BackgroundRecent findings in cancer immunotherapy have reinforced the hypothesis that the immune system is able to control most cancers. Immunomodulatory antibodies can enhance immune responses, having the potential to generate anti-cancer immunity.1–4Materials and MethodsMost current studies addressing this question are performed in murine mouse model systems or use in vitro culture systems, which do not reflect the human in vivo situation, potentially leading to results that cannot be fully translated into human cancer therapy. Therefore, it is necessary to establish a new mouse model, which allows the study of cancer immunotherapy in the context of a human immune system. We focused on the establishment of a humanized mouse model, in which different immunomodulatory antibodies can be tested in the presence of a human immune system.ResultsFirst experiments concerning the suitability to test immunomodulatory antibodies in the humanized mouse model, revealed that effects of checkpoint-control antibody a-CTLA-4 were similar to the effects seen in patients of clinical studies. To analyse the anti-tumor activities of immunomodulatory antibodies in vivo we are establishing a human melanoma-like tumor model in humanized mice.ConclusionsThis enables us to test the efficacy of immunomodulatory agonistic antibodies (such as CP-870,893) and checkpoint control antibodies (such as anti-CTLA-4) in eliminating a melanoma-like tumor. Furthermore, parameters like tumor infiltrating human cells und cytokine/chemokine production can be analysed.ReferencesSchuster M, Nechansky A, Loibner H. Cancer immunotherapy. Biotechnol J 2006;1:138–147.Mellman I, Coukos G, Dranoff G. Cancer immunotherapy comes of age. Nature rev 2011;480:480–489.Finn OJ. Immuno-oncology: understanding the function and dysfunction of the immune system in cancer. Annals of Oncology 2012;23:vii6–vii9.Langer LF, Clay TM, Morse MA. Update on anti-CTLA-4 in clinical trials. Expert Opin Biol Ther 2007;8:1245–1256.Disclosure InformationC. Reitinger: None. F. Nimmerjahn: None.
Evaluation of safety and efficacy of RNAi against HIV-1 in the human immune system (Rag-2-/-γc-/-) mouse model
