Anti-neurofascin-155 antibody mediated a distinct phenotype of chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

To investigate Ranvier's autoantibodies prevalence and isotypes in various peripheral neuropathy variants, compare clinical features between seronegative and seropositive patients, and elucidate immune mechanisms underlying antibody generation.

METHODS

Antibodies against anti-neurofascin-155 (NF155), NF186, contactin-1 (CNTN1), CNTN2, contactin-associated protein 1 (CASPR1), and CASPR2 were identified through cell-based assays. Plasma cytokines were analyzed in anti-NF155 antibody-positive chronic inflammatory demyelinating polyneuropathy (NF155+ CIDP) and Ranvier's antibodies-negative CIDP (Ab- CIDP) patients using a multiplexed fluorescent immunoassay, validated in vitro in a cell culture model.

RESULTS

In 368 plasma samples, 50 Ranvier's autoantibodies were found in 45 individuals, primarily in CIDP cases (25 out of 69 patients) and in 10 out of 122 Guillain-Barré syndrome patients. Anti-NF155 and CNTN1-IgG were exclusive to CIDP. Fourteen samples were NF155-IgG, primarily IgG4 subclass, linked to CIDP features including early onset, tremor, sensory disturbance, elevated CSF protein, prolonged motor latency, conduction block, and poor treatment response. NF155-IgG had low sensitivity (20.28%) but high specificity (100%) for CIDP, rising to 88.88% with tremor and prolonged motor latency. Cytokine profiling in NF155+ CIDP revealed distinct immune responses involving helper T cells, toll-like receptor pathways. Some NF155+ CIDP patients had circulating NF155-specific B cells producing NF155-IgG without antigen presence, suggesting therapeutic potential.

CONCLUSION

The study emphasizes the high specificity and sensitivity of NF155-IgG for diagnosing CIDP characterized by distinctive features. Further investigation into circulating NF155-specific B cell phenotypes may pave the way for B cell directed therapy.

T cell responses in immune-mediated IgA nephropathy

Immunoglobulin A nephropathy (IgAN) is a complex autoimmune disease with various underlying causes and significant clinical heterogeneity. There are large individual differences in its development, and the etiology and pathogenesis are still poorly understood. While it is known that immunobiological factors play a significant role in the pathophysiology of IgAN, the specific nature of these factors has yet to be fully elucidated. Numerous investigations have verified that cluster of differentiation 4+ (CD4+) and CD8+ T lymphocytes are involved in the immunopathogenesis of IgAN. Furthermore, certain data also point to γδT cells' involvement in the pathophysiology of IgAN. By thoroughly examining the mechanisms of action of these T cells in the context of IgAN, this review sheds light on the immunopathogenesis of the disease and its associated factors. The review is intended to provide reference value for the future research in this field and promising treatment clues for clinical patients.

The Role of Immune Mechanisms in Abdominal Aortic Aneurysm: Could It be a Promising Therapeutic Strategy?

Abdominal aortic aneurysm (AAA) is an enlargement of the aorta greater than 50% in diameter. Although up to 80% of cases result in mortality if the aneurysm ruptures, patients are often diagnosed too late, as most cases are asymptomatic. The current treatment for AAA is still surgery as there are currently no effective drug treatments. Knowledge of the pathophysiological mechanisms is essential for the development of new preventive and therapeutic approaches. However, the molecular mechanisms are complex and remain unclear. Apoptosis of vascular smooth muscle cells, the major cellular component of the aorta, and degeneration of the extracellular matrix, the skeleton of the aortic wall, are hallmarks of AAA pathology. Inflammation, mainly through macrophage cells, has been recognized as a central factor in the development of AAA. Macrophage cells also orchestrate other pathways and immune cells involved in this process. Macrophages do not exist as pure populations at aneurysm sites. M1 macrophages are pro-inflammatory and weaken the aortic wall during AAA development. M2 macrophages, in contrast, are involved in anti-inflammatory reactions and aorta tissue repair. The balancing effect on AAA progression makes M1/M2 macrophages therapeutic targets to control inflammation and destruction of the aortic wall. An early diagnosis is also important to allow for early interventions. This review article, based on the available data, aims to evaluate the role of an immunotherapeutic approach in controlling AAA development by briefly discussing the immunological mechanisms.

Fungal infections: Immune defense, immunotherapies and vaccines

Invasive fungal infection is an under recognized and emerging global health threat. Recently, the World Health Organization (WHO) released the first ever list of health-threatening fungi to guide research and public health interventions to strengthen global response to fungi infections and antifungal resistance. Currently, antifungal drugs only demonstrate partial success in improving prognosis of infected patients, and this is compounded by the rapid evolution of drug resistance among fungi species. The increased prevalence of fungal infections in individuals with underlying immunological deficiencies reflects the importance of an intact host immune system in controlling mycoses, and further highlights immunomodulation as a potential new avenue for the treatment of disseminated fungal diseases. In this review, we will summarize how host innate immune cells sense invading fungi through their pattern recognition receptors, and subsequently initiate a series of effector mechanisms and adaptive immune responses to mediate fungal clearance. In addition, we will discuss emerging preclinical and clinical data on antifungal immunotherapies and fungal vaccines which can potentially expand our antifungal armamentarium in future.

Sleep disturbance is associated with perturbations in immune-inflammatory pathways in oncology outpatients undergoing chemotherapy

OBJECTIVE/BACKGROUND

Sleep disturbance is a common problem in patients receiving chemotherapy. Purpose was to evaluate for perturbations in immune-inflammatory pathways between oncology patients with low versus very high levels of sleep disturbance.

PATIENTS/METHODS

Sleep disturbance was evaluated using the General Sleep Disturbance Scale six times over two cycles of chemotherapy. Latent profile analysis was used to identify subgroups of patients with distinct sleep disturbance profiles. Pathway impact analyses were performed in two independent samples using gene expression data obtained from RNA sequencing (n = 198) and microarray (n = 162) technologies. Fisher's combined probability test was used to identify significantly perturbed pathways between Low versus Very High sleep disturbance classes.

RESULTS

In the RNA sequencing and microarray samples, 59.1% and 51.9% of patients were in the Very High sleep disturbance class, respectively. Thirteen perturbed pathways were related to immune-inflammatory mechanisms (i.e., endocytosis, phagosome, antigen processing and presentation, natural killer cell mediated cytotoxicity, cytokine-cytokine receptor interaction, apoptosis, neutrophil extracellular trap formation, nucleotide-binding and oligomerization domain-like receptor signaling, Th17 cell differentiation, intestinal immune network for immunoglobulin A production, T-cell receptor signaling, complement and coagulation cascades, and tumor necrosis factor signaling).

CONCLUSIONS

First study to identify perturbations in immune-inflammatory pathways associated with very high levels of sleep disturbance in oncology outpatients. Findings suggest that complex immune-inflammatory interactions underlie sleep disturbance.

Immune Mechanisms and Related Targets for the Treatment of Fibrosis in Various Organs

Inflammation and fibrosis are two inter-related disease pathologies with several overlapping components. Three specific cell types, macrophages, T helper cells and myofibroblasts, each play important roles in regulating both processes. Following tissue injury, an inflammatory stimulus is often necessary to initiate tissue repair, where cytokines released from infiltrating and resident immune and inflammatory cells stimulate the proliferation and activation of extracellular matrix-producing myofibroblasts. However, persistent tissue injury drives an inappropriate pro-fibrotic response. Additionally, activated myofibroblasts can take on the role of traditional antigen-presenting cells, secrete pro-inflammatory cytokines, and recruit inflammatory cells to fibrotic foci, amplifying the fibrotic response in a vicious cycle. Moreover, inflammatory cells have been shown to play contradictory roles in the initiation, amplification and resolution of fibrotic disease processes. The central role of the inflammasome molecular platform in contributing to fibrosis is only beginning to be fully appreciated. In this review, we discuss the immune mechanisms that can lead to fibrosis, the inflammasomes that have been implicated in the fibrotic process in the context of the immune response to injury, and also discuss current and emerging therapies that target inflammasome-induced collagen deposition to treat organ fibrosis.

Gene expression in the epileptic (EL) mouse hippocampus

The neuropathology of hippocampal seizure foci in human temporal lobe epilepsy (TLE) and several animal models of epilepsy reveal extensive neuronal loss along with astrocyte and microglial activation. Studies of these models have advanced hypotheses that propose both pathological changes are essential for seizure generation. However, some seizure foci in human TLE show an extreme loss of neurons in all hippocampal fields, giving weight to hypotheses that favor neuroglia as major players. The epileptic (EL) mouse is a seizure model in which there is no observable neuron loss but associated proliferation of microglia and astrocytes and provides a good model to study the role of activated neuroglia in the presence of an apparently normal population of neurons. While many studies have been carried out on the EL mouse, there is a paucity of studies on the molecular changes in the EL mouse hippocampus, which may provide insight on the role of neuroglia in epileptogenesis. In this paper we have applied high throughput gene expression analysis to identify the molecular changes in the hippocampus that may explain the pathological processes. We have observed several classes of genes whose expression levels are changed. It is hypothesized that the upregulation of heat shock proteins (HSP70, HSP72, FOSL2 (HSP40), and their molecular chaperones BAG3 and DNAJB5 along with the down regulated gene MALAT1 may contribute to the neuroprotection observed. The increased expression of BDNF along with immediate early gene expression (FosB, JunB, ERG4, NR4A1, NR4A2, FBXO3) and the down regulation of GABRD, DBP and MALAT1 it is hypothesized may contribute to the hyperexcitability of the hippocampal neurons in this model. Activated astrocytes and microglia may also contribute to excitability pathomechanisms. Activated astrocytes in the ELS mouse are deficient in glutamine synthetase and thus reduce the clearance of extracellular glutamate. Activated microglia which may be associated with C1Q and MHC class I molecules we propose may mediate a process of selective removal of defective GABAergic synapses through a process akin to trogocytosis that may reduce neuronal inhibition and favor hyperexcitability.

Physiopathology of food allergies

Food allergy is adverse reaction to certain foods and it arise from a specific immune response, including reactions mediated by immunoglobulin (Ig) E, by cells, or by both. Although individuals of all ages can develop it, the pediatric population is the most affected by it; with a prevalence of 6 to 8 %. In homeostatic conditions, the organism has tolerance and regulation pathways that hinder food components from causing damage or adverse immune reactions. However, under specific conditions such as genetic predisposition, environmental factors, dietary patterns, or premature exposure to certain foods, tolerance is not developed and aberrant and excessive immune responses to food antigens happen. Understanding the complex physiopathological mechanisms that are present during the establishment and evolution of food allergies allows the identification of potential therapeutic targets and the development of more effective therapies aimed to modify the natural course of the allergy and to improve the patients' quality of life. The objective of this review is to give an updated vision of the existing knowledge about predisposition, sensitization pathways, manifestations, and therapies in IgE-mediated food allergies, delving into the molecular and cellular mechanisms of its physiopathology.

Circulating tumor cells in cancer patients: developments and clinical applications for immunotherapy

Cancer metastasis is the leading cause of cancer-related death. Circulating tumor cells (CTCs) are shed into the bloodstream from either primary or metastatic tumors during an intermediate stage of metastasis. In recent years, immunotherapy has also become an important focus of cancer research. Thus, to study the relationship between CTCs and immunotherapy is extremely necessary and valuable to improve the treatment of cancer. In this review, based on the advancements of CTC isolation technologies, we mainly discuss the clinical applications of CTCs in cancer immunotherapy and the related immune mechanisms of CTC formation. In order to fully understand CTC formation, sufficiently and completely understood molecular mechanism based on the different immune cells is critical. This understanding is a promising avenue for the development of effective immunotherapeutic strategies targeting CTCs.

Quantification of Nitric Oxide and Reactive Oxygen Species in Leishmania-infected J774A.1 Macrophages as a Response to the in vitro treatment with a Natural Product Compound

Leishmaniasis is a parasitic disease caused by the obligatory intracellular protozoa Leishmania spp. Current therapeutic options are limited and thus, drug discovery against leishmaniasis is very important. Nevertheless, there is a great difficulty to develop therapeutic strategies against the disease because the parasite deploys various mechanisms to evade the immune system and multiply inside the host. Among the main factors of the immunity that are recruited to confront the Leishmania infection are the macrophages (MΦs) that produce effector molecules such as Nitric Oxide (NO) and Reactive Oxygen Species (ROS). Therefore, efficient drug agents should combine the antileishmanial effect of these gaseous transmitters along with the enhancement of the host's adaptive immunity. In the quest of therapeutic alternatives, natural products have been extensively studied and are considered as candidate antileishmanial agents since they exhibit specific properties in modulating the host's immune response towards an effective anti-leishmanial cell-mediated immunity capable to eliminate parasitic dissemination. In the current protocol, Leishmania-infected MΦs (J774A.1 cell line) that have been treated with various increasing concentrations of a natural compound, are tested for the production of the aforementioned molecules. In order to detect NO production, we employ the Griess colorimetric nitrite assay and quantification relies on the construction of an accurate standard curve using appropriate standards of known concentration. ROS detection and quantification is achieved by flow cytometry and relies on the use of carboxy-H₂DCFDA, an indicator that converts to a fluorescent form when interacts with ROS molecules.

Advax augments B and T cell responses upon influenza vaccination via the respiratory tract and enables complete protection of mice against lethal influenza virus challenge

Administration of influenza vaccines via the respiratory tract has potential benefits over conventional parenteral administration, inducing immunity directly at the site of influenza exposure as well as being needle free. In this study, we investigated the suitability of Advax™, a stable particulate polymorph of inulin, also referred to as delta inulin, as a mucosal adjuvant for whole inactivated influenza vaccine (WIV) administered either as a liquid or dry powder formulation. Spray freeze-drying produced Advax-adjuvanted WIV powder particles in a size range (1-5 μm) suitable for inhalation. The physical and biological characteristics of both WIV and Advax remained unaltered both by admixing WIV with Advax and by spray freeze drying. Upon intranasal or pulmonary immunization, both liquid and dry powder formulations containing Advax induced significantly higher systemic, mucosal and cellular immune responses than non-adjuvanted WIV formulations. Furthermore, pulmonary immunization with Advax-adjuvanted WIV led to robust memory B cell responses along with an increase of lung localization factors i.e. CXCR3, CD69, and CD103. A less pronounced but still positive effect of Advax was seen on memory T cell responses. In contrast to animals immunized with WIV alone, all animals pulmonary immunized with a single dose of Advax-adjuvanted WIV were fully protected with no visible clinical symptoms against a lethal dose of influenza virus. These data confirm that Advax is a potent mucosal adjuvant that boosts vaccine-induced humoral and cellular immune responses both in the lung and systemically with major positive effects on B-cell memory and complete protection against live virus. Hence, respiratory tract immunization, particularly via the lungs, with Advax-adjuvanted WIV formulation as a liquid or dry powder is a promising alternative to parenteral influenza vaccination.

Inflammatory cells implicated in neoplasia development in idiopathic inflammatory bowel disease

The inflammatory mechanisms that lead to the clinical symptoms that are grouped under the term inflammatory bowel disease have not been fully characterized. Although a specific mechanism has not been identified, inflammatory bowel disease is believed to be related to an inability by the immune system to shut active inflammation within the intestine. Many contributing factors have been implicated in the disease process. Based on population studies, patients with inflammatory bowel disease have an increased risk for neoplastic development. Although no specific immune cell has been implicated in neoplastic development within this patient population, several immune cells have been implicated as possible etiologies in inflammatory bowel disease. In this review, we will review the clinical evidence about the risk for neoplastic development in inflammatory bowel disease and the current clinical guidelines to survey this patient population. We will also review the pathologic assessment of inflammation within this patient population as well the underlying immune cells and cytokines that have been implicated in the etiology of inflammatory bowel disease.

Transcriptome analysis of hepatopancraes of Procambarus clarkii challenged with polyriboinosinic polyribocytidylic acid (poly I:C)

Crustacean hepatopancreas regulates metabolic processes, biogenesis and innate immune processes, and the knowledge on its immune genes are crucial to understand antimicrobial mechanisms. In this study, we reported the transcriptomic profile of Procambarus clarkii hepatopancreas after poly I:C administration using high-throughput sequencing. Following de novo assembly 56,716 unigene sequences with an average length of 810 bp was obtained. The unigene sequences were annotated to three ontologies including cellular components, biological processes and molecular functions, further 56,716 unigene sequences were mapped to 25 COG categories. A total of 2497 differentially expressed genes (DEGs) were identified following the comparative analysis between poly I:C treated and control group, and then KEGG enrichment analysis were performed to detect immune related pathways. Quantitative real time polymerase chain reaction showed that the selected DEGs significantly up-regulated following poly I:C administration in comparison to control group. The transcriptomic sequence information will improve the knowledge of this economically important crustacean, and will shed light on its antiviral immune mechanisms.

The Biology of Chronic Graft-versus-Host Disease: A Task Force Report from the National Institutes of Health Consensus Development Project on Criteria for Clinical Trials in Chronic Graft-versus-Host Disease

Chronic graft-versus-host disease (GVHD) is the leading cause of late, nonrelapse mortality and disability in allogeneic hematopoietic cell transplantation recipients and a major obstacle to improving outcomes. The biology of chronic GVHD remains enigmatic, but understanding the underpinnings of the immunologic mechanisms responsible for the initiation and progression of disease is fundamental to developing effective prevention and treatment strategies. The goals of this task force review are as follows: This document is intended as a review of our understanding of chronic GVHD biology and therapies resulting from preclinical studies, and as a platform for developing innovative clinical strategies to prevent and treat chronic GVHD.

Immunotherapy of Sepsis: Blind Alley or Call for Personalized Assessment?

Sepsis is the most frequent cause of death in noncoronary intensive care units. In the past 10 years, progress has been made in the early identification of septic patients and their treatment. These improvements in support and therapy mean that mortality is gradually decreasing, however, the rate of death from sepsis remains unacceptably high. Immunotherapy is not currently part of the routine treatment of sepsis. Despite experimental successes, the administration of agents to block the effect of sepsis mediators failed to show evidence for improved outcome in a multitude of clinical trials. The following survey summarizes the current knowledge and results of clinical trials on the immunotherapy of sepsis and describes the limitations of our knowledge of the pathogenesis of sepsis. Administration of immunomodulatory drugs should be linked to the current immune status assessed by both clinical and molecular patterns. Thus, a careful daily review of the patient's immune status needs to be introduced into routine clinical practice giving the opportunity for effective and tailored use of immunomodulatory therapy.

The puzzle of immune phenotypes of childhood asthma

Asthma represents the most common chronic childhood disease worldwide. Whereas preschool children present with wheezing triggered by different factors (multitrigger and viral wheeze), clinical asthma manifestation in school children has previously been classified as allergic and non-allergic asthma. For both, the underlying immunological mechanisms are not yet understood in depth in children. Treatment is still prescribed regardless of underlying mechanisms, and children are not always treated successfully. This review summarizes recent key findings on the complex mechanisms of the development and manifestation of childhood asthma. Whereas traditional classification of childhood asthma is primarily based on clinical symptoms like wheezing and atopy, novel approaches to specify asthma phenotypes are under way and face challenges such as including the stability of phenotypes over time and transition into adulthood. Epidemiological studies enclose more information on the patient’s disease history and environmental influences. Latest studies define endotypes based on molecular and cellular mechanisms, for example defining risk and protective single nucleotide polymorphisms (SNPs) and new immune phenotypes, showing promising results. Also, regulatory T cells and recently discovered T helper cell subtypes such as Th9 and Th17 cells were shown to be important for the development of asthma. Innate lymphoid cells (ILC) could play a critical role in asthma patients as they produce different cytokines associated with asthma. Epigenetic findings showed different acetylation and methylation patterns for children with allergic and non-allergic asthma. On a posttranscriptional level, miRNAs are regulating factors identified to differ between asthma patients and healthy controls and also indicate differences within asthma phenotypes. Metabolomics is another exciting chapter important for endotyping asthmatic children. Despite the development of new biomarkers and the discovery of new immunological molecules, the complex puzzle of childhood asthma is still far from being completed. Addressing the current challenges of distinct clinical asthma and wheeze phenotypes, including their stability and underlying endotypes, involves addressing the interplay of innate and adaptive immune regulatory mechanisms in large, interdisciplinary cohorts.

Vogt-Koyanagi-Harada disease: Novel insights into pathophysiology, diagnosis and treatment

Vogt-Koyanagi-Harada (VKH) disease is one of the major vision-threatening diseases in certain populations, such as Asians, native Americans, Hispanics and Middle Easterners. It is characterized by bilateral uveitis that is frequently associated with neurological (meningeal), auditory, and integumentary manifestations. Although the etiology and pathogenesis of VKH disease need to be further elucidated, it is widely accepted that the clinical manifestations are caused by an autoimmune response directed against melanin associated antigens in the target organs, i.e. the eye, inner ear, meninges and skin. In the past decades, accumulating evidence has shown that genetic factors, including VKH disease specific risk factors (HLA-DR4) and general risk factors for immune mediated diseases (IL-23R), dysfunction of immune responses, including the innate and adaptive immune system and environmental triggering factors are all involved in the development of VKH disease. Clinically, the criteria of diagnosis for VKH disease have been further improved by the employment of novel imaging techniques for the eye. For the treatment, early and adequate corticosteroids are still the mainstream regime for the disease. However, immunosuppressive and biological agents have shown benefit for the treatment of VKH disease, especially for those patients not responding to corticosteroids. This review is focused on our current knowledge of VKH disease, especially for the diagnosis, pathogenesis (genetic factors and immune mechanisms), ancillary tests and treatment. A better understanding of the role of microbiome composition, genetic basis and ongoing immune processes along with the development of novel biomarkers and objective quantitative assays to monitor intraocular inflammation are needed to improve current management of VKH patients.

Cutaneous immune mechanisms in canine leishmaniosis due to Leishmania infantum

Canine leishmaniosis (CanL) caused by the parasite Leishmania infantum is a systemic disease with variable clinical signs. The disease is endemic in the Mediterranean countries and dogs are the main domestic reservoir of the parasite. The quite complicated immune response against the parasite is crucial for the evolution of CanL infection with the skin playing a major role in its immunopathogenesis. After the inoculation of Leishmania promastigotes into the dermis by sand fly bites, complement factors, Langerhan's cells, neutrophils, fibroblasts and keratinocytes are involved in the activation of the innate arm of the skin immune system, with the macrophages and dendritic cells to play a major key role. The effective activation of cellular immunity is the cornerstone of dog's resistance against the parasite. Promastigotes reaching the dermis are engulfed, processed and transferred by APCs to draining lymph nodes to stimulate naïve T-cells for proliferation and differentiation into armed effector T-cells. Th1 cells activate the infected macrophages to kill Leishmania, whereas Th2 cells divert the immune response to humoral immunity and down regulation of cellular immunity with Th1 cell anergy. Inhibition of co-stimulatory molecules expression by infected macrophages contributes to T-cell anergy. In canine subclinical infections cutaneous lymphocytic infiltrate and parasites are absent, as opposed to dogs with clinical leishmaniosis. CD8+ cells constitute a significant population of cellular immunity in CanL since they outnumber CD4+ cells in the dermis, producing IFN-γ in sub clinically infected dogs and high levels of IL-4 in dogs with clinical leishmaniosis. Numerous B-lymphocytes have been shown to heavily infiltrate the dermis at least in exfoliative dermatitis in CanL. A mixed Th1/Th2 cytokine profile has been found in the dermis of naturally infected with L. infantum dogs. In the skin of dogs with clinical leishmaniosis, where plasma cells outnumber T lymphocytes in the dermal infiltrate, there is an overproduction of IL-4, IL-13 and TNF-α leading to Th2-biased humoral immune response. The issue of humoral immunity polarization in CanL remains controversial. Much still needs to be learned about other mechanisms underlying the complex interaction between the skin immune system and the parasite.

Fulminant myocarditis

Myocarditis is most often caused by a viral infection. Less common causes include other infectious agents and autoimmune diseases. Fulminant myocarditis is an unusual complication with a rapidly progressive course resulting in severe heart failure and cardiogenic shock. Fulminant myocarditis should be treated with full supportive care, using aggressive pharmacologic therapy and mechanical circulatory support, because significant improvement in left ventricular function will often occur. Cardiac transplantation is required in a small minority of patients. Cardiac magnetic resonance imaging is becoming a frequently used modality to aid in the diagnosis of myocarditis.