Tocilizumab as a potential treatment in Schnitzler syndrome

Dermatologic Manifestations of Noninflammasome-Mediated Autoinflammatory Diseases

Autoinflammatory diseases (AIDs) arise from disturbances that alter interactions of immune cells and tissues. They give rise to prominent (auto)inflammation in the absence of aberrant autoantibodies and/or autoreactive T cells. AIDs that are predominantly caused by changes in the inflammasome pathways, such as the NLRP3- or pyrin-associated inflammasome, have gained substantial attention over the last years. However, AIDs resulting primarily from other changes in the defense system of the innate immune system are less well-studied. These noninflammasome-mediated AIDs relate to, for example, disturbance in the TNF or IFN signaling pathways or aberrations in genes affecting the IL-1RA. The spectrum of clinical signs and symptoms of these conditions is vast. Thus, recognizing early cutaneous signs constitutes an important step in differential diagnoses for dermatologists and other physicians. This review provides an overview of the pathogenesis, clinical presentation, and available treatment options highlighting dermatologic aspects of noninflammasome-mediated AIDs.

Cytokine Signature in Schnitzler Syndrome: Proinflammatory Cytokine Production Associated to Th Suppression

Background

Schnitzler syndrome (SchS) is a rare autoinflammatory disease characterized by urticarial exanthema, bone and joint alterations, fever and monoclonal IgM gammopathy. Overactivation of the interleukin(IL)-1 system is reported, even though the exact pathophysiological pathways remain unknown.

Objective

To determine ex vivo cytokine profiles of Peripheral Blood Mononuclear Cells (PBMCs) from SchS patients prior to treatment and after initiation of anti-IL-1 therapy (anakinra). The sera cytokine profile was studied in parallel.

Methods

We collected blood samples from thirty-six untreated or treated SchS. PBMCs were cultured with and without LPS or anti-CD3/CD28. Cytokine levels were evaluated in serum and cell culture supernatants using Luminex technology.

Results

Spontaneous TNFα, IL-6, IL-1β, IL-1α, and IL-1RA release by PBMCs of SchS patients were higher than in controls. LPS-stimulation further induced the secretion of these cytokines. In contrast, after T-cell stimulation, TNFα, IL-10, IFNγ, IL-17A, and IL-4 production decreased in SchS patients compared to healthy controls, but less in treated patients. Whereas IL-1β serum level was not detected in most sera, IL-6, IL-10, and TNFα serum levels were higher in patients with SchS and IFNγ and IL-4 levels were lower. Of note, IL-6 decreased after treatment in SchS (p = 0.04).

Conclusion

Our data strengthen the hypothesis of myeloid inflammation in SchS, mediated in particular by IL-1β, TNFα, and IL-6, associated with overproduction of the inhibitors IL-1RA and IL-10. In contrast, we observed a loss of Th1, Th2, and Th17 cell functionalities that tends to be reversed by anakinra.

A Review of Recent Advances Using Tocilizumab in the Treatment of Rheumatic Diseases

Tocilizumab (TCZ) is the first humanized anti-interleukin-6 (IL-6) receptor monoclonal antibody approved for the treatment of patients with rheumatoid arthritis (RA), Castleman's disease, polyarticular and systemic juvenile idiopathic arthritis, and, most recently, giant cell arteritis as well as for the treatment of chimeric antigen receptor T cell therapy-induced cytokine release syndrome. The global clinical development program for TCZ provides a wealth of clinical data on intravenous TCZ, and more recent studies in patients with RA have provided evidence characterizing the role of intravenous TCZ as monotherapy in early disease and led to the introduction of a subcutaneous formulation of TCZ. In addition, recently published open-label extension and observational studies continue to support the long-term efficacy and safety of TCZ in both clinical trial and real-world settings. Given the involvement of IL-6-mediated signaling in inflammatory disorders, TCZ is also being investigated in other immunological diseases. In particular, a phase 2 trial on the safety and efficacy of subcutaneous TCZ in adults with systemic sclerosis shows clinically relevant improvements in skin sclerosis and lung function in these patients. Another anti-IL-6 receptor agent, sarilumab, targeting the IL6 receptor alpha subunit, was recently approved for the treatment of patients with RA, although long-term data for this biologic are not yet published. In this article we review the placement of TCZ in current treatment guidelines; recent clinical trial data, including quality of life in patients with RA; recent updates to the TCZ safety profile; recent investigations of TCZ in other immunological diseases; and the clinical development of other novel IL-6-targeted agents.

Schnitzler's syndrome: a case report

Schnitzler's syndrome is an extremely rare entity that poses a challenge for the clinician not only due to its difficult diagnosis but also due to its management. In this article we report a new case and briefly review the current treatment options.

Genetics of asthma susceptibility and severity

This article summarizes major findings in genome-wide studies of asthma susceptibility and severity. Two large meta-analyses identified four chromosomal regions which were consistently associated with development of asthma. Genes that are associated with asthma subphenotypes such as lung function, biomarker levels, and asthma therapeutic responses can provide insight into mechanisms of asthma severity and disease progression. Future genetic studies will incorporate sequencing in comprehensively phenotyped asthmatics to lead to the development of personalized therapy.

The IL6R variation Asp(358)Ala is a potential modifier of lung function in subjects with asthma

BACKGROUND

The IL6R single nucleotide polymorphism (SNP) rs4129267 has recently been identified as an asthma susceptibility locus in subjects of European ancestry but has not been characterized with respect to asthma severity. The SNP rs4129267 is in linkage disequilibrium (r(2) = 1) with the IL6R coding SNP rs2228145 (Asp(358)Ala). This IL6R coding change increases IL-6 receptor (IL-6R) shedding and promotes IL-6 transsignaling.

OBJECTIVES

We sought to evaluate the IL6R SNP rs2228145 with respect to asthma severity phenotypes.

METHODS

The IL6R SNP rs2228145 was evaluated in subjects of European ancestry with asthma from the Severe Asthma Research Program (SARP). Lung function associations were replicated in the Collaborative Study on the Genetics of Asthma (CSGA) cohort. Serum soluble IL-6R levels were measured in subjects from SARP. Immunohistochemistry was used to qualitatively evaluate IL-6R protein expression in bronchoalveolar lavage cells and endobronchial biopsies.

RESULTS

The minor C allele of IL6R SNP rs2228145 was associated with a lower percent predicted FEV(1) in the SARP cohort (P= .005), the CSGA cohort (P= .008), and in a combined cohort analysis (P= .003). Additional associations with percent predicted forced vital capacity (FVC), FEV(1)/FVC ratio, and PC(20) were observed. The rs2228145 C allele (Ala(358)) was more frequent in severe asthma phenotypic clusters. Elevated serum soluble IL-6R levels were associated with lower percent predicted FEV(1) (P= .02) and lower percent predicted FVC (P= .008) (n= 146). IL-6R protein expression was observed in bronchoalveolar lavage macrophages, airway epithelium, vascular endothelium, and airway smooth muscle.

CONCLUSIONS

The IL6R coding SNP rs2228145 (Asp(358)Ala) is a potential modifier of lung function in subjects with asthma and might identify subjects at risk for more severe asthma. IL-6 transsignaling might have a pathogenic role in the lung.