Maternal obesity increases the risk of hepatocellular carcinoma through the transmission of an altered gut microbiome

Background & Aims

Emerging evidence suggests that maternal obesity negatively impacts the health of offspring. Additionally, obesity is a risk factor for hepatocellular carcinoma (HCC). Our study aims to investigate the impact of maternal obesity on the risk for HCC development in offspring and elucidate the underlying transmission mechanisms.

Methods

Female mice were fed either a high-fat diet (HFD) or a normal diet (ND). All offspring received a ND after weaning. We studied liver histology and tumor load in a N-diethylnitrosamine (DEN)-induced HCC mouse model.

Results

Maternal obesity induced a distinguishable shift in gut microbial composition. At 40 weeks, female offspring of HFD-fed mothers (HFD offspring) were more likely to develop steatosis (9.43% vs. 3.09%, p = 0.0023) and fibrosis (3.75% vs. 2.70%, p = 0.039), as well as exhibiting an increased number of inflammatory infiltrates (4.8 vs. 1.0, p = 0.018) and higher expression of genes involved in fibrosis and inflammation, compared to offspring of ND-fed mothers (ND offspring). A higher proportion of HFD offspring developed liver tumors after DEN induction (79.8% vs. 37.5%, p = 0.0084) with a higher mean tumor volume (234 vs. 3 μm3, p = 0.0041). HFD offspring had a significantly less diverse microbiota than ND offspring (Shannon index 2.56 vs. 2.92, p = 0.0089), which was rescued through co-housing. In the principal component analysis, the microbiota profile of co-housed animals clustered together, regardless of maternal diet. Co-housing of HFD offspring with ND offspring normalized their tumor load.

Conclusions

Maternal obesity increases female offspring's susceptibility to HCC. The transmission of an altered gut microbiome plays an important role in this predisposition.

Impact and implications

The worldwide incidence of obesity is constantly rising, with more and more children born to obese mothers. In this study, we investigate the impact of maternal diet on gut microbiome composition and its role in liver cancer development in offspring. We found that mice born to mothers with a high-fat diet inherited a less diverse gut microbiome, presented chronic liver injury and an increased risk of developing liver cancer. Co-housing offspring from normal diet- and high-fat diet-fed mothers restored the gut microbiome and, remarkably, normalized the risk of developing liver cancer. The implementation of microbial screening and restoration of microbial diversity holds promise in helping to identify and treat individuals at risk to prevent harm for future generations.

Global epidemiology of rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease that predominantly affects the joints. The prevalence of RA varies globally, with generally a higher prevalence in industrialized countries, which may be explained by exposures to environmental risk factors, but also by genetic factors, differing demographics and under-reporting in other parts of the world. Over the past three decades, strong trends of the declining severity of RA probably reflect changes in treatment paradigms and overall better management of the disease. Other trends include increasing RA prevalence. Common risk factors for RA include both modifiable lifestyle-associated variables and non-modifiable features, such as genetics and sex. A better understanding of the natural history of RA, and of the factors that contribute to the development of RA in specific populations, might lead to the introduction of specific prevention strategies for this debilitating disease.

POS0422 A HISTORY OF CHLAMYDIAE INFECTION IN RHEUMATOID ARTHRITIS DEVELOPMENT

Background

Current hypotheses for the ethiopathogenesis of rheumatoid arthritis (RA) postulate an infectious agent initiating autoimmunity, which is thought to be at the mucosal level. Chlamydiae infections have been previously associated to development of an acute inflammatory arthritis, which can become chronic in some patients. Chlamydia trachomatis was detected in synovial fluid and tissue of RA patients, at least in early disease, suggesting that this organism could be involved in initiating RA onset, at least in a subset of patients.

Objectives

To investigate the association between Chlamydiae infection and the development of autoimmunity and pre-clinical manifestations associated with RA.

Methods

This study was performed in an ongoing prospective study of individuals genetically at risk of developing RA, namely first-degree relatives of RA patients (RA-FDR). Individuals without clinical evidence of RA are enrolled, and assessed yearly, clinically and biologically. We included all RA-FDRs who responded to a Chlamydiae infection questionnaire, and the exposure of interest was self-reported Chlamydiae infection. The primary outcome was autoimmunity associated with RA (seropositivity) defined by the presence of anti-citrullinated peptide antibodies (ACPA) and/or rheumatoid factors (RF) at the last visit. Seropositive inflammatory arthritis at the last visit was a secondary outcome. We used logistic regression to analyze univariable and multivariable associations, adjusting for age and gender as potential confounders.

Results

A total of 1254 RA-FDRs were analyzed, of which 168 (13.4%) had developed seropositivity. The prevalence of self-reported Chlamydia infection was significantly higher in seropositive individuals as compared to controls (17.9% versus 9.8%, P<0.01) (Table 1). A significant association between the self-reported history of Chlamydiae infection and the seropositivity was observed in both univariate and multivariate analyses (OR=2.00, 95% CI: 1.27-3.09; OR=1.91, 95% CI: 1.20-2.95, respectively). A sub-group of 48 RA-FDRs (4 %) presented inflammatory arthritis in conjunction with seropositivity. This subgroup, considered at highest risk for RA, reported significantly more often prior infections with Chlamydiae than the negative subgroup (20.8% versus 10.5%, P<0.05). The ORs for the association of self-reported history of Chlamydiae infection and inflammatory arthritis coupled to RA-associated autoimmunity were 2.23 (95% CI: 1.03-4.43, P<0.01, univariate analysis) and 1.91 (95% CI: 0.88-3.82, P=0.08, multivariate analysis).

Table 1.

A potential association between a self-reported history of Chlamydiae infection and RA development

RA-FDR with a self-reported chlamydia infection anamnesis (n=1254)Study GroupsSelf-reported “infection”Univariate analysisMultivariate analysis1OR (95% CI)OR (95% CI)Seropositive RA-FDR (n=168)30 (17.9%)2.00** (1.27 - 3.09)1.91** (1.20 – 2.95)Seronegative RA-FDR (n=1063)104 (9.8%)RA-FDR with seropositive inflammatory arthritis2 (n=48)10 (20.8%)2.23* (1.03 – 4.43)1.91 (0.88 – 3.82)RA-FDR without seropositive inflammatory arthritis (n = 1206)127 (10.5%)

1Logistic regression model adjusting for age and gender.

2Seropositive inflammatory arthritis was defined by being either: seropositive RA; seropositive “arthritis” (defined by at least one swollen joint at physical examination); seropositive with MSUS (musculoskeletal ultrasound) inflammatory activity.

* P-value < 0.05

** P-value < 0.01

Conclusion

Our results suggest that a history of Chlamydiae infection may be a risk factor for the development of RA in a subset of individuals at genetic risk for the disease. Serological analyses to assess the prevalence of antibodies to C. trachomatis major outer membrane protein (MOMP) are under way to confirm these preliminary data.

References

[1]Arleevskaya MI et al. Front Microbiol. 2016;7:1296;

[2]Inman RD et al. Curr Opin Rheumatol. 2000;12(4):254-262;

[3]Swanborg RH et al. Expert Rev Mol Med. 2006;8(29):1-23;

[4]Villareal C et al. Arthritis Res. 2002;4(1):5-9.

Disclosure of Interests

Céline Lamacchia: None declared, Romain Aymon: None declared, Benoit GILBERT: None declared, Olivia Studer: None declared, Kim Lauper Consultant of: KL reports consultant fees for Pfizer and speaker fees for Pfizer, Viatris and Celltrion, outside of the submitted work, Axel Finckh: None declared.

AB0018 SERUM ANTIBODIES AGAINST ORAL AND INTESTINAL BACTERIA IN INDIVIDUALS AT RISK FOR RHEUMATOID ARTHRITIS, CHRONIC RA PATIENTS, AND NEW ONSET PATIENTS WITH DIFFERENT RHEUMATIC DISEASES

Background

Evidence about the influence of microbes in autoimmune diseases such as rheumatoid arthritis (RA) has grown in recent years. However, the precise role of specific bacteria remains largely unknown. Previous investigations identified several oral pathobionts to be specifically targeted by serum antibodies in RA patients.1 In addition, Pianta et al.2 identified recognition of Prevotella copri by the immune system of RA patients. It has to be noted, however, that such findings have neither been reproduced, nor studied in different disease stages. Also, the assumptions made for P. copri relied on a single strain, the type strain DSM18205, isolated from a healthy individual.3 However, there is recent evidence suggesting P. copri to be a non-monotypic species, meaning it clusters into several subspecies displaying geno- and phenotypic differences4.

Objectives

This study aimed to quantify serum antibodies targeting different P. copri strains, as well as known oral pathobionts in patients with different rheumatic diseases or in various stages of RA development.

Methods

We used custom-made ELISA assays measuring pathogen-specific IgG levels in patient’s serum. Samples were tested against P. copri strains isolated from stool samples of healthy donors and RA patients, as well as the following oral pathobionts: Porphyromonas gingivalis, Prevotella intermedia and Prevotella melaninogenica. We analyzed 120 samples from a Swiss cohort of first-degree relatives, individuals in various pre-clinical RA stages (SCREEN-RA), and 45 samples of patients with established RA (SCQM cohort). These participants were categorized as asymptomatic seronegative individuals (FDR), individuals with ‘systemic autoimmunity associated with RA’ (ACPA and/or RF autoantibodies) (preRA 1), individuals with ’clinically suspect arthralgia’ or ‘undifferentiated arthritis’ with/without autoantibodies (preRA 2) and chronic RA patients (cRA). Additionally, we included 92 serum samples from new-onset patients diagnosed with RA, psoriatic arthritis (PsA) axial spondyloarthritis (SpA), or other non-rheumatic diseases (NRD) recruited via the german RheumaVOR cohort (Table 1).

Table 1.

Overview human cohort studies

cohortSCREEN-RASCQMRheumaVORpatient groupFDRpreRA 1preRA 2cRANRDRAPsAaxSpAtotal numbers4240384532143016age median5454595643.551.550.533sex (F/M)32/1035/534/435/1019/139/515/1510/6ACPA positivity0259310700RF positivity0198340700

Results

Overall, there were no significant differences in the IgG reactivity profiles between the patient groups against the distinct P. copri strains or oral pathobionts (Figure 1). However, performing this assay with P. copri strains from distinct subspecies identified clear differences and revealed important variability in the IgG reactivity.

Figure 1.

Serum IgG responses against different microbes from individuals recruited via SCREEN-RA, SCQM or RheumaVOR cohort

Conclusion

Our study failed to reproduce previous results and could confirm neither P. copri nor the three oral pathobionts to be particularly targeted by systemic IgG immune reactions in RA patients. However, we identified strain-specific differences in the IgG reactivity against P. copri, regardless of disease type or state. The latter suggests that the overall immunostimulatory potential of P. copri might be dependent on its strain/subspecies level. Our findings underline the necessity of P. copri strain-level characterization when studying host-microbiota immune interactions.

References

[1]Ogrendik et al. MedGenMed (2005)

[2]Pianta et al. Arthritis Rheumatol. (2017)

[3]Hayashi et al. Int. J. Syst. Evol. Microbiol. (2007)

[4]Tett et al. Cell Host & Microbe (2019)

Disclosure of Interests

None declared

POS1420 DOUBLY ROBUST ESTIMATOR FOR AVERAGE TREATMENT EFFECT AS SENSITIVITY ANALYSIS FOR COMPARATIVE EFFECTIVENESS RESEARCH. AN EXAMPLE COMPARING DRUG MAINTENANCE BETWEEN BARICITINIB AND ALTERNATIVE BIOLOGIC DMARDS

Background

Drug maintenance is a common outcome measure of real world effectiveness studies, because it combines a measure of drug effectiveness and its tolerance / safety. Major hurdles of observational studies are potential selection biases and confounding. Cox proportional hazard ratio models address this issue by adjusting for potential confounders, but misspecification of the model may lead to biased estimates. ‘Augmented Inverse Probability Treatment Weighting’ (AIPTW) has the attractive property of being doubly robust, meaning that only one of the two underlying models has to be correctly specified to obtain consistent estimates. It can be used as a sensitivity analysis for Cox models, when analyzing time-to-event data.

Objectives

To evaluate AIPTW estimator and test the robustness of the results obtained by a Cox model.

Methods

Previous analyses in the Swiss rheumatoid arthritis (RA) registry (SCQM) had demonstrated that time to all-cause-discontinuation was significantly longer in RA patients on bariticinib (BARI, N = 273) compared to TNF-inhibitors (TNFi, N = 473); but not compared to other mode of actions biologics (OMA, N = 378) [1], in an adjusted Cox regression including age, gender, BMI, concomitant csDMARD, prednisone, CDAI score, disease duration, smoking status, line of therapy and seropositivity.

Here we repeat the same analysis using AIPTW, including the same potential confounders. We combine a propensity score using a logistic regression model and an inverse probability weighted Cox regression. Two implementations of the AIPTW estimator are considered. First we use the RiskRegression package in R, to obtain risk ratios. Then we implement the AIPTW manually to obtain the average treatment effect as the difference in median survival time.

Results

Time to treatment discontinuation measured with Cox model was significantly longer for RA patients on BARI compared to patients on TNFi according to the adjusted Cox model (HR = 1.79), and a similar non-significant trend existed when compared to OMA (HR = 1.29).

When considering 90-day treatment discontinuation measured with the AIPTW, the results were qualitatively very similar: the risk ratio between BARI and TNFi groups is statistically significant (RR = 2.51), while that of BARI against OMA is larger than one (RR = 1.47), but not statistically significant. Confidence intervals are larger with the AIPTW estimation.

Table 1.

Cox Regression HR and AIPTW risk ratios

Cox Regression Hazard Ratio (95% CI)AIPTW Estimate of 90-day risk ratio of treatment discontinuation (95% CI)BARI vs. TNFi1.79* (1.34-2.38)2.51* (1.19 – 3.83)BARI vs. OMA1.29 (0.96-1.73)1.47 (0.76 – 2.18)

Legend: BARI: baricitinib; TNFi: TNF-inhibitors; OMA: Other Mode of Actions biologics; AIPTW: Augmented Inverse Probability Treatment Weighting. 95% CI: 95% Confidence Interval. *: statistically significant result at the p<0.05 level.

Figure 1.

Absolute risk of treatment discontinuation over time between patients on baricitinib and patients on TNF inhibitors, estimated with AIPTW.

Conclusion

Time to treatment discontinuation measured with Cox model was significantly longer for RA patients on BARI compared to patients on TNFi according to the adjusted Cox model (HR = 1.79), and a similar non-significant trend existed when compared to OMA (HR = 1.29).

When considering 90-day treatment discontinuation measured with the AIPTW, the results were qualitatively very similar: the risk ratio between BARI and TNFi groups is statistically significant (RR = 2.51), while that of BARI against OMA is larger than one (RR = 1.47), but not statistically significant. Confidence intervals are larger with the AIPTW estimation.

Conflict of Interest:

This analysis has been made possible by financial support of Eli Lilly (Suisse) SA to the Geneva University Hospitals (HUG).

References

[1]Ann Rheum Dis, supplement 1, year 2021. DOI: 10.1136/annrheumdis-2021-eular.1781

Disclosure of Interests

Romain Aymon: None declared, Benoit GILBERT: None declared, Denis Mongin: None declared, Eric Nham: None declared, Cedric Laedermann Employee of: Eli Lilly, Rüdiger Müller Consultant of: Streuli Pharma, Gebro Pharma, AbbVie, Kim Lauper Speakers bureau: Pfizer, Viatris and Celltrion, Consultant of: Pfizer, Delphine Courvoisier: None declared, Axel Finckh: None declared

POS0435 IMPACT OF COMBINATION THERAPY WITH csDMARDs ON THE EFFECTIVENESS OF BIOLOGIC OR TARGETED SYNTHETIC DMARDs IN A REAL-LIFE SETTING: RESULTS FROM THE SWISS RHEUMATOID ARTHRITIS REGISTER (SCQM-RA)

Background

Management guidelines of RA suggest to administer biological or targeted synthetic DMARD (b/tsDMARD) in combination with conventional synthetic DMARD (csDMARD). Limited data exists about the impact of such csDMARD combination therapy (co-therapy) in real life settings, in particular for baricitinib use compared to other types of b/tsDMARD.

Objectives

To assess the impact of concomitant csDMARD prescription on b/tsDMARD maintenance, in a real-world setting.

Methods

This is a nested cohort study within the Swiss registry of RA patients (Swiss Clinical Quality Management (SCQM-RA)), of treatment courses with bDMARDs or baricitinib (BARI) initiated between 2017-09-01 and 2020-06-01, with at least one follow-up visit. We compared the time-to-drug-discontinuation (drug maintenance), as a measure of drug effectiveness of b/tsDMARDs, with or without csDMARD co-therapy. Our exposure of interest was the impact of csDMARD co-therapy compared to monotherapy in 3 categories of b/tsDMARDs: baricitinib (BARI), TNFi inhibitors (TNFi) and other modes of action bDMARDs (OMA). Co-therapy was defined as receiving at least one csDMARD during at least 40% of the b/tsDMARD treatment courses (TC) duration.

Baseline characteristics were compared using t-tests or χ2. Survival Kaplan-Meier curves, with Log-rank test, were used to assess time-to-discontinuation. Cox models were applied to obtain adjusted hazard ratios (HR) using age, BMI, corticosteroid treatment, CDAI score, disease duration, smoking, line of therapy, seropositivity, gender as covariates. Missing baseline CDAI values were imputed using linear model with quadratic regression time.

Results

1065 TC were included (273 BARI, 319 OMA, 473 TNFi), about half of which were initiated with csDMARD co-therapy (Table 1). In the co-therapy groups, csDMARD were taken on average 98% of the TC duration. Methotrexate was the most prescribed csDMARD (Table 1).

Table 1.

Baseline characteristics of studied population

VariableBARIOMATNFiBARIBARI + csDMARDp valuesOMAOMA + csDMARDp valuesTNFiTNFi + csDMARDp valuesn = 164n = 109n = 170n = 149n = 183n = 290Mean (SD)Mean (SD)Mean (SD)Otherwise: %*Otherwise: %*Otherwise: %*Prednisone21 %24 %0.7322 %29 %0.1820 %20 %1.00Line of Therapy- 1st (= bio-naive)17 %18 %0.0419 %22 %0.5142 %51 %0.15-2nd17 %24 %24 %22 %26 %20 %-3rd24 %11 %27 %20 %14 %10 %-4th or later42 %48 %31 %36 %19 %18 %Female82 %73 %0.1475 %71 %0.4281 %70 %0.01Age60 (15)57 (11)0.0560 (13)57 (12)0.0352 (16)53 (14)0.66Disease duration (years)13 (10)12 (9)0.8211 (9)11 (10)0.589 (10)8 (8)0.36CDAI baseline19 (10)18 (8)0.5320 (14)21 (12)0.5318 (10)18 (11)0.64Seropositivity77 %72 %0.3574 %75 %0.9668 %71 %0.64csDMARD type- MTX-48 %--50 %--60 %-- MTX + other-2 %-5 %-4 %-- Other-50 %-45 %-36 %-

TC = treatment course, BARI = baricitinib, TNFi = TNF inhibitors, OMA = Other Mode of Action drugs, DMARDs = Disease Modifying Anti-Rheumatic Drugs, csDMARDs = classical synthetic DMARDs, SD = standard deviation. CDAI = Clinical Disease Activity Index. csDMARD = conventional synthetic DMARD. MTX = Methotrexate. Other: Other csDMARD. * Percentages relate to total n treatment courses. p values in bold highlight statistically significant difference between respective groups. All % mean and SD values are rounded to integers.

Even after adjustment, we found no difference in drug maintenance with and without concomitant csDMARD in the BARI group (crude p = 0.67; HR co-therapy 2.17, 95% CI [0.61;7.77], p = 0.16) and in the TNFi group (crude p = 0.13; HR co-therapy 1.24, 95% CI [0.56;2.74], p = 0.60). Adjusted drug maintenance with or without csDMARD was also similar in the OMA group, despite non-adjusted p-value in favor of monotherapy (Figure 1) (crude p = 0.007; HR co-therapy 0.66, 95% CI [0.25;1.80], p = 0.39).

Figure 1.

Drug maintenance of monotherapy vs csDMARD co-therapy (Non-adjusted Kaplan-Meier).

Conclusion

Our data suggest that drug maintenance of BARI, OMA and TNFi, were not significantly modified by concomitant csDMARD therapy.

Disclosure of Interests

Benoit GILBERT Speakers bureau: Once for Lilly, outside of the presented work., Denis Mongin: None declared, Eric Nham: None declared, Delphine Courvoisier: None declared, Kim Lauper Speakers bureau: for Pfizer, Viatris and Celltrion, outside of the submitted work., Consultant of: for Pfizer, outside of the submitted work., Cedric Laedermann Employee of: Currently employed by Eli Lilly., Rüdiger Müller: None declared, Axel Finckh Speakers bureau: Lilly, Grant/research support from: Research Grant by Lilly, to the rheumatology division.

POS0668 REAL WORLD EFFECTIVENESS OF BARICITINIB IN THE SWISS RHEUMATOID ARTHRITIS REGISTER (SCQM-RA)

Background:

When not responding to conventional synthetic DMARDs (csDMARDs), rheumatoid arthritis (RA) patients may receive biological DMARDs (bDMARDs) or targeted synthetic DMARDs (tsDMARDs) including baricitinib (BARI). While BARI has demonstrated efficacy in randomized controlled trials, limited studies have established comparative effectiveness in real world settings, in particular when used in b/tsDMARD-naïve patients.

Objectives:

To analyze the effectiveness of BARI versus alternative bDMARDs, as assessed by drug maintenance over time and by response rates at 12 months.

Methods:

This is a nested study of RA patients, within the prospective Swiss Clinical Quality Management (SCQM) observational cohort.

All treatment courses (TC) with BARI or alternative bDMARDs initiated between 2017-09-01 and 2020-06-01, with at least one follow-up visit, were included. TC with BARI were compared to TC with alternative bDMARDs (non-BARI), including all b/tsDMARDs except rituximab. The non-BARI group was then subdivided into TNF inhibitors (TNFi) and other mode of action bDMARDs (OMA), excluding tsDMARDs. A secondary analysis focusing specifically on b/tsDMARD naïve patients was conducted.

Baseline characteristics were compared using ANOVA or χ2 tests. A Cox-model survival analysis assessed drug maintenance. 12-month response rates were estimated using an attrition-corrected, confounder-adjusted approach (1). CDAI score ≤10 defined low disease activity state (LDA), and CDAI score ≤2.8 defined remission.

Results:

Overall, 1218 eligible TC (from 1028 patients) were initiated during the study period (273 in BARI, 154 other tsDMARD, 473 in TNFi and 318 in OMA). Drug maintenance was significantly shorter for TNFi compared to BARI, even after adjustment for potential confounders (Hazard ratio (HR) for drug discontinuation 1.85 (95% CI [1,40 – 2,43]); p < 0.001). Drug maintenance was also numerically shorter for the OMA group compared to BARI, but the difference was not significant (HR 1.18 (95% CI [0.87 – 1.60]); p = 0.28). These differences were larger when analysing only bDMARD-naïve patients (Figure 1a).

All TC taken together, the rates of LDA and remission did not differ significantly between the 3 groups at 12 months. LDA ranged from 63% to 67% (BARI vs OMA p = 0.87; BARI vs TNFi p = 0.81) and remission from 19% to 23% (BARI vs OMA p = 0.30; BARI vs TNFi p = 0.77; Figure 1b).

Conclusion:

BARI demonstrated a significantly higher overall drug maintenance than TNFi, and a similar drug maintenance to OMA, both in a bDMARD-naïve population and in the overall population. The adjusted 12-month response rates did not differ between BARI, TNFi and OMA groups. These results suggest that prescription of BARI after csDMARD has at least similar outcomes as alternative bDMARDs.

References:

[1]Lauper, K., et al. Sat0588. Annals of the Rheumatic Diseases 78 (2019).

Table 1.

Baseline characteristics of studied population

VariableOverall comparison:BARI vs non-BARISubgroup analysis 1:by bDMARD type (tsDMARD excluded)Subgroup analysis 2:In b/tsDMARD-naïve patientsBARI(TC = 273; 273 patients)Non-BARI(altogether)(TC = 945; 755 patients)p valuesTNFi(TC = 473; 408 patients)OMA(TC = 318; 298 patients)p values(vs BARI)BARI(n = 46)TNFi(n = 225)OMA(n = 65)p valuesMean (SD)Otherwise: n %Mean (SD)Otherwise: n %Mean (SD)Otherwise: n %Concomitant csDMARD41 %46 %0.1754 %41 %<0.0150 %61 %48 %0.1Line of Therapy-1st (= bio-naive)17 %35 %<0.0148 %20 %<0.01100 %100 %100 %-2nd20 %23 %23 %23 %-3rd19 %16 %11 %24 %-4th or later44 %26 %18 %33 %Female78%74 %<0.2174 %73 %0.2870 %71 %74 %0.88Age59 (14)56 (14)0.0152 (15)58 (13)<0.0157 (15)51 (14)57 (16)<0.01Disease duration (years)13 (10)10 (9)<0.018 (9)11 (9)<0.015.5 (6.45)5 (7)6.5 (9)0.243CDAI baseline15 (9)15 (10)0.914 (9)16 (11)0.0513 (7)14 (9)14 (10)0.72Previous tsDMARD (non-BARI)33 %8 %<0.014 %11 %<0.010 %0 %0 %TC duration > 12-months37 %29 %0.0127 %30 %0.0237 %29 %34 %0.52

BARI = baricitinib, TNFi = TNF inhibitors, OMA = other mode of action, Non-BARI = TNFi + OMA + other tsDMARDs, SD = standard deviation.

Disclosure of Interests:

Benoit GILBERT: None declared, Delphine Courvoisier: None declared, Denis Mongin: None declared, Kim Lauper Consultant of: Gilead Galapagos, Grant/research support from: AbbVie, Clementine Perrier Shareholder of: Eli Lilly, Employee of: Eli Lilly, Rudiger Muller Consultant of: AbbVie, Novartis, Grant/research support from: GEBRO Pharma, Axel Finckh Speakers bureau: AbbVie, BMS, Pfizer, Eli-Lilly, Consultant of: AbbVie, BMS, Pfizer, Eli-Lilly, Grant/research support from: BMS, Pfizer, Eli-Lilly

POS1168 SELF-REPORTED SARS-CoV2 TESTING AND COVID-19 DISEASE IN PATIENTS WITH RHEUMATOID ARTHRITIS, AXIAL SPONDYLOARTHRITIS AND PSORIATIC ARTHRITIS IN A SWISS OBSERVATIONAL COHORT

Background:

Since the beginning of the pandemic in Switzerland, immunosuppressed people were strongly advised to be tested for SARS-CoV2 when symptomatic as it was conjectured that they might be more at risk for infection and/or severe disease. While patients with autoimmune diseases might be indeed more at risk of death from COVID-191, it remains unknown, whether there are differences in infection or complication rates between patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA), and whether this relates to their disease or their treatment. Additionally, the prevalence of SARS-CoV2 testing in this population is not known.

Objectives:

This study aimed to assess and compare the rate of COVID-19 and SARS-CoV2 testing in patients with RA, AxSpA and PsA, the potential association with their treatment and, for testing, the number of symptoms.

Methods:

We included patients with RA, AxSpA and PsA from the Swiss Clinical Quality Management register (SCQM) using a smartphone app (mySCQM) to record information between March and December 2020. The outcomes of interest were self-reported SARS-CoV2 testing, symptoms compatible with COVID-19 during the previous month and confirmed COVID-19 through PCR nasopharyngeal swab. Outcomes were evaluated over the complete length of the aforementioned period (i.e. the outcome has been reported at least once during the period). Outcomes were compared between diseases groups, using logistic regression. We also evaluated the association of baseline treatment (TNF-inhibitors, b/tsDMARDs with other modes of action (OMA), no b/tsDMARDs) on the odds of symptoms and testing and the association of the number of symptoms (0-9) on the odds of testing. The analyses of SARS-CoV2 testing and COVID-19 symptoms were additionally adjusted for age, gender, glucocorticoids and csDMARDs. Confirmed cases were not adjusted for treatment and other covariates considering the low number of events.

Results:

We included 927 patients with RA, 805 with AxSpa and 453 with PsA (Table 1). 1010 patients reported COVID-19-like symptoms (mostly fever, runny nose and cough), but only 455 of them (45%) reported being tested. 151 patients were tested without symptoms. In between March and December 2020, 7.6% of RA, 8.5% of AxSpA and 10.5% of PsA patients were tested positive for COVID-19 (p=0.678). The odds of testing, symptoms and confirmed COVID-19 were similar between diseases and not associated with treatment for testing and symptoms (Figure 1). The number of symptoms was associated with the odds of testing (OR 1.43, 95%CI 1.37-1.50 by symptom).

Table 1.RAaxSpAPsApn 927 805 453Age (mean, SD)56.4 (13)47.1 (12)52.7 (11)<0.001Genderfemale 705 (76) 403 (50) 230 (51)<0.001TreatmentTNFi 272 (29) 498 (62) 174 (38)<0.001OMA 355 (38) 71 (9) 137 (30)No b/tsDMARDs 300 (32) 236 (29) 142 (31)csDMARDs use 476 (51) 111 (14) 147 (33)<0.001Steroids use 93 (10) 11 (1) 19 (4)<0.001Disease duration14.2 (10)17.4 (11)14.8 (12)<0.001Testing for COVID-19All patients258 (28)231 (29)117 (26) 0.550Patients with symptoms189/427 (44)179/392 (46)87/191 (46) 0.911Presence of COVID-19 symptoms427 (46)392 (49)191 (42) 0.082Positive COVID-19 test* 18/237 (8) 19/223 (9) 11/105 (11) 0.678

N, % when not specified otherwise. *Missing data on test results in 41 patients χ2 test for categorical and t-test for continuous variables.

Figure 1.

Conclusion:

Prevalence of COVID-19 symptoms and confirmed cases was similar between diseases, and for symptoms, was not associated with treatment. Despite strong advice from health authorities, less than 50% of patients with inflammatory rheumatic diseases and COVID-19 symptoms were tested. This proportion was not significantly different between diseases and not influenced by type of treatment. Efforts should be made to improve rates of SARS-CoV2 testing in patients with rheumatic diseases.

References:

[1]Williamson, E. J. et al. Factors associated with COVID-19-related death using OpenSAFELY. Nature 584, 430–436 (2020).

Acknowledgements:

This study was supported by Pfizer, Sanofi, Novartis, Gilead, Biogen and Bristol-Myers Squibb.

We thank all the patients and health professionals contributing to SCQM.

Disclosure of Interests:

Eleftherios Papagiannoulis: None declared, Adrian Ciurea Speakers bureau: Abbvie, Eli Lilly, MSD, Novartis, Pfizer, Diana Dan: None declared, Axel Finckh: None declared, Benoit GILBERT: None declared, Isabell von Loga Consultant of: Deloitte Consulting AG., Cathy Melong Pianta Taleng: None declared, Almut Scherer Consultant of: Pfizer, Employee of: BMS (2007-2008), Kim Lauper Consultant of: Gilead Galapagos, Grant/research support from: AbbVie. The SCQM foundation is supported by different companies https://www.scqm.ch/en/sponsoren/.

The Role of Nutritional Factors and Intestinal Microbiota in Rheumatoid Arthritis Development

Evidence about the role of nutritional factors and microbiota in autoimmune diseases, and in rheumatoid arthritis (RA) in particular, has grown in recent years, however many controversies remain. The aim of this review is to summarize the role of nutrition and of the intestinal microbiota in the development of RA. We will focus on selected dietary patterns, individual foods and beverages that have been most consistently associated with RA or with the occurrence of systemic autoimmunity associated with RA. We will also review the evidence for a role of the intestinal microbiota in RA development. We propose that diet and digestive microbiota should be considered together in research, as they interact and may both be the target for future preventive interventions in RA.

THU0203 REAL WORLD EFFECTIVENESS OF BARICITINIB IN THE SWISS RHEUMATOID ARTHRITIS REGISTER (SCQM-RA)

Background:

Patients with rheumatoid arthritis (RA) intolerant or not responding adequately to conventional synthetic DMARD (csDMARD) usually receive biological DMARDs (bDMARDs) or targeted synthetic DMARDs (tsDMARDs) as 2ndline. Baricitinib (BARI), a once-daily oral selective Janus kinase inhibitor, is efficient in randomised controlled trials but still lacks evidence for effectiveness in real world settings.

Objectives:

To characterise patients initiating treatment with BARI or other alternative bDMARDs, and to perform an analysis of drug maintenance.

Methods:

This is an observational, prospective, cohort study, within the Swiss Clinical Quality Management (SCQM) register.

All treatment courses (TC) initiated between 2017-09-01 and 2019-10-01 were considered, comparing TC with BARI (BARI group) to TC with alternative bDMARDs, either TNF inhibitors (TNFi group) or other mode of action bDMARDs (OMA group), excluding rituximab.

Baseline characteristics were compared using ANOVA or χ2 tests. The crude drug maintenance was assessed by survival analysis (Kaplan-Meier). To correct for potential confounding factors, a Cox proportional hazard model was used. Missing values were imputed using multiple imputation with chained equations.

Results:

During the study period, 979 TC were initiated (240 in BARI group, 461 in TNFi group and 278 in OMA group). BARI was prescribed to significantly older patients, with longer disease durations and more previous treatment failures (Table 1). Unadjusted drug maintenance was significantly shorter in the TNFi compared to the BARI group (log rank p = 0.019). After adjustment for potential confounding factors, the hazard of TNFi discontinuation remained higher than for BARI (Hazard Ratio (HR) 1.48 (95% CI = [1.05 – 2.09]; p = 0.02)). A similar trend was observed when comparing the OMA drugs to BARI, with a HR for discontinuation of 1.42 (95% CI = [0.98 – 2.05]; p = 0.06) (Figure 2). Covariates significantly associated with decreased drug maintenance were concomitant csDMARD and concomitant glucocorticoids (Figure 2).

Table 1.

Baseline characteristics of studied population

VariableCategoriesBaricitinib(TC = 240; 240 patients)Mean (SD)Otherwise: n %TNFi(TC = 461; 397 patients)Mean (SD)Otherwise: n %OMA bDMARDs(TC = 278; 253 patients)Mean (SD)Otherwise: n %P valuesConcomitant csDMARD at baseline45 %54 %46 %0.02Line of Therapy1st20 %46 %22 %<0.012nd22 %25 %26 %3rd14 %14 %26 %4thor later43 %16 %27 %Gender (female)80 %71 %74 %0.05Age59 (13)53 (14)59 (13)<0.01Seropositivity (ACPA and/or RF)75 %71 %79 %0.04HAQ-DI Score0.9 (0.7)0.7 (0.6)0.8 (0.6)0.02Disease duration (years)12 (10)9 (10)11 (9)<0.01CDAI baseline19 (10)15 (12)19 (14)0.09

Legend

TC = Treatment Courses. SD = Standard Deviation. TNFi = TNF inhibitors. OMA bDMARDs = Other Mode of Action biological DMARDs. csDMARD = conventional synthetic DMARD. ACPA = Anti Citrullinated Peptide Antibodies. RF = Rheumatoid Factor. HAQ-DI= Health Assessment Questionnaire Disability Index. CDAI = Clinical Disease Activity Index.

Conclusion:

In this preliminary analysis, baricitinib was prescribed to older patients, with longer disease durations, and more previous treatment failures compared to alternative bDMARDs. Baricitinib demonstrated a significantly higher drug maintenance than TNFi, while similar trend was observed in comparison to OMA drugs.

Conflict of interest:

This analysis has been made possible by financial support of Eli Lilly (Suisse) SA to the Geneva University Hospitals (HUG).

Disclosure of Interests: :

Benoit GILBERT: None declared, Kim Lauper: None declared, Delphine Courvoisier: None declared, Clementine Perrier Shareholder of: Share of Eli Lilly Company, Employee of: I am currently an employee of Eli Lilly Suisse SA, Rudiger Muller Consultant of: AbbVie, Nordic, Sandoz, Axel Finckh Grant/research support from: Pfizer: Unrestricted research grant, Eli-Lilly: Unrestricted research grant, Consultant of: Sanofi, AB2BIO, Abbvie, Pfizer, MSD, Speakers bureau: Sanofi, Pfizer, Roche, Thermo Fisher Scientific

Rationale and protocol of the ENGAGE study: a double-blind randomized controlled preference trial using a comprehensive cohort design to measure the effect of a cognitive and leisure-based intervention in older adults with a memory complaint

BACKGROUND

Leisure activities can be both enjoyable and cognitively stimulating, and participation in such activities has been associated with reduced age-related cognitive decline. Thus, integrating stimulating leisure activities in cognitive training programs may represent a powerful and innovative approach to promote cognition in older adults at risk of dementia. The ENGAGE study is a randomized controlled, double-blind preference trial with a comprehensive cohort design that will test the efficacy and long-term impact of an intervention that combines cognitive training and cognitively stimulating leisure activities.

METHODS

One hundred and forty-four older adults with a memory complaint will be recruited in Montreal and Toronto. A particular effort will be made to reach persons with low cognitive reserve. Participants will be randomly assigned to one of two conditions: cognitive + leisure training (ENGAGE-MUSIC/SPANISH) or active control (ENGAGE-DISCOVERY). The ENGAGE-MUSIC/SPANISH training will include teaching of mnemonic and attentional control strategies, casual videogames selected to train attention, and classes in music or Spanish as a second language. The ENGAGE-DISCOVERY condition will comprise psychoeducation on cognition and the brain, low-stimulating casual videogames and documentary viewing with discussions. To retain the leisure aspect of the activities, participants will be allowed to exclude either music or Spanish at study entry if they strongly dislike one of these activities. Participants randomized to ENGAGE-MUSIC/SPANISH who did not exclude any activity will be assigned to music or Spanish based on a second random assignment. Training will be provided in 24 2-h sessions over 4 months. Outcomes will be measured at baseline, at 4-month follow-up, and at 24-month follow-up. The primary outcome will be cognitive performance on a composite measure of episodic memory (delayed recall scores for words and face-name associations) measured at baseline and at the 4-month follow-up. Secondary outcomes will include a composite measure of attention (speed of processing, inhibition, dual tasking, and shifting), psychological health, activities of daily living, and brain structure and function and long-term maintenance measured at the 24-month follow-up. Information on cognitive reserve proxies (education and lifestyle questionnaires), sex and genotype (apolipoprotein (Apo)E4, brain-derived neurotrophic factor (BDNF), and catechol-O-methyltransferase (COMT)) will be collected and considered as moderators of training efficacy.

DISCUSSION

This study will test whether a program combining cognitive training with stimulating leisure activities can increase cognition and reduce cognitive decline in persons at risk of dementia.

TRIAL REGISTRATION

NCT03271190 . Registered on 5 September 2017.

[Fecal microbiota transplantation : current status and prospects]

Fecal microbiota transplantation (FMT) is approved as a safe and effective treatment of recurrent Clostridium difficile infections. The technique is now being studied for other indications, usually involving chronic inflammation, metabolic disorders, or autoimmunity, for which the gut microbiota appears to play a key role. We detail thereafter, according to their degree of evidence, the potential future indications, in which FMT has already been tried on Humans. Except for ulcerative colitis and metabolic syndrome, the methodology of the published trials is often insufficiently described and inhomogeneous. Further randomized placebo-controlled trials and standardization of practice will be needed to confirm these preliminary but encouraging results.

Prevotella copri in individuals at risk for rheumatoid arthritis

OBJECTIVES

Rheumatoid arthritis (RA) has been associated with a relative expansion of faecal Prevotellaceae. To determine the microbiome composition and prevalence of Prevotella spp. in a group of individuals at increased risk for RA, but prior to the development of the disease.

METHODS

In an ongoing cohort study of first-degree relatives (FDRs) of patients with RA, we identified 'FDR controls', asymptomatic and without autoantibodies, and individuals in pre-clinical RA stages, who had either developed anticitrullinated peptide antibodies or rheumatoid factor positivity and/or symptoms and signs associated with possible RA. Stool sampling and culture-independent microbiota analyses were performed followed by descriptive statistics and statistical analyses of community structures.

RESULTS

A total of 133 participants were included, of which 50 were categorised as 'FDR controls' and 83 in 'pre-clinical RA stages'. The microbiota of individuals in 'pre-clinical RA stages' was significantly altered compared with FDR controls. We found a significant enrichment of the bacterial family Prevotellaceae, particularly Prevotella spp., in the 'pre-clinical RA' group (p=0.04).

CONCLUSIONS

Prevotella spp. enrichment in individuals in pre-clinical stages of RA, before the onset of RA, suggests a role of intestinal dysbiosis in the development of RA.

Positive correlation between dispersal and body size in Green Frogs (Rana clamitans) naturally colonizing an experimental landscape

Dispersers are often assumed to have the mean phenotype observed across the entire metapopulation, despite growing evidence of dispersal–phenotype correlations. We examined three dispersal–phenotype correlations in Green Frogs (Rana clamitans Latreille, 1801 = Lithobates clamitans (Latreille, 1801)). Two were in traits that have been previously tied to fitness (body size and body condition), while a third (relative hindlimb length) has been linked to movement performance. We constructed a spatially dispersed array of experimental ponds in close proximity to source ponds known to support Green Frog breeding populations. Over the course of two breeding seasons (four sampling periods), we measured phenotypes of all Green Frogs that had colonized the experimental ponds and a sample of individuals from the source ponds. After only 1 month, a positive correlation was detected between dispersal and body size within the population of dispersers occupying the experimental ponds. After a 2nd month, this positive dispersal – body size correlation was also present when comparing the population of dispersers to the population of nondispersers remaining at the source ponds. Even if generated solely by plasticity, a positive correlation between dispersal and body size (a trait tightly linked to fitness) has the ability to alter metapopulation capacity and thus the probability of regional species persistence.

On the Habitability of Desert Varnish: A Combined Study by Micro-Raman Spectroscopy, X-ray Diffraction, and Methylated Pyrolysis-Gas Chromatography-Mass Spectrometry

In 2020, the ESA ExoMars and NASA Mars 2020 missions will be launched to Mars to search for evidence of past and present life. In preparation for these missions, terrestrial analog samples of rock formations on Mars are studied in detail in order to optimize the scientific information that the analytical instrumentation will return. Desert varnishes are thin mineral coatings found on rocks in arid and semi-arid environments on Earth that are recognized as analog samples. During the formation of desert varnishes (which takes many hundreds of years), organic matter is incorporated, and microorganisms may also play an active role in the formation process. During this study, four complementary analytical techniques proposed for Mars missions (X-ray diffraction [XRD], Raman spectroscopy, elemental analysis, and pyrolysis-gas chromatography-mass spectrometry [Py-GC-MS]) were used to interrogate samples of desert varnish and describe their capacity to sustain life under extreme scenarios. For the first time, both the geochemistry and the organic compounds associated with desert varnish are described with the use of identical sets of samples. XRD and Raman spectroscopy measurements were used to nondestructively interrogate the mineralogy of the samples. In addition, the use of Raman spectroscopy instruments enabled the detection of β-carotene, a highly Raman-active biomarker. The content and the nature of the organic material in the samples were further investigated with elemental analysis and methylated Py-GC-MS, and a bacterial origin was determined to be likely. In the context of planetary exploration, we describe the habitable nature of desert varnish based on the biogeochemical composition of the samples. Possible interference of the geological substrate on the detectability of pyrolysis products is also suggested. Key Words: Desert varnish-Habitability-Raman spectroscopy-Py-GC-MS-XRD-ExoMars-Planetary science. Astrobiology 17, 1123-1137.

Reversal of intramyocellular lipid accumulation by lipophagy and a p62-mediated pathway

We have previously observed the reversal of lipid droplet deposition in skeletal muscle of morbidly obese patients following bariatric surgery. We now investigated whether activation of autophagy is the mechanism underlying this observation. For this purpose, we incubated rat L6 myocytes over a period of 6 days with long-chain fatty acids (an equimolar, 1.0 mM, mixture of oleate and palmitate in the incubation medium). At day 6, the autophagic inhibitor (bafilomycin A1, 200 nM) and the autophagic activator (rapamycin, 1 μM) were added separately or in combination for 48 h. Intracellular triglyceride (TG) accumulation was visualized and quantified colorimetrically. Protein markers of autophagic flux (LC3 and p62) and cell death (caspase-3 cleavage) were measured by immunoblotting. Inhibition of autophagy by bafilomycin increased TG accumulation and also increased lipid-mediated cell death. Conversely, activation of autophagy by rapamycin reduced both intracellular lipid accumulation and cell death. Unexpectedly, treatment with both drugs added simultaneously resulted in decreased lipid accumulation. In this treatment group, immunoblotting revealed p62 degradation (autophagic flux), immunofluorescence revealed the colocalization of p62 with lipid droplets, and co-immunoprecipitation confirmed the interaction of p62 with ADRP (adipose differentiation-related protein), a lipid droplet membrane protein. Thus the association of p62 with lipid droplet turnover suggests a novel pathway for the breakdown of lipid droplets in muscle cells. In addition, treatment with rapamycin and bafilomycin together also suggested the export of TG into the extracellular space. We conclude that lipophagy promotes the clearance of lipids from myocytes and switches to an alternative, p62-mediated, lysosomal-independent pathway in the context of chronic lipid overload (*P<0.05, **P<0.01, ***P<0.001, ****P<0.0001).

Organic and mineral imprints in fossil photosynthetic mats of an East Antarctic lake

Lacustrine microbial mats in Antarctic ice-free oases are considered modern analogues of early microbial ecosystems as their primary production is generally dominated by cyanobacteria, the heterotrophic food chain typically truncated due to extreme environmental conditions, and they are geographically isolated. To better understand early fossilization and mineralization processes in this context, we studied the microstructure and chemistry of organo-mineral associations in a suite of sediments 50-4530 cal. years old from a lake in Skarvsnes, Lützow Holm Bay, East Antarctica. First, we report an exceptional preservation of fossil autotrophs and their biomolecules on millennial timescales. The pigment scytonemin is preserved inside cyanobacterial sheaths. As non-pigmented sheaths are also preserved, scytonemin likely played little role in the preservation of sheath polysaccharides, which have been cross-linked by ether bonds. Coccoids preserved thylakoids and autofluorescence of pigments such as carotenoids. This exceptional preservation of autotrophs in the fossil mats argues for limited biodegradation during and after deposition. Moreover, cell-shaped aggregates preserved sulfur-rich nanoglobules, supporting fossilization of instable intracellular byproducts of chemotrophic or phototrophic S-oxidizers. Second, we report a diversity of micro- to nanostructured CaCO3 precipitates intimately associated with extracellular polymeric substances, cyanobacteria, and/or other prokaryotes. Micro-peloids Type 1 display features that distinguish them from known carbonates crystallized in inorganic conditions: (i) Type 1A are often filled with globular nanocarbonates and/or surrounded by a fibrous fringe, (ii) Type 1B are empty and display ovoid to wrinkled fringes of nanocrystallites that can be radially oriented (fibrous or triangular) or multilayered, and (iii) all show small-size variations. Type 2 rounded carbonates 1-2 μm in diameter occurring inside autofluorescent spheres interpreted as coccoidal bacteria may represent fossils of intracellular calcification. These organo-mineral associations support organically driven nanocarbonate crystallization and stabilization, hence providing potential markers for microbial calcification in ancient rocks.

Structural and Dynamic Approaches of Molten Salts by High Temperature Spectroscopies

The combination of 27AI NMR expriments and Molecular Dynamics simulation confirms the exis-tence of penta-coordinated Aluminium in several molten aluminium oxides. In the case of fluoroalumi-nate molten salts, NMR and Raman spectroscopies provide complementary approaches leading to a structural description in term of AIF− 4, AlF5 2-and AlF6 3−species.

Systematic molecular and cytogenetic screening of 100 patients with marfanoid syndromes and intellectual disability

The association of marfanoid habitus (MH) and intellectual disability (ID) has been reported in the literature, with overlapping presentations and genetic heterogeneity. A hundred patients (71 males and 29 females) with a MH and ID were recruited. Custom-designed 244K array-CGH (Agilent®; Agilent Technologies Inc., Santa Clara, CA) and MED12, ZDHHC9, UPF3B, FBN1, TGFBR1 and TGFBR2 sequencing analyses were performed. Eighty patients could be classified as isolated MH and ID: 12 chromosomal imbalances, 1 FBN1 mutation and 1 possibly pathogenic MED12 mutation were found (17%). Twenty patients could be classified as ID with other extra-skeletal features of the Marfan syndrome (MFS) spectrum: 4 pathogenic FBN1 mutations and 4 chromosomal imbalances were found (2 patients with both FBN1 mutation and chromosomal rearrangement) (29%). These results suggest either that there are more loci with genes yet to be discovered or that MH can also be a relatively non-specific feature of patients with ID. The search for aortic complications is mandatory even if MH is associated with ID since FBN1 mutations or rearrangements were found in some patients. The excess of males is in favour of the involvement of other X-linked genes. Although it was impossible to make a diagnosis in 80% of patients, these results will improve genetic counselling in families.

Tricking the guard: exploiting plant defense for disease susceptibility

Typically, pathogens deploy virulence effectors to disable defense. Plants defeat effectors with resistance proteins that guard effector targets. We found that a pathogen exploits a resistance protein by activating it to confer susceptibility in Arabidopsis. The guard mechanism of plant defense is recapitulated by interactions among victorin (an effector produced by the necrotrophic fungus Cochliobolus victoriae), TRX-h5 (a defense-associated thioredoxin), and LOV1 (an Arabidopsis susceptibility protein). In LOV1's absence, victorin inhibits TRX-h5, resulting in compromised defense but not disease by C. victoriae. In LOV1's presence, victorin binding to TRX-h5 activates LOV1 and elicits a resistance-like response that confers disease susceptibility. We propose that victorin is, or mimics, a conventional pathogen virulence effector that was defeated by LOV1 and confers virulence to C. victoriae solely because it incites defense.

Multistrain influenza protection induced by a nanoparticulate mucosal immunotherapeutic

All commercial influenza vaccines elicit antibody responses that protect against seasonal infection, but this approach is limited by the need for annual vaccine reformulation that precludes efficient responses against epidemic and pandemic disease. In this study we describe a novel vaccination approach in which a nanoparticulate, liposome-based agent containing short, highly conserved influenza-derived peptides is delivered to the respiratory tract to elicit potent innate and selective T cell-based adaptive immune responses. Prepared without virus-specific peptides, mucosal immunostimulatory therapeutic (MIT) provided robust, but short-lived, protection against multiple, highly lethal strains of influenza in mice of diverse genetic backgrounds. MIT prepared with three highly conserved epitopes that elicited virus-specific memory T-cell responses but not neutralizing antibodies, termed MITpep, provided equivalent, but more durable, protection relative to MIT. Alveolar macrophages were more important than dendritic cells in determining the protective efficacy of MIT, which induced both canonical and non-canonical antiviral immune pathways. Through activation of airway mucosal innate and highly specific T-cell responses, MIT and MITpep represent novel approaches to antiviral protection that offer the possibility of universal protection against epidemic and pandemic influenza.

Ataxie cérébelleuse révélant un syndrome de Wolfram

INTRODUCTION

Wolfram syndrome is a genetic disease with recessive autosomic transmission, associating early-onset diabetes mellitus and bilateral optical atrophy.

CASE REPORT

We report the case of a 47-year-old patient for whom we diagnosed a Wolfram syndrome in view of a late neurological syndrome in association with ataxia and bilateral horizontal nystagmus. The brain resonance magnetic imaging revealed a major atrophy of the brainstem and cerebellum.

CONCLUSION

Wolfram syndrome is a rare pathology, with fatal consequences before the age of 50. The association of diabetes mellitus and optical atrophy, especially when there are other symptoms (ataxia, deafness, diabetes insipidus, neuropsychiatric manifestations or urinary tract disorders) should lead to this diagnosis and to carry out a genetic confirmation.

Survey of the frequency of USH1 gene mutations in a cohort of Usher patients shows the importance of cadherin 23 and protocadherin 15 genes and establishes a detection rate of above 90%

BACKGROUND

Usher syndrome, a devastating recessive disorder which combines hearing loss with retinitis pigmentosa, is clinically and genetically heterogeneous. Usher syndrome type 1 (USH1) is the most severe form, characterised by profound congenital hearing loss and vestibular dysfunction.

OBJECTIVE

To describe an efficient protocol which has identified the mutated gene in more than 90% of a cohort of patients currently living in France.

RESULTS

The five genes currently known to cause USH1 (MYO7A, USH1C, CDH23, PCDH15, and USH1G) were tested for. Disease causing mutations were identified in 31 of the 34 families referred: 17 in MYO7A, 6 in CDH23, 6 in PCDH15, and 2 in USH1C. As mutations in genes other than myosin VIIA form nearly 50% of the total, this shows that a comprehensive approach to sequencing is required. Twenty nine of the 46 identified mutations were novel. In view of the complexity of the genes involved, and to minimise sequencing, a protocol for efficient testing of samples was developed. This includes a preliminary linkage and haplotype analysis to indicate which genes to target. It proved very useful and demonstrated consanguinity in several unsuspected cases. In contrast to CDH23 and PCDH15, where most of the changes are truncating mutations, myosin VIIA has both nonsense and missense mutations. Methods for deciding whether a missense mutation is pathogenic are discussed.

CONCLUSIONS

Diagnostic testing for USH1 is feasible with a high rate of detection and can be made more efficient by selecting a candidate gene by preliminary linkage and haplotype analysis.

Maternal mosaicism for mutations in the ARX gene in a family with X linked mental retardation

We describe two brothers with mental retardation (MR) due to a c.428_451dup24 in the ARX gene. The mother did not apparently carry the mutation, as determined by dHPLC and by fragment size analysis. Using semiquantitative fluorescent PCR, we show however that 4% of her lymphocytes and 24% of her fibroblasts harbored the duplication. We thus show that the mother displays somatic mosaicism for the duplication thereby highlighting the need to reconsider the molecular screening in sporadic cases of MR.

Topical antiinflammatory and analgesic activities ofCopaifera duckei dwyer

The oleoresin of several Copaifera species is used widely in the Amazonian Region mainly as a topical antiinflammatory and healing agent. The topical analgesic and antiinflammatory activities of Copaifera duckei oleoresin, whose terpenoidal chemical composition has been characterized, are now examined. Antiinflammatory activity was evaluated in rats using the carrageenin-induced paw edema and the granuloma tests, and in mice by the croton oil-induced dermatitis test. Analgesic activity was determined in mice using the writhing test method. In the carrageenin-induced edema and granuloma tests the oleoresin in a dose of 1,802 mg/kg inhibited the edema by 18% and granuloma by 42% (p < 0.05), this last result similar to that observed with dexamethasone. Topical doses of 517 mg/kg, 1,035 mg/kg and 1,802 mg/kg produced 52%, 58% and 62% (p < 0.05) reduction of the edema induced by croton oil, respectively, and 48%, 56% and 65% inhibition of the writhing process (p < 0.05). These results suggest that the Copaifera duckei oleoresin has topical antiinflammatory and analgesic activities.