Interest of rare autoantibodies in autoimmune encephalitis and paraneoplastic neurological syndromes: the utility (or futility) of rare antibody discovery.

PURPOSE OF REVIEW: The increasing recognition and diagnosis of autoimmune encephalitis (AE) and paraneoplastic neurological syndromes (PNS) is partly due to neural autoantibody testing and discovery. The past two decades witnessed an exponential growth in the number of identified neural antibodies. This review aims to summarize recent rare antibody discoveries in the context of central nervous system (CNS) autoimmunity and evaluate the ongoing debate about their utility. RECENT FINDINGS: In the last 5 years alone 15 novel neural autoantibody specificities were identified. These include rare neural antibody biomarkers of autoimmune encephalitis, cerebellar ataxia or other movement disorders, including multifocal presentations. SUMMARY: Although the clinical applications of these rare antibody discoveries may be limited by the low number of positive cases, they still provide important diagnostic, prognostic, and therapeutic insights.

New Insights on DR and DQ Human Leukocyte Antigens in Anti-LGI1 Encephalitis.

BACKGROUND AND OBJECTIVES: To explore the clinical characteristics and HLA associations of patients with anti-leucine-rich glioma-inactivated 1 encephalitis (LGI1E) from a large single center in Israel. Anti-LGI1E is the most commonly diagnosed antibody-associated encephalitic syndrome in adults. Recent studies of various populations reveal significant associations with specific HLA genes. We examined the clinical characteristics and HLA associations of a cohort of Israeli patients. METHODS: Seventeen consecutive patients with anti-LGI1E diagnosed at Tel Aviv Medical Center between the years 2011 and 2018 were included. HLA typing was performed using next-generation sequencing at the tissue typing laboratory of Sheba Medical Center and compared with data from the Ezer Mizion Bone Marrow Donor Registry, containing over 1,000,000 samples. RESULTS: Our cohort displayed a male predominance and median age at onset in the 7th decade, as previously reported. The most common presenting symptom was seizures. Notably, paroxysmal dizziness spells were significantly more common than previously reported (35%), whereas faciobrachial dystonic seizures were found only in 23%. HLA analysis revealed overrepresentation of DRB1*07:01 (OR: 3.18, CI: 20.9 p < 1.e-5) and DRB1*04:02 (OR: 3.8, CI: 20.1 p < 1.e-5), as well as of the DQ allele DQB1*02:02 (OR: 2.8, CI: 14.2 p < 0.0001) as previously reported. A novel overrepresentation observed among our patients was of the DQB1*03:02 allele (OR: 2.3, CI: 6.9 p < 0.008). In addition, we found DR-DQ associations, among patients with anti-LGI1E, that showed complete or near-complete linkage disequilibrium (LD). By applying LD analysis to an unprecedentedly large control cohort, we were able to show that although in the general population, DQB*03:02 is not fully associated with DRB1*04:02, in the patient population, both alleles are always coupled, suggesting the DRB1*04:02 association to be primary to disease predisposition. In silico predictions performed for the overrepresented DQ alleles reveal them to be strong binders of LGI1-derived peptides, similarly to overrepresented DR alleles. These predictions suggest a possible correlation between peptide binding sites of paired DR-DQ alleles. DISCUSSION: Our cohort presents distinct immune characteristics with substantially higher overrepresentation of DRB1*04:02 and slightly lower overrepresentation of DQB1*07:01 compared with previous reports implying differences between different populations. DQ-DR interactions found in our cohort may shed additional light on the complex role of immunogenetics in the pathogenesis of anti-LGI1E, implying a possible relevance of certain DQ alleles and DR-DQ interactions.

Preventing post-stroke dementia. The MARCH Trial. Protocol and statistical analysis plan of a randomized clinical trial testing the safety and efficacy of Maraviroc in post-stroke cognitive impairment.

Background: Current evidence suggest that 25%-33% of stroke-survivors develop post-stroke cognitive impairment (PSCI). The licensed drug Maraviroc, a CCR5-antagonist, is postulated to act via a neuroprotective mechanism that may offer the potential of preventing progression to vascular dementia. Our hypothesis: Maraviroc may have the potential to augment learning skills and cognitive performance by affecting synaptic plasticity, along with neuro-inflammatory modulation in patients with cerebral small vessel disease (SVD) and PSCI. Design: MARCH is a multi-center, double-blind randomized-control Phase-II trial of Maraviroc 150 or 600 mg/day versus placebo for 12-months in five stroke centers in Israel. Included are patients diagnosed with recent (1-24 months) subcortical stroke who experience mild PSCI and have evidence of white matter lesions and SVD on neuroimaging. Outcomes: Primary outcomes: 1. Change in cognitive scores. 2. Drug related adverse events. Secondary outcomes: change in functional and affective scores, MRI-derived measures, inflammatory markers, carotid atherosclerosis, cerebrospinal-fluid biomarkers in a sub-study. A sample size of 60 in each treatment group and 30 in the placebo group (total - 150 participants) provides 80% power between the treatment and the placebo groups. Conclusions: The results of this work could lead to a novel, readily available, therapeutic avenue to reduce PSCI, and possibly other pathologies. This study will test safety and effectiveness of Maraviroc in limiting cognitive deterioration and/or post stroke cognitive impairment in patients with cerebral small vessel disease. Schedule: First-patient first-visit was May 2021. Recruitment to complete in 2023, follow-up to complete in 2024.

The importance of tissue-based assay in the diagnosis of autoimmune encephalitis.

BACKGROUND: The evaluation of autoimmune encephalitis (AIE) usually includes antibody testing with commercial kits capable of detecting only preselected antibodies. A non-antigen-specific assay may help detect other antibodies. In this study, we evaluate the utility and clinical relevance of an immunofluorescence assay (IFA) in the evaluation of AIE. METHODS: Immunofluorescence assay was performed on 1949 patients' serum/CSF between 2017 and 2020 and clinical relevance was designated to each case based on clinical course, suggested criteria and ancillary testing. RESULTS: Sixty-one patients (3.1%) had positive serum IFA, positive CSF, or both. Twenty-eight out of 42 patients who were positive only on IFA were designated as clinically relevant (67%), 8 inconclusive (19%), and 6 non-relevant (14%). Pleocytosis was significantly higher in the clinically relevant cases (74% vs. 20% for non-clinically relevant cases). Encephalopathy was the most common presentation (36%), followed by cerebellar syndrome (32%) and seizures (25%). The initial diagnosis changed due to IFA results in 13/28 (46%) cases and IFA result led to the initiation or modification of treatment in all cases (68% and 43%, respectively). Twenty-five patients were treated with 1st line immunotherapy and 12 with 2nd line immunotherapy, with 92% responding to treatment. Twenty-six clinically relevant patients underwent cancer workup: seven (25%) had confirmed malignancy and three had high suspicion of malignancy (total of 37%). CONCLUSION: Non-antigen-specific assays, such as IFA, can identify antibodies not detected in commercially available kits and therefore are recommended in the evaluation of autoimmune encephalitis.

PD-1-inhibitor-induced PCA-2 (MAP1B) Autoimmunity in a Patient with Renal Cell Carcinoma.

Immune check point inhibitors (ICIs) are a group of anti-cancer pharmacological agents which modify T cell activity in order to potentiate an effective immune response against tumor cells. While these drugs prove extremely potent against several types of malignancies, they may be associated with significant autoimmune adverse events. We report a patient who developed a subacute cerebellar syndrome shortly after starting treatment with nivolumab, a PD-1 inhibitor, for renal clear cell carcinoma, with detectable paraneoplastic PCA-2 antibodies. The tumor specimen stained positively for MAP1B, the antigen of PCA-2. The patient responded well to treatment with glucocorticosteroids. This is the first case to our knowledge of PCA-2 paraneoplastic cerebellar degeneration associated with ICI use, which presents in a patient with a malignancy not typically associated with neurological paraneoplastic phenomena. Treatment with immune checkpoint inhibitors (ICIs) is extremely effective in potentiating an immune response against tumor cells, but bears a substantial risk for the development of autoimmune phenomena, including paraneoplastic neurological syndromes. Increasing use of ICIs is leading to increasing numbers of patients with new-onset neurological symptoms. Awareness of these novel entities will aid in early diagnosis and proper treatment.

Tuftsin-phosphorylcholine attenuate experimental autoimmune encephalomyelitis.

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS) which carries a significant burden of morbidity and mortality. Herein we examine the effects of acute treatment with tuftsin-phosphorylcholine (TPC), a novel immune-modulating helminth derived compound, on a murine model of MS. Experimental autoimmune encephalomyelitis (EAE) mice received acute treatment with TPC showed an improved clinical score and significantly less signs of inflammation and demyelination in CNS tissue compared with vehicle treated EAE mice. Our findings suggest that TPC may provide a beneficial clinical effect in EAE and may therefore have a potential value for ameliorating clinical manifestations and delaying disease progression in MS.

Characteristics of Pericardial Biopsy: 100 Cases in a Single Center.

BACKGROUND: Pericardial biopsies are rarely performed during the diagnosis and management of pericardial diseases. The circumstances and clinical profile of patients undergoing pericardial biopsies are largely uncharacterized. OBJECTIVES: To examine the circumstances in which pericardial biopsies are obtained and to evaluate their diagnostic yield. METHODS: We studied a total of 100 cases (71% males, mean age 60.8 years, range 8.1-84.5 years) of surgically resected pericardium specimens obtained from 2000 to 2015 at Sheba Medical Center, the largest medical center in Israel. Patients were classified into groups according to four major histological etiologies: idiopathic pericarditis, constrictive pericarditis, malignant pericarditis, and post-cardiac injury syndrome (PCIS). The clinical history and course, laboratory, echocardiography, and histological results were reviewed retrospectively. RESULTS: Causes of pericarditis according to histological definitions included idiopathic pericarditis (29%), constrictive pericarditis (29%), PCIS (9%), and malignant pericarditis (26%). Overall sensitivity of the pericardial biopsy in patients with malignancy was 57.7%. During the study period, we found a trend toward an increased number of biopsies due to constrictive pericarditis and PCIS, along with a decrease in the number of biopsies performed in patients with malignant or idiopathic pericarditis. The diagnosis following biopsy did not change for any of the patients. CONCLUSIONS: Our findings suggest a low diagnostic yield from pericardial biopsies, especially in malignant pericarditis. This conclusion, along with novel therapies, resulted in the infrequent use of pericardial biopsy in recent years.

Immunomodulation of Murine Chronic DSS-Induced Colitis by Tuftsin-Phosphorylcholine.

Helminths or their products can immunomodulate the host immune system, and this phenomenon may be applied as the basis of new anti-inflammatory treatments. Previously, we have shown the efficacy of tuftsin-phosphorylcholine (TPC), based on a helminth product, in four animal models of autoimmune diseases: arthritis, colitis, systemic lupus erythematosus, and experimental autoimmune encephalomyelitis. We demonstrated that TPC reduced inflammatory process ex vivo in peripheral blood lymphocytes (PBLs) and in biopsies from giant-cell arteritis. In the present study, we assessed the therapeutic potential of TPC treatment on a chronic colitis murine model. C57BL/6 mice with chronic colitis were treated with TPC after the third cycle of 2% dextran sodium sulfate (DSS). Oral TPC treatment resulted in amelioration of the colitis clinical manifestations exemplified by reduced disease activity index (DAI) score, expansion of mesenteric lymph nodes (MLN) T regulatory cells (shown by Fluorescence Activated Cell Sorting (FACS)), significant reduction in the expression of pro-inflammatory cytokines (IL-1ß, IL17, IL-6, TNFα), and elevation in the expression of anti-inflammatory cytokine IL-10 (shown by RT-PCR). This study demonstrated the potential immunomodulatory effects of oral administration of TPC in a chronic colitis murine model. Further clinical trials are needed in order to evaluate this novel approach for the treatment of patients with inflammatory bowel disease.

Tuftsin phosphorylcholine-a novel compound harnessing helminths to fight autoimmunity.

The distinction that in areas where helminthic infections are common, autoimmune diseases are less prevalent, led to the investigation of immune modulatory properties of helminths and their derivatives. Such are phosphorylcholine (PC) moieties which are a component of secreted products of helminths. PC has been broadly studied for its attenuating effects on the human immune system. In an attempt to develop a novel therapeutic small molecule for the treatment of autoimmune conditions, we have conjugated PC with tuftsin, a natural immunomodulatory tetrapeptide, to create TPC. Herein, we review our findings regarding the effects of TPC in murine models of three autoimmune diseases-systemic lupus erythematosus (SLE), inflammatory bowel disease (IBD), and rheumatic arthritis (RA), as well as ex-vivo samples from giant cell arteritis (GCA) patients. In all four disease models examined, TPC was shown to attenuate the inflammatory response by reducing expression of pro-inflammatory cytokines and altering the phenotype of T cell expression. In murine models, TPC has further produced a significant improvement in clinical disease scores with no significant side effects noted. Our findings suggest TPC presents promising potential as a novel therapeutic agent for the effective treatment of various autoimmune conditions.

Vaccine-induced autoimmunity: the role of molecular mimicry and immune crossreaction.

Since the early 1800s vaccines have saved numerous lives by preventing lethal infections. However, during the past two decades, there has been growing awareness of possible adverse events associated with vaccinations, cultivating heated debates and leading to significant fluctuations in vaccination rates. It is therefore pertinent for the scientific community to seriously address public concern of adverse effects of vaccines to regain public trust in these important medical interventions. Such adverse reactions to vaccines may be viewed as a result of the interaction between susceptibility of the vaccinated subject and various vaccine components. Among the implicated mechanisms for these reactions is molecular mimicry. Molecular mimicry refers to a significant similarity between certain pathogenic elements contained in the vaccine and specific human proteins. This similarity may lead to immune crossreactivity, wherein the reaction of the immune system towards the pathogenic antigens may harm the similar human proteins, essentially causing autoimmune disease. In this review, we address the concept of molecular mimicry and its application in explaining post vaccination autoimmune phenomena. We further review the principal examples of the influenza, hepatitis B, and human papilloma virus vaccines, all suspected to induce autoimmunity via molecular mimicry. Finally, we refer to possible implications on the potential future development of better, safer vaccines.

The value of Autoimmune Syndrome Induced by Adjuvant (ASIA) - Shedding light on orphan diseases in autoimmunity.

Autoimmune Syndrome Induced by Adjuvant (ASIA) is a definition aimed to describe the common etiological process at the root of five clinical entities sharing similar symptomatology: macrophagic myofasciitis syndrome (MMF), Gulf War Syndrome (GWS), sick building syndrome (SBS), siliconosis, and post vaccination autoimmune phenomena. ASIA illustrates the role of environmental immune stimulating agents, or adjuvants, in the instigation of complex autoimmune reactions among individuals bearing a genetic preponderance for autoimmunity. The value of ASIA lies first in the acknowledgment it provides for patients suffering from these as yet ill-defined medical conditions. Equally important is the spotlight it sheds for further research of these poorly understood conditions sharing a common pathogenesis. In this article we elaborate on the significance of ASIA, review the current evidence in support of the syndrome, and address recent reservations raised regarding its validity.

[NOTES FROM A SIX MONTHS VOLUNTEER MISSION AS MEDICAL STAFF IN A DISTRICT HOSPITAL IN UGANDA].

INTRODUCTION: In December 2014 my husband and I flew for a stay of six months in Uganda. We went there in order to volunteer in the district hospital of Kiboga, one of the most impoverished districts of this poverty stricken country. A district in which over 60% of the population lives off less than a dollar and twenty five cents a day, in which the average life expectancy is 46.7 years (9.1 years lower than the national average expectancy). Kiboga's district hospital serves the 300,000 residents of the district, of whom 20,000 live in the district capital, while the rest are mainly farmers and cattle keepers, scattered in small villages that have limited and weather-dependent access. The hospital houses 120 beds, which are divided into four wards (maternity, pediatric, male and female), and is manned routinely by one on-call local physician, who (when present) is almost exclusively occupied by emergency cesarean sections. Therefore, the majority of hospitalized patients are not inspected by a doctor at any point of their stay. The hospital functions with no running water and in the absence of a reliable power supply. The nursing staff, composed largely of people with limited or no training, is always desperately understaffed, and many of the means needed for a patient's stay (starting with a bed pan and linens and ending with many of the medications prescribed) are not supplied by the hospital. Perhaps it would have been appropriate to continue by describing unsettling data about the health infrastructure in Kiboga (such as the fact that infant mortality rate is a staggering 15%, or that nearly 10% of the districts population have HIV), however, it appears to me that it would be more educating to learn from the story of the patients we encountered.

Dietary factors in rheumatic autoimmune diseases: a recipe for therapy?

Today, we are facing a new era of digitization in the health care system, and with increased access to health care information has come a growing demand for safe, cost-effective and easy to administer therapies. Dietary habits have a crucial influence on human health, affecting an individual's risk for hypertension, heart disease and stroke, as well as influencing the risk of developing of cancer. Moreover, an individual's lifestyle choices can greatly influence the progression and manifestation of chronic autoimmune rheumatic diseases. In light of these effects, it makes sense that the search for additional therapies to attenuate such diseases would include investigations into lifestyle modifications. When considering the complex web of factors that influence autoimmunity, it is not surprising to find that several dietary elements are involved in disease progression or prevention. In this Review, several common nutritional components of the human diet are presented, and the evidence for their effects on rheumatic diseases is discussed.

Human papilloma virus and lupus: the virus, the vaccine and the disease.

PURPOSE OF REVIEW: Systemic lupus erythematosus (SLE) is a well known, widespread autoimmune disease, involving multiple organ systems, with a multifaceted, widely unmapped etiopathogenesis. Recently, a new aspect of morbidity has been described among SLE patients: infection with human papilloma virus (HPV). We set out to review data regarding the intricate relationship between the two and attempt to determine whether HPV may pose as a contributing factor to the development of SLE. RECENT FINDINGS: We relate to epidemiological, molecular and clinical data. We have found evidence in all these fields suggesting HPV to be involved in the pathogenesis of SLE: increased prevalence of HPV infection among SLE patients; vast molecular homology between viral peptides and human proteins associated with SLE; several reports of SLE development post-HPV vaccination. Our findings suggest a possible involvement of HPV infection in the induction of SLE, via a mechanism of immune cross-reaction due to molecular homology. SUMMARY: We review clinical, epidemiological and molecular data suggesting involvement of HPV infection in the pathogenesis of SLE. We suggest that these findings may justify the development of new HPV vaccines containing viral peptides that bear no homology to the human proteome, in order to avoid possible adverse immune cross-reactivity.

HPV and systemic lupus erythematosus: a mosaic of potential crossreactions.

Etiology, pathogenesis, and immunology of systemic lupus erythematosus (SLE) form a complex, still undeciphered picture that recently has been further made complicated by a new factor of morbidity: human papillomaviruses (HPVs). Indeed, a prevalence of HPV infections has been reported among SLE patients. Searching for molecular mechanisms that might underlie and explain the relationship between HPV infection and SLE, we explored the hypothesis that immune responses following HPV infection may crossreact with proteins that, when altered, associate with SLE. Analyzing HPV L1 proteins and using Epstein-Barr virus (EBV) and human retrovirus (HERV) as controls, we found a vast peptide overlap with human proteins comprehending lupus Ku autoantigen proteins p86 and p70, lupus brain antigen 1 homolog, lupus antigen expressed in neurons and muscles, natural killer cell IgG-like receptors, complement proteins C4-A and C4-B, complement receptor CD19, and others. The multitude and heterogeneity of peptide overlaps not only further support the hypothesis that crossreactivity can represent a primum movens in SLE onset, but also provide a molecular framework to the concept of SLE as "an autoimmune mosaic syndrome." Finally, once more, it emerges the need of using the principle of peptide uniqueness as a new paradigm for safe and efficacious vaccinology.