Long-term exposure to monoclonal anti-TNF is associated with an increased risk of lymphoma in BAFF-transgenic mice.

The impact of treatment on the risk of lymphoma in patients with rheumatoid arthritis (RA) is unclear. Here, we aimed to assess if the risk of lymphoma differs according to the type of tumor necrosis factor inhibitor (TNFi), comparing monoclonal anti-TNF antibodies to the soluble TNF receptor. We used B cell activating factor belonging to the TNF family (BAFF)-transgenic (Tg) mice as a model of autoimmunity-associated lymphoma. Six-month-old BAFF-Tg mice were treated with TNFi for 12 months. Histological examination of the spleen, assessment of the cellular composition of the spleen by flow cytometry and assessment of B cell clonality were performed at euthanasia. Crude mortality and incidence of lymphoma were significantly higher in mice treated with monoclonal anti-TNF antibodies compared to both controls and mice treated with the soluble TNF receptor, even at a high dose. Flow cytometry analysis revealed decreased splenic macrophage infiltration in mice treated with monoclonal anti-TNF antibodies. Overall, this study demonstrates, for the first time, that a very prolonged treatment with monoclonal anti-TNF antibodies increase the risk of lymphoma in B cell-driven autoimmunity. These data suggest a closer monitoring for lymphoma development in patients suffering from B cell-driven autoimmune disease with long-term exposure to monoclonal anti-TNF antibodies.

Duration of combination therapy and risk of treatment failure in patients with inflammatory bowel disease.

BACKGROUND: Patients who receive infliximab (IFX) combined with a thiopurine, for inflammatory bowel disease, have a better clinical response and less frequent immunization towards IFX than those treated with IFX alone. The benefits of combination therapy must be weighed against the risks of infection and cancer. We studied the association between the duration of combination therapy and the risk of treatment failure by two year from initiation. METHODS: Participants had Crohn's disease or ulcerative colitis and were in clinical and biological remission, 6 months after initiation of combination therapy. The risk of subsequent treatment failure (i.e., undetectable trough IFX levels and/or clinical relapse followed by surgical treatment or switch of maintenance treatment) was estimated using Kaplan-Meier method and adjusted Hazard Ratios (aHRs), in patients whohadreceived 6 to 11 months vs. 12 months or more of combination therapy. We performed a similar analysis in which the follow-up was started at discontinuation of the immunosuppressant. RESULTS: Among 139 patients (48% women; median age 31.1), with a median follow-up of 18.9 months, we observed 26 treatment failures (including 15 patients with undetectable trough IFX levels). After adjustment for gender and type of immunomodulator, a shorter duration of combination therapy was not associated with a higher risk of treatment failure (aHR=0.42; 95% confidence interval (95%CI): 0.13-1.40; p=0.16). When the follow-up was started at discontinuation of the immunosuppressant, a combination therapy of 6-11 months was associated with a numerically lower risk of treatment failure as compared with a longer combination therapy (HR=0.12; 95%CI: 0.01-1.05; p=0.055). CONCLUSION: Our results do not show any benefit for continuation of combination therapy for more than 12 months after achieving clinical remission in IBD patients.

Gene Therapy of the ß-Hemoglobinopathies by Lentiviral Transfer of the ß(A(T87Q))-Globin Gene.

ß-globin gene disorders are the most prevalent inherited diseases worldwide and result from abnormal ß-globin synthesis or structure. Novel therapeutic approaches are being developed in an effort to move beyond palliative management. Gene therapy, by ex vivo lentiviral transfer of a therapeutic ß-globin gene derivative (ß(AT87Q)-globin) to hematopoietic stem cells, driven by cis-regulatory elements that confer high, erythroid-specific expression, has been evaluated in human clinical trials over the past 8 years. ß(AT87Q)-globin is used both as a strong inhibitor of HbS polymerization and as a biomarker. While long-term studies are underway in multiple centers in Europe and in the United States, proof-of-principle of efficacy and safety has already been obtained in multiple patients with ß-thalassemia and sickle cell disease.

Gene therapy of severe combined immunodeficiencies.

The concept that the outcome of a devastating disease can be modified by inserting a transgene into abnormal cells is appealing. However, the gene-transfer technologies that are available at present have limited the success of gene therapy so far. Nevertheless, severe combined immunodeficiencies are a useful model, because gene transfer can confer a selective advantage to transduced cells. In this way, a proof of concept for gene therapy has been provided.

Adenovirally transduced dendritic cells induce bispecific cytotoxic T lymphocyte responses against adenovirus and cytomegalovirus pp65 or against adenovirus and Epstein-Barr virus EBNA3C protein: a novel approach for immunotherapy.

Cytomegalovirus (CMV), Epstein-Barr virus (EBV), and adenovirus (Ad) cause significant morbidity and mortality in immunocompromised patients undergoing allogeneic stem cell transplantation. We have established a procedure to generate polyclonal cytotoxic T lymphocyte (CTL) populations with specificity against Ad and CMV or against Ad and EBV. Healthy donor-derived dendritic cells (DCs) were transduced with recombinant adenovirus encoding either CMV pp65 or EBV EBNA3C and used to stimulate autologous T cells. Stimulated T lymphocytes displayed specific simultaneous cytotoxicity against CMV and adenovirus and to a lesser extent against adenovirus and EBV. Recombinant vaccinia virus encoding individual adenovirus proteins showed that the T cell response to the adenovirus was directed mainly against the capsid protein hexon. The frequency of IFN-gamma-secreting T cells was 0.02% for adenovirus alone, and 0.05 and 0.14% for adenoviruses encoding EBNA3C and pp65, respectively. pp65-specific CTLs killed autologous fibroblasts infected with the laboratory strain CMV AD169. The culture conditions were specific as alloreactive T cells were not expanded. Therefore, this approach could be considered in order to generate efficient virus cytolytic T cells to be used as adoptive immunotherapy in transplanted patients.