Novel regulatory therapies for prevention of Graft-versus-host disease

Graft-versus-host disease is one of the major transplant-related complications in allogeneic hematopoietic stem cell transplantation. Continued efforts have been made to prevent the occurrence of severe graft-versus-host disease by eliminating or suppressing donor-derived effector T cells. Conventional immunosuppression does not adequately prevent graft-versus-host disease, especially in mismatched transplants. Unfortunately, elimination of donor-derived T cells impairs stem cell engraftment, and delays immunologic reconstitution, rendering the recipient susceptible to post-transplant infections and disease relapse, with potentially lethal consequences. In this review, we discuss the role of dynamic immune regulation in controlling graft-versus-host disease, and how cell-based therapies are being developed using regulatory T cells and other tolerogenic cells for the prevention and treatment of graft-versus-host disease. In addition, advances in the design of cytoreductive conditioning regimens to selectively target graft-versus-host disease-inducing donor-derived T cells that have improved the safety of allogeneic stem cell transplantation are reviewed. Finally, we discuss advances in our understanding of the tolerogenic facilitating cell population, a phenotypically and functionally distinct population of bone marrow-derived cells which promote hematopoietic stem cell engraftment while reducing the risk of graft-versus-host disease

Sensitive Assay for Mycoplasma Detection in Mammalian Cell Culture

Mycoplasma contamination in mammalian cell cultures is often overlooked yet is a serious issue which can induce a myriad of cellular changes leading to false interpretation of experimental results. Here we present a simple and sensitive assay to monitor mycoplasma contamination (mycosensor) based on degradation of the Gaussia luciferase reporter in the conditioned medium of cells. This assay proved to be more sensitive as compared to a commercially-available bioluminescent assay in detecting mycoplasma contamination in seven different cell lines. The Gaussia luciferase mycosensor assay provides an easy tool to monitor mammalian cells contaminants in a high-throughput fashion