Immunomodulatory Drugs Restore Effector Cell Immune Functions In Myeloma Patients With Low Disease Burden After Autologous Stem Cell Transplantation

The micro-environment in multiple myeloma (MM) is highly immunosuppressive with increased numbers of regulatory T cells (Tregs) and myeloid derived suppressor cells (MDSCs) favoring tumorcell survival and hampering immunotherapeutic strategies such as dendritic cell vaccination. Immunomodulatory drugs (IMiDs) are known to enhance T- and NK-cell function. In this study we evaluated the effects of low dose (0.5 microM) lenalidomide (Len) and pomalidomide (Pom) on the functionality of CD8+ and CD4+ T cells, MDSCs, Tregs and ex-vivo generated mononuclear derived dendritic cells (moDCs) obtained from MM patients after first autologous stem cell transplantation (ASCT). Peripheral blood mononuclear cell fractions were obtained by leukapheresis from 9 MM patients (age 29-62 years), in very good partial response (4/9) or complete response (5/9) after ASCT.