Altschul SF, Gish W, Miller W, Myers EW, DJ L: Basic local alignment search tool. J Mol Biol 1990,215(3):403–10.PubMed 47. Thompson JD, Higgins DG, Gibson TJ: CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position-specific gap penalties and weight matrix choice. Nucl Acids Res 1994, 22:4673–4680.CrossRefPubMed 48. Felsentein J: Phylip; Phylogeny Inference Package Version 3.2. Cladistics 1989, 5:164–166. 49. Creevey CJ, McInerney JO: Clann: investigating phylogenetic information through supertree analyses. Bioinformatics 2005, 21:390–392.CrossRefPubMed Authors’ contributions OOS Primaryauthor, experimental design and contributed to all experiments. JOC reviewed, sugar

metabolism work and intellectual Sirolimus research buy contribution to the manuscript. ASV Contributed to

experiments. OMcA contributed to experiments and reviewed manuscript. LS contributed to experiments. PK contributed to experiments. MC Selleckchem Bioactive Compound Library experimental design and intellectual input. GF Principal investigator and intellectual input RPR Principal investigator and intellectual input. TB Principal investigator and intellectual input. All authors have read and approved the final manuscript.”
“Background Cryptococcus neoformans is an encapsulated yeast that is a facultative intracellular pathogen and a frequent cause of human disease in immunocompromised patients [1, 2]. Macrophages are essential for effective host defense against C. neoformans in humans [3, 4]. However, murine macrophages have been shown to be permissive for intracellular replication of C. neoformans, which can subsequently be extruded from or lyse the macrophages [2, 5–8]. In this regard, C. neoformans has a unique intracellular pathogenic strategy that involves cytoplasmic accumulation of polysaccharide-containing

vesicles and intracellular replication leading mafosfamide to the formation of large phagosomes where multiple Cryptococcal cells are present [5]. Our group and others have recently reported that after C. neoformans ingestion by macrophages, the yeast replicates and is subsequently extruded, in a process whereby both the yeast and macrophages survive [8, 9]. Moreover, it was also recently discovered that C. neoformans can spread from an infected to an uninfected murine macrophage cell [9, 10]. Here we further extend our extrusion studies to human peripheral blood monocytes (HPBMs) and report that as in murine macrophages, the interaction between human monocytes and C. neoformans leads to ingestion, intracellular replication, and polysaccharide shedding of C. neoformans, followed by cell to cell spread and extrusion of C. neoformans. The occurrence of phagosomal ‘extrusion’ in human peripheral blood monocytes suggests a central role for this phenomenon in the propagation and dissemination of this fungal pathogen. C. neoformans has a novel intracellular strategy that, to date has no precedent in other well-characterized intracellular pathogens. Since C.