Endosomal trafficking inhibitor EGA can control TLR7-mediated IFNα expression by human plasmacytoid dendritic cells.

Plasmacytoid dendritic cells (pDC) are the major producer of type 1 IFN in response to TLR7 agonists. Aberrant TLR7 activation and type 1 IFN expression by pDCs are linked to the pathogenesis of certain types of autoimmune diseases, including systemic lupus erythematosus (SLE). This study investigated the underlying mechanisms for TLR7-mediated cytokine expression by pDCs using a late endosome trafficking inhibitor, EGA (4-bromobenzaldehyde N-(2,6-dimethylphenyl) semicarbazone). We found that EGA treatment decreased IFNα expression by pDCs stimulated with imiquimod (R837), single-stranded RNA40, and influenza virus. EGA also decreased TNFα expression and secretion by R837-stimulated pDCs. Mechanistically, EGA treatment decreased phosphorylation of IKKα/ß, STAT1, and p38, and prolonged degradation of IκBα. Furthermore, EGA treatment decreased the colocalization of 3F, a substituted adenine TLR7 agonist, with LAMP1+ compartments in pDCs. EGA was also capable of diminishing IFNα expression by SLE pDCs treated with R837 or live PR8/A/34 influenza viruses. Therefore, we concluded that trafficking of TLR7 agonists to LAMP1+ compartments is important for IFNα expression by pDCs. Data from this study support additional examinations of the potential benefits of EGA in treating type 1 IFN-associated inflammatory diseases in the future.

Disruption of endosomal trafficking with EGA alters TLR9 cytokine response in human plasmacytoid dendritic cells.

Plasmacytoid dendritic cells (pDCs) exhibit bifurcated cytokine responses to TLR9 agonists, an IRF7-mediated type 1 IFN response or a pro-inflammatory cytokine response via the activation of NF-κB. This bifurcated response has been hypothesized to result from either distinct signaling endosomes or endo-lysosomal trafficking delay of TLR9 agonists allowing for autocrine signaling to affect outcomes. Utilizing the late endosome trafficking inhibitor, EGA, we assessed the bifurcated cytokine responses of pDCs to TLR9 stimulation. EGA treatment of pDCs diminished both IFNα and pro-inflammatory cytokine expression induced by CpG DNAs (D- and K-type), CpG-DNAs complexed with DOTAP, and genomic DNAs complexed with LL37. Mechanistically, EGA suppressed phosphorylation of IKKα/ß, STAT1, Akt, and p38, and decreased colocalization of CpG oligodeoxynucleotides with LAMP+ endo-lysosomes. EGA also diminished type 1 IFN expression by pDCs from systemic lupus erythematosus patients. Therefore, our findings help understand mechanisms for the bifurcated cytokine responses by pDCs and support future examination of the potential benefit of EGA in treating type 1 IFN-associated inflammatory diseases in the future.

Evaluation of the Safety of Calcitonin Gene-Related Peptide Antagonists for Migraine Treatment Among Adults With Raynaud Phenomenon.

Importance: Calcitonin gene-related peptide (CGRP) antagonists have demonstrated tremendous promise in migraine management. However, these medications decrease reflex vasodilatory response, which may lead to exacerbation of microvascular disease in susceptible patients, such as patients with Raynaud phenomenon (RP). Objective: To investigate the microvascular complications of CGRP antagonists in patients with underlying RP. Design, Setting, and Participants: This retrospective cohort study was performed from May 18, 2018, to September 15, 2020, in Mayo Clinic Health System patients with Raynaud phenomenon while undergoing CGRP antagonist therapy to treat migraine. Inclusion criteria were age older than 18 years, history of migraine, past or current treatment with CGRP antagonists, and diagnosis of primary or secondary RP. Exposure: Treatment with CGRP antagonists. Main Outcomes and Measures: The main outcome measure was microvascular complications (eg, worsening RP, digital ulcerations, and gangrenous necrosis) after initiation of treatment with a CGRP antagonist. Patient demographic and clinical characteristics were compared between those who experienced complications and those who did not. Results: A total of 169 patients (163 [96.4%] female; 151 [89.3%] non-Hispanic White; mean [SD] age, 46 [13] years) were identified. Of the 169 patients, 9 (5.3%) exhibited microvascular complications, ranging from worsening RP to gangrene and autonecrosis that required distal digit amputation. Comparative analysis did not find statistically significant differences in demographic or clinical characteristics between the 2 cohorts. All 9 patients with complications were female (mean [SD] age, 40 [12] years). Five of the 9 patients (55.6%) had previously diagnosed RP; in 3 the RP was primary, and 2 it was secondary to scleroderma. The other 4 patients (44.4%) were newly diagnosed with RP. Eight of the 9 patients (88.9%) had chronic migraine; 4 had migraine with aura, and 5 had migraine without aura. The CGRP antagonist agents temporally associated with the microvascular complications included galcanezumab (in 3 patients), erenumab (in 5 patients), and fremanezumab (in 1 patient). Conclusions and Relevance: The results of this study indicate that microvascular complications of CGRP antagonist use in patients with underlying RP are uncommon. The incidence of serious adverse events, although rare, warrant caution when considering the use of these agents in patients with RP.

Myeloablative Autologous Stem-Cell Transplantation for Severe Scleroderma.

BACKGROUND: Despite current therapies, diffuse cutaneous systemic sclerosis (scleroderma) often has a devastating outcome. We compared myeloablative CD34+ selected autologous hematopoietic stem-cell transplantation with immunosuppression by means of 12 monthly infusions of cyclophosphamide in patients with scleroderma. METHODS: We randomly assigned adults (18 to 69 years of age) with severe scleroderma to undergo myeloablative autologous stem-cell transplantation (36 participants) or to receive cyclophosphamide (39 participants). The primary end point was a global rank composite score comparing participants with each other on the basis of a hierarchy of disease features assessed at 54 months: death, event-free survival (survival without respiratory, renal, or cardiac failure), forced vital capacity, the score on the Disability Index of the Health Assessment Questionnaire, and the modified Rodnan skin score. RESULTS: In the intention-to-treat population, global rank composite scores at 54 months showed the superiority of transplantation (67% of 1404 pairwise comparisons favored transplantation and 33% favored cyclophosphamide, P=0.01). In the per-protocol population (participants who received a transplant or completed ≥9 doses of cyclophosphamide), the rate of event-free survival at 54 months was 79% in the transplantation group and 50% in the cyclophosphamide group (P=0.02). At 72 months, Kaplan-Meier estimates of event-free survival (74% vs. 47%) and overall survival (86% vs. 51%) also favored transplantation (P=0.03 and 0.02, respectively). A total of 9% of the participants in the transplantation group had initiated disease-modifying antirheumatic drugs (DMARDs) by 54 months, as compared with 44% of those in the cyclophosphamide group (P=0.001). Treatment-related mortality in the transplantation group was 3% at 54 months and 6% at 72 months, as compared with 0% in the cyclophosphamide group. CONCLUSIONS: Myeloablative autologous hematopoietic stem-cell transplantation achieved long-term benefits in patients with scleroderma, including improved event-free and overall survival, at a cost of increased expected toxicity. Rates of treatment-related death and post-transplantation use of DMARDs were lower than those in previous reports of nonmyeloablative transplantation. (Funded by the National Institute of Allergy and Infectious Diseases and the National Institutes of Health; ClinicalTrials.gov number, NCT00114530 .).

The Impact of Pelvic Floor and Lower Gastrointestinal Symptoms on Quality of Life in Women With Systemic Sclerosis.

BACKGROUND: Systemic sclerosis (SSc) patients with gastrointestinal (GI) involvement have a lower quality of life (QoL) and while the impact of upper GI symptoms on QoL in SSc patients has been described few data exist on the presence and impact of lower gastrointestinal (LGI) and pelvic floor symptoms in SSc. Our goal was to assess the prevalence of these symptoms in women with SSc and evaluate their impact on QoL. A secondary hypothesis was that the impact of LGI symptoms on QoL is mediated by depression. STUDY: Women with SSc (n=175) attending an outpatient scleroderma clinic completed multiple validated questionnaires. Pelvic floor and LGI symptoms included fecal incontinence (FI), urinary incontinence (UI), dual incontinence (DI), chronic constipation, diarrhea, and pelvic pain. The Student t tests adjusted for multiple comparisons were used to evaluate group differences at the 0.05 level. RESULTS: Complete data were available for 160 women. FI was reported by 65, UI by 64, DI by 40, chronic constipation by 94, diarrhea by 82, and pelvic pain by 35 of SSc patients. Overall QoL was reduced in SSc patients with FI (0.96 vs. 0.63; P=0.007), UI (0.96 vs. 0.65; P=0.01), DI (1.11 vs. 0.67; P=0.002), and pelvic pain (1.01 vs. 0.70; P=0.04). Antidepressant use was reported by 26%. The negative impact on QoL in patients with pelvic floor symptoms was partially mediated by depression. CONCLUSIONS: Women with SSc suffer from an increased prevalence of LGI and pelvic floor symptoms including FI, UI, diarrhea, constipation, and pelvic pain and this effect seems to be partially mediated by depression.

Philip S. Hench's rheumatology axiomatic generalizations.

Philip S. Hench, MD, the first Mayo Clinic rheumatologist, came to Mayo Clinic in 1921. Because of his efforts in patient care, education, and research, and those of his colleagues, Mayo Clinic has been considered the first academic rheumatology center established in the United States. An early, popular lecture he gave to the internal medicine residents was an important and unique part of the rheumatology education program and was entitled "Axiomatic Generalizations Useful in the Diagnosis of Rheumatic Diseases." We review the axioms in light of the status of rheumatology in the 1920s and 1930s when they were written, and assess their relevance today, 70 to 80 years later.