Regular exercise promotes whole-body health and prevents disease, but the underlying molecular mechanisms are incompletely understood^1–3. Here, the Molecular Transducers of Physical Activity Consortium⁴ profiled the temporal transcriptome, proteome, metabolome, lipidome, phosphoproteome, acetylproteome, ubiquitylproteome, epigenome and immunome in whole blood, plasma and 18 solid tissues in male and female Rattus norvegicus over eight weeks of endurance exercise training. The resulting data compendium encompasses 9,466 assays across 19 tissues, 25 molecular platforms and 4 training time points. Thousands of shared and tissue-specific molecular alterations were identified, with sex differences found in multiple tissues. Temporal multi-omic and multi-tissue analyses revealed expansive biological insights into the adaptive responses to endurance training, including widespread regulation of immune, metabolic, stress response and mitochondrial pathways. Many changes were relevant to human health, including non-alcoholic fatty liver disease, inflammatory bowel disease, cardiovascular health and tissue injury and recovery. The data and analyses presented in this study will serve as valuable resources for understanding and exploring the multi-tissue molecular effects of endurance training and are provided in a public repository (https://motrpac-data.org/).

Objective To use the large dataset from the Tysabri Outreach: Unified Commitment to Health (TOUCH) program to compare progressive multifocal leukoencephalopathy (PML) risk with natalizumab extended interval dosing (EID) vs standard interval dosing (SID) in patients with multiple sclerosis (MS). Methods This retrospective cohort study included anti-JC virus antibody-positive patients (n = 35,521) in the TOUCH database as of June 1, 2017. The effect of EID on PML risk was evaluated with 3 planned analyses using Kaplan-Meier methods stratified by prior immunosuppressant use. Risk of PML was analyzed by Cox regression adjusted for age, sex, prior immunosuppressants, time since natalizumab initiation, and cumulative number of infusions. Results This study included 35,521 patients (primary analysis: 1,988 EID, 13,132 SID; secondary analysis: 3,331 EID, 15,424 SID; tertiary analysis: 815 EID, 23,168 SID). Mean average dosing intervals were 35.0 to 43.0 and 29.8 to 30.5 days for the EID and SID cohorts, respectively. Hazard ratios (95% confidence intervals) of PML risk for EID vs SID were 0.06 (0.01–0.22, p < 0.001) and 0.12 (0.05–0.29, p < 0.001) for the primary and secondary analyses, respectively. Relative risk reductions were 94% and 88% in favor of EID for the primary and secondary analyses, respectively. The tertiary analysis included no cases of PML with EID. Conclusion Natalizumab EID is associated with clinically and statistically significantly lower PML risk than SID. Classification of evidence This study provides Class III evidence that for patients with MS, natalizumab EID is associated with a lower PML risk than SID.

Immunophenotypes in lymphoproliferative diseases (LPD) are prognostically significant, yet causative factors for these conditions, and specifically those associated with heritable risk, remain elusive. The full spectrum of LPD seen in humans occurs in dogs, but the incidence and lifetime risk of naturally occurring LPD differs among dog breeds. Taking advantage of the limited genetic heterogeneity that exists within dog breeds, we tested the hypothesis that the prevalence of LPD immunophenotypes would differ among different breeds. The sample population included 1,263 dogs representing 87 breeds. Immunophenotype was determined by the presence of clonal rearrangements of immunoglobulin heavy chain or T-cell receptor γ chain. The probability of observing the number of B-cell or T-cell tumors in a particular breed or breed group was compared with three reference populations. Significance was computed using χ2 test, and logistic regression was used to confirm binomial predictions. The data show that, among 87 breeds tested, 15 showed significant differences from the prevalence of LPD immunophenotypes seen across the dog population as a whole. More significantly, elevated risk for T-cell LPD seems to have arisen ancestrally and is retained in related breed groups, whereas increased risk for B-cell disease may stem from different risk factors, or combinations of risk factors, arising during the process of breed derivation and selection. The data show that domestic dogs provide a unique and valuable resource to define factors that mediate risk as well as genes involved in the initiation of B-cell and T-cell LPD.

PURPOSE: Patients with neurofibromatosis type 1 (NF1) frequently develop plexiform neurofibromas (PNs), which can cause significant morbidity. We performed a phase II trial of the MAPK/ERK kinase inhibitor, mirdametinib (PD-0325901), in patients with NF1 and inoperable PNs. The primary objective was response rate based on volumetric magnetic resonance imaging analysis. METHODS: Inclusion criteria included age ≥ 16 years and a PN that was either progressive or causing significant morbidity. First-dose pharmacokinetics were performed. Patients completed patient-reported outcome measures. Patients received mirdametinib by mouth twice a day at 2 mg/m²/dose (maximum dose = 4 mg twice a day) in a 3-week on/1-week off sequence. Each course was 4 weeks in duration. Evaluations were performed after four courses for the first year and then after every six courses. Patients could receive a maximum of 24 total courses. RESULTS: Nineteen patients were enrolled, and all 19 received mirdametinib. The median age was 24 years (range, 16-39 years); the median baseline tumor volume was 363.8 mL (range, 3.9-5,161 mL). Eight of the 19 patients (42%) achieved a partial response of the target PN by course 12, and 10 (53%) had stable disease. One patient (5%) developed progressive disease at course 8. Significant and durable decreases were observed in pain ratings. CONCLUSION: To our knowledge, this analysis represents the first characterization of the activity and pharmacokinetics of mirdametinib in patients with NF1 and PNs and is the first published response study for MAPK/ERK kinase inhibitors in adults with NF1 and PNs. Mirdametinib given at 2 mg/m²/dose (maximum dose, 4 mg) twice daily in a 3-week on/1-week off sequence resulted in a 42% partial response rate with preliminary evidence of reduction in pain.

Data are limited for mortality and comorbidities in patients with multiple sclerosis (MS). Compare mortality rates and event rates for comorbidities in MS (n=15,684) and non-MS (n=78,420) cohorts from the US Department of Defense (DoD) database. Comorbidities and all-cause mortality were assessed using the database. Causes of death (CoDs) were assessed through linkage with the National Death Index. Cohorts were compared using mortality (MRR) and event (ERR) rate ratios. All-cause mortality was 2.9-fold higher in the MS versus non-MS cohort (MRR, 95% confidence interval [CI]: 2.9, 2.7-3.2). Frequent CoDs in the MS versus non-MS cohort were infectious diseases (6.2, 4.2-9.4), diseases of the nervous (5.8, 3.7-9.0), respiratory (5.0, 3.9-6.4) and circulatory (2.1, 1.7-2.7) systems and suicide (2.6, 1.3-5.2). Comorbidities including sepsis (ERR, 95% CI: 5.7, 5.1-6.3), ischemic stroke (3.8, 3.5-4.2), attempted suicide (2.4, 1.3-4.5) and ulcerative colitis (2.0, 1.7-2.3), were higher in the MS versus non-MS cohort. The rate of cancers was also higher in the MS versus the non-MS cohort, including lymphoproliferative disorders (2.2, 1.9-2.6) and melanoma (1.7, 1.4-2.0). Rates of mortality and several comorbidities are higher in the MS versus non-MS cohort. Early recognition and management of comorbidities may reduce premature mortality and improve quality of life in patients with MS.

Objective To determine the activation status and cytokine profiles of CD4⁺ T cells, CD8⁺ T cells, and CD19⁺ B cells from patients with early-stage Parkinson disease (PD) compared with healthy controls (HCs). Methods Peripheral blood samples from 41 patients with early-stage PD and 40 HCs were evaluated. Peripheral blood mononuclear cells were analyzed by flow cytometry for surface markers and intracellular cytokine production. Correlations of immunologic changes and clinical parameters were analyzed. Results Adaptive immunity plays a role in the pathogenesis of PD, yet the contribution of T cells and B cells, especially cytokine production by these cells, is poorly understood. We demonstrate that naive CD4⁺ and naive CD8⁺ T cells are significantly decreased in patients with PD, whereas central memory CD4⁺ T cells are significantly increased in patients with PD. Furthermore, IL-17–producing CD4⁺ Th17 cells, IL-4–producing CD4⁺ Th2 cells, and IFN-γ–producing CD8⁺ T cells are significantly increased in patients with PD. Regarding B cells, we observed a decrease in naive B cells and an increase in nonswitched memory and double-negative B cells. As well, TNF-α–producing CD19⁺ B cells were significantly increased in patients with PD. Notably, some of the changes observed in CD4⁺ T cells and B cells were associated with clinical motor disease severity. Conclusions These findings suggest that alterations in the adaptive immune system may promote clinical disease in PD by skewing to a more proinflammatory state in the early-stage PD patient cohort. Our study may shed light on potential immunotherapies targeting dysregulated CD4⁺ T cells, CD8⁺ T cells, and CD19⁺ B cells in patients with PD.