Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches

Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly

Hiker impacts on aquatic invertebrate assemblages in the North Fork of the Virgin River in Zion National Park, Utah

The effects of in-stream hiking on aquatic invertebrate assemblages were examined in the North Fork of the Virgin River in Zion National Park, Utah. A localized effects study was used to investigate hiker impacts on aquatic invertebrate drift at three sites in concentrated use areas. A broad-scale study was used to determine how anthropogenic disturbance affected benthic invertebrate assemblages and their resources in the context of natural disturbance (flash flooding) and environmental variation at 11 sites of varying visitor use levels. Total aquatic invertebrate drift densities increased with increasing hiker numbers to a threshold level when approximately 40 hikers were hiking in the stream during a 30-minute period. At a broad scale, abundance of the most common taxon (Baetis) was lower at high use sites as compared to low use sites. No differences in genera richness, total abundance, or abundance of eight other common taxa were observed among use levels. Flow events appeared to play a larger role in shaping aquatic invertebrate communities than did hikers. A flow increase caused by a side-canyon flash flood increased aquatic invertebrate abundance at three sites in July 2006, while a flash flood with a six-year return interval reduced total aquatic invertebrate abundances at all sites in August 2006. These results suggest that, while visitor use in Zion National Park affects aquatic invertebrates at a localized scale, large-scale natural disturbance can ameliorate these impacts

VEGFA Family Isoforms Regulate Spermatogonial Stem Cell Homeostasis \u3ci\u3ein Vivo\u3c/i\u3e

The objective of the present study was to investigate vascular endothelial growth factor A (VEGFA) isoform regulation of cell fate decisions of spermatogonial stem cells (SSC) in vivo. The expression pattern and cell-specific distribution of VEGF isoforms, receptors, and coreceptors during testis development postnatal d 1–180 suggest a nonvascular function for VEGF regulation of early germ cell homeostasis. Populations of undifferentiated spermatogonia present shortly after birth were positive for VEGF receptor activation as demonstrated by immunohistochemical analysis. Thus, we hypothesized that proangiogenic isoforms of VEGF (VEGFA164) stimulate SSC self-renewal, whereas antiangiogenic isoforms of VEGF (VEGFA165b) induce differentiation of SSC. To test this hypothesis, we used transplantation to assay the stem cell activity of SSC obtained from neonatal mice treated daily from postnatal d 3–5 with 1) vehicle, 2) VEGFA164, 3) VEGFA165b, 4) IgG control, 5) anti-VEGFA164, and 6) anti-VEGFA165b. SSC transplantation analysis demonstrated that VEGFA164 supports self-renewal, whereas VEGFA165b stimulates differentiation of mouse SSC in vivo. Gene expression analysis of SSC-associated factors and morphometric analysis of germ cell populations confirmed the effects of treatment on modulating the biological activity of SSC. These findings indicate a nonvascular role for VEGF in testis development and suggest that a delicate balance between VEGFA164 and VEGFA165b isoforms orchestrates the cell fate decisions of SSC. Future in vivo and in vitro experimentation will focus on elucidating the mechanisms by which VEGFA isoforms regulate SSC homeostasis

VEGFA Family Isoforms Regulate Spermatogonial Stem Cell Homeostasis in Vivo

The objective of the present study was to investigate vascular endothelial growth factor A (VEGFA) isoform regulation of cell fate decisions of spermatogonial stem cells (SSC) in vivo. The expression pattern and cell-specific distribution of VEGF isoforms, receptors, and coreceptors during testis development postnatal d 1–180 suggest a nonvascular function for VEGF regulation of early germ cell homeostasis. Populations of undifferentiated spermatogonia present shortly after birth were positive for VEGF receptor activation as demonstrated by immunohistochemical analysis. Thus, we hypothesized that proangiogenic isoforms of VEGF (VEGFA164) stimulate SSC self-renewal, whereas antiangiogenic isoforms of VEGF (VEGFA165b) induce differentiation of SSC. To test this hypothesis, we used transplantation to assay the stem cell activity of SSC obtained from neonatal mice treated daily from postnatal d 3–5 with 1) vehicle, 2) VEGFA164, 3) VEGFA165b, 4) IgG control, 5) anti-VEGFA164, and 6) anti-VEGFA165b. SSC transplantation analysis demonstrated that VEGFA164 supports self-renewal, whereas VEGFA165b stimulates differentiation of mouse SSC in vivo. Gene expression analysis of SSC-associated factors and morphometric analysis of germ cell populations confirmed the effects of treatment on modulating the biological activity of SSC. These findings indicate a nonvascular role for VEGF in testis development and suggest that a delicate balance between VEGFA164 and VEGFA165b isoforms orchestrates the cell fate decisions of SSC. Future in vivo and in vitro experimentation will focus on elucidating the mechanisms by which VEGFA isoforms regulate SSC homeostasis

Ordination based on non-metric multidimensional scaling (nMDS) analysis of chironomid communities from the three lakes and lake zones (black fill and NS = nearshore, no fill and DP = deep zone) in this study.

<p>Two axes were chosen to best display the data (stress = 0.20).</p

Pairwise comparisons of chironomid communities from the different habitats in Lake Tahoe, Crater Lake, and Lake Hövsgöl.

<p>Distance R-statistics and <i>p-</i>values given from ANOSIM. The closer R is to 1 the greater the distance or dissimilarity between two communities being compared.</p><p>Pairwise comparisons of chironomid communities from the different habitats in Lake Tahoe, Crater Lake, and Lake Hövsgöl.</p

Map of Lake Tahoe, USA, Crater Lake, USA and Lake Hövsgöl, Mongolia.

<p>Solid circles indicate sampling locations in 2008 and 2009 for Lake Tahoe, 2009 for Crater Lake, and 1995–1997 for Lake Hövsgöl.</p

Physical and geographic variables for the three study lakes.

<p>Physical and geographic variables for the three study lakes.</p