Select members of the heat shock proteins (HSPs) family, such as gp96, elicit immune responses specific to their chaperoned peptides. While immunological effects of HSPs on antigen presenting cell (APCs) described to date have largely been demonstrated with cell lines or primary cells in culture, their collective responses in vitro have been consistent with priming immune responses. Here we examine the physiologically relevant APCs in mice that are targeted following vaccination with native, murine HSP and characterize those cells. Gp96 accesses the subcapsular region of the draining lymph node and is internalized predominantly by CD11b+ cells in this locale. Cells acquiring gp96 can transfer protective anti-tumor immunity to naïve mice by actively cross-presenting gp96-chaperoned peptides and providing co-stimulation. Our studies illustrate how HSPs act to alert the immune system of cellular damage and will be of paramount importance in immunotherapy of patients with cancer and infectious disease.

The genus Megasphaera harbors important spoilage organisms that cause beer spoilage by producing off flavors, undesirable aroma, and turbidity. Megasphaera cerevisiae is mainly found in nonpasteurized low-alcohol beer. In this study, we report the draft genome of the type strain of the genus, M. cerevisiae strain PAT 1T.