Extracellular vesicles (EVs) are secreted from almost all human cells and mediate intercellular communication by transferring heterogeneous molecules (i.e., DNA, RNAs, proteins, and lipids). In this way, EVs participate in various biological processes, including immune responses. Viruses can hijack EV biogenesis systems for their dissemination, while EVs from infected cells can transfer viral proteins to uninfected cells and to immune cells in order to mask the infection or to trigger a response. Several studies have highlighted the role of native or engineered EVs in the induction of B cell and CD8(+) T cell reactions against viral proteins, strongly suggesting these antigen-presenting EVs as a novel strategy for vaccine design, including the emerging COVID-19. EV-based vaccines overcome some limitations of conventional vaccines and introduce novel unique characteristics useful in vaccine design, including higher bio-safety and efficiency as antigen-presenting systems and as adjuvants. Here, we review the state-of-the-art for antiviral EV-based vaccines, including the ongoing projects of some biotech companies in the development of EV-based vaccines for SARS-CoV-2. Finally, we discuss the limits for further development of this promising class of therapeutic agents.

Most crimes committed are against property (theft, robbery) and against the person (bodily harm, sexual violence, murder), but very often the perpetrators are not punished, since traces with analyzable biological material that could identify them cannot be found. In Italy in the year 2000, 86.95% of crimes remained unpunished, a percentage that increases to 96.12% in the case of theft (1). Apart from the few cases in which crimes are planned and precautions are taken to prevent leaving any biological traces at the scene, in most crimes of this type, i.e., theft, robbery, bodily harm, etc., criminals do not wear gloves or other devices, and fingerprints are the only evidence available. The literature contains preliminary studies or case histories on the possibility of recovering DNA from fingerprints left on the skin or on rope, cord, wire, etc., used for strangling, on gloves, knives, solid parts of cars and other objects, and on the interference by substances used to highlight fingerprints during later genetic analysis (2,3). These works report isolated experiments dictated by the need to resolve definite cases. Systematic studies of various factors influencing the success of analysis, such as recovery techniques, interference by contaminants, i.e., latent fingerprint enhancers, and amplification protocols of low-copynumber (LCN) DNA usually recovered from fingerprints, are in progress (4-9). Systematic studies of the influence of various modes of contact and type of substrate in the success of PCR analysis have not been exhaustively carried out. Lastly, the relevance of contamination by different subjects due to secondary and tertiary transfers affecting the robustness of results and the usability of analytical results in court must all be considered more deeply. The same origin of the DNA found in these skin contact traces and the influences of individual and exogenous factors in the number of cells left with the fingerprint still remain unclear. Therefore, the use of this substrate for genetic identification is a subject of passionate debate in the forensic community, and further contributions are still necessary to highlight the advantages, difficulties and limitations of DNA analysis from fingerprints. This study was carried out with the aims of investigating the amount of DNA recovered from various substrates and the influence on it of individual and exogenous factors, as well as the suitability of DNA recovered from fingerprints for personal identification by DNA microsatellites. The importance of contamination by exogenous DNA transfer and the stochastic effects on analysis from sampling minimal amounts of DNA recovered from fingerprints were also considered. Materials and Methods Collection of Samples The fingerprints from eleven persons working in the laboratory were applied to the following clean substrates: glass, metal (alloy metallic surfaces), and wood (cortex of hard wood). Experiments were carried out without washing the hands and immediately after

Persistent organochlorine pollutants (POPs) are suspected to interfere with hormone activity and the normal homeostasis of spermatogenesis. We investigated the relationships between sperm DNA fragmentation, apoptotic markers identified on ejaculated spermatozoa and POP levels in the blood of 652 adult males (200 Inuits from Greenland, 166 Swedish, 134 Polish and 152 Ukrainian). Serum levels of 2, 2 0 , 4, 4 0 , 5, 5 0 -hexachlorobiphenyl (CB-153), as a proxy of the total POP burden, and of, as a proxy of the total DDT exposure were determined. Sperm DNA fragmentation was measured by using the TUNEL assay, whereas immunofluorescence methods were utilized for detecting proapoptotic (Fas) and anti-apoptotic (Bcl-xL) markers. Both TUNEL assay and apoptotic markers were statistically differed across the four populations. No correlation between neither sperm DNA fragmentation nor apoptotic sperm parameters and the large variations in POPs exposure was observed for the separate study groups. However, considering the European populations taken together, we showed that both %TUNEL positivity and Bcl-xL were related to CB-153 serum levels, whereas our study failed to demonstrate any relations between DDE and %TUNEL positivity and apoptotic sperm biomarkers (Fas and Bcl-xL) in any region or overall regions. These results suggest that CB-153 and related chemicals might alter sperm DNA integrity and Bcl-xL levels in European adult males, but not in the highly exposed Inuit men. Additional issues (genetic background, lifestyle habits and characterization of total xeno-hormonal activities) need to be investigated in order to fully assess the population variations observed.Reproduction (2006) 132 949-958

BackgroundEarly pregnancy loss can be associated with trophoblast insufficiency and coagulation defects. Thrombomodulin is an endothelial-associated anticoagulant protein involved in the control of hemostasis and inflammation at the vascular beds and it's also a cofactor of the protein C anticoagulant pathway.DiscussionWe evaluate the Thrombomodulin expression in placental tissue from spontaneous recurrent miscarriage and voluntary abortion as controls. Thrombomodulin mRNA was determined using real-time quantitative polymerase chain reaction. Reduced expression levels of thrombomodulin were found in recurrent miscarriage group compared to controls (1.82-fold of reduction), that corresponds to a reduction of 45% (from control group Delta CT) of thrombomodulin expression in spontaneous miscarriage group respect the control groups.SummaryWe cannot state at present the exact meaning of a reduced expression of Thrombomodulin in placental tissue. Further studies are needed to elucidate the biological pathway of this important factor in the physiopathology of the trophoblast and in reproductive biology.

The ACE2 receptor is, so far, the best-known host factor for SARS-CoV-2 entry, but another essential element, the TMPRSS2 protease, has recently been identified. Here, we have analysed TMPRSS2 expression data in the lung correlating them with age, sex, diabetes, smoking habits, exposure to pollutant and other stimuli, in order to highlight which factors might alter TMPRSS2 expression, and thus impact the susceptibility to infection and COVID-19 prognosis. Moreover, we reported TMPRSS2 polymorphisms affecting its expression and suggested the ethnic groups more prone to COVID-19. Finally, we also highlighted a gender-specific co-expression between TMPRSS2 and other genes related to SARS-CoV-2 entry, maybe explaining the higher observed susceptibility of infection in men. Our results could be useful in designing potential prevention and treatment strategies regarding the COVID-19.