La transcriptase inverse des retrotransposons LINE (rôle dans la formation des pseudogènes et dans la mobilité des séquences non-codantes du génome humain)

CHATENAY M.-PARIS 11-BU Pharma. (920192101) / SudocSudocFranceF

Therapeutic Vaccination with TNF-Kinoid in TNF Antagonist-Resistant Rheumatoid Arthritis: A Phase II Randomized, Controlled Clinical Trial.

Active immunization, or vaccination, with tumor necrosis factor (TNF)-Kinoid (TNF-K) is a novel approach to induce polyclonal anti-TNF antibodies in immune-mediated inflammatory diseases. This study was performed to transfer the proof of concept obtained in mice model of rheumatoid arthritis (RA) into human. We designed a pilot study to demonstrate the feasibility of therapeutic vaccination in RA

Vaccination of metastatic melanoma patients with autologous dendritic cell (DC) derived-exosomes: results of thefirst phase I clinical trial.

BACKGROUND: DC derived-exosomes are nanomeric vesicles harboring functional MHC/peptide complexes capable of promoting T cell immune responses and tumor rejection. Here we report the feasability and safety of the first Phase I clinical trial using autologous exosomes pulsed with MAGE 3 peptides for the immunization of stage III/IV melanoma patients. Secondary endpoints were the monitoring of T cell responses and the clinical outcome. PATIENTS AND METHODS: Exosomes were purified from day 7 autologous monocyte derived-DC cultures. Fifteen patients fullfilling the inclusion criteria (stage IIIB and IV, HLA-A1+, or -B35+ and HLA-DPO4+ leukocyte phenotype, tumor expressing MAGE3 antigen) were enrolled from 2000 to 2002 and received four exosome vaccinations. Two dose levels of either MHC class II molecules (0.13 versus 0.40 x 1014 molecules) or peptides (10 versus 100 mug/ml) were tested. Evaluations were performed before and 2 weeks after immunization. A continuation treatment was performed in 4 cases of non progression. RESULTS: The GMP process allowed to harvest about 5 x 1014 exosomal MHC class II molecules allowing inclusion of all 15 patients. There was no grade II toxicity and the maximal tolerated dose was not achieved. One patient exhibited a partial response according to the RECIST criteria. This HLA-B35+/A2+ patient vaccinated with A1/B35 defined CTL epitopes developed halo of depigmentation around naevi, a MART1-specific HLA-A2 restricted T cell response in the tumor bed associated with progressive loss of HLA-A2 and HLA-BC molecules on tumor cells during therapy with exosomes. In addition, one minor, two stable and one mixed responses were observed in skin and lymph node sites. MAGE3 specific CD4+ and CD8+ T cell responses could not be detected in peripheral blood. CONCLUSION: The first exosome Phase I trial highlighted the feasibility of large scale exosome production and the safety of exosome administration

Difference from baseline for clinical assessments in anti-TNF antibody responders and non-responders.

<p>Post-hoc analyses: Mean changes in clinical assessments from baseline are shown at months 3, 6, and 12 for antibody responders (detectable anti-TNF antibodies at any time; gray bars) and for non-responders (white bars). (A) DAS28-CRP. (B) CRP. (C) Tender joints count. (D) Swollen joints count. (E) Patient’s global activity score. (F) Physician’s global activity score. (G) Patient assessment of pain. (H) Change in HAQ disability/function score. Error bars indicate standard error of the mean. P-values were determined by Wilcoxon rank-sum test. NS, not significant (p≥0.05). In responders, n = 19 at month 3, 16 at months 6 and 12 except at month 3 for Physician GAS n = 18 and for CRP n = 20. In non-responders, n = 17 at month 3 and 15 at months 6 and 12 except at month 6 n = 14 for CRP and DAS 28 score.</p

Study design.

<p>In the first stage, 8 patients were randomized 3∶1 to receive 90 µg TNF-K or placebo, in the second, 16 patients were randomized 3∶1 to receive 180 µg TNF-K or placebo, and in the third, 17 patients were randomized 3∶1 to receive 360 µg TNF-K or placebo. In each stage, patients were also randomized 1∶1 to receive 2 doses (day 0, 28) or 3 doses (day 0, 7, 28) (arrows). For stages 1 and 2, after 3 patients had been enrolled and no safety issues had been reported for at least 7 days, enrolment in the subsequent stage started in parallel. One patient randomized to receive 3 doses of 360 µg TNF-K withdrew consent prior to treatment. The principal analysis portion of the study continued up to day 84, and the follow-up portion continued up to month 12.</p

Humoral immune response to TNF.

<p>Patients were treated with 2 doses (days 0 and 28) or 3 doses (days 0, 7, and 28) of placebo or 90, 180, or 360 µg TNF-K. Anti-TNF antibody titers were determined by enzyme-linked immunosorbent assay. (A) GMTs. (B) Percent of patients in each treatment group with detectable anti-TNF antibodies (titer ≥200) up to month 3 (at study day 38, 56, or 84), at month 6, at month 12, or at any time up to month 12 (i.e., antibody responders).</p

Demographics of treated patients at baseline (day 0).

<p>Abbreviations: SD, standard deviation.</p><p>Demographics of treated patients at baseline (day 0).</p

T cell response to TNF.

<p>Peripheral blood mononuclear cells were collected on days 0 and 56 and treated in vitro with medium (control) or with 10 µg/mL TNF-K, TNF, or KLH. Lymphoproliferation was assessed after 72 h by ³H-thymidine incorporation. Shown is the stimulation index (fold-increase in lymphoproliferation vs. control) for cells from patients treated with placebo (n = 6) or TNF-K (n = 10).</p