Quadrangulosides A-F: new pregnane glycosides from Caralluma quadrangula.

The phytochemical investigation of Caralluma quadrangula aerial parts yielded six new pregnane glycosides, quadrangulosides A-F (1-6), in addition to nine known pregnane glycosides and three known flavone glycosides. Structures of isolated phyto-constituents were elucidated via spectroscopic 1D-, 2D-NMR and spectrometric ESI-MS spectra.

The influence of interferon-ß supplemented human dendritic cells on BCG immunogenicity.

INTRODUCTION: Tuberculosis (TB) remains a huge worldwide burden, despite extensive vaccination coverage with the Bacillus Calmette-Guérin (BCG), the only vaccine available against this disease, indicating that BCG-driven immunity is inadequate to protect the human population against TB. This underscore the critical necessitate to develop an improved TB vaccine, based on a better understanding of host-pathogen interactions and immune responses during mycobacterial infection. AIM OF THE WORK: To examine whether the exogenous addition of IFN-ß could improve dendritic cell (DC) response to Mycobacterium bovis (M. bovis) and to evaluate the effect induced by the infection of human DCs with M. bovis (with and without IFN-ß) and Mycobacterium tuberculosis (Mtb) on DC viability as well as to compare the ability of BCG and Mtb to provide DCs with a Th1-polarizing capacity through the assessment of the immunoregulatory cytokines interleukin (IL)-12, IL-10 and interferon-gamma (IFN-γ). METHODS: Immature DCs (iDCs) were generated in vitro using peripheral blood monocytes separated by anti-CD14-conjugated microbeads in the presence of granulocyte-macrophage-colony-stimulating factor (GM-CSF) and IL-4, cultured cells were analyzed using flow cytometry, then we tested DC viability after inoculation with M. bovis (with and without IFN-ß pretreatment) and Mtb using light microscopic examination and trypan blue exclusion method. Additionally, supernatants from infected-DCs cultures were analyzed for IFN-γ, IL-12 and IL-10 by ELISA. RESULTS: The viability of BCG-infected DCs was significantly higher than that of Mtb-infected DCs (61.55% vs 52.10%). BCG-infected DC produced significantly more IL-12 (p = 0.02) and less IL-10 (p = 0.01) compared with Mtb-infected cells. IFN-ß-pretreated BCG-infected DCs produced significantly larger amounts of IL-12 than did BCG-infected DCs (p = 0.03) and Mtb-infected cells (p < 0.001). CONCLUSION: IFN-ß improves DC functions following BCG infection, thus assuming that IFN-ß could be used as a vaccine adjuvant.