Immune conversations at the border: meningeal immunity in health and disease.

The brain and spinal cord, collectively known as the central nervous system, are encapsulated by an overlapping series of membranes known as the meninges. Once considered primarily a physical barrier for central nervous system protection, the bordering meninges are now recognized as highly immunologically active. The meninges host diverse resident immune cells and serve as a critical interface with peripheral immunity, playing multifaceted roles in maintaining central nervous system homeostasis, responding to pathogenic threats, and neurological disorders.

Gut Microbiome in Alzheimer's Disease: from Mice to Humans.

Alzheimer's disease (AD) is the most prevalent type of dementia, but its etiopathogenesis is not yet fully understood. Recent preclinical studies and clinical evidence indicate that changes in the gut microbiome could potentially play a role in the accumulation of amyloid beta. However, the relationship between gut dysbiosis and AD is still elusive.

Isolation of from the Oral Cavity of Immunocompetent Young Adults from the North of Mexico.

Unlabelled: The human oral cavity is normally colonized by microorganisms including bacteria, fungi, archaea, viruses and protozoa. The aim of this study was to determine the frequency of spp., in de oral cavity in a group of medical students from the north of Mexico.

Myelin-reactive B cells exacerbate CD4 T cell-driven CNS autoimmunity in an IL-23-dependent manner.

B cells and T cells collaborate in multiple sclerosis (MS) pathogenesis. IgH mice possess a B cell repertoire skewed to recognize myelin oligodendrocyte glycoprotein (MOG). Here, we show that upon immunization with the T cell-obligate autoantigen, MOG, IgH mice develop rapid and exacerbated experimental autoimmune encephalomyelitis (EAE) relative to wildtype (WT) counterparts, characterized by aggregation of T and B cells in the IgH meninges and by CD4 T helper 17 (Th17) cells in the CNS.

Identification of Intestinal Lamina Propria Plasma Cells by Surface Transmembrane Activator and CAML Interactor Expression.

Plasma cells secrete an abundance of Abs and are a crucial component of our immune system. The intestinal lamina propria harbors the largest population of plasma cells, most of which produce IgA. These Abs can bind to beneficial gut bacteria to reinforce intestinal homeostasis and provide protection against enteric pathogens.

Comparison of Omicron breakthrough infection versus monovalent SARS-CoV-2 intramuscular booster reveals differences in mucosal and systemic humoral immunity.

Our understanding of the quality of cellular and humoral immunity conferred by COVID-19 vaccination alone versus vaccination plus SARS-CoV-2 breakthrough (BT) infection remains incomplete. While the current (2023) SARS-CoV-2 immune landscape of Canadians is complex, in late 2021 most Canadians had either just received a third dose of COVID-19 vaccine, or had received their two-dose primary series and then experienced an Omicron BT. Herein we took advantage of this coincident timing to contrast cellular and humoral immunity conferred by three doses of vaccine versus two doses plus BT.

Species distribution and antifungal susceptibility profiles of clinical and environmental isolates from Mexico: A multicenter study.

spp. has emerged as an opportunistic etiological agent with clinical manifestations varying from localized infections to deep-seated systemic disease. It is also a phytopathogen of economic impact.

The Role of Helicobacter pylori and Small Intestinal Bacterial Overgrowth in Parkinson's Disease.

Parkinson's disease (PD) is a common neurodegenerative disorder whose etiology remains largely unexplained. Several studies have aimed to describe a causative effect in the interactions between the gastrointestinal tract and the brain, for both PD pathogenesis and disease course. However, the results have been controversial.

Severe strongyloidiasis: a systematic review and meta-analysis of 339 cases.

Strongyloidiasis is a parasitosis representing a significant public health problem in tropical countries. It is often asymptomatic in immunocompetent individuals but its mortality rate increases to approximately 87% in severe forms of the disease. We conducted a systematic review, including case reports and case series, of Strongyloides hyperinfection and dissemination from 1998 to 2020 searching PubMed, EBSCO and SciELO.

Systemic and mucosal IgA responses are variably induced in response to SARS-CoV-2 mRNA vaccination and are associated with protection against subsequent infection.

Although SARS-CoV-2 infects the upper respiratory tract, we know little about the amount, type, and kinetics of antibodies (Ab) generated in the oral cavity in response to COVID-19 vaccination. We collected serum and saliva samples from participants receiving two doses of mRNA COVID-19 vaccines and measured the level of anti-SARS-CoV-2 Ab. We detected anti-Spike and anti-Receptor Binding Domain (RBD) IgG and IgA, as well as anti-Spike/RBD associated secretory component in the saliva of most participants after dose 1.

Immunoglobulin A nephropathy is characterized by anticommensal humoral immune responses.

IgA nephropathy (IgAN) is a leading cause of kidney failure, yet little is known about the immunopathogenesis of this disease. IgAN is characterized by deposition of IgA in the kidney glomeruli, but the source and stimulus for IgA production are not known. Clinical and experimental data suggest a role for aberrant immune responses to mucosal microbiota in IgAN, and in some countries with high disease prevalence, tonsillectomy is regarded as standard-of-care therapy.

CCR6 Expression on B Cells Is Not Required for Clinical or Pathological Presentation of MOG Protein-Induced Experimental Autoimmune Encephalomyelitis despite an Altered Germinal Center Response.

B cells have been implicated in the pathogenesis of multiple sclerosis, but the mechanisms that guide B cell activation in the periphery and subsequent migration to the CNS remain incompletely understood. We previously showed that systemic inflammation induces an accumulation of B cells in the spleen in a CCR6/CCL20-dependent manner. In this study, we evaluated the role of CCR6/CCL20 in the context of myelin oligodendrocyte glycoprotein (MOG) protein-induced (B cell-dependent) experimental autoimmune encephalomyelitis (EAE).

Physiological characterization and molecular identification of some rare yeast species causing onychomycosis.

Introduction: Onychomycosis are infections with a variety of etiological agents. Although dermatophytes are responsible for most infections, yeasts are gaining importance as agents of these pathologies. The use of antifungals has increased the incidence of what had been considered rare or novel pathogens.

The Ins and Outs of Central Nervous System Inflammation-Lessons Learned from Multiple Sclerosis.

Multiple sclerosis (MS) is a chronic disease that is characterized by the inappropriate invasion of lymphocytes and monocytes into the central nervous system (CNS), where they orchestrate the demyelination of axons, leading to physical and cognitive disability. There are many reasons immunologists should be interested in MS. Aside from the fact that there is still significant unmet need for patients living with the progressive form of the disease, MS is a case study for how immune cells cross CNS barriers and subsequently interact with specialized tissue parenchymal cells.

B cell depletion therapies in autoimmune disease: advances and mechanistic insights.

In the past 15 years, B cells have been rediscovered to be not merely bystanders but rather active participants in autoimmune aetiology. This has been fuelled in part by the clinical success of B cell depletion therapies (BCDTs). Originally conceived as a method of eliminating cancerous B cells, BCDTs such as those targeting CD20, CD19 and BAFF are now used to treat autoimmune diseases, including systemic lupus erythematosus and multiple sclerosis.

Gut microbiota-specific IgA B cells traffic to the CNS in active multiple sclerosis.

Changes in gut microbiota composition and a diverse role of B cells have recently been implicated in multiple sclerosis (MS), a central nervous system (CNS) autoimmune disease. Immunoglobulin A (IgA) is a key regulator at the mucosal interface. However, whether gut microbiota shape IgA responses and what role IgA cells have in neuroinflammation are unknown.

Regulation of neuroinflammation by B cells and plasma cells.

The remarkable success of anti-CD20 B cell depletion therapies in reducing the burden of multiple sclerosis (MS) disease has prompted significant interest in how B cells contribute to neuroinflammation. Most focus has been on identifying pathogenic CD20 B cells. However, an increasing number of studies have also identified regulatory functions of B lineage cells, particularly the production of IL-10, as being associated with disease remission in anti-CD20-treated MS patients.

Persistence of serum and saliva antibody responses to SARS-CoV-2 spike antigens in COVID-19 patients.

While the antibody response to SARS-CoV-2 has been extensively studied in blood, relatively little is known about the antibody response in saliva and its relationship to systemic antibody levels. Here, we profiled by enzyme-linked immunosorbent assays (ELISAs) IgG, IgA and IgM responses to the SARS-CoV-2 spike protein (full length trimer) and its receptor-binding domain (RBD) in serum and saliva of acute and convalescent patients with laboratory-diagnosed COVID-19 ranging from 3-115 days post-symptom onset (PSO), compared to negative controls. Anti-SARS-CoV-2 antibody responses were readily detected in serum and saliva, with peak IgG levels attained by 16-30 days PSO.

Plasma Cells: From Cytokine Production to Regulation in Experimental Autoimmune Encephalomyelitis.

B cells are a critical arm of the adaptive immune system. After encounter with antigen, B cells are activated and differentiate into plasmablasts (PBs) and plasma cells (PCs). Although their frequency is low, PB/PCs can be found in all lymphoid organs including peripheral lymph nodes and spleen.

A comparative study of extracellular enzymes from chromoblastomycosis agents reveals the potential association of phospholipase with the severity of the lesions.

Chromoblastomycosis is a chronic, progressive subcutaneous mycosis that is endemic in tropical and subtropical countries. Cladophialophora carrionii and Fonsecaea pedrosoi are prevalent etiological agents. The potential role of the proteolytic activity of extracellular enzymes in these fungi and its relationship with the pathogenesis of the disease has not been proven.