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Background and Objectives: The main drawback of lipofilling is fat transplant volume loss, which makes long-term results unreliable. This study’s aim was to assess the influence of an adipose-derived stromal vascular fraction (SVF) on volume retention in large-volume fat grafts. Materials and Methods: A murine model was used for the in vivo evaluation of fat-graft volume changes over 6 months. We used 28 immunocompromised nude NU(NCr)-Foxn1nu mice and human fat tissue as a liposuction by-product. Part of the fat tissue was used for SVF preparation. We created a fat transplant without SVF (SVF-) and with SVF (SVF+) groups. Large-volume grafts were injected above the sacrum and scapula in the same animal. Volume loss was evaluated using three-dimensional optical scanning at 14 days (T1), 3 months (T2), and 6 months (T3) after transplantation. Scans were processed with Artec Studio software to obtain stereolithography files. The volumes were calculated in RapidForm software 2006. Results: The highest volume loss was observed above the scapula at T3 (SVF- 85%; SVF+ 75%). There was a significant difference in volume between SVF-/SVF+ for grafts above the sacrum at T2, with lower loss in SVF+, and the significance became stronger at T3. The difference in volume loss was also significant above the scapula between SVF-/SVF+ at T3. Conclusions: Although we found a beneficial effect of SVF on the long-term survival of large-volume fat tissue transplants, volume loss due to other contributing factors was high.

Plant-derived nanovesicles (NVs) have attracted interest due to their anti-inflammatory, anticancer and antioxidative properties and their efficient uptake by human intestinal epithelial cells. Previously we showed that tomato (Solanum lycopersicum L.) fruit is one of the interesting plant resources from which NVs can be obtained at a high yield. In the course of the isolation of NVs from different batches of tomatoes, using the established differential ultracentrifugation or size-exclusion chromatography methods, we occasionally observed the co-isolation of viral particles. Density gradient ultracentrifugation (gUC), using sucrose or iodixanol gradient materials, turned out to be efficient in the separation of NVs from the viral particles. We applied cryogenic transmission electron microscopy (cryo-TEM), scanning electron microscopy (SEM) for the morphological assessment and LC–MS/MS-based proteomics for the protein identification of the gradient fractions. Cryo-TEM showed that a low-density gUC fraction was enriched in membrane-enclosed NVs, while the high-density fractions were rich in rod-shaped objects. Mass spectrometry–based proteomic analysis identified capsid proteins of tomato brown rugose fruit virus, tomato mosaic virus and tomato mottle mosaic virus. In another batch of tomatoes, we isolated tomato spotted wilt virus, potato virus Y and southern tomato virus in the vesicle sample. Our results show the frequent co-isolation of plant viruses with NVs and the utility of the combination of cryo-TEM, SEM and proteomics in the detection of possible viral contamination.

Despite their high potential, most of the clinically approved iron oxide (IO)-based contrast agents for magnetic resonance imaging (MRI) have been withdrawn from the market either due to safety issues or lack of sales. To address this challenge, erythrocyte membranes have been used to prepare IO-based T2 contrast agents with superior MRI properties and higher safety margin. A simple formulation procedure has been proposed, and the nanostructures’ morphology and physicochemical properties have been evaluated. We compared their performance in terms of contrast ability in MRI to the more clinically established magneto-liposomes and non-encapsulated nanoparticles (NPs). The encapsulation of 5-nm iron oxide nanoparticles (IO NPs) in the liposomes and erythrocyte membrane vesicles (EMVs) led to a significant improvement in their r2 relaxivity. r2 values increased to r2 = 188 ± 2 mM−1s−1 for magneto-liposomes and r2 = 269 ± 3 mM−1s−1 for magneto-erythrocyte membranes, compared to “free” IO NPs with (r2 = 12 ± 1 mM−1 s−1), measured at a 9.4 T MRI scanner. The superiority of magneto-erythrocyte membranes in terms of MRI contrast efficacy is clearly shown on T2-weighted MR images. Our study revealed the hemocompatibility of the developed contrast agents in the MRI-relevant concentration range.