Regulation of the expression of chaperone gp96 in macrophages and dendritic cells

The chaperone function of the ER-residing heat shock protein gp96 plays an important role in protein physiology and has additionally important immunological functions due to its peptide-binding capacity. Low amounts of gp96 stimulate immunity; high quantities induce tolerance by mechanisms not fully understood. A lack of gp96 protein in intestinal macrophages (IMACs) from Crohn`s disease (CD) patients correlates with loss of tolerance against the host gut flora, leading to chronic inflammation. Since gp96 shows dose-dependent direction of immunological reactions, we studied primary IMACs and developed cell models to understand the regulation of gp96 expression. Induction of gp96-expression was higher in in vitro differentiated dendritic cells (i.v.DCs) than in in vitro differentiated macrophages (i.v.MACs), whereas monocytes (MOs) expressed only low gp96 levels. The highest levels of expression were found in IMACs. Lipopolysaccharide (LPS), muramyl dipeptide (MDP), tumour necrosis factor (TNF), and Interleukin (IL)-4 induced gp96-expression, while IL12, IL-17, IL-23 and interferon (IFN)-γ were not effective indicating that Th1 and Th17 cells are probably not involved in the induction of gp96. Furthermore, gp96 was able to induce its own expression. The ER-stress inducer tunicamycin increased gp96-expression in a concentration- and time-dependent manner. Both ulcerative colitis (UC) and CD patients showed significantly elevated gp96 mRNA levels in intestinal biopsies which correlated positively with the degree of inflammation of the tissue. Since gp96 is highly expressed on the one hand upon stress induction as during inflammation and on the other hand possibly mediating tolerance, these results will help to understand the whether gp96 plays a role in the pathophysiology of inflammatory bowel disease (IBD)

Microalgal immobilization methods

In this review, methods for the most common microalgal immobilization procedures are gathered and described. Passive (due to natural adherence of cells to surfaces) and active immobilization methods should be distinguished. Among active immobilization methods, calcium alginate entrapment is the most widely used method if living cells are intended to be immobilized, due to the chemical, optical, and mechanical characteristics of this substance. Immobilization in synthetic foams, immobilization in agar and carrageenan as well as immobilization in silica-based matrix or filters are also discussed and described. Finally, some considerations on the use of flocculation for microalgae are mentioned. © Springer Science+Business Media, New York 2013.Peer Reviewe

Beneficial soil microbiome for sustainable agricultural production

The projected increase in world population and the need to reduce the reliance on non-renewable inputs, such as synthetic agrochemicals, are challenging the current vision of agriculture. In particular, to achieve a fair and sustainable global food security, disruptive changes in crop production are unavoidable. A promising strategy proposes to exploit the metabolic capabilities of soil microbial communities, i.e., the microbiome, to conjugate stable yield with reduced impact on the agroecosystem. In this chapter, we introduce the microbiome populating the root-soil interface from an evolutionary perspective. Next, we discuss the molecular bases of plant-microbe interactions in soil and how these interactions impact plant growth, development and health. We illustrate how plant-probiotic members of the microbiome can be isolated from soil and further characterized for their biological activities, a key pre-requisite for translational applications. In addition, we focus on paradigmatic examples of soil microbes turned into inoculants for agriculture, their fate on soil, their impact on the native microbiome and the beneficial effects exerted on crop productio