therapeutic setting. In both studies, the same lot of the native Tat protein was administered 5 times, every four weeks, subcute (SC) with alum adjuvant or intradermic (ID), in the absence of adjuvant, at 7.5 microg, 15 microg or 30 microg doses, respectively. The primary and secondary endpoints of these studies were the safety and immunogenicity of the vaccine candidate, respectively. The study lasted 52 weeks and monitoring was conducted for on additional 3 years. The results of both studies indicated that the Tat vaccine is safe and well tolerated both locally and systemically and it is highly immunogenic at all the dosages and by both routes of administration. Vaccination with Tat induced a balanced immune response in uninfected and infected individuals. In particular, therapeutic immunization induced functional antibodies and partially reverted the marked Th1 polarization of anti-Tat immunity seen in natural infection, and elicited a more balanced Th1/Th2 immune response. Further, the number of CD4 T cells correlated positively with anti-Tat antibody titers. Based on these results, a phase II study is ongoing in infected drug-treated individuals (http://www.hiv1tat-vaccines.info/).

The Presence of Anti‐Tat Antibodies Is Predictive of Long‐Term Nonprogression to AIDS or Severe Immunodeficiency: Findings in a Cohort of HIV‐1 Seroconverters

The human immunodeficiency virus (HIV) type 1 Tat protein plays a key role in the life cycle of the virus and in pathogenesis and is highly conserved among HIV subtypes. On the basis of this and of safety, immunogenicity, and efficacy findings in monkeys, Tat is being tested as a vaccine in phase 1 trials. Here, we evaluated the incidence and risk of progression to advanced HIV disease by anti-Tat serostatus in a cohort of 252 HIV-1 seroconverters. The risk of progression was lower in the anti-Tat-positive subjects than in the anti-Tat-negative subjects. Progression was faster in the persistently anti-Tat-negative subjects than in the transiently anti-Tat-positive subjects, and no progression was observed in the persistently anti-Tat-positive subjects.

Sequence Conservation and Antibody Cross‐Recognition of Clade B Human Immunodeficiency Virus (HIV) Type 1 Tat Protein in HIV‐1–Infected Italians, Ugandans, and South Africans

We determined immune cross-recognition and the degree of Tat conservation in patients infected by local human immunodeficiency virus (HIV) type 1 strains. The data indicated a similar prevalence of total and epitope-specific anti-Tat IgG in 578 serum samples from HIV-infected Italian (n=302), Ugandan (n=139), and South African (n=137) subjects, using the same B clade Tat protein that is being used in vaccine trials. In particular, anti-Tat antibodies were detected in 13.2%, 10.8%, and 13.9% of HIV-1-infected individuals from Italy, Uganda, and South Africa, respectively. Sequence analysis results indicated a high similarity of Tat from the different circulating viruses with BH-10 Tat, particularly in the 1-58 amino acid region, which contains most of the immunogenic epitopes. These data indicate an effective cross-recognition of a B-clade laboratory strain-derived Tat protein vaccine by individuals infected with different local viruses, owing to the high similarity of Tat epitopes.

Lymphomononuclear cells from multiple sclerosis patients spontaneously produce high levels of oncostatin M, tumor necrosis factors alpha and beta, and interferon gamma

Proinflammatory cytokines are deemed to play a pivotal role in the pathogenesis of multiple sderosis (MS). They provide signals for T-cell activation and inflammatory cell recruitment in the brain and might directly alter neuroglial and neuronal cell survival and function. We found that peripheral blood mononuclear cells (PBMCs) from MS patents spontaneously produce high levels of TNFalpha, TNFbeta, IFNgamma, and oncostatin M (oncM), a proinflammatory cytokine actng on cells of neural, vascular, hematopoietic, and lymphoid origin. Spontaneous production of these cytokines was significantly higher (p < 0.01) in PBMC short-term culture supernatants from MS patients than in blood donors (HC). On average, lectin-induced production of these cytokines by PBMC was higher in MS patents than in HC significantly so only for TNFalpha (p = 0.013). Determination of TNFalpha, TNFbeta IFNgamma, and oncM in corresponding sera showed that on average, oncM levels were higher in MS patients than in HC, though the results were not statistically significant whereas levels of TNFalpha, TNFbeta and IFNgamma were below the assay threshold in most patients. The finding that MS PBMCs are primed in vivo to produce and release high levels of proinflammatory cytokines suggests the presence of a basal activation of the immune system which, in turn, may play a role in the complex circuitry of molecular and cellular interactions responsible for neurologic damage in MS.

Endogenous cytokine production protects T cells from spontaneous apoptosis during highly active antiretroviral therapy

BACKGROUND

The availability of therapeutic regimens that effectively interfere with HIV-1 replication provides novel opportunities to investigate mechanisms of T-cell depletion as well as repopulation in infected individuals.

METHODS

Nineteen HIV-1-infected individuals were investigated during one-year follow-up of highly active retroviral therapy (HAART). The frequencies of apoptotic T cells, as determined by propidium iodide, staining, TUNEL assay and analysis of annexin V, were assessed either in the absence or in the presence of anti-interleukin (IL)2 and anti-IL-4 neutralizing Ab. Spontaneous and lectin-induced cytokine production were assessed by ELISA.

RESULTS

Increments of both naive and memory CD4 and CD8 T cells during HAART are accompanied by a decrease of T-cell apoptosis that, after 12 months of HAART, reaches normal levels. This is associated with increments of both spontaneous and activation-induced production of IL-2 and IL-4 by peripheral blood mononuclear cells (PBMCs), though only the latter was found defective at enrolment. During HAART, blocking of either IL-2 or IL-4 production by PBMCs using neutralizing Ab restores levels of T-cell apoptosis consistent with those determined at enrolment. These data suggest that both IL-2 and IL-4 produced by PBMCs during HAART provide anti-apoptotic signals that can contribute to an increased survival of T cells and may thus play a part in long-term immune reconstitution.

CONCLUSIONS

An effective viral suppression and, possibly, effects of PI on molecular targets other than viral components, can support a progressive normalization of T-cell survival that, at least in part, depends upon the restoration of proper soluble signals. These results provide evidence of a supporting role of endogenous cytokine production in peripheral T-cell repopulation during an effective and prolonged viral suppression. This may be relevant for the definition of immune-intervention targets aimed at immune reconstitution in HIV-1-infected patients.