C3b complexation diversifies naturally processed T cell epitopes.

International audienceIn addition to its well-established role in innate immunity, the complement component C3 is of critical importance in modulating the humoral response. In this study, we examined the effect of C3b linkage to tetanus toxin (TeNT) in the production of antigenic peptides inside human APC. We purified HLA-DR associated peptides isolated either from TeNT or TeNT-C3b pulsed cells. This study revealed that TeNT-C3b derived antigenic peptides are different and more numerous than TeNT derived peptides. This increased production of antigenic peptides correlated with a C3b-induced TeNT modification of proteolysis. These findings argue in favour of a new role for C3b in the modulation of T cell epitope during antigen processing and presentation

Increase in BDNF-mediated TrkB signaling promotes epileptogenesis in a mouse model of mesial temporal lobe epilepsy.

International audienceMesio-temporal lobe epilepsy (MTLE), the most common drug-resistant epilepsy syndrome, is characterized by the recurrence of spontaneous focal seizures after a latent period that follows, in most patients, an initial insult during early childhood. Many of the mechanisms that have been associated with the pathophysiology of MTLE are known to be regulated by brain-derived neurotrophic factor (BDNF) in the healthy brain and an excess of this neurotrophin could therefore play a critical role in MTLE development. However, such a function remains controversial as other studies revealed that BDNF could, on the contrary, exert protective effects regarding epilepsy development. In the present study, we further addressed the role of increased BDNF/TrkB signaling on the progressive development of hippocampal seizures in the mouse model of MTLE obtained by intrahippocampal injection of kainate. We show that hippocampal seizures progressively developed in the injected hippocampus during the first two weeks following kainate treatment, within the same time-frame as a long-lasting and significant increase of BDNF expression in dentate granule cells. To determine whether such a BDNF increase could influence hippocampal epileptogenesis via its TrkB receptors, we examined the consequences of (i) increased or (ii) decreased TrkB signaling on epileptogenesis, in transgenic mice overexpressing the (i) TrkB full-length or (ii) truncated TrkB-T1 receptors of BDNF. Epileptogenesis was significantly facilitated in mice with increased TrkB signaling but delayed in mutants with reduced TrkB signaling. In contrast, TrkB signaling did not influence granule cell dispersion, an important feature of this mouse model which is also observed in most MTLE patients. These results suggest that an increase in TrkB signaling, mediated by a long-lasting BDNF overexpression in the hippocampus, promotes epileptogenesis in MTLE

Risk of new or recurrent cancer under immunosuppressive therapy in patients with IBD and previous cancer.

International audienceOBJECTIVE: To explore the risk of new or recurrent cancer among patients with IBD and previous cancer, exposed or not to immunosuppressants. DESIGN: Among the 17 047 patients of the CESAME prospective observational cohort who were enrolled from May 2004 to June 2005, and followed-up until December 2007, we identified 405 patients with cancer diagnosed previous to study entry. We calculated the rates of incident cancer in patients with or without previous cancer, and we assessed by survival analysis and nested case-control study the impact of immunosuppressants on the risk of incident new or recurrent cancer in patients with previous cancer. RESULTS: The rate of incident cancer was 21.1/1000 patient-years (PY) and 6.1/1000 PY in patients with and without previous cancer, respectively. The multivariate-adjusted HR of incident cancer between patients with and without previous cancer was 1.9 (95% CI 1.2 to 3.0, p=0.003). Among patients with previous cancer, the rates of new and recurrent cancers were, respectively, 13.2/1000 PY and 6.0/1000 PY in the 312 patients who were not taking immunosuppressant at the time of study entry, and 23.1/1000 PY and 3.9/1000 PY in the 93 patients treated with immunosuppressants at study entry. There was no significant association between the exposure to immunosuppressants and the risk of new or recurrent cancer. CONCLUSIONS: Patients with IBD with a history of cancer are at increased risk of developing any (new or recurrent) cancer, with a predominant incidence of new cancers. Treatment with immunosuppressants has no overall major impact per se on this risk

Early Administration of Azathioprine vs Conventional Management of Crohn's Disease: a Randomized Controlled Trial.

International audienceBACKGROUND: & Aims: Immunomodulator therapy is effective for patients with Crohn's disease, but has not been shown to affect disease progression-presumably because it is given too late after diagnosis. We compared the efficacy of early treatment (within 6 mo after diagnosis) with azathioprine vs conventional management of patients at high risk for disabling disease. METHODS: We performed an open-label trial of adults with a diagnosis of Crohn's disease for less than 6 months who were at risk for disabling disease. From July 2005 through November 2010, patients at 24 French centers were randomly assigned to groups given azathioprine (2.5 mg/kg/day, n=65) or conventional management (placed on azathioprine only in cases of steroid-dependency, chronic active disease, with frequent flares, poor response to steroids, or development of severe perianal disease) (controls, n=67). The primary endpoint was the proportion of trimesters spent in steroid-free and anti-tumor necrosis factor (TNF)-free remission during the first 3 years after inclusion. RESULTS: During 3 y follow-up period, 16 patients in the azathioprine group were switched to mercaptopurine or methotrexate therapy, because of intolerance or poor efficacy. Forty-one controls required immunosuppressants (61%; median time to first prescription, 11 months). In the azathioprine group, a median 67% of trimesters were spent in remission (interquartile range, 11%-85%), compared with 56% in the control group (interquartile range, 29%-73%) (P=.69). Among secondary outcomes, a higher cumulative proportion of patients in the azathioprine group were free of perianal surgery than in the control group (96%±3% and 82%±6% at month 36, respectively; P=.036). The cumulative proportions of patients free of intestinal surgery and anti-TNF therapy did not differ between groups. CONCLUSION: Based on results from a clinical trial, administration of azathioprine within 6 months diagnosis of Crohn's disease was no more effective than conventional management in increasing time of clinical remission

Real-World Experience of Bevacizumab as First-Line Treatment for Ovarian Cancer: The GINECO ENCOURAGE Cohort of 468 French Patients

International audienceIntroduction: Bevacizumab-containing therapy is considered a standard-of-care front-line option for stage IIIB–IV ovarian cancer based on results of randomized phase 3 trials. The multicenter non-interventional ENCOURAGE prospective cohort study assessed treatment administration and outcomes in the French real-world setting.Patients and Methods: Eligible patients were aged ≥ 18 years with planned bevacizumab-containing therapy for newly diagnosed ovarian cancer. The primary objective was to assess the safety profile of front-line bevacizumab in routine clinical practice; secondary objectives were to describe patient characteristics, indications/contraindications for bevacizumab, treatment regimens and co-medications, follow-up and monitoring, progression-free survival, and treatment at recurrence. In this non-interventional study, treatment was administered as chosen by the investigator and participation in the trial had no influence on the management of the disease.Results: Of 1,290 patients screened between April 2013 and February 2015, 468 were eligible. Most patients (86%) received bevacizumab 15 mg/kg every 3 weeks or equivalent, typically with carboplatin (99%) and paclitaxel (98%). The median duration of bevacizumab was 12.2 (range 0–28, interquartile range 6.9–14.9) months; 8% of patients discontinued bevacizumab because of toxicity. The most common adverse events were hypertension (38% of patients), fatigue (35%), and bleeding (32%). There were no treatment-related deaths. Most physicians (90%) reported blood pressure measurement immediately before each bevacizumab infusion and almost all (97%) reported monitoring for proteinuria before each bevacizumab infusion. Median progression-free survival was 17.4 (95% CI, 16.4–19.1) months. The 3-year overall survival rate was 62% (95% CI, 58–67%). The most commonly administered chemotherapies at recurrence were carboplatin and pegylated liposomal doxorubicin.Discussion: Clinical outcomes and tolerability with bevacizumab in this real-life setting are consistent with randomized trial results, notwithstanding differences in the treated patient population and treatment schedule

Immunogenicity and Safety of Influenza Vaccine in Inflammatory Bowel Disease Patients Treated or not with Immunomodulators and/or Biologics: A Two-year Prospective Study.

International audienceData on the efficacy and safety of seasonal influenza vaccines in patients with inflammatory bowel disease (IBD) remain scarce. The aim of the study was to evaluate the impact of immunosuppressive (IS) therapeutics on serological response to 2-year influenza vaccination in IBD adults. A multicentre prospective study performed in 255 IBD adults (18-64 years) receiving the trivalent influenza vaccine in the years 2009-2010 and 2010-2011. Haemagglutination inhibition (HI) titres were assessed before and 3 weeks and 6 months after vaccination. At inclusion, 31 patients were receiving no IS treatment (Group A), 77 were receiving IS treatment without anti-TNF (Group B) and 117 were receiving anti-tumour necrosis factor (TNF) treatment with or without IS treatment (Group C). Three weeks after the first vaccination, rates of seroprotection were 77, 75 and 66% for strain A/H1N12007 (p = 0.35), 77, 68 and 52% for strain A/H3N2 (p = 0.014) and 97, 96 and 95% for strain B (p = 0.99) in Groups A, B and C, respectively. Seroconversion rates for A/H1N12007 (67, 64 and 54%; p = 0.28), A/H3N2 (63, 50 and 41%; p = 0.074) and strain B (63, 76 and 60%; p = 0.078) were not significantly different among treatment groups. At 6 months after vaccination, seroprotection rates were lower in Group C compared with Groups A and B. Comparable results were observed for the second year of vaccination. No impact on Harvey-Bradshaw and Mayo scores was detected. Influenza vaccine yielded high seroprotection rates in IBD patients. Persistence of seroprotection was lower in patients with anti-TNF treatment. ClinicalTrials.gov, number NCT01022749