The Social and Home Environment: Impacts of Determinants of Health on Atopic Dermatitis, Pathways Toward Solutions, and Unique Considerations for Rural and Remote North American Indigenous Populations

Disparities in environmental and social determinants of health (DOH) are associated with morbidity in atopic dermatitis (AD). The socioecological model (SEM) is a framework that can be applied to better understand how such DOH impacts patients with AD. We include a case scenario of a remote Indigenous patient reflective of real-world situations of living with AD and examine relevant impact, gaps in knowledge, and further research needs. This review highlights a variety of social and environmental exposures as important DOH which must be addressed to achieve optimal management in AD. The "rainbow model" is a modified framework to help illustrate how complex environmental and social forces impact both AD presentation and therapeutic success. However, practical applications and outcome metrics for health promotion are limited. An inter- and transdisciplinary approach is paramount to address the complex challenges associated with AD care, as well as multistakeholder approach integrating culturally-competent equitable health frameworks. This review underscores the importance of expanding the focus of AD management beyond basic science and clinical trials to recognize and address health disparities and to promote optimal health and well-being in patients with AD, and contributes a working approach to mapping the complex interventions and patient-oriented research needed using a focus on remote North American Indigenous patients affected by AD.

Mental health interventions for atopic dermatitis: knowledge gaps, pilot programmes and future directions

Atopic dermatitis (AD) is associated with high levels of psychosocial burden, often resulting in poor mental health outcomes. Despite this association, few studies have evaluated the efficacy of mental health interventions within this population. Utilization of multidisciplinary and peer-led support, in addition to equipping patients with psychological tools, may be beneficial in improving mental health outcomes. Future research is needed to determine which interventions and formats are desired by, effective in and accessible to patients and caregivers with AD.

A concept for integrated care pathways for atopic dermatitis-A GA2 LEN ADCARE initiative

INTRODUCTION

The integrated care pathways for atopic dermatitis (AD-ICPs) aim to bridge the gap between existing AD treatment evidence-based guidelines and expert opinion based on daily practice by offering a structured multidisciplinary plan for patient management of AD. ICPs have the potential to enhance guideline recommendations by combining interventions and aspects from different guidelines, integrating quality assurance, and describing co-ordination of care. Most importantly, patients can enter the ICPs at any level depending on AD severity, resources available in their country, and economic factors such as differences in insurance reimbursement systems.

METHODS

The GA2 LEN ADCARE network and partners as well as all stakeholders, abbreviated as the AD-ICPs working group, were involved in the discussion and preparation of the AD ICPs during a series of subgroup workshops and meetings in years 2020 and 2021, after which the document was circulated within all GAL2 EN ADCARE centres.

RESULTS

The AD-ICPs outline the diagnostic procedures, possible co-morbidities, different available treatment options including differential approaches for the pediatric population, and the role of the pharmacists and other stakeholders, as well as remaining unmet needs in the management of AD.

CONCLUSION

The AD-ICPs provide a multidisciplinary plan for improved diagnosis, treatment, and patient feedback in AD management, as well as addressing critical unmet needs, including improved access to care, training specialists, implementation of educational programs, assessment on the impact of climate change, and fostering a personalised treatment approach. By focusing on these key areas, the initiative aims to pave the way for a brighter future in the management of AD.

Oral prednisone regulates human skin T cells in delayed-type hypersensitivity reaction elicited by diphencyprone

BACKGROUND

The potential benefit of inducing delayed-type hypersensitivity (DTH) reaction in healthy volunteers (HVs) as experimental models to study skin inflammatory disorders was recently reported using bulk molecular technologies. Immunophenotype of skin T cells, including cellular source of Type 1, 2, and 3 cytokines, in a local DTH reaction and their modulation by oral drugs remain to be investigated.

METHOD

Purified protein derivative (PPD), nickel, diphencyprone (DPCP), or house dust mite (HDM) was administered as sensitizer to 40 HVs. In addition, 20 HVs were randomized to receive oral prednisone or placebo before DPCP challenge. We characterized the immunophenotype and cytokine profile of CD3⁺ T cell infiltrate, and examined the modulation by oral prednisone at single cell level using multi-parameter flow cytometry and unsupervised analysis.

RESULTS

PPD was biased towards a Th1 and Tc1 response, and HDM a Th2/Th17 and Tc2. Nickel and DPCP displayed a mixed Th1/Th2/Th17 and Tc1 response. CD4⁺ CD25⁺ FoxP3⁺ regulatory T cells (Tregs), the minor CD4⁺ CD25⁺ FoxP3^- ICOS⁺ PD-1⁺ (activated PD-1⁺ Th), and CD103⁺ tissue resident memory (TRM) cells were detected in all groups. DPCP uniquely elicited rare CD8⁺ CD103⁺ CD25⁺ RoRγt⁺ PD-1⁺ ICOS⁺ IFNγ⁺ T cells (activated CD8⁺ IFNγ⁺ PD-1⁺ TRM). Oral prednisone decreased frequencies of activated PD-1⁺ Th and CD8⁺ IFNγ⁺ PD-1⁺ TRM subsets relative to placebo in DPCP reaction. The latter was positively correlated with improvement of clinical parameters with prednisone.

CONCLUSION

DTH and skin CD3⁺ T cell profiles elicited by common sensitizers can be modulated by oral drugs. Corticosteroids reduce the frequencies of activated PD-1⁺ Th and CD8⁺ IFNγ⁺ PD-1⁺ TRM cells after DPCP exposure.

Tapinarof for psoriasis and atopic dermatitis: 15 years of clinical research

Tapinarof is a topical, aryl-hydrocarbon receptor agonist that has recently received FDA-approval for the treatment of psoriasis. This novel therapeutic has also been shown to be effective for atopic dermatitis and is currently in phase 3 for this indication. Beyond good efficacy and fast onset of action in patients with psoriasis, the clinical response to tapinarof is notable for durable remission or near remission, maintained for an average of 130 days beyond treatment discontinuation in patients with psoriasis in phase 3 studies. Tapinarof is usually well tolerated but can induce a follicular inflammatory reaction and dermatitis in some patients. This narrative review covers the historical development of this molecule, safety and efficacy data from clinical trials conducted with various topical formulations, and practical considerations derived from our 15 years of clinical trial experience with the drug.

Delayed type hypersensitivity reactions to various allergens may differently model inflammatory skin diseases

BACKGROUND

Treatment of inflammatory skin diseases, including atopic dermatitis (AD) and psoriasis, is undergoing transformative changes, highlighting the need to develop experimental models of skin inflammation in humans to predict treatment responses.

METHODS

We topically or intradermally administered four common sensitizers (dust mite (DM), diphencyprone (DPCP), nickel (Ni), and purified protein derivative (PPD)) to the backs of 40 healthy patients and the skin hypersensitivity response was biopsied and evaluated using immunohistochemistry, RNA-seq, and RT-PCR.

RESULTS

All agents induced strong increases in cellular infiltrates (T-cells and dendritic cells) as compared to untreated skin (p < .05), with variable T helper polarization. Overall, DPCP induced the strongest immune responses across all pathways, including innate immunity (IL-1α, IL-8), Th1 (IFNγ, CXCL10), Th2 (IL-5, CCL11), and Th17 (CAMP/LL37) products, as well as the highest regulatory tone (FOXP3, IL-34, IL-37) (FDR <0.01). Nickel induced Th17 (IL-17A), Th1 (CXCL10) and Th2 (IL-4R) immune responses to a lesser extent than DPCP (p < .05). PPD induced predominantly Th1 (IFNγ, CXCL10, STAT1) and Th17 inflammation (IL-17A) (p < .05). DM induced modulation of Th2 (IL-13, CCL17, CCL18), Th22 (IL-22), and Th17/Th22 (S100A7/9/12) pathways (p < .05). Barrier defects that characterize both AD and psoriasis were best modeled by DPCP and Ni, followed by PPD, including downregulation of terminal differentiation (FLG, FLG2, LOR, LCEs), tight junction (CLDN1/CLDN8), and lipid metabolism (FA2H, FABP7)-related markers.

CONCLUSION

Our data imply that DPCP induced the strongest immune response across all pathways, and barrier defects characteristic of AD and psoriasis.

Treatment Guidelines for Atopic Dermatitis Since the Approval of Dupilumab: A Systematic Review and Quality Appraisal Using AGREE-II

Introduction

Since its approval for adults with moderate-to-severe atopic dermatitis (AD) in 2017, dupilumab has been incorporated into clinical practice guidelines (CPGs). However, recommendations differ internationally, and the quality assessment of their development is unclear.

Objective

We aimed to systematically review and appraise the quality of CPGs for adult AD reported since 2017 and map the recommendations for dupilumab initiation relative to conventional systemic therapy (CST).

Materials and Methods

A literature search was conducted in June 2020 in MEDLINE, EMBASE, SCOPUS, and CINAHL. Twelve CPGs were retrieved. Methodological quality was assessed using the validated Appraisal of Guidelines for Research & Evaluation II tool (AGREE-II). Recommendations were extracted and compared.

Results

AGREE-II median scores per domain of the CPGs were (%, r = range): scope/purpose, 78% (50-96); stakeholder involvement, 54% (28-85); rigor of development, 39% (21-63); clarity of presentation, 85% (69-100); applicability, 27% (6-51); and editorial independence, 76% (42-100). Neither met the threshold of 70% quality criteria for rigor of development nor the applicability domains. Three CPGs met the criteria for recommendation without modification. CPGs' approach to dupilumab initiation was as follows: second line, preferred over CST and nbUVB (n = 1/12 CPG); second line, equivalent to CST or nbUVB (n = 3/12 CPGs); third line, after nbUVB or CST (n = 5/12 CPGs); and fourth line after nbUVB and CST (n = 2/12). No consensus was reached for n = 1/12 CPG.

Conclusion and Relevance

Dupilumab is now incorporated into CPGs for adult AD. These CPGs exhibited good quality in scope/purpose, clarity, and editorial independence domains. However, none met AGREE-II criteria for methodological rigor/applicability. Gaps were found in mechanisms for updates, facilitators/barriers, resource implications, and stakeholder involvement. Only n = 3/12 CPGs met quality criteria for recommendation without modifications. Of these, two favored a conservative sequential approach for the initiation of dupilumab relative to CST, while one did not reach consensus. Our findings highlight divergent recommendations AD treatment, underlining a need to incorporate quality criteria into future guideline development.

Vascular inflammation in moderate-to-severe atopic dermatitis is associated with enhanced Th2 response

BACKGROUND

In atopic dermatitis (AD), some studies have shown an association with increased cardiovascular disease in certain populations. However, other investigations found modest or no association. Despite conflicting results, molecular profiling studies in both AD skin and blood have demonstrated upregulation of atherosclerosis and cardiovascular risk-related markers. However, the underlying mechanisms connecting AD to vascular inflammation/atherosclerosis are unknown. In this study, we aim to determine factors associated with vascular inflammation/atherosclerosis in AD patients.

METHODS

We used 18-FDG PET-CT to characterize vascular inflammation in AD patients and healthy subjects. In parallel, we assessed their skin and blood immune profiles to determine AD-related immune biomarkers associated with vascular inflammation. We also assessed levels of circulating microparticles, which are known to be associated with increased cardiovascular risk.

RESULTS

We found significant correlations between vascular inflammation and Th2-related products in skin and blood of AD patients as well as atherosclerosis-related markers that were modulated by dupilumab. Circulating levels of endothelial microparticles were significantly higher in severe AD patients and tended to correlate with vascular inflammation assessed by PET-CT.

CONCLUSION

Vascular inflammation in AD is associated with enhanced Th2 response and clinical severity, which may explain cardiovascular comorbidities observed in select AD populations. Larger prospective studies are needed to further evaluate vascular inflammation and cardiovascular events and mortality in AD patients. Finally, as dupilumab treatment demonstrated significant modulation of atherosclerosis-related genes in AD patients compared to placebo, these data suggest that modulation of vascular inflammation with systemic treatment should be explored in patients with AD.

Practical Management of Patients with Atopic Dermatitis on Dupilumab

INTRODUCTION

Dupilumab is approved to treat moderate-to-severe atopic dermatitis (AD) in several countries in patients as young as 6 years of age. Since its approval, practical issues related to the use of dupilumab for AD have arisen, with particular interest in transitioning from current therapies and managing medication overlap, considerations for special populations of patients with AD, and management of potential adverse events.

METHODS

This article aims to review the literature addressing several practical management issues related to dupilumab use for AD and to provide a framework for clinical decision-making in these circumstances and sub-populations. Each statement was reviewed, revised and voted on by authors to provide their level of agreement and degree of uncertainty for each statement.

RESULTS

An agreement level > 80% was achieved for all of the statements.

CONCLUSION

The expert panel provides statements considering the practical management of patients with AD taking dupilumab to inform clinical decision-making in specific but frequently encountered clinical situations.

Measuring Atopic Dermatitis Disease Severity: The Potential for Electronic Tools to Benefit Clinical Care

Severity of atopic dermatitis (AD) correlates with impact on health-related quality of life (HRQoL), work productivity, and burden on health systems. Tools to measure severity inform regulatory approval, drug access, and value- or measurement-based care. A core set of instruments for measuring AD has been established. Clinician-reported tools are divided broadly into multi-item global estimates or precise calculators that also weigh affected corporeal surfaces. Increasingly, subjective patient-reported outcomes are valued, with the potential to capture vast amounts of health-related data. Patient-reported outcomes can be disease-agnostic, skin-related, or AD-specific, and evaluate global disease, itch severity, long-term control, or overall HRQoL. Patient-reported outcomes are expansive in number; therefore, item banks and adaptive digital user interfaces will be increasingly needed, along with capacity to store and analyze data. Technologies for AD include tools for communication, severity assessment, or data exchange, as well as electronic health records (EHRs). For clinicians, a limited number of applications exist, with relatively poor interoperability with EHRs to date. For patients, a growing number of mobile health (mHealth) applications exhibit variable compliance with international guidelines for self-management. Data privacy and information security governance are key considerations in the development of information technologies for AD. Integrated and streamlined digital operational processes for disease measurements may build capacity for high value and efficient care of patients with AD across the globe.

Key actors in driving behavioural change in relation to on-farm biosecurity; a Northern Ireland perspective

Background

Agriculture and farming are valued contributors to local economy in Northern Ireland (NI). There is limited knowledge about farmers’ behaviours and attitudes towards disease biosecurity measures. As part of a larger project, a scenario-based workshop with key stakeholders was organised by the Agri-Food and Biosciences Institute (AFBI)-NI in December 2015.

Results

A total of 22 participants belonging to 12 different institutions took part in the workshop. Participants were presented with an overview of previously conducted biosecurity research in NI and England. In small groups, participants were subsequently asked to discuss and give their opinions about a series of questions across four key areas in a semi-structured approach with an external facilitator. The key areas were 1- disease risk perception at the farm level; 2-perceived barriers to implementing on farm biosecurity measures; 3- avenues to successful behaviour change and 4-key industry responsibilities and roles. The discussion showed that training in biosecurity for farmers is important and necessary. Training was recommended to be provided by veterinary surgeons, preferably via a face-to-face format. The discussion addressing disease disclosure proved particularly challenging between those who were prospective buyers of cattle, and those who sold cattle.

Conclusions

This workshop provided a unique and invaluable insight into key issues regarding farm level biosecurity activities. From a policy perspective, delivering improved on-farm biosecurity must be addressed via a multidisciplinary approach. This can only be achieved with active involvement, commitment and support of a number of key industry and government stakeholders.

Electronic supplementary material

The online version of this article (10.1186/s13620-018-0125-1) contains supplementary material, which is available to authorized users.

Preclinical trials in autosomal dominant AD: implementation of the DIAN-TU trial

The Dominantly Inherited Alzheimer's Network Trials Unit (DIAN-TU) was formed to direct the design and management of interventional therapeutic trials of international DIAN and autosomal dominant Alzheimer's disease (ADAD) participants. The goal of the DIAN-TU is to implement safe trials that have the highest likelihood of success while advancing scientific understanding of these diseases and clinical effects of proposed therapies. The DIAN-TU has launched a trial design that leverages the existing infrastructure of the ongoing DIAN observational study, takes advantage of a variety of drug targets, incorporates the latest results of biomarker and cognitive data collected during the observational study, and implements biomarkers measuring Alzheimer's disease (AD) biological processes to improve the efficiency of trial design. The DIAN-TU trial design is unique due to the sophisticated design of multiple drugs, multiple pharmaceutical partners, academics servings as sponsor, geographic distribution of a rare population and intensive safety and biomarker assessments. The implementation of the operational aspects such as home health research delivery, safety magnetic resonance imagings (MRIs) at remote locations, monitoring clinical and cognitive measures, and regulatory management involving multiple pharmaceutical sponsors of the complex DIAN-TU trial are described.

MR imaging features of amyloid-related imaging abnormalities

BACKGROUND AND PURPOSE

AD is one of the few leading causes of death without a disease-modifying drug; however, hopeful agents are in various phases of development. MR imaging abnormalities, collectively referred to as amyloid-related imaging abnormalities, have been reported for several agents that target cerebral Aβ burden. ARIA includes ARIA-E, parenchymal or sulcal hyperintensities on FLAIR indicative of parenchymal edema or sulcal effusions, and ARIA-H, hypointense regions on gradient recalled-echo/T2* indicative of hemosiderin deposition. This report describes imaging characteristics of ARIA-E and ARIA-H identified during studies of bapineuzumab, a humanized monoclonal antibody against Aβ.

MATERIALS AND METHODS

Two neuroradiologists with knowledge of imaging changes reflective of ARIA reviewed MR imaging scans from 210 bapineuzumab-treated patients derived from 3 phase 2 studies. Each central reader interpreted the studies independently, and discrepancies were resolved by consensus. The inter-reader κ was 0.76, with 94% agreement between neuroradiologists regarding the presence or absence of ARIA-E in individual patients.

RESULTS

Thirty-six patients were identified with incident ARIA-E (17.1%, 36/210) and 26 with incident ARIA-H (12.4%, 26/210); of those with incident ARIA-H, 24 had incident microhemorrhages and 2 had incident large superficial hemosiderin deposits.

CONCLUSIONS

In 49% of cases of ARIA-E, there was the associated appearance of ARIA-H. In treated patients without ARIA-E, the risk for incident blood products was 4%. This association between ARIA-E and ARIA-H may suggest a common pathophysiologic mechanism. Familiarity with ARIA should permit radiologists and clinicians to recognize and communicate ARIA findings more reliably for optimal patient management.

Something's missing here: a look at the quality of rheumatology referral letters

A convincing body of evidence points to an early window of opportunity for the treatment of rheumatoid arthritis. However, data indicate that in many cases, this window of opportunity is missed. Once a patient does present to their primary care provider, important additional delays in rheumatology assessment can occur. To report the results of our study assessing referral letters to rheumatologists, we examined referral letters received over a one-year period by one full-time rheumatologist practicing at a tertiary-care center. We found only a small percentage of referral letters made mention of the pattern of joint involvement. Just 17% of consults indicated symptom duration. Only 2% mentioned any circadian rhythm of symptoms (such as morning stiffness), and only 6% provided information about functional status. Almost two-thirds (62%) of consults specified only 'joint pain' in the referral letter. We provide objective evidence that referral letters sent to rheumatologists are often lacking in key elements of the medical history. This lack of information means that appropriate triage of referrals by rheumatologists is very difficult. As a response to this, we have developed, with family physicians and rheumatologists, a standardized referral template which is being pilot-tested. Our ultimate goal is to improve wait times for patients with urgent conditions such as inflammatory arthritis.

Long-term results of a hydroxyapatite-coated femoral component in total hip replacement: a 15- to 21-year follow-up study

Between 1986 and 1991 we implanted 331 consecutive Furlong hydroxyapatite-coated femoral components of a total hip replacement in 291 patients. A cemented acetabular prosthesis was used in 217 hips and a hydroxyapatite-coated component in 114. We describe the long-term clinical and radiological survival of the femoral component at a mean follow-up of 17.5 years (15 to 21). Only two patients (0.68%) were lost to follow-up. With revision of the femoral component for any reason as the endpoint, the survival at a mean of 17 years was 97.4% (95% confidence interval 94.1 to 99.5), and with revision for aseptic loosening as the endpoint it was 100%. The survival at a maximum of 21 years with revision of the femoral component for any reason as the endpoint was 97.4% (95% confidence interval 81.0 or 99.5). These results compare favourably with the best long-term results of cemented or uncemented femoral components used in total hip replacement.

Contrasting potential of nitric oxide and peroxynitrite to mediate oligodendrocyte injury in multiple sclerosis

Nitric oxide (NO) and peroxynitrite (ONOO(-)) are potential mediators of the injury and cytotoxicity occurring over time to oligodendrocytes in multiple sclerosis (MS) lesions. Our in vitro results indicate that human adult CNS-derived oligodendrocytes are relatively resistant to NO-mediated damage. In contrast, human oligodendrocytes are highly susceptible to peroxynitrite-mediated injury. In situ, we found that inducible nitric oxide synthase (iNOS) was expressed in astrocytes and macrophages in all active demyelinating and remyelinating MS lesions examined, yet no correlation was found between numbers of glial cells expressing iNOS and the extent of oligodendrocyte cell death. Nitrotyrosine groups, indicative of the presence of peroxynitrite in vivo, could be detected on astrocytes, macrophages, and oligodendrocytes in MS lesions. High numbers of nitrotyrosine-positive oligodendrocytes were found in one MS case that featured extensive oligodendrocyte cell death. Our results indicate that NO alone is unlikely to induce oligodendrocyte injury, whereas its more potent byproduct peroxynitrite is a potential mediator of injury to oligodendrocytes in MS.

Microglial expression of the B7 family member B7 homolog 1 confers strong immune inhibition: implications for immune responses and autoimmunity in the CNS

Inflammation of the CNS is usually locally limited to avoid devastating consequences. Critical players involved in this immune regulatory process are the resident immune cells of the brain, the microglia. Interactions between the growing family of B7 costimulatory ligands and their receptors are increasingly recognized as important pathways for costimulation and/or inhibition of immune responses. Human and mouse microglial cells constitutively express B7 homolog 1 (B7-H1) in vitro. However, under inflammatory conditions [presence of interferon-gamma (IFN-gamma) or T-helper 1 supernatants], a significant upregulation of B7-H1 was detectable. Expression levels of B7-H1 protein on microglial cells were substantially higher compared with astrocytes or splenocytes. Coculture experiments of major histocompatibility complex class II-positive antigen-presenting cells (APC) with syngeneic T cells in the presence of antigen demonstrated the functional consequences of B7-H1 expression on T-cell activation. In the presence of a neutralizing anti-B7-H1 antibody, both the production of inflammatory cytokines (IFN-gamma and interleukin-2) and the upregulation of activation markers (inducible costimulatory signal) by T cells were markedly enhanced. Interestingly, this effect was clearly more pronounced when microglial cells were used as APC, compared with astrocytes or splenocytes. Furthermore, B7-H1 was highly upregulated during the course of myelin oligodendrocyte glycoprotein-induced and proteolipid protein-induced experimental allergic encephalomyelitis in vivo. Expression was predominantly localized to areas of strongest inflammation and could be colocalized with microglial cells/macrophages as well as T cells. Together, our data propose microglial B7-H1 as an important immune inhibitory molecule capable of downregulating T-cell activation in the CNS and thus confining immunopathological damage.

Expression of the immune-tolerogenic major histocompatibility molecule HLA-G in multiple sclerosis: implications for CNS immunity

HLA-G is a non-classical major histocompatibility complex (MHC) class I antigen with highly limited tissue distribution under non-pathological conditions. Although capable of acting as a peptide-presenting molecule, its strong immune-inhibitory properties identify HLA-G as a mediator of immune tolerance with specific relevance at immune-privileged sites such as trophoblast or thymus. To assess the role of HLA-G in CNS immunity, we investigated its expression in brain specimens from patients with multiple sclerosis (n = 11), meningitis (n = 2) and Alzheimer's disease (n = 2) and non-pathological CNS controls (n = 6). Furthermore, cultured human microglial cells and CSF of patients with multiple sclerosis and controls were assessed. Furthermore, CSF from MS patients and controls, as well as cultured human microglial cells were assessed. Using several HLA-G specific mAb and immunohistochemistry, HLA-G protein was found strongly expressed in brain specimens from patients with multiple sclerosis while it was rarely detectable in the non-pathological control specimens. In multiple sclerosis brain specimens, HLA-G immunoreactivity was observed in acute plaques, in chronic active plaques, in perilesional areas as well as in normal appearing white matter. In all areas microglial cells, macrophages, and in part endothelial cells were identified as the primary cellular source of expression. HLA-G was also found in other disease entities (meningitis, Alzheimer's specimens) where expression correlated to activation and MHC class II expression on microglial cells. Importantly, ILT2, a receptor for HLA-G, was also found in multiple sclerosis brain specimens thus emphasizing the relevance of this inhibitory pathway in vivo. HLA-G mRNA and protein expression and regulation could also be corroborated on cultured human microglial cells in vitro. Further, expression of HLA-G in the CSF of multiple sclerosis patients and controls was analysed by flow cytometry and ELISA. Monocytes represented the main source of cellular HLA-G expression in the CSF. Corresponding to the observations with the tissue specimens, CSF mean levels of soluble HLA-G were significantly higher in multiple sclerosis than in non-inflammatory controls (171 +/- 31 versus 39 +/- 10 U/ml; P = 0.0001). The demonstration of HLA-G and its receptor ILT2 on CNS cells and in areas of microglia activation implicate HLA-G as a contributor to the fundamental mechanisms regulating immune reactivity in the CNS. This pathway may act as an inhibitory feedback aimed to downregulate the deleterious effects of T-cell infiltration in neuroinflammation.

Microglia and multiple sclerosis

Microglia participate in all phases of the multiple sclerosis (MS) disease process. As members of the innate immune system, these cells have evolved to respond to stranger/danger signals; such a response within the central nervous system (CNS) environment has the potential to induce an acute inflammatory response. Engagement of Toll-like receptors (TLRs), a major family of pattern-recognition receptors (PRRs), provides an important mechanism whereby microglia can interact with both exogenous and endogenous ligands within the CNS. Such interactions modulate the capacity of microglia to present antigens to cells of the adaptive immune system and thus contribute to the initiation and propagation of the more sophisticated antigen-directed responses. This inflammatory response introduces the potential for bidirectional feedback between CNS resident and infiltrating systemic cells. Such interactions acquire particular relevance in the era of therapeutics for MS because the infiltrating cells can be subjected to systemic immunomodulatory therapies known to change their functional properties. Phagocytosis by microglia/macrophages is a hallmark of the MS lesion; however, the extent of tissue damage and the type of cell death will dictate subsequent innate responses. Microglia/macrophages are armed with a battery of effector molecules, such as reactive nitrogen species, that may contribute to CNS tissue injury, specifically to the injury of oligodendrocytes that is associated with MS. A therapeutic challenge is to modulate the dynamic properties of microglia/macrophages so as to limit potentially damaging innate responses, to protect the CNS from injury, and to promote local recovery.

Mild cognitive impairment--beyond controversies, towards a consensus: report of the International Working Group on Mild Cognitive Impairment

The First Key Symposium was held in Stockholm, Sweden, 2-5 September 2003. The aim of the symposium was to integrate clinical and epidemiological perspectives on the topic of Mild Cognitive Impairment (MCI). A multidisciplinary, international group of experts discussed the current status and future directions of MCI, with regard to clinical presentation, cognitive and functional assessment, and the role of neuroimaging, biomarkers and genetics. Agreement on new perspectives, as well as recommendations for management and future research were discussed by the international working group. The specific recommendations for the general MCI criteria include the following: (i) the person is neither normal nor demented; (ii) there is evidence of cognitive deterioration shown by either objectively measured decline over time and/or subjective report of decline by self and/or informant in conjunction with objective cognitive deficits; and (iii) activities of daily living are preserved and complex instrumental functions are either intact or minimally impaired.

Mild cognitive impairment--beyond controversies, towards a consensus: report of the International Working Group on Mild Cognitive Impairment

The First Key Symposium was held in Stockholm, Sweden, 2-5 September 2003. The aim of the symposium was to integrate clinical and epidemiological perspectives on the topic of Mild Cognitive Impairment (MCI). A multidisciplinary, international group of experts discussed the current status and future directions of MCI, with regard to clinical presentation, cognitive and functional assessment, and the role of neuroimaging, biomarkers and genetics. Agreement on new perspectives, as well as recommendations for management and future research were discussed by the international working group. The specific recommendations for the general MCI criteria include the following: (i) the person is neither normal nor demented; (ii) there is evidence of cognitive deterioration shown by either objectively measured decline over time and/or subjective report of decline by self and/or informant in conjunction with objective cognitive deficits; and (iii) activities of daily living are preserved and complex instrumental functions are either intact or minimally impaired.