COMBAT-MS: A Population-Based Observational Cohort Study Addressing the Benefit-Risk Balance of Multiple Sclerosis Therapies Compared with Rituximab.

OBJECTIVE: To assess comparative effectiveness, safety, and tolerability of off-label rituximab, compared with frequently used therapies approved for multiple sclerosis (MS). METHODS: A Swedish cohort study of persons with relapsing-remitting MS, age 18 to 75 years at inclusion and with a first therapy start or a first therapy switch between 2011 and 2018. Low-dose rituximab was compared with MS-approved therapies. Primary outcomes were proportions with 12 months confirmed disability worsening and change in MS Impact Scale-29 (MSIS-29) scores, respectively. Secondary endpoints included relapses, therapy discontinuation, and serious adverse events. Analyses used an intention-to-treat approach and were adjusted for demographics, MS features, and health characteristics. RESULTS: We included 2,449 participants as first therapy start and 2,463 as first therapy switch. Proportions with disability worsening at 3 years were 9.1% for rituximab as first therapy and 5.1% after therapy switch, with no differences to MS-approved comparators. Worsening on rituximab was mostly independent of relapses. MSIS-29 with rituximab at 3 years improved by 1.3/8.4 points (physical/psychological) for first disease-modifying therapy (DMT) and 0.4/3.6 for DMT switch, and was mostly similar across therapies. Rituximab had lower relapse rates and higher therapy persistence in both groups. The rate of hospital-treated infections was higher with rituximab after a therapy switch, but not as a first therapy. INTERPRETATION: This population-based real-world cohort study found low rates of disability progression, mostly independent of relapses, and without significant differences between rituximab and MS-approved comparators. Rituximab led to lower rates of inflammatory activity and higher treatment persistence, but was associated with an increased rate of serious infections. ANN NEUROL 2024.

Morbidity and mortality among children, adolescents, and young adults with cancer over six decades: a Swedish population-based cohort study (the Rebuc study).

Background: Despite progress in managing cancer in children, adolescents, and young adults (CAYAs), persistent complications may impact their quality of life. This study covers the morbidity and mortality, among CAYAs, with the aim to investigate the influence of socioeconomic factors on outcomes. Methods: This retrospective matched cohort study included the entire Swedish population of individuals under 25 with cancer 1958-2021. The population was identified from the Cancer Register, and controls were paired 1:5 based on age, sex, and residence. Multiple registers provided data on morbidity, mortality, and demographics. Findings: This survey covering 63 years, identified 65,173 CAYAs and matched controls, a total of 378,108 individuals (74% females). CAYAs exhibited a 3.04-times higher risk for subsequent cancer (Odds ratio (OR) 95% confidence interval (CI) 2.92-3.17, p < 0.0001), a 1.23-times higher risk for cardiovascular disease (OR 95% CI 1.20-1.26, p < 0.0001), and a 1.41-times higher risk for external affliction (OR 95% CI 1.34-1.49, p < 0.0001). CAYAs had a higher mortality hazard, and after adjusting for socioeconomic factors, males, individuals born outside Europe, and those with greater sick-leave had a higher association with mortality, while education and marriage showed a beneficial association. Interpretation: The Rebuc study, showed an increased risk for serious complications among young cancer patients in Sweden. Patient-specific variables, demographics, and socioeconomic factors influenced mortality. These results underscore the impact of cancer on the health and lifespan of young individuals and the necessity for further research to address socioeconomic disparities in cancer care. Funding: Grants from the Medical Research Council of Southeast Sweden (FORSS), ALF Grants, Region Ostergotland, and The Swedish Childhood Cancer Fund.

Trajectories of cognitive processing speed and physical disability over 11 years following initiation of a first multiple sclerosis disease-modulating therapy.

BACKGROUND: We analysed the COMparison Between All immunoTherapies for Multiple Sclerosis (NCT03193866), a Swedish nationwide observational study in relapsing-remitting multiple sclerosis (RRMS), to identify trajectories of processing speed and physical disability after disease-modulating therapy (DMT) start. METHODS: Using a group-modelling approach, we assessed trajectories of processing speed with oral Symbol Digit Modalities Test (SDMT) and physical disability with Expanded Disability Status Scale, from first DMT start among 1645 patients with RRMS followed during 2011-2022. We investigated predictors of trajectories using group membership as a multinomial outcome and calculated conditional probabilities linking membership across the trajectories. RESULTS: We identified 5 stable trajectories of processing speed: low SDMT scores (mean starting values=29.9; 5.4% of population), low/medium (44.3; 25.3%), medium (52.6; 37.9%), medium/high (63.1; 25.8%) and high (72.4; 5.6%). We identified 3 physical disability trajectories: no disability/stable (0.8; 26.8%), minimal disability/stable (1.6; 58.1%) and moderate disability (3.2; 15.1%), which increased to severe disability. Older patients starting interferons were more likely than younger patients starting rituximab to be on low processing speed trajectories. Older patients starting teriflunomide, with more than one comorbidity, and a history of pain treatment were more likely to belong to the moderate/severe physical disability trajectory, relative to the no disability one. There was a strong association between processing speed and physical disability trajectories. CONCLUSIONS: In this cohort of actively treated RRMS, patients' processing speed remained stable over the years following DMT start, whereas patients with moderate physical disability deteriorated in physical function. Nevertheless, there was a strong link between processing speed and disability after DMT start.

Haematopoietic stem cell transplantation for treatment of relapsing-remitting multiple sclerosis in Sweden: an observational cohort study.

BACKGROUND: A growing evidence base supports the use of autologous haematopoietic stem cell transplantation (aHSCT) for treatment of relapsing-remitting multiple sclerosis (RRMS), but it has not yet been integrated into most national clinical guidelines. The objective of this study was to assess efficacy and safety when aHSCT is implemented in routine healthcare. METHODS: We assessed 231 patients and the final analysis included 174 RRMS patients who were treated with aHSCT in Sweden before 1 January 2020. Efficacy was evaluated by performing a retrospective analysis of prospectively collected data from the Swedish MS registry. Procedure-related safety was assessed by analysing data from electronic patient records covering a period of 100 days following aHSCT. RESULTS: With a median follow-up time of 5.5 (IQR: 3.4-7.5) years, the Kaplan-Meier estimate for no evidence of disease activity was 73% (95% CI 66% to 81%) at 5 years and 65% (95% CI 57% to 75%) at 10 years. Out of the 149 patients with baseline disability, 80 (54%) improved, 55 (37%) were stable and 14 (9%) deteriorated. The mean number of adverse events per patient was 1.7 (±SD: 1.5) for grade 3 events and 0.06 (±SD: 0.3) for grade 4 events. Febrile neutropenia was the most common adverse event, affecting 68% of patients. There was no treatment-related mortality. CONCLUSIONS: Treatment with aHSCT for RRMS is associated with freedom from disease activity in a majority of patients, with acceptable adverse events. This procedure should be considered a standard of care for patients with highly active RRMS.

Dimethyl fumarate treatment in relapsing remitting MS changes the inflammatory CSF protein profile by a prominent decrease in T-helper 1 immunity.

BACKGROUND: Dimethyl fumarate (DMF) is a common treatment for multiple sclerosis (MS), but its mechanisms of action are not fully understood. Targeted proteomics offers insights into effects of DMF and biomarkers for treatment responses. OBJECTIVES: To assess influence of DMF on inflammation- and neuro-associated proteins in plasma and cerebrospinal fluid (CSF) in MS and to reveal biomarkers for predicting treatment responses. METHODS: Using the high-sensitivity and high-specificity method of proximity extension assay (PEA), we measured 182 inflammation- and neuro-associated proteins in paired plasma (n = 28) and CSF (n = 12) samples before and after one year of DMF treatment. Disease activity was evaluated through clinical examination and MRI. Statistical tests, network analysis, and regression models were used. RESULTS: Several proteins including T-helper 1 (Th1)-associated proteins (CXCL10, CXCL11, granzyme A, IL-12p70, lymphotoxin-alpha) were consistently decreased in CSF, while IL-7 was increased after one year of treatment. The changes in plasma protein levels did not follow the same pattern as in CSF. Logistic regression models identified potential biomarker candidates (including plexins and neurotrophins) for prediction of treatment response. CONCLUSIONS: DMF treatment induced prominent changes in CSF proteins, consistently reducing Th1-associated pro-inflammatory proteins. Neurodegeneration-related CSF proteins were able to predict treatment response. Protein biomarkers hold promise for personalized medicine.

Proteomics reveal biomarkers for diagnosis, disease activity and long-term disability outcomes in multiple sclerosis.

Sensitive and reliable protein biomarkers are needed to predict disease trajectory and personalize treatment strategies for multiple sclerosis (MS). Here, we use the highly sensitive proximity-extension assay combined with next-generation sequencing (Olink Explore) to quantify 1463 proteins in cerebrospinal fluid (CSF) and plasma from 143 people with early-stage MS and 43 healthy controls. With longitudinally followed discovery and replication cohorts, we identify CSF proteins that consistently predicted both short- and long-term disease progression. Lower levels of neurofilament light chain (NfL) in CSF is superior in predicting the absence of disease activity two years after sampling (replication AUC = 0.77) compared to all other tested proteins. Importantly, we also identify a combination of 11 CSF proteins (CXCL13, LTA, FCN2, ICAM3, LY9, SLAMF7, TYMP, CHI3L1, FYB1, TNFRSF1B and NfL) that predict the severity of disability worsening according to the normalized age-related MS severity score (replication AUC = 0.90). The identification of these proteins may help elucidate pathogenetic processes and might aid decisions on treatment strategies for persons with MS.

Prominent epigenetic and transcriptomic changes in CD4+ and CD8+ T cells during and after pregnancy in women with multiple sclerosis and controls.

BACKGROUND: Multiple sclerosis (MS) is a neuroinflammatory disease in which pregnancy leads to a temporary amelioration in disease activity as indicated by the profound decrease in relapses rate during the 3rd trimester of pregnancy. CD4+ and CD8+ T cells are implicated in MS pathogenesis as being key regulators of inflammation and brain lesion formation. Although Tcells are prime candidates for the pregnancy-associated improvement of MS, the precise mechanisms are yet unclear, and in particular, a deep characterization of the epigenetic and transcriptomic events that occur in peripheral T cells during pregnancy in MS is lacking. METHODS: Women with MS and healthy controls were longitudinally sampled before, during (1st, 2nd and 3rd trimesters) and after pregnancy. DNA methylation array and RNA sequencing were performed on paired CD4+ and CD8+ T cells samples. Differential analysis and network-based approaches were used to analyze the global dynamics of epigenetic and transcriptomic changes. RESULTS: Both DNA methylation and RNA sequencing revealed a prominent regulation, mostly peaking in the 3rd trimester and reversing post-partum, thus mirroring the clinical course with improvement followed by a worsening in disease activity. This rebound pattern was found to represent a general adaptation of the maternal immune system, with only minor differences between MS and controls. By using a network-based approach, we highlighted several genes at the core of this pregnancy-induced regulation, which were found to be enriched for genes and pathways previously reported to be involved in MS. Moreover, these pathways were enriched for in vitro stimulated genes and pregnancy hormones targets. CONCLUSION: This study represents, to our knowledge, the first in-depth investigation of the methylation and expression changes in peripheral CD4+ and CD8+ T cells during pregnancy in MS. Our findings indicate that pregnancy induces profound changes in peripheral T cells, in both MS and healthy controls, which are associated with the modulation of inflammation and MS activity.

Predictors of patient-reported fatigue symptom severity in a nationwide multiple sclerosis cohort.

BACKGROUND: Fatigue is a debilitating symptom of multiple sclerosis (MS), but its relation to sociodemographic and disease-related characteristics has not been investigated in larger studies. The objectives of this study were to evaluate predictors of self-reported fatigue in a Swedish nationwide register-based MS cohort. METHODS: Using a repeated cross-sectional design, we included 2,165 persons with relapsing- remitting and secondary progressive MS with one or multiple Fatigue Scale for Motor and Cognitive Functions (FSMC) scores, which was modelled using multivariable linear regressions for multiple predictors. RESULTS: Only associations to expanded disability status scale (EDSS) and Symbol Digit Modalities Test (SDMT) were considered clinically meaningful among MS-associated characteristics in our main model; compared to mild disability (EDSS 0-2.5), those with severe disability (EDSS ≥6) scored 17.6 (95% CI 13.1-22.2) FSMC points higher, while the difference was 10.7 (95% CI 8.0-13.4) points for the highest and lowest quartiles of SDMT. Differences between highest and lowest quartiles of health-related quality of life (HRQoL) instruments were even greater and considered clinically meaningful; EuroQoL Visual Analogue Scale (EQ-VAS) 31.9 (95% CI 29.9-33.8), Multiple Sclerosis Impact Scale (MSIS-29) psychological component 35.6 (95% CI 33.8-37.4) and MSIS-29 physical component 45.5 (95% CI 43.7-47.4). CONCLUSION: Higher self-reported fatigue is associated with higher disability level and worse cognitive processing speed, while associations to other MS-associated characteristics including MS type, line of disease modifying therapy (DMT), MS duration, relapse and new cerebral lesions are weak. Furthermore, we found a strong correlation between high fatigue rating and lower ratings on health-related quality of life instruments.

RNA-sequencing and mass-spectrometry proteomic time-series analysis of T-cell differentiation identified multiple splice variants models that predicted validated protein biomarkers in inflammatory diseases.

Profiling of mRNA expression is an important method to identify biomarkers but complicated by limited correlations between mRNA expression and protein abundance. We hypothesised that these correlations could be improved by mathematical models based on measuring splice variants and time delay in protein translation. We characterised time-series of primary human naïve CD4+ T cells during early T helper type 1 differentiation with RNA-sequencing and mass-spectrometry proteomics. We performed computational time-series analysis in this system and in two other key human and murine immune cell types. Linear mathematical mixed time delayed splice variant models were used to predict protein abundances, and the models were validated using out-of-sample predictions. Lastly, we re-analysed RNA-seq datasets to evaluate biomarker discovery in five T-cell associated diseases, further validating the findings for multiple sclerosis (MS) and asthma. The new models significantly out-performing models not including the usage of multiple splice variants and time delays, as shown in cross-validation tests. Our mathematical models provided more differentially expressed proteins between patients and controls in all five diseases. Moreover, analysis of these proteins in asthma and MS supported their relevance. One marker, sCD27, was validated in MS using two independent cohorts for evaluating response to treatment and disease prognosis. In summary, our splice variant and time delay models substantially improved the prediction of protein abundance from mRNA expression in three different immune cell types. The models provided valuable biomarker candidates, which were further validated in MS and asthma.

Plasma protein profiling reveals dynamic immunomodulatory changes in multiple sclerosis patients during pregnancy.

Multiple sclerosis (MS) is a chronic autoimmune neuroinflammatory and neurodegenerative disorder of the central nervous system. Pregnancy represents a natural modulation of the disease course, where the relapse rate decreases, especially in the 3rd trimester, followed by a transient exacerbation after delivery. Although the exact mechanisms behind the pregnancy-induced modulation are yet to be deciphered, it is likely that the immune tolerance established during pregnancy is involved. In this study, we used the highly sensitive and specific proximity extension assay technology to perform protein profiling analysis of 92 inflammation-related proteins in MS patients (n=15) and healthy controls (n=10), longitudinally sampled before, during, and after pregnancy. Differential expression analysis was performed using linear models and p-values were adjusted for false discovery rate due to multiple comparisons. Our findings reveal gradual dynamic changes in plasma proteins that are most prominent during the 3rd trimester while reverting post-partum. Thus, this pattern reflects the disease activity of MS during pregnancy. Among the differentially expressed proteins in pregnancy, several proteins with known immunoregulatory properties were upregulated, such as PD-L1, LIF-R, TGF-ß1, and CCL28. On the other hand, inflammatory chemokines such as CCL8, CCL13, and CXCL5, as well as members of the tumor necrosis factor family, TRANCE and TWEAK, were downregulated. Further in-depth studies will reveal if these proteins can serve as biomarkers in MS and whether they are mechanistically involved in the disease amelioration and worsening. A deeper understanding of the mechanisms involved may identify new treatment strategies mimicking the pregnancy milieu.

COVID-19 clinical outcomes and DMT of MS patients and population-based controls.

OBJECTIVE: To estimate risks for all-cause mortality and for severe COVID-19 in multiple sclerosis patients and across relapsing-remitting multiple sclerosis patients exposed to disease-modifying therapies. METHODS: We conducted a Swedish nationwide population-based multi-register linkage cohort study and followed all multiple sclerosis patients (n = 17,692 in March 2020), individually age-, sex-, and region-matched to five population-based controls (n = 86,176 in March 2020) during March 2020-June 2021. We compared annual all-cause mortality within and across cohorts, and assessed incidence rates and relative risks for hospitalization, intensive care admission, and death due to COVID-19 in relation to disease-modifying therapy use, using Cox regression. RESULTS: Absolute all-cause mortality among multiple sclerosis patients was higher from March to December 2020 than in previous years, but relative risks versus the population-based controls were similar to preceding years. Incidence rates of hospitalization, intensive care admission, and death due to COVID-19 remained in line with those for all-cause hospitalization, intensive care admission, and mortality. Among relapsing-remitting patients on rituximab, trends for differences in risk of hospitalization due to COVID-19 remained in the demographics-, socioeconomic status-, comorbidity-, and multiple sclerosis severity-adjusted model. INTERPRETATION: Risks of severe COVID-19-related outcomes were increased among multiple sclerosis patients as a whole compared to population controls, but risk increases were also seen for non-COVID-19 hospitalization, intensive care admission, and mortality, and did not significantly differ during the pandemic compared to pre-pandemic years. The risk conveyed by disease-modifying therapies was smaller than previously assumed, likely as a consequence of the possibility to better control for confounders.

Safety and efficacy of rituximab versus dimethyl fumarate in patients with relapsing-remitting multiple sclerosis or clinically isolated syndrome in Sweden: a rater-blinded, phase 3, randomised controlled trial.

BACKGROUND: B-cell depleting therapies are highly efficacious in relapsing-remitting multiple sclerosis but one such therapy, rituximab, is not approved for multiple sclerosis and no phase 3 trial data are available. We therefore examined the safety and efficacy of rituximab compared with dimethyl fumarate in patients with relapsing-remitting multiple sclerosis to obtain data that might allow inclusion of rituximab in treatment guidelines. METHODS: RIFUND-MS was a multicentre, rater-blinded, active-comparator, phase 3, randomised controlled trial done at 17 Swedish university and community hospitals. Key inclusion criteria for participants were: age 18-50 years; relapsing-remitting multiple sclerosis or clinically isolated syndrome according to prevailing McDonald criteria; 10 years or less since diagnosis; untreated or only exposed to interferons or glatiramer acetate; and with clinical or neuroradiological disease activity in the past year. Patients were automatically randomly assigned (1:1) by the treating physician using a randomisation module in the Swedish multiple sclerosis registry, without stratification, to oral dimethyl fumarate 240 mg twice daily or to intravenous rituximab 1000 mg followed by 500 mg every 6 months. Relapse evaluation, Expanded Disability Status Scale rating, and assessment of MRI scans were done by examining physicians and radiologists masked to treatment allocation. The primary outcome was the proportion of patients with at least one relapse (defined as subacute onset of new or worsening neurological symptoms compatible with multiple sclerosis with a duration of more than 24 h and preceded by at least 30 days of clinical stability), assessed in an intention-to-treat analysis using log-binomial regression with robust standard errors. This trial is registered at ClinicalTrials.gov, NCT02746744. FINDINGS: Between July 1, 2016, and Dec 18, 2018, 322 patients were screened for eligibility, 200 of whom were randomly assigned to a treatment group (100 assigned to rituximab and 100 assigned to dimethyl fumarate). The last patient completed 24-month follow-up on April 21, 2021. 98 patients in the rituximab group and 97 patients in the dimethyl fumarate group were eligible for the primary outcome analysis. Three (3%) patients in the rituximab group and 16 (16%) patients in the dimethyl fumarate group had a protocol-defined relapse during the trial, corresponding to a risk ratio of 0·19 (95% CI 0·06-0·62; p=0·0060). Infusion reactions (105 events [40·9 per 100 patient-years]) in the rituximab group and gastrointestinal reactions (65 events [47·4 per 100 patient-years]) and flush (65 events [47·4 per 100 patient-years]) in the dimethyl fumarate group were the most prevalent adverse events. There were no safety concerns. INTERPRETATION: RIFUND-MS provides evidence that rituximab given as 1000 mg followed by 500 mg every 6 months is superior to dimethyl fumarate in preventing relapses over 24 months in patients with early relapsing-remitting multiple sclerosis. Health economic and long-term safety studies of rituximab in patients with multiple sclerosis are needed. FUNDING: Swedish Research Council.

Non-Bacterial Thrombotic Endocarditis: A Presentation of COVID-19.

The SARS-CoV-2 virus is a newly emergent pathogen first identified in Wuhan, China, and responsible for the COVID-19 global pandemic. In this case report we describe a manifestation of non-bacterial thrombotic endocarditis with continuous peripheral embolization in a COVID-19-positive patient. The patient responded well to high-dose LMWH treatment with cessation of the embolic process. LEARNING POINTS: Raising awareness of possible complications of COVID-19.To highlight the importance of the careful consideration of and dosage of anticoagulation in non-bacterial thrombotic endocarditis.

Treatment effects of fingolimod in multiple sclerosis: Selective changes in peripheral blood lymphocyte subsets.

BACKGROUND: Treatment with fingolimod reduces inflammation in multiple sclerosis (MS) by inhibiting lymphocyte egress from lymph nodes. We aimed to map, in detail, the alterations in peripheral blood lymphocyte subpopulations in relation to clinical outcome in MS patients treated with fingolimod. METHODS: Paired blood samples from relapsing-remitting MS patients (n = 19) were collected before and after one year of treatment with fingolimod (0.5 mg/day). Absolute counts and relative proportions of a broad set of T- B- and NK-cell subsets were analyzed by flow cytometry. Blood samples from 18 healthy controls were used for baseline comparisons. RESULTS: Treatment with fingolimod markedly decreased the absolute numbers of all major lymphocyte subsets, except for NK cells. The reduction was most pronounced within the T helper (Th) and B cell populations (p<0.001). By phenotyping differentiation status of T cells, dramatic reductions within the naïve and central memory (CM) cell populations were found (p<0.001), while a less pronounced reduction was observed among effector memory (EM) cells (p<0.001). The numbers of regulatory T cells (Tregs) were also decreased (p<0.001), but to a lesser extent than other T cell populations, resulting in a relative preservation of Tregs with a memory phenotype (p = 0.002). CONCLUSIONS: Our results confirm that fingolimod therapy markedly reduces lymphocyte counts in peripheral blood of MS patients. Subgroup analysis of T cells showed that naïve and CM Th cells were the most profoundly affected and that memory Tregs were relatively preserved.

A validated gene regulatory network and GWAS identifies early regulators of T cell-associated diseases.

Early regulators of disease may increase understanding of disease mechanisms and serve as markers for presymptomatic diagnosis and treatment. However, early regulators are difficult to identify because patients generally present after they are symptomatic. We hypothesized that early regulators of T cell-associated diseases could be found by identifying upstream transcription factors (TFs) in T cell differentiation and by prioritizing hub TFs that were enriched for disease-associated polymorphisms. A gene regulatory network (GRN) was constructed by time series profiling of the transcriptomes and methylomes of human CD4(+) T cells during in vitro differentiation into four helper T cell lineages, in combination with sequence-based TF binding predictions. The TFs GATA3, MAF, and MYB were identified as early regulators and validated by ChIP-seq (chromatin immunoprecipitation sequencing) and small interfering RNA knockdowns. Differential mRNA expression of the TFs and their targets in T cell-associated diseases supports their clinical relevance. To directly test if the TFs were altered early in disease, T cells from patients with two T cell-mediated diseases, multiple sclerosis and seasonal allergic rhinitis, were analyzed. Strikingly, the TFs were differentially expressed during asymptomatic stages of both diseases, whereas their targets showed altered expression during symptomatic stages. This analytical strategy to identify early regulators of disease by combining GRNs with genome-wide association studies may be generally applicable for functional and clinical studies of early disease development.

Increased B cell and cytotoxic NK cell proportions and increased T cell responsiveness in blood of natalizumab-treated multiple sclerosis patients.

BACKGROUND: Changes in the blood lymphocyte composition probably both mediate and reflect the effects of natalizumab treatment in multiple sclerosis, with implications for treatment benefits and risks. METHODS: A broad panel of markers for lymphocyte populations, including states of activation and co-stimulation, as well as functional T cell responses to recall antigens and mitogens, were assessed by flow cytometry in 40 patients with relapsing multiple sclerosis before and after one-year natalizumab treatment. RESULTS: Absolute numbers of all major lymphocyte populations increased after treatment, most markedly for NK and B cells. The fraction of both memory and presumed regulatory B cell subsets increased, as did CD3(-)CD56(dim) cytotoxic NK cells, whereas CD3(-)CD56(bright) regulatory NK cells decreased. The increase in cell numbers was further associated with a restored T cell responsiveness to recall antigens and mitogens in functional assays. CONCLUSIONS: Our data confirms that natalizumab treatment increases the number of lymphocytes in blood, likely mirroring the expression of VLA-4 being highest on NK and B cells. This finding supports reduction of lymphocyte extravasation as a main mode of action, although the differential effects on subpopulation composition suggests that cell-signalling may also be affected. The systemic increase in T cell responsiveness reflects the increase in numbers, and while augmenting anti-infectious responses systemically, localized responses may become correspondingly decreased.

Association between change in normal appearing white matter metabolites and intrathecal inflammation in natalizumab-treated multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) is associated not only with focal inflammatory lesions but also diffuse pathology in the central nervous system (CNS). Since there is no firm association between the amount of focal inflammatory lesions and disease severity, diffuse pathology in normal appearing white matter (NAWM) may be crucial for disease progression. Immunomodulating treatments for MS reduce the number of focal lesions, but possible effects on diffuse white matter pathology are less studied. Furthermore, it is not known whether intrathecal levels of inflammatory or neurodegenerative markers are associated with development of pathology in NAWM. METHODS: Quantitative proton magnetic resonance spectroscopy ((1)H-MRS) was used to investigate NAWM in 27 patients with relapsing MS before and after one year of treatment with natalizumab as well as NAWM in 20 healthy controls at baseline. Changes in (1)H-MRS metabolite concentrations during treatment were also correlated with a panel of intrathecal markers of inflammation and neurodegeneration in 24 of these 27 patients. RESULTS: The group levels of (1)H-MRS metabolite concentrations were unchanged pre- to posttreatment, but a pattern of high magnitude correlation coefficients (r = 0.43-0.67, p<0.0005-0.03) were found between changes in individual metabolite concentrations (total creatine and total choline) and levels of pro-inflammatory markers (IL-1ß and CXCL8). CONCLUSIONS: Despite a clinical improvement and a global decrease in levels of inflammatory markers in cerebrospinal fluid during treatment, high levels of pro-inflammatory CXCL8 and IL-1ß were associated with an increase in (1)H-MRS metabolites indicative of continued gliosis development and membrane turnover in NAWM.

Short- and long-term effects of T-cell modulating agents in experimental autoimmunity.

Due to the easy and reliable induction of a disease condition with many of the features present in human autoimmunity, mercury-induced autoimmunity (mHgAI) in rodents is a favourable autoimmune model. Genetically susceptible (H-2(s)) mice develop in response to mercury (Hg) a systemic autoimmune condition with antinucleolar antibodies (ANoA) targeting the protein fibrillarin, transient polyclonal B-cell activation, hyperimmunoglobulinemia, and systemic immune-complex (IC) deposits. In order to study the short- and long-term effects of treatment with immunomodulating agents on the disease parameters in HgAI, groups of B10.S (H-2(s)) mice were given 6 mg HgCl(2)/l drinking water for 22 weeks. Three weeks initial treatment with cyclosporin A (CyA), a high dose of tacrolimus (HD tacrolimus), or anti-CD4 monoclonal antibody (a-CD4) inhibited induction of ANoA and IC deposit by Hg. This effect persisted for the subsequent 19 weeks when the mice were only treated with Hg. Initial treatment with anti-IL-4 monoclonal antibody (a-IL-4) for 3 weeks inhibited induction of IgE and IC deposits by Hg, but not ANoA. However, subsequent treatment with Hg without a-IL-4 for 19 weeks induced IC deposits. The T-cell modulating agents aggravated some of the HgAI disease parameters: a-CD4 stimulated the polyclonal B-cell activation, a-IL-4 increased the IgG antichromatin antibody response, and a low dose of tacrolimus (LD tacrolimus) enhanced the ANoA, the polyclonal B-cell activation, and the IC deposits. We conclude that a short initial treatment with a-CD4 or CyA efficiently protects against induction of systemic autoimmunity for an extended period of time. However, some of the T-cell modulating agents, especially a low dose of tacrolimus, aggravate autoimmune manifestations not only during ongoing treatment, but also after treatment with these agents has ceased.