The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points.

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Minimal information for studies of extracellular vesicles 2018 (MISEV2018) : a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

Foreign body reaction to biomaterials.

5.1. Detection Formats 475 5.2. Food Quality and Safety Analysis 477 5.2.1. Pathogens 477 5.2.2. Toxins 479 5.2.3. Veterinary Drugs 479 5.2.4. Vitamins 480 5.2.5. Hormones 480 5.2.6. Diagnostic Antibodies 480 5.2.7. Allergens 481 5.2.8. Proteins 481 5.2.9. Chemical Contaminants 481 5.3. Medical Diagnostics 481 5.3.1. Cancer Markers 481 5.3.2. Antibodies against Viral Pathogens 482 5.3.3. Drugs and Drug-Induced Antibodies 483 5.3.4. Hormones 483 5.3.5. Allergy Markers 483 5.3.6. Heart Attack Markers 484 5.3.7. Other Molecular Biomarkers 484 5.4. Environmental Monitoring 484 5.4.1. Pesticides 484 5.4.2. 2,4,6-Trinitrotoluene (TNT) 485 5.4.3. Aromatic Hydrocarbons 485 5.4.4. Heavy Metals 485 5.4.5. Phenols 485 5.4.6. Polychlorinated Biphenyls 487 5.4.7. Dioxins 487 5.5. Summary 488 6. Conclusions 489 7. Abbreviations 489 8. Acknowledgment 489 9. References 489

Surface Plasmon Resonance Sensors for Detection of Chemical and Biological Species

Bacterial biofilms in nature and disease.

Principles and potential of the anaerobic digestion of waste-activated sludge

Inhibition of bacterial adhesion and biofilm formation on zwitterionic surfaces.

Zwitterionic carboxybetaine polymer surfaces and their resistance to long-term biofilm formation

Efficacy of silver-coated poly(ethylene terephthalate) to prevent bacterial attachment and subsequent infection was quantified in vitro, in both batch- and flowing-fluid experiments. Kinetic analysis of batch suspended cell cultures of Staphylococcus epidermidis (SE), at various growth-limiting nutrient concentrations, in the absence of any fabric, indicated a maximum culture growth rate constant μmax = 0.78 ± 0.02 h−1. Batch experiments for Control fabric samples indicated that SE cultures exhibited about the same suspended cell growth rate (0.72 ± 0.02 h−1) as observed in batch suspended cultures without fabric. Suspended SE cultures in the presence of silver-coated fabric grew at a considerably lower rate, 0.15 ± 0.01 h−1, indicating the inhibitory effect of Ag+2 ion released from the fabric. Growth rates of suspended SE cultures were 5–6 times higher in the fluid phase in contact with the Control fabric compared to cultures exposed to silver-coated fabric. Maximum suspended cell concentrations attained at time = 24 h were 1–2 orders of magnitude higher for Control fabrics vs. silver-coated fabric. In all batch colonization experiments, both live and dead SE bacterial cells accumulate on the surfaces of both silver-coated and Control fabrics. Adherent viable SE cells accumulated to 1–2 orders of magnitude more (∼5 × 10+8 cells/cm2) on Control fabric than SE cells on the silver-coated fabric (∼1.1 × 10+6 cells/cm2), respectively. Between 70–95% SE cells on the Control fabric were viable, while on the silver-coated fabric samples, at 24 h, viable cells were less than 10% of the adherent community (i.e., greater than 90% nonviable cells). In flow cell colonization experiments, SE cells accumulated on Control fabric to a maximum adherent cell concentration of 6 × 10+7 − 8 × 10+7 cells/cm2 by 24 h with the proportion of viable cells remaining relatively constant at 76% throughout an experiment. Both noninvasive microscopic enumeration and destructive assays gave the same results for adherent cell numbers. Using silver-coated fabric, total cells numbers (live + dead) reached a level of ∼1.1 × 10+7 − 3.0 × 10+7 cells/cm2 after about 6 h and remained constant. However, while the proportion of viable cells initially on the surface was 63–75%, this fraction dropped continuously during each experiment to less than 6% viable cells at 24 h. Regardless of the criteria, the number of viable or nonviable cells attached to silver-coated fabric were significantly lower than on Control fabric. © 2000 John Wiley & Sons, Inc. Biomed Mater Res (Appl Biomater) 53: 621–631, 2000

Efficacy of silver‐coated fabric to prevent bacterial colonization and subsequent device‐based biofilm formation

Fouling biofilm development was monitored in a completely mixed tubular recycle reactor. A unique sampling system allowed direct (brightfield, epifluorescence, and scanning electron photomicroscopy...

Observations of fouling biofilm formation.

This article focuses on one of the major failure routes of implanted medical devices, the foreign body reaction (FBR)--that is, the phagocytic attack and encapsulation by the body of the so-called "biocompatible" biomaterials comprising the devices. We then review strategies currently under development that might lead to biomaterial constructs that will harmoniously heal and integrate into the body. We discuss in detail emerging strategies to inhibit the FBR by engineering biomaterials that elicit more biologically pertinent responses.

James D. Bryers

Papers

Inhibition of bacterial adhesion and biofilm formation on zwitterionic surfaces.

Zwitterionic carboxybetaine polymer surfaces and their resistance to long-term biofilm formation

Efficacy of silver‐coated fabric to prevent bacterial colonization and subsequent device‐based biofilm formation

Observations of fouling biofilm formation.

Engineering biomaterials to integrate and heal: The biocompatibility paradigm shifts