Exosomes/EVs: BIOXOME: A NATURAL LIPOSOME MIMETIC AS DRUG DELIVERY SYSTEM

Background & Aim: Liposomes are spherical-shaped vesicles composed of one or more lipid bilayers. The ability of liposomes to encapsulate hydro- or lipophilic drugs allowed these vesicles to become a useful drug delivery system. Natural cell membranes, such as Bioxome, have newly emerged as new source of materials for molecular delivery systems. Bioxome are biocompatible and GMP-compliant liposome-like membrane that can be produced from more than 200 cell types. Bioxome self-assemble, with in-process self-loading capacity and can be loaded with a variety of therapeutic compounds. Once close to the target tissue, Bioxome naturally fuse with the cell membrane and release the inner compound. Orgenesis is interested in evaluating the potential of Bioxome as new drug delivery system for treatment of several diseases, including skin repair, local tumour or COVID19. Methods, Results & Conclusion(s): Bioxome were obtained from adipose- derived Mesenchymal Stem Cells, with a process of organic- solvent lipid extraction, followed by lyophilization and sonication assemblage. During the sonication process, Bioxome were charged or not with several cargos. Size distribution of empty Bioxome was detected by Particle Size Analyzer (NanoSight). Electron Microscopy (EM) was performed to assess Bioxome morphology. Lipid content was evaluated by electrospray ionization system. Dose response in vitro test on human lung fibroblasts treated or not with Bioxome encapsulating a specific cargo (API) against COVID19 were performed. NanoSight analysis showed that nanoparticle size in Bioxome samples ranged between 170+/-50 nm, with a concentration ranging between 109-1010+/-106 particles/mL. EM clearly showed the double phospholipid layers that composes the Bioxome. Stability study demonstrated that Bioxome are stable in size and concentration up to 90 days at +4Cdegree or even at RT. No change in size between encapsulated Bioxome with small size (~340 Da) cargo vs empty Bioxome was observed up to 30 days storage. Lipidomic analysis approach revealed that the yield of lipids and their composition are satisfactory for a therapeutic product using Bioxome. Lastly, in the in vitro model of COVID19, Bioxome encapsulating API effectively saved cells from death (20x vs untreated cells) and at lower doses of API than these of non-encapsulated cargo (0.005 microM vs 0.1 microM). Bioxome seems to be an excellent candidate for liposome mimetic tool as drug delivery system for targeting specific organs and diseases treatment.Copyright © 2023 International Society for Cell & Gene Therapy

Co-exposure to urban particulate matter and aircraft noise adversely impacts the cerebro-pulmonary-cardiovascular axis in mice

Worldwide, up to 8.8 million excess deaths/year have been attributed to air pollution, mainly due to the exposure to fine particulate matter (PM). Traffic-related noise is an additional contributor to global mortality and morbidity. Both health risk factors substantially contribute to cardiovascular, metabolic and neuropsychiatric sequelae. Studies on the combined exposure are rare and urgently needed because of frequent co-occurrence of both risk factors in urban and industrial settings. To study the synergistic effects of PM and noise, we used an exposure system equipped with aerosol generator and loud-speakers, where C57BL/6 mice were acutely exposed for 3d to either ambient PM (NIST particles) and/or noise (aircraft landing and take-off events). The combination of both stressors caused endothelial dysfunction, increased blood pressure, oxidative stress and inflammation. An additive impairment of endothelial function was observed in isolated aortic rings and even more pronounced in cerebral and retinal arterioles. The increase in oxidative stress and inflammation markers together with RNA sequencing data indicate that noise particularly affects the brain and PM particularly affects the lungs. Noise also increased levels of circulating stress hormones adrenaline and noradrenaline, while PM increased levels of circulating cytokines CD68 and MCP-1. The combination of both stressors has additive adverse effects on the cardiovascular system that are based on PM-induced systemic inflammation and noise-triggered stress hormone signaling. We demonstrate an additive upregulation of ACE-2 in the lung, suggesting that there may be an increased vulnerability to COVID-19 infection. The data warrant further mechanistic studies to characterize the propagation of primary target tissue damage (lung, brain) to remote organs such as aorta and heart by combined noise and PM exposure.Copyright © 2023

Vulnerability of human preimplantation embryos to SARSCoV-2 infection

Presence of SARS-CoV-2, the virus responsible for COVID-19, has been reported in numerous organs and tissues of infected patients, including the reproductive system. The effects of COVID-19 on human reproduction remain poorly understood. While cases of intrauterine transmission between expectant mother and fetus have been documented, the impact of SARS-CoV-2 infection on early embryogenesis and establishment of a pregnancy are not known. This prompted us to ask if SARS-CoV-2 can infect embryos, since such an event could impact embryo viability and affect a subsequent pregnancy. We used a three-pronged approach to investigate this possibility: 1) Using RNA-seq and immunofluorescence, we learned that ACE2 and TMPRSS2, two factors required on target cells for SARS-CoV-2 entry, are coexpressed in cells of the trophectoderm in blastocyst-stage preimplantation embryos;2) Using fluorescent reporter virions pseudotyped with Spike (S) glycoprotein from SARS-CoV-2, we observed robust infection of trophectoderm cells, and this permissiveness could be attenuated with blocking antibodies targeting S or ACE2;and 3) Exposing human blastocysts to live, fully infectious SARS-CoV-2, we detected cases of infection that compromised embryo health. Therefore, we identify a new human target tissue for SARS-CoV-2 with potential medical implications for reproductive health during the COVID-19 pandemic and its aftermath.

Intracellular Cytokine Profiling by High-Dimensional Flow Cytometry Demonstrates Highly Augmented Cytotoxicity and Overly Activated NK cells in COVID-19 Patients

Background: COVID-19 pandemic has caused more than 4.7 million deaths worldwide to date and still continues globally unabated. Numerous studies have linked the mortality in COVID-19 to aggressive immune response and cytokine storm. However, little is known about the cytokine profiles of individual immune cells that are directly involved in tissue damage. Here we investigate intracellular cytokines in individual T and NK cells of COVID-19 patients. Design: We studied 50 blood samples from 22 COVID-19 patients, 4 with mild, 6 moderate and 12 severe disease. There were 6 healthy controls. We performed high-dimensional 30-color spectral flow cytometry to characterize the immune cell subsets. For cytokine study, cells were stimulated for 6 hours, and stained for surface antigens and intracellular cytokines (IL1b, IL2, IL4, IL6, IL8, IL10, IL12, IL17a, IL21, INFg, GnzB, TNFa, and GMCSF). Data ware acquired on FACSymphony 50-parameter analyzer and analysis performed using FlowJo. Results: Our studies revealed significant differences in lymphocyte cytokine profiles between COVID+ and healthy controls (Fig 1). CD4+ and CD8+ T-cells exhibited increased percentages of IL2+ and IFNg+ cells, indicating a shift towards Th1 reaction. Granzyme B is highly upregulated in all T and NK cell subsets, demonstrating highly armed cytotoxic cells in COVID patients. The most prominent changes were noted in NK cells, 7 cytokines were highly expressed, most are proinflammatory cytokines. Of particular interest are IL-21 and GMCSF, both are known to play important roles in inflammatory cell recruitment, activation and renewal, which can lead to augmented tissue inflammation and injury. These changes were already evident in patients with mild disease, but there is heightened cytokine production in severe cases. Conclusions: Using high-dimensional flow cytometry we demonstrated for the first time significantly increased production of multiple proinflammatory cytokines and cytotoxic molecules in individual T and NK cells of COVID-19 patients. NK cells are most drastically activated. It is conceivable that when recruited to the target tissue such as lung, these highly primed cells will play a major role in tissue injury and ultimately organ failure via their direct cytotoxicity and cytokine secretion. This is consistent with previous reports of increased NK cells in the COVID lungs. Analysis of NK cell cytokine profiles may serve to predict disease progression, and reveal new targets for immune-therapy for severe COVID patients. (Table Presented).

Review of etiopathogenesis and Early diagnosis of Mucormycosis

Mucormycosis refers to invasive fungal disease whose causative organism are saprophytic fungi. Recently there has been an outbreak of mucor in post covid cases. It is a fatal disease until properly intervened.The literature regarding mucormycosis is scarce. There is urgent need to understand the aetiopathogeneis and clinical features of mucormycosis. This article helps to comprehensively understand the etiopathogenesis in patients having mucormycosis. This narrative review is an attempt to comprehend aetiopathogeneis and early diagnostic features in mucormycosis.Literature on various aspects of mucormycosis was collected from various search engines like pubmed, Google scholar. Various phrases used were mucormycosis, etiology, pathogenesis diagnosis.Various risk factors associated with this disease are use of corticosteroids, metabolic acidosis, diabetes mellitus, burns organ transplants, malignancies and various haematological disorders. Nososcomial infections mostly due to non sterility is proving to be a kajor risk factor has in mucormycosis. Immunocompromised patients are at a greater risk for acquiring infection however few reports of mucormycosis in immunocompetent patients have been published. Angioinvasion leads to thrombosis followed by necrosis of the tissue hampering drug delivery to the target tissue. Angio invasion is the single most important factor explaining pathology.Early diagnosis and intervention is the only key way to treat mucormycosis patients as early diagnosis will help in early treatment and that ultimately decrease angioinvasion and less extensive surgeries. Traditional cultural method can be used for early diagnosis but it has a higher possibility false negative results. Few clinical signs that may help in early diagnosis can be necrotic eschars in various mucosal surfaces, pleuritic pain, ophthalmic symptoms are important markers. Though these clinical signs help, they may present after long time. So imaging techniques like CT scan and MRI have a really important part in early diagnosis. MRI is more sensitive for tthe diagnosis of invasive fungal sinusitis than CT and it also gives less false negative results.