Antigen-specific T cells and autoimmunity.

Autoimmune diseases (ADs) showcase the intricate balance between the immune system's protective functions and its potential for self-inflicted damage. These disorders arise from the immune system's erroneous targeting of the body's tissues, resulting in damage and disease. The ability of T cells to distinguish between self and non-self-antigens is pivotal to averting autoimmune reactions. Perturbations in this process contribute to AD development. Autoreactive T cells that elude thymic elimination are activated by mimics of self-antigens or are erroneously activated by self-antigens can trigger autoimmune responses. Various mechanisms, including molecular mimicry and bystander activation, contribute to AD initiation, with specific triggers and processes varying across the different ADs. In addition, the formation of neo-epitopes could also be implicated in the emergence of autoreactivity. The specificity of T cell responses centers on the antigen recognition sequences expressed by T cell receptors (TCRs), which recognize peptide fragments displayed by major histocompatibility complex (MHC) molecules. The assortment of TCR gene combinations yields a diverse array of T cell populations, each with distinct affinities for self and non-self antigens. However, new evidence challenges the traditional notion that clonal expansion solely steers the selection of higher-affinity T cells. Lower-affinity T cells also play a substantial role, prompting the "two-hit" hypothesis. High-affinity T cells incite initial responses, while their lower-affinity counterparts perpetuate autoimmunity. Precision treatments that target antigen-specific T cells hold promise for avoiding widespread immunosuppression. Nevertheless, detection of such antigen-specific T cells remains a challenge, and multiple technologies have been developed with different sensitivities while still harboring several drawbacks. In addition, elements such as human leukocyte antigen (HLA) haplotypes and validation through animal models are pivotal for advancing these strategies. In brief, this review delves into the intricate mechanisms contributing to ADs, accentuating the pivotal role(s) of antigen-specific T cells in steering immune responses and disease progression, as well as the novel strategies for the identification of antigen-specific cells and their possible future use in humans. Grasping the mechanisms behind ADs paves the way for targeted therapeutic interventions, potentially enhancing treatment choices while minimizing the risk of systemic immunosuppression.

Mesenchymal Stromal Cells from Human Wharton's Jelly Modulate the Intraocular Immune Response in a Glucocorticoid Hypertension Model: An Exploratory Analysis.

INTRODUCTION: Glaucoma is a neurodegenerative disease characterized by the loss of retinal ganglion cells. Recent research suggests immunological changes such as cytokine imbalance may affect its pathophysiology. This implies that immunomodulation, like that of mesenchymal cells, could be a potential therapeutic avenue for this disease. However, the effects of intravitreal injections of human Wharton's jelly-derived mesenchymal stromal cells (hWJ-MSCs) on intraocular immune response have not been assessed in ocular hypertension (OH) models. METHODS: We explored this by measuring cytokine levels and expression of other markers, such as glial fibrillary acidic protein (GFAP) and T cells, in 15 randomly divided New Zealand rabbits: G1: OH, G2: hWJ-MSCs, and G3: OH+hWJ-MSCs. We analyzed the aqueous humor (IL-6, IL-8, and TNF-α) and vitreous humor (IFN-γ, IL-10, and TGF-ß) using ELISA and flow cytometry (cell populations), as well as TCD3+, TCD3+/TCD4+, and TCD3+/TCD8+ lymphocytes, and GFAP in the retina and optic nerve through immunohistochemistry. RESULTS: We found a decrease in TNF-α, IL-6, IFN-γ, IL-10, and IL-8 in G3 compared to G1 and an increase in TGF-ß in both G2 and G3. TCD3+ retinal infiltration in all groups was primarily TCD8+ rather than TCD4+ cells, and strong GFAP expression was observed in both the retina and optic nerves in all groups. CONCLUSION: Our results suggest that cellular and humoral immune responses may play a role in glaucomatous optic neuropathy and that intravitreal hWJ-MSCs can induce an immunosuppressive environment by inhibiting proinflammatory cytokines and enhancing regulatory cytokines.

Molecular mimicry and autoimmunity in the time of COVID-19.

Infectious diseases are commonly implicated as potential initiators of autoimmune diseases (ADs) and represent the most commonly known factor in the development of autoimmunity in susceptible individuals. Epidemiological data and animal studies on multiple ADs suggest that molecular mimicry is one of the likely mechanisms for the loss of peripheral tolerance and the development of clinical disease. Besides molecular mimicry, other mechanisms such as defects in central tolerance, nonspecific bystander activation, epitope-determinant spreading, and/or constant antigenic stimuli, may also contribute for breach of tolerance and to the development of ADs. Linear peptide homology is not the only mechanism by which molecular mimicry is established. Peptide modeling (i.e., 3D structure), molecular docking analyses, and affinity estimation for HLAs are emerging as critical strategies when studying the links of molecular mimicry in the development of autoimmunity. In the current pandemic, several reports have confirmed an influence of SARS-CoV-2 on subsequent autoimmunity. Bioinformatic and experimental evidence support the potential role of molecular mimicry. Peptide dimensional analysis requires more research and will be increasingly important for designing and distributing vaccines and better understanding the role of environmental factors related to autoimmunity.

Persistent Autoimmune Activation and Proinflammatory State in Post-Coronavirus Disease 2019 Syndrome.

BACKGROUND: The immunopathological pathways enabling post-coronavirus disease 2019 (COVID-19) syndrome (PCS) development are not entirely known. We underwent a longitudinal analysis of patients with COVID-19 who developed PCS aiming to evaluate the autoimmune and immunological status associated with this condition. METHODS: Thirty-three patients were included for longitudinal clinical and autoantibody analyses, 12 of whom were assessed for cytokines and lymphocyte populations. Patients were followed for 7-11 months after acute COVID-19. Autoimmune profile and immunological statuses were evaluated mainly by enzyme-linked-immunosorbent assays and flow cytometry. RESULTS: Latent autoimmunity and overt autoimmunity persisted over time. A proinflammatory state was observed in patients with PCS characterized by up-regulated interferon-α, tumor necrosis factor-α, granulocyte colony-stimulating factor (G-CSF), interleukin (IL)-17A, IL-6, IL-1ß, and IL-13, whereas interferon-γ-induced protein 10 (IP-10) was decreased. In addition, PCS was characterized by increased levels of Th9, CD8+ effector T cells, naive B cells, and CD4+ effector memory T cells. Total levels of immunoglobulin G S1-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies remained elevated over time. CONCLUSIONS: The clinical manifestations of PCS are associated with the persistence of a proinflammatory and effector phenotype induced by SARS-CoV-2 infection. This long-term persistent immune activation may contribute to the development of latent and overt autoimmunity. Results suggest the need to evaluate the role of immunomodulation in the treatment of PCS.

Autoimmunity is a hallmark of post-COVID syndrome.

Autoimmunity has emerged as a characteristic of the post-COVID syndrome (PCS), which may be related to sex. In order to further investigate the relationship between SARS-CoV-2 and autoimmunity in PCS, a clinical and serological assessment on 100 patients was done. Serum antibody profiles against self-antigens and infectious agents were evaluated by an antigen array chip for 116 IgG and 104 IgM antibodies. Thirty pre-pandemic healthy individuals were included as a control group. The median age of patients was 49 years (IQR: 37.8 to 55.3). There were 47 males. The median post-COVID time was 219 (IQR: 143 to 258) days. Latent autoimmunity and polyautoimmunity were found in 83% and 62% of patients, respectively. Three patients developed an overt autoimmune disease. IgG antibodies against IL-2, CD8B, and thyroglobulin were found in more than 10% of the patients. Other IgG autoantibodies, such as anti-interferons, were positive in 5-10% of patients. Anti-SARS-CoV-2 IgG antibodies were found in > 85% of patients and were positively correlated with autoantibodies, age, and body mass index (BMI). Few autoantibodies were influenced by age and BMI. There was no effect of gender on the over- or under-expression of autoantibodies. IgG anti-IFN-λ antibodies were associated with the persistence of respiratory symptoms. In summary, autoimmunity is characteristic of PCS, and latent autoimmunity correlates with humoral response to SARS-CoV-2.

New insights into the taxonomy of autoimmune diseases based on polyautoimmunity.

OBJECTIVE: The clinical coexistence of two or more autoimmune diseases (ADs) fulfilling classification criteria is termed "overt polyautoimmunity" (PolyA), whereas the presence of autoantibodies unrelated to an index AD, without clinical criteria fulfillment, is known as "latent PolyA". We aimed to explore a new taxonomy of ADs based on PolyA. METHODS: In a cross-sectional study of 292 subjects, we evaluated the presence of PolyA in 146, 45, 29, 17, and 17 patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Sjögren's syndrome (SS), autoimmune thyroid disease (AITD) and systemic sclerosis (SSc), respectively, and 38 healthy controls. Clinical assessment, autoantibody profile (by autoantigen array chip), lymphocytes immunophenotype and cytokine profile (by flow cytometry) were evaluated simultaneously. A mixed cluster methodology was used to classify ADs. RESULTS: Latent PolyA was more frequent than overt PolyA, ranging from 69.9% in RA to 100% in SSc. Nevertheless, both latent and overt PolyA clustered together. Over-expressed IgG autoantibodies were found to be hallmarks for the identification of index ADs. The combination of autoantibodies allowed high accuracy in the classification of ADs. Three well-defined clusters based on PolyA were observed with distinctive clinical and immunological phenotypes. CONCLUSIONS: This proof-of-concept study indicates that ADs can be classified according to PolyA. PolyA should be considered in all studies dealing with ADs, including epidemiological, genetic, and clinical trials.

Safety and efficacy of convalescent plasma for severe COVID-19: a randomized, single blinded, parallel, controlled clinical study.

BACKGROUND: Convalescent plasma (CP) has been widely used to treat COVID-19 and is under study. However, the variability in the current clinical trials has averted its wide use in the current pandemic. We aimed to evaluate the safety and efficacy of CP in severe coronavirus disease 2019 (COVID-19) in the early stages of the disease. METHODS: A randomized controlled clinical study was conducted on 101 patients admitted to the hospital with confirmed severe COVID-19. Most participants had less than 14 days from symptoms onset and less than seven days from hospitalization. Fifty patients were assigned to receive CP plus standard therapy (ST), and 51 were assigned to receive ST alone. Participants in the CP arm received two doses of 250 mL each, transfused 24 h apart. All transfused plasma was obtained from "super donors" that fulfilled the following criteria: titers of anti-SARS-CoV-2 S1 IgG ≥ 1:3200 and IgA ≥ 1:800 antibodies. The effect of transfused anti-IFN antibodies and the SARS-CoV-2 variants at the entry of the study on the overall CP efficacy was evaluated. The primary outcomes were the reduction in viral load and the increase in IgG and IgA antibodies at 28 days of follow-up. The per-protocol analysis included 91 patients. RESULTS: An early but transient increase in IgG anti-S1-SARS-CoV-2 antibody levels at day 4 post-transfusion was observed (Estimated difference [ED], - 1.36; 95% CI, - 2.33 to - 0.39; P = 0.04). However, CP was not associated with viral load reduction in any of the points evaluated. Analysis of secondary outcomes revealed that those patients in the CP arm disclosed a shorter time to discharge (ED adjusted for mortality, 3.1 days; 95% CI, 0.20 to 5.94; P = 0.0361) or a reduction of 2 points on the WHO scale when compared with the ST group (HR adjusted for mortality, 1.6; 95% CI, 1.03 to 2.5; P = 0.0376). There were no benefits from CP on the rates of intensive care unit admission (HR, 0.82; 95% CI, 0.35 to 1.9; P = 0.6399), mechanical ventilation (HR, 0.66; 95% CI, 0.25 to 1.7; P = 0.4039), or mortality (HR, 3.2; 95% CI, 0.64 to 16; P = 0.1584). Anti-IFN antibodies and SARS-CoV-2 variants did not influence these results. CONCLUSION: CP was not associated with viral load reduction, despite the early increase in IgG anti-SARS-CoV-2 antibodies. However, CP is safe and could be a therapeutic option to reduce the hospital length of stay. Trial registration NCT04332835.

COVID-19 convalescent plasma composition and immunological effects in severe patients.

Convalescent plasma (CP) has emerged as a treatment for COVID-19. However, the composition and mechanism of action are not fully known. Therefore, we undertook a two-phase controlled study in which, first the immunological and metabolomic status of recovered and severe patients were evaluated. Secondly, the 28-day effect of CP on the immune response in severe patients was assessed. Nineteen recovered COVID-19 patients, 18 hospitalized patients with severe disease, and 16 pre-pandemic controls were included. Patients with severe disease were treated with CP transfusion and standard therapy (i.e., plasma recipients, n = 9) or standard therapy alone (n = 9). Clinical and biological assessments were done on day 0 and during follow-up on days 4, 7, 14, and 28. Clinical parameters, viral load, total immunoglobulin (Ig) G and IgA anti-S1-SARS-CoV-2 antibodies, neutralizing antibodies (NAbs), autoantibodies, cytokines, T and B cells, and metabolomic and lipidomic profiles were examined. Total IgG and IgA anti-S1-SARS-CoV-2 antibodies were key factors for CP selection and correlated with NAbs. In severe COVID-19 patients, mostly interleukin (IL)-6 (P = <0.0001), IL-10 (P = <0.0001), IP-10 (P = <0.0001), fatty acyls and glycerophospholipids were higher than in recovered patients. Latent autoimmunity and anti-IFN-α antibodies were observed in both recovered and severe patients. COVID-19 CP induced an early but transient cytokine profile modification and increases IgG anti-S1-SARS-CoV-2 antibodies. At day 28 post-transfusion, a decrease in activated, effector and effector memory CD4+ (P < 0.05) and activated and effector CD8+ (P < 0.01) T cells and naïve B cells (P = 0.001), and an increase in non-classical memory B cells (P=<0.0001) and central memory CD4+ T cells (P = 0.0252) were observed. Moreover, IL-6/IFN-γ (P = 0.0089) and IL-6/IL-10 (P = 0.0180) ratios decreased in plasma recipients compared to those who received standard therapy alone. These results may have therapeutic implications and justify further post-COVID-19 studies.

Ebola virus disease: An emerging and re-emerging viral threat.

The genus Ebolavirus from the family Filoviridae is composed of five species including Sudan ebolavirus, Reston ebolavirus, Bundibugyo ebolavirus, Taï Forest ebolavirus, and Ebola virus (previously known as Zaire ebolavirus). These viruses have a large non-segmented, negative-strand RNA of approximately 19 kb that encodes for glycoproteins (i.e., GP, sGP, ssGP), nucleoproteins, virion proteins (i.e., VP 24, 30,40) and an RNA dependent RNA polymerase. These viruses have become a global health concern because of mortality, their rapid dissemination, new outbreaks in West-Africa, and the emergence of a new condition known as "Post-Ebola virus disease syndrome" that resembles inflammatory and autoimmune conditions such as rheumatoid arthritis, systemic lupus erythematosus and spondyloarthritis with uveitis. However, there are many gaps in the understanding of the mechanisms that may induce the development of such autoimmune-like syndromes. Some of these mechanisms may include a high formation of neutrophil extracellular traps, an uncontrolled "cytokine storm", and the possible formation of auto-antibodies. The likely appearance of autoimmune phenomena in Ebola survivors suppose a new challenge in the management and control of this disease and opens a new field of research in a special subgroup of patients. Herein, the molecular biology, pathogenesis, clinical manifestations, and treatment of Ebola virus disease are reviewed and some strategies for control of disease are discussed.

Autoinflammatory and autoimmune conditions at the crossroad of COVID-19.

Coronavirus disease 2019 (COVID-19) has been categorized as evolving in overlapping phases. First, there is a viral phase that may well be asymptomatic or mild in the majority, perhaps 80% of patients. The pathophysiological mechanisms resulting in minimal disease in this initial phase are not well known. In the remaining 20% of cases, the disease may become severe and/or critical. In most patients of this latter group, there is a phase characterized by the hyperresponsiveness of the immune system. A third phase corresponds to a state of hypercoagulability. Finally, in the fourth stage organ injury and failure occur. Appearance of autoinflammatory/autoimmune phenomena in patients with COVID-19 calls attention for the development of new strategies for the management of life-threatening conditions in critically ill patients. Antiphospholipid syndrome, autoimmune cytopenia, Guillain-Barré syndrome and Kawasaki disease have each been reported in patients with COVID-19. Here we present a scoping review of the relevant immunological findings in COVID-19 as well as the current reports about autoinflammatory/autoimmune conditions associated with the disease. These observations have crucial therapeutic implications since immunomodulatory drugs are at present the most likely best candidates for COVID-19 therapy. Clinicians should be aware of these conditions in patients with COVID-19, and these observations should be considered in the current development of vaccines.

Chronic inflammatory demyelinating polyneuropathy as an autoimmune disease.

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune disease characterized by neurological symptoms and signs of progressive weakness, paresthesias, and sensory dysfunction. Other symptoms include reduced or absent tendon reflexes, cranial nerve involvement, autonomic symptoms, ataxia, and neuropathic pain. Unlike other autoimmune diseases, CIDP generally affects older individuals and has a male predominance. The onset is generally insidious and can take up to 8 weeks with a relapsing-recovery pattern. Like all autoimmune diseases, the etiology is multifactorial, with both genetic and environmental factors contributing to it. Case reports of CIDP have found associations with multiple pathogenic organisms including Hepatitis B and C viruses, Bartonella henselae, Mycoplasma pneumoniae, Human immunodeficiency virus, Cytomegalovirus and Epstein-Barr virus. Possible antigenic self-targets include myelin protein 0, myelin protein 2, peripheral myelin protein 22, Connexin 32, and myelin basic protein. Antibodies targeting the Ranvier node proteins such as contactin-1, contactin-associated protein 1, and neurofascin 155 have been described. CIDP is treated with rehabilitation and pharmacological modalities. Pharmacological treatments target autoimmune dysfunction and include corticosteroids, intravenous immunoglobulin, subcutaneous immunoglobulin, plasma exchange, immunosuppressive and immunomodulatory agents such as methotrexate, cyclophosphamide, rituximab, and mycophenolate mofetil. Although there are few observational studies and randomized clinical trials with limited evidence supporting the use of immunosuppressive drugs, they are widely used in clinical practice. A comprehensive review of CIDP is presented herein in light of the autoimmune tautology.

Cluster analysis of autoimmune rheumatic diseases based on autoantibodies. New insights for polyautoimmunity.

Autoimmune diseases (ADs) are a chronic and clinically heterogeneous group of diseases characterized by share common immunopathogenic mechanisms and risk factors (i.e., the autoimmune tautology), which explain the fact that one AD may coexist with others (i.e., polyautoimmunity - PolyA). In the present exploratory study, a mixed-cluster analysis of the most common autoimmune rheumatic diseases (ARDs) was done. A total of 187 consecutive women with established systemic lupus erythematosus (n = 70), rheumatoid arthritis (n = 51), systemic sclerosis (n = 35) and Sjögren's syndrome (n = 31) were included. A comprehensive clinical, autoantibody and cytokine assessment was simultaneously done. Total PolyA was registered in 142 (75.9%) patients. Six clusters were obtained, built mainly on autoantibodies: PolyA-I to -VI. The PolyA-III cluster showed the highest frequency of overt PolyA (p = 0.01), and the PolyA-I, -III, and -IV clusters exhibited the highest positivity for IL-12/23p40 (p = 0.015). These results provide new insights into the pathophysiology of PolyA and warrant prospective validation to enable development of a more accurate taxonomy of ARDs.

Cytokine imbalance in patients with systemic sclerosis and resilience: the key role of interleukin-6.

OBJECTIVES: Resilience, the ability to respond positively to adverse events, may be influenced by long-term stressors and autoimmune/inflammatory conditions such as systemic sclerosis (SSc). Since the immune system plays a role in the development of resilience, we aimed to evaluate the relationship between a panel of cytokines and resilience in patients with SSc. METHODS: Thirty-five consecutive women with established SSc were involved in this exploratory study. Clinical characteristics, including severity of symptoms and resilience, a panel of 15 serum cytokines and 17 autoantibodies were assessed simultaneously. Multivariate methods were used to analyse the data. RESULTS: Interleukin-6 (IL-6) levels were associated with severity of symptoms (ß=1.8395, p=0.04), and low resilience scores (ß= -0.581120, p=0.02). Furthermore, resilience was not associated with clinical manifestations nor polyautoimmunity. Cytokine levels did not significantly differ between groups based on regular physical activity. CONCLUSIONS: The results highlight the importance of IL-6 as a key mediator in the altered cytokine network of SSc.

The autoimmune ecology: an update.

PURPOSE OF REVIEW: The autoimmune ecology refers to the interactions between individuals and their environment leading to a breakdown in immune tolerance and, therefore, to the development of one or more autoimmune diseases in such an individual. Herein, an update is offered on four specific factors associated with autoimmune diseases, namely, vitamin D, smoking, alcohol and coffee consumption from the perspective of exposome and metabolomics. RECENT FINDINGS: Smoking is associated with an increased risk for most of the autoimmune diseases. Carbamylation of proteins as well as NETosis have emerged as possible new pathophysiological mechanisms for rheumatoid arthritis. Low-to-moderate alcohol consumption seems to decrease the risk of systemic lupus erythematosus and rheumatoid arthritis, and studies of vitamin have suggested a beneficial effect on these conditions. Coffee intake appears to be a risk factor for type 1 diabetes mellitus and rheumatoid arthritis and a protective factor for multiple sclerosis and primary biliary cholangitis. SUMMARY: Recent studies support the previously established positive associations between environmental factors and most of the autoimmune diseases. Nevertheless, further studies from the perspective of metabolomics, proteomics and genomics will help to clarify the effect of environment on autoimmune diseases.

Molecular mimicry and autoimmunity.

Molecular mimicry is one of the leading mechanisms by which infectious or chemical agents may induce autoimmunity. It occurs when similarities between foreign and self-peptides favor an activation of autoreactive T or B cells by a foreign-derived antigen in a susceptible individual. However, molecular mimicry is unlikely to be the only underlying mechanism for autoimmune responses; other factors such as breach in central tolerance, non-specific bystander activation, or persistent antigenic stimuli (amongst others) may also contribute to the development of autoimmune diseases. Host genetics, exposure to microbiota and environmental chemicals are additional links to our understanding of molecular mimicry. Our current knowledge of the detailed mechanisms of molecular mimicry is limited by the issues of prolonged periods of latency before the appearance of disease, the lack of enough statistical power in epidemiological studies, the limitations of the potential role of genetics in human studies, the relevance of inbred murine models to the diverse human population and especially the limited technology to systematically dissect the human T-cell repertoire and B-cell responses. Nevertheless, studies on the role of autoreactive T-cells that are generated secondary to molecular mimicry, the diversity of the T-cell receptor repertoires of auto-reactive T-cells, the role of exposure to cryptic antigens, the generation of autoimmune B-cell responses, the interaction of microbiota and chemical adjuvants with the host immune systems all provide clues in advancing our understanding of the molecular mechanisms involved in the evolving concept of molecular mimicry and also may potentially aid in the prevention and treatment of autoimmune diseases.

Autonomic symptoms following Zika virus infection.

PURPOSE: To determine if autonomic symptoms are associated with previous Zika virus infection. METHODS: Case-control study including 35 patients with Zika virus infection without evidence of neurological disease and 105 controls. Symptoms of autonomic dysfunction were assessed with the composite autonomic symptom scale 31 (COMPASS-31). RESULTS: Patients with previous Zika virus infection had significantly higher COMPASS-31 score than controls regardless of age and sex (p = 0.007). The main drivers for the higher scores where orthostatic intolerance (p = 0.003), secretomotor (p = 0.04) and bladder symptoms (p < 0.001). CONCLUSION: Zika virus infection is associated with autonomic dysfunction. The mechanisms remain to be elucidated.

Cytokine and autoantibody clusters interaction in systemic lupus erythematosus.

BACKGROUND: Evidence supports the existence of different subphenotypes in systemic lupus erythematosus (SLE) and the pivotal role of cytokines and autoantibodies, which interact in a highly complex network. Thus, understanding how these complex nonlinear processes are connected and observed in real-life settings is a major challenge. Cluster approaches may assist in the identification of these subphenotypes, which represent such a phenomenon, and may contribute to the development of personalized medicine. Therefore, the relationship between autoantibody and cytokine clusters in SLE was analyzed. METHODS: This was an exploratory study in which 67 consecutive women with established SLE were assessed. Clinical characteristics including disease activity, a 14-autoantibody profile, and a panel of 15 serum cytokines were measured simultaneously. Mixed-cluster methodology and bivariate analyses were used to define autoantibody and cytokine clusters and to identify associations between them and related variables. RESULTS: First, three clusters of autoantibodies were defined: (1) neutral, (2) antiphospholipid antibodies (APLA)-dominant, and (3) anti-dsDNA/ENA-dominant. Second, eight cytokines showed levels above the threshold thus making possible to find 4 clusters: (1) neutral, (2) chemotactic, (3) G-CSF dominant, and (4) IFNα/Pro-inflammatory. Furthermore, the disease activity was associated with cytokine clusters, which, in turn, were associated with autoantibody clusters. Finally, when all biomarkers were included, three clusters were found: (1) neutral, (2) chemotactic/APLA, and (3) IFN/dsDNA, which were also associated with disease activity. CONCLUSION: These results support the existence of three SLE cytokine-autoantibody driven subphenotypes. They encourage the practice of personalized medicine, and support proof-of-concept studies.

A comprehensive analysis and immunobiology of autoimmune neurological syndromes during the Zika virus outbreak in Cúcuta, Colombia.

We have focused on the epidemiology and immunobiology of Zika virus (ZIKV) infection and factors associated with the development of Guillain-Barré syndrome (GBS) and other neurological syndromes in Cúcuta, the capital of North Santander department, Colombia. Data of patients with ZIKV disease reported to the national population-based surveillance system were used to calculate the basic reproduction number (R0) and the attack rates (ARs) as well as to develop epidemiological maps. Patients with neurological syndromes were contacted and their diagnoses were confirmed. A case-control study in which 29 patients with GBS associated with ZIKV compared with 74-matched control patients with ZIKV infection alone was undertaken. Antibodies against arboviruses and other infections that may trigger GBS were evaluated. The estimated value of R0 ranged between 2.68 (95% CI 2.54-2.67) to 4.57 (95% CI 4.18-5.01). The sex-specific ARs were 1306 per 100,000 females, and 552 per 100,000 males. A non-linear interaction between age and gender on the ARs was observed. The incidence of GBS in Cúcuta increased 4.41 times secondary to ZIKV infection. The lag time between ZIKV infection and neurological symptoms was 7 days (interquartile range 2-14.5). Patients with GBS appeared to represent a lower socioeconomic status and were living near to environmentally contaminated areas. All GBS patients were positive for IgG antibodies against both ZIKV and Dengue virus, and 69% were positive for Chikungunya virus. Noteworthy, GBS was associated with a previous infection with M. pneumoniae (OR: 3.95; 95% CI 1.44-13.01; p = 0.006). No differences in antibody levels against C. jejuni, Epstein-Barr virus and cytomegalovirus were observed. High rates of cranial nerves involvement and dysautonomia were present in 82% and 75.9%, respectively. Intensive care unit (ICU) admission was necessary in 69% of the GBS patients. Most of the patients disclosed a high disability condition (Hughes grade 4). Dysautonomia was the main risk factor of poor GBS prognosis (i.e., ICU admission and disability). Thirteen patients were diagnosed with other neurological syndromes different to GBS (6 with transverse myelitis, 3 with encephalitis, 3 with peripheral facial palsy and one with thoraco-lumbosacral myelopathy). Our data confirm an increased transmission of ZIKV in Cúcuta, and provide support to the view that severe neurological syndromes are related to ZIKV disease. The complex ways by which previous infections and socioeconomic status interact to increase the risk of GBS in people infected by ZIKV should be further investigated.

Zika virus and neurologic autoimmunity: the putative role of gangliosides.

An increasing number of severe neurological complications associated with Zika virus (ZIKV), chiefly Guillain-Barré syndrome (GBS) and primary microcephaly, have led the World Health Organization to declare a global health emergency. Molecular mimicry between glycolipids and surface molecules of infectious agents explain most of the cases of GBS preceded by infection, while a direct toxicity of ZIKV on neural cells has been raised as the main mechanism by which ZIKV induces microcephaly. Gangliosides are crucial in brain development, and their expression correlates with neurogenesis, synaptogenesis, synaptic transmission, and cell proliferation. Targeting the autoimmune response to gangliosides may represent an underexploited opportunity to examine the increased incidence of neurological complications related to ZIKV infection.