Microalgae as an Efficient Vehicle for the Production and Targeted Delivery of Therapeutic Glycoproteins against SARS-CoV-2 Variants.

Severe acute respiratory syndrome-Coronavirus 2 (SARS-CoV-2) can infect various human organs, including the respiratory, circulatory, nervous, and gastrointestinal ones. The virus is internalized into human cells by binding to the human angiotensin-converting enzyme 2 (ACE2) receptor through its spike protein (S-glycoprotein). As S-glycoprotein is required for the attachment and entry into the human target cells, it is the primary mediator of SARS-CoV-2 infectivity.

IgG Glycosylation from Patients with Pemphigus Treated with Rituximab.

Pemphigus is a life-threatening auto-immune blistering disease of the skin and mucous membrane that is caused by the production of auto-antibodies (auto-Abs) directed against adhesion proteins: desmoglein 1 and 3. We demonstrated in the "Ritux3" trial, the high efficacy of rituximab, an anti-CD20 recombinant monoclonal antibody, as the first-line treatment for pemphigus. However, 25% of patients relapsed during the six-month period after rituximab treatment.

Evaluation of Clinical Relevance and Biological Effects of Antirituximab Antibodies in Patients With Pemphigus.

Importance: The clinical relevance of antirituximab antibodies (ARAs) in patients with pemphigus who are treated with rituximab (RTX) is currently unknown.

Objective: To determine the prevalence of ARAs in patients with pemphigus who are treated with RTX and their association with complete remission (CR) and relapse.

Design, Setting, And Participants: This post hoc analysis of the Ritux3 trial was conducted from January 2010 to December 2015 in 25 dermatology departments in France and included 42 patients with moderate-to-severe pemphigus who were randomized to receive treatment with RTX.

FcRn Antagonism Leads to a Decrease of Desmoglein-Specific B Cells: Secondary Analysis of a Phase 2 Study of Efgartigimod in Pemphigus Vulgaris and Pemphigus Foliaceus.

Background: Immunoglobulin G (IgG) levels are maintained by the IgG-recycling neonatal Fc-receptor (FcRn). Pemphigus vulgaris and pemphigus foliaceus are debilitating autoimmune disorders triggered by IgG autoantibodies against mucosal and epidermal desmogleins. Recently, a phase 2 clinical trial (NCT03334058; https://clinicaltrials.

The Diversity of Serum Anti-DSG3 IgG Subclasses Has a Major Impact on Pemphigus Activity and Is Predictive of Relapses After Treatment With Rituximab.

Introduction: We studied the distribution and pathogenicity of anti-DSG3 IgG subclasses during the course of pemphigus vulgaris (PV).

Methods: We longitudinally studied the distribution of anti-DSG3 IgG subclasses (before after treatment) in sera from PV patients, using an addressable-laser bead immunoassay (ALBIA). The pathogenicity of corresponding sera was tested using keratinocyte dissociation and immunofluorescence assays.

Longitudinal Pathogenic Properties and -Glycosylation Profile of Antibodies from Patients with Pemphigus after Corticosteroid Treatment.

Pemphigus vulgaris is an autoimmune disease that occurs due to pathogenic autoantibodies that recognize the following epidermal adhesion proteins: desmogleins. Systemic corticosteroids usually decrease the titers of anti-desmoglein autoantibodies and improve patients' conditions. Since modifications of IgG -glycosylation have been described in some autoimmune diseases, we hypothesized that changes in the pathogenic activity of pemphigus IgG could be related to changes in their -glycosylation profile.

Modifications of the BAFF/BAFF-Receptor Axis in Patients With Pemphigus Treated With Rituximab Versus Standard Corticosteroid Regimen.

The efficacy of the B-cell-depleting agent rituximab has been reported in immune diseases but relapses are frequent, suggesting the need for repeated infusions. The B-cell activating factor (BAFF) is an important factor for B cell survival, class switch recombination and selection of autoreactive B cells, as well as maintaining long-lived plasma cells. It has been hypothesized that relapses after rituximab might be due to the increase of serum BAFF levels.

Rituximab and Corticosteroid Effect on Desmoglein-Specific B Cells and Desmoglein-Specific T Follicular Helper Cells in Pemphigus.

Pemphigus is an autoimmune blistering disease mediated by autoantibodies directed against desmogleins (DSGs). We recently showed that first-line treatment with rituximab (RTX) enables more patients to achieve long-lasting remission off therapy than corticosteroids alone. To understand the immunological mechanisms that mediate long-lasting clinical remission after RTX treatment, we analyzed the phenotype of DSG-specific memory B cells and DSG-specific T follicular helper cells by flow cytometry and measured antibody-secreting cells by enzyme-linked immune absorbent spot in patients treated with corticosteroids alone or RTX.

Methods to Study the Transcriptome of Regulatory B Cells.

Regulatory B cells do not constitute a distinct cell lineage because no unique marker or set of markers can exclusively identify neither murine nor human regulatory B cells, and efficient IL-10 production is their only known distinguishing feature. After purification of IL-10-secreting B cells, one may want to characterize them by analyzing their gene expression profile. This goal can be achieved by using different technologies: RT-qPCR, microarrays, Nanostring's nCounter technology, Biomark HD are techniques that will allow you to analyze their gene expression, whether in a targeted (RT-qPCR), extended but targeted (Nanostring's nCounter technology, Biomark HD) or exhaustive (Microarray) way.

Factors Associated With Short-term Relapse in Patients With Pemphigus Who Receive Rituximab as First-line Therapy: A Post Hoc Analysis of a Randomized Clinical Trial.

Importance: Rituximab and short-term corticosteroid therapy are the criterion standard treatments for patients with newly diagnosed moderate to severe pemphigus.

Objective: To examine factors associated with short-term relapse in patients with pemphigus treated with rituximab.

Design, Setting, And Participants: This post hoc analysis of a randomized clinical trial (Comparison Between Rituximab Treatment and Oral Corticosteroid Treatment in Patients With Pemphigus [RITUX 3]) conducted from January 1, 2010, to December 31, 2015, included patients from 20 dermatology departments of tertiary care centers in France from the RITUX 3 trial and 3 newly diagnosed patients treated according to the trial protocol.

CD11c B Cells Are Mainly Memory Cells, Precursors of Antibody Secreting Cells in Healthy Donors.

CD11c B cells have been reported to be increased in autoimmune diseases, but they are detected in the blood of healthy individuals as well. We aimed to characterize CD11c B cells from healthy donors by flow cytometry, microarray analysis, and functional assays. Here, we report that CD11c B cells are a distinct subpopulation of B cells, enriched in the memory subpopulation even if their phenotype is heterogeneous, with overexpression of genes involved in B-cell activation and differentiation as well as in antigen presentation.

Author Correction: B-cell depletion induces a shift in self antigen specific B-cell repertoire and cytokine pattern in patients with bullous pemphigoid.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Rituximab is an effective treatment in patients with pemphigus vulgaris and demonstrates a steroid-sparing effect.

Background: Corticosteroids (CS) with or without adjuvant immunosuppressant agents are standard treatment for pemphigus vulgaris (PV). The efficacy of adjuvant therapies in minimizing steroid-related adverse events (AEs) is unproven.

Objectives: To utilize data collected in a French investigator-initiated, phase III, open-label, randomized controlled trial to demonstrate the efficacy and safety of rituximab and seek approval for its use in PV.

Modifications of the Transcriptomic Profile of Autoreactive B Cells From Pemphigus Patients After Treatment With Rituximab or a Standard Corticosteroid Regimen.

Pemphigus Vulgaris is an autoimmune disease of the skin and mucous membranes, which is due to the production of pathogenic autoantibodies targeting desmoglein (DSG) 1 and 3, which are adhesion proteins of the keratinocytes. Rituximab is an anti-CD20 mAb which induces a prolonged depletion of blood B cells. We recently showed that rituximab was more effective than a standard oral corticosteroid (CS) treatment, allowing 90% of patients to achieve complete remission (CR).

B-cell depletion induces a shift in self antigen specific B-cell repertoire and cytokine pattern in patients with bullous pemphigoid.

Bullous Pemphigoid is the most common auto-immune bullous skin disease. It is characterized by the production of auto-antibodies directed against 2 proteins of the hemi-desmosome (BP180 and BP230). We assessed the efficacy and mechanisms of action of rituximab, an anti-CD20 monoclonal antibody, in 17 patients with severe and relapsing type of bullous pemphigoid.

Long-term remissions of severe pemphigus after rituximab therapy are associated with prolonged failure of desmoglein B cell response.

Pemphigus is a severe blistering condition of the skin and mucosa caused by autoantibodies directed against desmogleins, which are a type of keratinocyte adhesion protein. B cell depletion by rituximab has short-term efficacy against pemphigus. We aimed to assess the long-term course of pemphigus patients after B cell depletion and to understand the immunological mechanisms that mediate long-lasting remissions.

Drug Reaction with Eosinophilia and Systemic Symptoms: an update on pathogenesis.

The syndrome termed 'Drug Reaction with Eosinophilia and Systemic Symptoms' (DRESS) is an unpredictable, life-threatening condition associated with adverse reactions to therapy. Although the etiology of DRESS is poorly understood, genetic susceptibility markers have been identified within the HLA complex and there are several prevailing models of pathogenesis. Modification of host antigens by haptens (drugs or their metabolites), or non-covalent drug binding to endogenous proteins (the p-i concept), may drive pro-inflammatory immune responses in patients.

Severe drug eruptions revisited.

Genetic and non-genetic factors can alter the action of a medicinal drug, resulting in a wide range of responses in different individuals. Among the many potential side effects of therapies, a drug eruption is an adverse drug reaction in the skin. Genetic associations between HLA haplotype and drug eruption have been reported, and immune responses against latent herpesvirus have also been implicated in some forms of this syndrome.

IL-10 produced by activated human B cells regulates CD4(+) T-cell activation in vitro.

IL-10-producing regulatory B cells have been identified in mice and shown to downregulate inflammation, making them potentially important for maintenance of tolerance. In this study, we isolated B cells from human blood and spleen, and showed that after a short period of ex vivo stimulation a number of these cells produced IL-10. The IL-10-producing B cells did not fall within a single clearly defined subpopulation, but were enriched in both the memory (CD27(+)) and the transitional (CD38(high)) B-cell compartments.