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ZusammenfassungDas Prinzip der passiven Immunisierung ist seit dem 19. Jahrhundert bekannt und wird auch bei aktuellen Pandemien als Ansatz zur Prophylaxe und Therapie eingesetzt. Der Schutz wird hierbei übertragen durch Blut, Serum oder Plasma, welche Immunglobuline gegen spezifische Krankheitserreger, Bakterientoxine oder sonstige Antigene enthalten, sowie durch aus Humanplasma industriell aufgereinigte Immunglobuline. Die aktuell verwendeten Reinigungsverfahren für Immunglobuline aus Humanplasma beruhen auf der von Edwin J. Cohn entwickelten Fraktionierung von Plasma. Zur Gewinnung von Immunglobulinen mit hohen Antikörpertitern gegen spezifische Antigene, sogenannte Hyperimmunglobuline, muss zunächst Hyperimmunplasma gezielt von ausgewählten Spendern gewonnen werden. Diese Spender haben erhöhte Antikörpertiter gegen spezifische Krankheitserreger, Bakterientoxine oder sonstige Antigene, wenn sie im Rahmen einer vorangegangenen Infektion natürlich immunisiert wurden, einen zugelassenen Impfstoff zur Immunisierung erhalten haben oder gezielt zum Zweck der Plasmaspende immunisiert wurden. Aktuell sind in Deutschland, Österreich und der Schweiz Hyperimmunglobulinprodukte für verschiedene Anwendungen im Patienten zugelassen, von denen die meisten aus humanem Blutplasma gewonnen werden. Um die Herstellung der Produkte und damit letztlich die Behandlung der Patienten gewährleisten zu können, werden resiliente Lieferketten benötigt. Hierzu bedarf es unter anderem Änderungen in den Rahmenbedingungen für die Spenderimmunisierung in Deutschland.

Agriculture and the exploitation of natural resources have transformed tropical mountain ecosystems across the world, and the consequences of these transformations for biodiversity and ecosystem functioning are largely unknown1-3. Conclusions that are derived from studies in non-mountainous areas are not suitable for predicting the effects of land-use changes on tropical mountains because the climatic environment rapidly changes with elevation, which may mitigate or amplify the effects of land use4,5. It is of key importance to understand how the interplay of climate and land use constrains biodiversity and ecosystem functions to determine the consequences of global change for mountain ecosystems. Here we show that the interacting effects of climate and land use reshape elevational trends in biodiversity and ecosystem functions on Africa's largest mountain, Mount Kilimanjaro (Tanzania). We find that increasing land-use intensity causes larger losses of plant and animal species richness in the arid lowlands than in humid submontane and montane zones. Increases in land-use intensity are associated with significant changes in the composition of plant, animal and microorganism communities; stronger modifications of plant and animal communities occur in arid and humid ecosystems, respectively. Temperature, precipitation and land use jointly modulate soil properties, nutrient turnover, greenhouse gas emissions, plant biomass and productivity, as well as animal interactions. Our data suggest that the response of ecosystem functions to land-use intensity depends strongly on climate; more-severe changes in ecosystem functioning occur in the arid lowlands and the cold montane zone. Interactions between climate and land use explained-on average-54% of the variation in species richness, species composition and ecosystem functions, whereas only 30% of variation was related to single drivers. Our study reveals that climate can modulate the effects of land use on biodiversity and ecosystem functioning, and points to a lowered resistance of ecosystems in climatically challenging environments to ongoing land-use changes in tropical mountainous regions.

Many experiments have shown that biodiversity enhances ecosystem functioning. However, we have little understanding of how environmental heterogeneity shapes the effect of diversity on ecosystem functioning and to what extent this diversity effect is mediated by variation in species richness or species turnover. This knowledge is crucial to scaling up the results of experiments from local to regional scales. Here we quantify the diversity effect and its components-that is, the contributions of variation in species richness and species turnover-for 22 ecosystem functions of microorganisms, plants and animals across 13 major ecosystem types on Mt Kilimanjaro, Tanzania. Environmental heterogeneity across ecosystem types on average increased the diversity effect from explaining 49% to 72% of the variation in ecosystem functions. In contrast to our expectation, the diversity effect was more strongly mediated by variation in species richness than by species turnover. Our findings reveal that environmental heterogeneity strengthens the relationship between biodiversity and ecosystem functioning and that species richness is a stronger driver of ecosystem functioning than species turnover. Based on a broad range of taxa and ecosystem functions in a non-experimental system, these results are in line with predictions from biodiversity experiments and emphasize that conserving biodiversity is essential for maintaining ecosystem functioning.

Bionanoparticles based on filamentous phages or flexuous viruses are interesting candidates for meeting the challenges of tailoring biomineralization in hydrogel-based bone tissue substitutes. We hypothesized that hydroxyapatite crystal nucleation and matrix mineralization can be significantly increased by mineralization-inducing (MIP) and integrin binding motif (RGD) peptides presented on biomimetic nanoparticles. In this study, Potato virus X (PVX), a flexible rod-shaped plant virus was genetically engineered to present these functional peptides on its particle surface. Recombinant PVX-MIP/RGD particles were isolated from infected Nicotiana benthamiana plants and characterized by western blot, SEM, TEM, and TPLSM in MSC cultures. The presence of RGD was proven by cell attachment, spreading, and vinculin cluster analysis, and MIP by in vitro mineralization and osteogenic differentiation assays. Thus the tailored surface of genetically engineered PVX forms fibril-like nanostructures which enables enhanced focal adhesion-dependent cell adhesion, and matrix mineralization verified by Alizarin. Hydroxyapatite crystal nucleation is supported on recombinant PVX particles leading to a biomimetic network and bundle-like structures similar to mineralized collagen fibrils. In conclusion, the recombinant flexuous PVX nanoparticles exhibit properties with great potential for bone tissue substitutes. Statement of Significance A suitable biomaterial for tissue engineering should be able to mimic the endogenous extracellular matrix by presenting biochemical and biophysical cues. Novel hydrogel-based materials seek to meet the criteria of cytocompatibility, biodegradability, printability, and crosslinkability under mild conditions. However, a majority of existing hydrogels lack cell-interactive motifs, which are crucial to modulate cellular responses. The incorporation of the plant virus PVX to the hydrogel could improve functions like integrin-binding and mineralization due to peptide-presentation on the particle surface. The tailored surface of genetically engineered PVX forms fibril-like nanostructures which enables enhanced focal adhesion-dependent cell adhesion and matrix mineralization and offers great potential for the development of new hydrogel compositions for bone tissue substitutes.

Aim: Temperature, food resources and top‐down regulation by antagonists are considered as major drivers of insect diversity, but their relative importance is poorly understood. Here, we used cavity‐nesting communities of bees, wasps and their antagonists to reveal the role of temperature, food resources, parasitism rate and land use as drivers of species richness at different trophic levels along a broad elevational gradient. Location: Mt. Kilimanjaro, Tanzania. Taxon: Cavity‐nesting Hymenoptera (Hymenoptera: Apidae, Colletidae, Megachilidae, Crabronidae, Sphecidae, Pompilidae, Vespidae). Methods: We established trap nests on 25 study sites that were distributed over similar large distances in terms of elevation along an elevational gradient from 866 to 1788 m a.s.l., including both natural and disturbed habitats. We quantified species richness and abundance of bees, wasps and antagonists, parasitism rates and flower or arthropod food resources. Data were analysed with generalized linear models within a multi‐model inference framework. Results: Elevational species richness patterns changed with trophic level from monotonically declining richness of bees to increasingly humped‐shaped patterns for caterpillar‐hunting wasps, spider‐hunting wasps and antagonists. Parasitism rates generally declined with elevation but were higher for wasps than for bees. Temperature was the most important predictor of both bee and wasp host richness patterns. Antagonist richness patterns were also well predicted by temperature, but in contrast to host richness patterns, additionally by resource abundance and diversity. The conversion of natural habitats through anthropogenic land use, which included biomass removal, agricultural inputs, vegetation structure and percentage of surrounding agricultural habitats, had no significant effects on bee and wasp communities. Main conclusions: Our study underpins the importance of temperature as a main driver of diversity gradients in ectothermic organisms and reveals the increasingly important role of food resources at higher trophic levels. Higher parasitism rates at higher trophic levels and at higher temperatures indicated that the relative importance of bottom‐up and top‐down drivers of species richness change across trophic levels and may respond differently to future climate change.

Nanotechnology is an expanding interdisciplinary field concerning the development and application of nanostructured materials derived from inorganic compounds or organic polymers and peptides. Among these latter materials, proteinaceous plant virus nanoparticles have emerged as a key platform for the introduction of tailored functionalities by genetic engineering and conjugation chemistry. Tobacco mosaic virus and Cowpea mosaic virus have already been developed for bioimaging, vaccination and electronics applications, but the flexible and filamentous Potato virus X (PVX) has received comparatively little attention. The filamentous structure of PVX particles allows them to carry large payloads, which are advantageous for applications such as biomedical imaging in which multi-functional scaffolds with a high aspect ratio are required. In this context, PVX achieves superior tumor homing and retention properties compared to spherical nanoparticles. Because PVX is a protein-based nanoparticle, its unique functional properties are combined with enhanced biocompatibility, making it much more suitable for biomedical applications than synthetic nanomaterials. Moreover, PVX nanoparticles have very low toxicity in vivo, and superior pharmacokinetic profiles. This review focuses on the production of PVX nanoparticles engineered using chemical and/or biological techniques, and describes current and future opportunities and challenges for the application of PVX nanoparticles in medicine, diagnostics, materials science, and biocatalysis.

Species diversity is the variable most commonly studied in recent ecological research. Ecological processes, however, are driven by individuals and affected by their abundances. Understanding the variation in animal abundances along climatic gradients is important for predicting changes in ecosystem processes under global warming. High abundances make arthropods, despite their small body sizes, important actors in food webs, yet abundance distributions of major arthropod taxa along climatic gradients remain poorly documented. We sampled arthropod assemblages in disturbed and undisturbed vegetation types along an elevational gradient of 860–4550 m asl on the southern slopes of Mt. Kilimanjaro, Tanzania. In our analysis, we focused on 13 taxa of arthropods that represented three major functional groups: predators, herbivores, and decomposers. Abundance patterns were unimodal for most of the taxa and functional groups, including decomposer arthropods, and most of them peaked at low elevations in lower montane forest. When we assigned beetles to functional groups, however, decomposer beetle abundances declined almost linearly, and abundances of predator beetles (ca. 2400 m asl) and herbivore beetles (ca. 3000 m asl, undisturbed vegetation) peaked at higher elevations and exhibited unimodal patterns. Temperature, not primary productivity, was the best predictor of abundance for most of the taxa and groups. Disturbance was only of minor importance. Our results revealed different trends in the response of arthropod abundance along the elevational gradient that depended on the level of taxonomic and functional resolution. This highlights the need for more comparisons of different taxa along the same climatic gradients.

Agriculture and the exploitation of natural resources have transformed tropical mountain ecosystems across the world, and the consequences of these transformations for biodiversity and ecosystem functioning are largely unknown

BioMed research international 2018, 9328671 (2018). doi:10.1155/2018/9328671, Published by Hindawi, New York [u.a.]

Plant virus nanoparticles are often used to display functional amino acids or small peptides, thus serving as building blocks in application areas as diverse as nanoelectronics, bioimaging, vaccination, drug delivery, and bone differentiation. This is most easily achieved by expressing coat protein fusions, but the assembly of the corresponding virus particles can be hampered by factors such as the fusion protein size, amino acid composition, and post-translational modifications. Size constraints can be overcome by using the Foot and mouth disease virus 2A sequence, but the compositional limitations cannot be avoided without the introduction of time-consuming chemical modifications. SpyTag/SpyCatcher technology is used in the present study to covalently attach the Trichoderma reesei endoglucanase Cel12A to Potato virus X (PVX) nanoparticles. The formation of PVX particles is confirmed by western blot, and the ability of the particles to display Cel12A is demonstrated by enzyme-linked immunosorbent assays and transmission electron microscopy. Enzymatic assays show optimal reaction conditions of 50 °C and pH 6.5, and an increased substrate conversion rate compared to free enzymes. It is concluded that PVX displaying the SpyTag can serve as new scaffold for protein display, most notably for proteins with post-translational modifications.

Aim We used the extensive climatic and land-use gradient on Mt Kilimanjaro, Tanzania, to study large-scale variation of nutrient use in ground-foraging ant communities. In particular, we tested the hypothesis that recruitment of ants to six different nutrients would vary with elevation and between land-use regimes. We also tested whether the nutrient space (number and evenness of nutrients) used by ants decreases as species richness declines with elevation, a pattern expected because of complementarity in nutritional intake of species. Location Mt Kilimanjaro, Tanzania. Methods Standardized bait experiments with six nutrient treatments [carbohydrates (CHO), amino acid, CHO–amino acid mix, NaCl, H2O and lipids] were performed at a total of 48 study sites in natural and managed ecosystems along an elevational gradient from 860 to 4390 m a.s.l. We used generalized linear models, information theory-based model inference and null model analyses to test hypotheses. Results The species richness of ant communities declined with elevation in natural ecosystems but peaked at mid-elevations in managed ecosystems. We found that the use of four nutrients (NaCl, CHO, H2O and lipids) varied with elevation and, in the case of NaCl and H2O, with land use. Use of H2O and CHO decreased with elevation, while lipid use increased. NaCl use increased with elevation in natural ecosystems but decreased in managed ecosystems. The nutrient space exploited by ant communities increased with ant species richness in natural ecosystems but decreased slightly in managed ecosystems. The difference could be because there are more trophic generalists in managed ecosystems and more specialists with complementary foraging niches in natural ecosystems. Main conclusions Ant communities in different environments appear to be limited by different types and numbers of nutrients. This spatial heterogeneity in nutritional ecology is probably determined by both the environmental availability of nutrients and the functional composition of ant communities.

Ecologists have long recognized the important role of canopy heterogeneity in structuring the diversity of animal communities. However, studies directly linking variation in the three-dimensional structure of forests to variation in biodiversity are still rare. For canopy arthropods representing a dominant component of forest biodiversity in montane spruce forests of Europe, we used publicly available airborne LiDAR measurements to test the premises of two existing hypotheses that resource concentration and habitat heterogeneity are potential drivers of faunal diversity at both the tree scale and stand scale. We sampled 391 arthropod species from the canopies of 60 trees; coverage-based rarefaction revealed high completeness of faunal sampling (93.7%). When we controlled for elevation and broadleaf tree cover, we found strong (tree and stand scale) context dependence in the response of arthropod diversity to variation in vegetation structure. Arthropod diversity increased with increasing canopy density at the tree scale and was positively associated only with vegetation heterogeneity at the tree scale, but decreased with increasing canopy density at the stand scale. These trends held across all levels of biological response from total richness to diversity measures to richness of different guilds. Our results showed that different components of vegetation structural complexity drive canopy arthropod biodiversity at different spatial scales. Highest canopy arthropod diversity can be expected in spruce forests with relatively open stands containing individual trees with dense and long crowns. Thus, LiDAR opens new avenues for testing ecological hypotheses and for forest-growth models to be linked with the canopy diversity of forests.

Norway Spruce is the economically most important tree species in Europe and has been cultivated in plantations on a large-scale at low elevations, far outside its natural range. In the Bohemian Forest, it naturally occurs in pure stands above 1150 m a.s.l. and as a mixed tree species from 650 to 1150 m a.s.l. An understanding of natural distributions and the diversity along temperature gradients at various elevations is important for conservation, pest management, and predictions of future species assemblages by global warming. Here we investigated the species richness of canopy arthropods in spruce trees along a gradient from 300 to 1300 m a.s.l. using flight-interception traps. We analyzed species richness by combining diversity partitioning with a moving window approach after standardizing sample size per plot. Total richness decreased linearly as the elevation increased, which reflected declining temperatures and a declining regional species pool. Phytophages (herbivores excluding xylophages) were the most influenced. Richness did not peak at the transition zones of the three ecological elevation zones, neither for all species, nor for any of the separate functional groups. However, the proportion of both beetle and true bug spruce specialists significantly increased with elevation and actually doubled in richness above 1000 m a.s.l., where spruce is naturally dominating. Our results indicate that even planted spruce trees at lower elevations maintain high levels of species richness. Further climate warming will promote overall species richness, especially of phytophages, at all elevations. However, spruce specialists may be seriously threatened by global warming.

Biotechnology for biofuels 5, 63 (2012). doi:10.1186/1754-6834-5-63, Published by BioMed Central, London