The risk of infections in multiple myeloma before and after the advent of novel agents: a 12-year survey.

Infections represent a major cause of morbidity and mortality in multiple myeloma and are linked to both therapy- and disease-related factors. Although it has been suggested that the rate of infections increased since the introduction of novel agents, controversies still exist. To better assess the risk factors associated with infections in the era of novel agents, we conducted a large retrospective analysis of 479 myeloma patients treated at Jena University Hospital over a period of 12 years. During their disease history, 65% of patients developed at least one infection, and 37% of therapies were associated with at least one infectious episode. The rate of infections was constant over the years, with no increase in infectious complications after the routine implementation of novel agents. Infections were mainly bacterial and strongly associated with high disease burden, relapsed disease, and treatment with high-dose chemotherapy. Varicella zoster virus (VZV) reactivations occurred late during treatment (median time between high-dose chemotherapy and VZV reactivation 6 months, range 0-44 months), and fewer patients developed a VZV reactivation after 2009 (p = 0.001). Infections are still one of the major causes of morbidity in myeloma patients, and prophylactic measures are urgently needed to reduce this potentially lethal complication.

Human Dendritic Cells Synergistically Activated by FVIII Plus LPS Induce Activation of Autologous CD4+ T Cells.

The most severe side effect in haemophilia A (HA) treatment is the development of anti-factor VIII antibodies, also called inhibitors. Why inhibitors develop in a proportion of treated HA patients and how this can be prevented remains largely unanswered. Among numerous theories, the presence of immunological danger signals, associated with events such as surgery or infection, has been proposed to play a role. In this study, we demonstrate that human dendritic cells (DC) synergistically activated by a combination of factor VIII (FVIII) concentrate plus the bacterial danger signal lipopolysaccharide (LPS) induce a significantly stronger activation of autologous CD4+ T cells than DC pretreated with FVIII or LPS alone. The observed T cell activation is dependent on antigen processing, presentation on MHC class II molecules and costimulation via CD86. Of note, FVIII plus LPS pretreated DC predominantly induce the activation of memory T cells and a minor proportion of naive T cells. Collectively, our data support a model in which immunological danger signals plus FVIII concentrates synergistically increase human CD4+ T cell responses to FVIII protein.