Oncomatrix: Molecular Composition and Biomechanical Properties of the Extracellular Matrix in Human Tumors

The extracellular matrix is an organized three-dimensional network of protein-based molecules and other macromolecules that provide structural and biochemical support to tissues. Depending on its biochemical and structural properties, the extracellular matrix influences cell adhesion and signal transduction and, in general, can influence cell differentiation and proliferation through specific mechanisms of chemical and mechanical sensing. The development of body tissues during ontogenesis is accompanied by changes not only in cells but also in the composition and properties of the extracellular matrix. Similarly, tumor development in carcinogenesis is accompanied by a continuous change in the properties of the extracellular matrix of tumor cells, called ‘oncomatrix’, as the tumor matures, from the development of the primary focus to the stage of metastasis. In this paper, the characteristics of the composition and properties of the extracellular matrix of tumor tissues are considered, as well as changes to the composition and properties of the matrix during the evolution of the tumor and metastasis. The extracellular matrix patterns of tumor tissues can be used as biomarkers of oncological diseases as well as potential targets for promising anti-tumor therapies.

Microbiota-Induced Radioprotection: A Novel Approach to Enhance Human Radioresistance with In-Situ Genetically Engineered Gut Bacteria

The high sensitivity of living organic forms to space radiation remains the critical issue during spaceflight, to which they will be chronically exposed during months of interplanetary or even decades of interstellar spaceflight. In the human body, all actively dividing and poorly differentiated cells are always close to being damaged by radiological or chemical agents. The chronic exposure to ionizing radiation primarily causes changes in blood counts and intestinal damage such as fibrosis, obliterative vasculitis, changes in the gut microbiota, and atrophy or degeneration of muscle fibers. The project “MISS: Microbiome Induced Space Suit” was presented at the Giant Jamboree of the International Genetically Engineered Machine Competition 2021, with the aim to investigate the ability of the novel microbiota-mediated approach to enhance human resistance to ionizing radiation. The key innovative part of the project was the idea to create a novel radioprotector delivery mechanism based on human gut microbiota with the function of outer membrane vesicles (OMVs) secretion. The project concept proposed the feasibility of genetically modifying the human microbiota in situ through the delivery of genetic constructs to the host’s crypts using silicon nanoparticles with chemically modified surfaces. In this perspective, we discuss the advances in modifying microbiota-mediated secretory activity as a promising approach for radioprotection and as an alternative to hormone therapy and other health conditions that currently require continuous drug administration. Future clinical trials of in situ methods to genetic engineering the crypt microbiota may pave the way for indirect regulation of human cells.

Pitfalls and promises of bile duct alternatives: There is plenty of room in the regenerative surgery

Current abdominal surgery has several approaches for biliary reconstruction. However, the creation of functional and clinically applicable bile duct substitutes still represents an unmet need. In the paper by Miyazawa and colleagues, approaches to the creation of bile duct alternatives were summarized, and the reasons for the lack of development in this area were explained. The history of bile duct surgery since the nineteenth century was also traced, leading to the conclusion that the use of bioabsorbable materials holds promise for the creation of bile duct substitutes in the future. We suggest three ideas that may stimulate progress in the field of bile duct substitute creation. First, a systematic analysis of the causative factors leading to failure or success in the creation of bile duct substitutes may help to develop more effective approaches. Second, the regeneration of a bile duct is delicately balanced between epithelialization and subsequent submucosal maturation within limited time frames, which may be more apparent when using quantitative models to estimate outcomes. Third, the utilization of the organism's endogenous regeneration abilities may enhance the creation of bile duct substitutes. We are convinced that an interdisciplinary approach, including quantitative methods, machine learning, and deep retrospective analysis of the causes that led to success and failure in studies on the creation of bile duct substitutes, holds great value. Additionally, more attention should be directed towards the balance of epithelialization and submucosal maturation rates, as well as induced angiogenesis. These ideas deserve further investigation to pave the way for bile duct restoration with physiologically relevant outcomes.

Pathologically altered articular cartilage attracts intense chondrocyte invasion into the extracellular matrix: in vitro pilot study

BACKGROUND

Due to non-vascularized and aneural structure, articular cartilage has limited self-repairing capacity. The aim of this study was to investigate the revitalization of inflammatory injured articular cartilage matrices by human nasal chondrocytes (hNC).

MATERIALS AND METHODS

Cartilage matrix was prepared by devitalization of articular cartilage samples obtained intraoperatively from an adult patient undergoing knee joint replacement. hNC were obtained from native tissues by enzymatic digestion with further expansion over two passages. The obtained nasal chondrocytes were used to seed decellularized scaffolds, which were then cultured in vitro for 7, 14, or 21 days in chondrogenic medium. Migration was observed by histologic staining with fast green, safranin-O, and hematoxylin and scanning electron microscopy. Biochemical analysis was performed to determine the glycosaminoglycan (GAG) and DNA content of the cartilage using dimethylmethylene blue and CyQuant Cell Proliferation Assay Kit.

RESULTS

We seeded healthy and inflamed cartilage with nasal chondrocytes and found that the cells actively invade mainly pathologically altered cartilage. The results of biochemical quantitative analysis showed that the amount of DNA significantly increased by day 7 and decreased by day 14, while the quantitative values of GAGs had the opposite trend. Histological staining showed that cartilage formation occurred on day 7, intercellular spaces were filled with de novo synthesized cartilage matrix with significantly low GAG content on day 14, and newly formed GAG-rich cartilage was observed on day 21. The obtained data on cartilage regeneration were confirmed by scanning electron microscopy.

CONCLUSIONS

Our preliminary results showed that human nasal chondrocytes are capable of infiltrating the pathologically altered extracellular matrix of articular cartilage damaged by arthritis, thereby promoting its repair to a physiologically relevant state.

The Role of Mast Cells in the Remodeling Effects of Molecular Hydrogen on the Lung Local Tissue Microenvironment under Simulated Pulmonary Hypertension

Molecular hydrogen (H2) has antioxidant, anti-inflammatory, and anti-fibrotic effects. In a rat model simulating pulmonary fibrotic changes induced by monocrotaline-induced pulmonary hypertension (MPH), we had previously explored the impact of inhaled H2 on lung inflammation and blood pressure. In this study, we further focused the biological effects of H2 on mast cells (MCs) and the parameters of the fibrotic phenotype of the local tissue microenvironment. MPH resulted in a significantly increased number of MCs in both the pneumatic and respiratory parts of the lungs, an increased number of tryptase-positive MCs with increased expression of TGF-β, activated interaction with immunocompetent cells (macrophages and plasma cells) and fibroblasts, and increased MC colocalization with a fibrous component of the extracellular matrix of connective tissue. The alteration in the properties of the MC population occurred together with intensified collagen fibrillogenesis and an increase in the integral volume of collagen and elastic fibers of the extracellular matrix of the pulmonary connective tissue. The exposure of H2 together with monocrotaline (MCT), despite individual differences between animals, tended to decrease the intrapulmonary MC population and the severity of the fibrotic phenotype of the local tissue microenvironment compared to changes in animals exposed to the MCT effect alone. In addition, the activity of collagen fibrillogenesis associated with MCs and the expression of TGF-β and tryptase in MCs decreased, accompanied by a reduction in the absolute and relative content of reticular and elastic fibers in the lung stroma. Thus, with MCT exposure, inhaled H2 has antifibrotic effects involving MCs in the lungs of rats. This reveals the unknown development mechanisms of the biological effects of H2 on the remodeling features of the extracellular matrix under inflammatory background conditions of the tissue microenvironment.

Biological Efficacy of Ionizing Radiation Sources on 3D Organotypic Tissue Slices Assessed by Fluorescence Microscopy

OBJECTIVE

Traditional cell-based radiobiological methods are inadequate for assessing the toxicity of ionizing radiation exposure in relation to the microstructure of the extracellular matrix. Organotypic tissue slices preserve the spatial organization observed in vivo, making the tissue easily accessible for visualization and staining. This study aims to explore the use of fluorescence microscopy of physiologically relevant 3D tissue cultures to assess the effects of ionizing radiation.

METHODS

Organotypic tissue slices were obtained by vibratome, and their mechanical properties were studied. Slices were exposed by two ionizing radiation sources; electron beams (80 Gy and 4 Gy), and soft gamma irradiation (80 Gy and 4 Gy). Two tissue culture protocols were used: the standard (37°C), and hypothermic (30°C) conditions. A qualitative analysis of cell viability in organotypic tissue slices was performed using fluorescent dyes and standard laser confocal microscopy.

RESULTS

Biological dosimetry is represented by differentially stained 200-μm thick organotypic tissue sections related to living and dead cells and cell metabolic activity.

CONCLUSION

Our results underscore the ability of fluorescence laser scanning confocal microscopy to rapidly assess the radiobiological effects of ionizing radiation in vitro on 3D organotypic tissue slices.

ИСПОЛЬЗОВАНИЕ ИМПУЛЬСНОГО ЛАЗЕРНОГО ИК-ИЗЛУЧЕНИЯ С ДЛИНОЙ ВОЛНЫ 1,06 МКМ ДЛЯ ФОРМИРОВАНИЯ СПЕЦИАЛЬНОЙ МИКРОСТРУКТУРЫ В ХРЯЩЕВОЙ ТКАНИ

Использование лазерного излучения для диагностики и лечения находит широкое применение в реконструктивной хирургии. Однако в последние годы получила развитие новая область применения лазерного излучения - тканевая инженерия. В настоящей работе исследовалась возможность использования лазерного инфракрасного излучения длиной волны λ=1,06 мкм для создания матриксов для тканеинженерных конструкций. В работе показана возможность использования лазерного излучения с λ=1,06 мкм для создания имплантатов на основе хрящевой ткани ушной раковины кролика. Лазерная перфорация доказала свою эффективность для микроструктурной модификации поверхности ушного хряща кролика. Формирование микроструктуры, которую в последующем можно использовать в качестве тканеинженерной конструкции, происходит в результате индуцирования неоднородного температурного поля вследствие нерезонансных оптических потерь из-за рассеяния на компонентах биоткани с масштабом 1-5 мкм.

Advancing dermatology: artificial intelligence-based solutions to reducing the risk of misdiagnosis

Artificial intelligence has potential applications in dermatology in reducing rates of misdiagnosis. Despite evidence-based recommendations, misdiagnosis still occurs due to the complexity of the problem. Multispectral imaging, such as near- and far-infrared imaging, has the potential to aid in the identification of skin malignancies.

World's First Experience of the Low-Dose Radionuclide Inhalation Therapy in the Treatment of COVID-19-Associated Viral Pneumonia: Phase 1/2 Clinical Trial

OBJECTIVE

Previously, low-dose radiation therapy was used for pneumonia treatment. We aimed to investigate the safety and effectiveness of carbon nanoparticles labeled with Technetium isotope (99mTc) in a form of ultradispersed aerosol in combination with standard COVID-19 therapy. The study was a randomized phase 1 and phase 2 clinical trial of low-dose radionuclide inhalation therapy for patients with COVID-19 related pneumonia.

METHODS

We enrolled 47 patients with confirmed COVID-19 infection and early laboratory signs of cytokine storm and randomized them into the Treatment and Control groups. We analyzed blood parameters reflecting the COVID-19 severity and inflammatory response.

RESULTS

Low-dose 99mTc-labeled inhalation showed a minimal accumulation of radionuclide in lungs in healthy volunteers. We observed no significant differences between the groups before treatment in WBC-count, D-dimer, CRP, Ferritin or LDH levels. We found that Ferritin and LDH levels significantly raised after the 7th day follow-up only in the Control group (p < 0.0001 and p = 0.0005, respectively), while mean values of the same indicators did not change in patients in the Treatment group after the radionuclide treatment. D-dimer values also lowered in the radionuclide treated group, however, this effect was not statistically significant. Furthermore, we observed a significant decrease in CD19+ cell counts in patients of the radionuclide-treated group.

CONCLUSION

Inhalation low-dose radionuclide therapy of 99mTc aerosol affects the major prognostic indicators of COVID-19- related pneumonia restraining inflammatory response. Overall, we identified no evidence of major adverse events in the group receiving radionuclide.

Tumor-Associated Extracellular Matrix Obstacles for CAR-T Cell Therapy: Approaches to Overcoming

Chimeric antigen receptor (CAR)-T cell therapy yields good results in the treatment of various hematologic malignancies. However, the efficacy of CAR-T cell therapy against solid tumors has proven to be limited, primarily because the tumor-associated extracellular matrix (ECM) creates an intractable barrier for the cytotoxic CAR-T cells that are supposed to kill cancer cells. This review unravels the multifaceted role of the tumor-associated ECM in impeding CAR-T cell infiltration, survival, and functions within solid tumors. We analyze the situations when intratumoral ECM limits the efficacy of CAR-T cell therapy by being a purely physical barrier that complicates lymphocyte penetration/migration and also acts as an immunosuppressive factor that impairs the antitumor activities of CAR-T cells. In addition, we highlight promising approaches such as engineering CAR-T cells with improved capabilities to penetrate and migrate into/through the intratumoral ECM, combination therapies aimed at attenuating the high density and immunosuppressive potential of the intratumoral ECM, and others that enable overcoming ECM-related obstacles. A detailed overview of the data of relevant studies not only helps to better understand the interactions between CAR-T cells and the intratumoral ECM but also outlines potential ways to more effectively use CAR-T cell therapy against solid tumors.

Foreshadowing the Future of Genetic Engineering and Radiobiology: 100 Years From the Beginning of N.V. Timofeeff-Ressovsky’s Scientific Work

The year 2021 was marked with a significant date – 100 years ago, brilliant radiobiologist and geneticist N.V. Timofeeff-Ressovsky started his scientific work. Among the new directions developed by him from 1921 to 1981 were physical biology, basic principles of genetic engineering, amplifier principle, and population radiobiology. It is noteworthy that many of his ideas were developed in the former Department of Radiation Genetics and General Radiobiology of the Institute of Medical Radiology in Obninsk, which is now called the Experimental Sector of the A. Tsyb Medical Radiological Research Centrе. Our work reveals the interconnections of Timofeeff-Ressovsky’s works with the activities of his contemporaries and productive ideas of today.

Refinement of Animal Experiments: Replacing Traumatic Methods of Laboratory Animal Marking with Non-Invasive Alternatives

Reliable methods for identifying rodents play an important role in ensuring the success of preclinical studies. However, animal identification remains a trivial laboratory routine that is not often discussed, despite the fact that more than 6 million rodents are used in animal studies each year. Currently, there are extensive regulations in place to ensure adequate anesthesia and to reduce animal suffering during experiments. At the same time, not enough attention is paid to the comfort of rodents during routine identification procedures, which can be painful and cause some complications. In order to achieve the highest ethical standards in laboratory research, we must minimize animal discomfort during the identification phase. In this article, we discuss traumatic methods of identification and describe several painless methods for marking in long-term experimental studies. The use of non-traumatic and non-invasive methods requires the renewal of marks as they fade and additional handling of the rodents. Laboratory personnel must be trained in stress-minimizing handling techniques to make mark renewal less stressful.

The World's First Implantation of a Personalized Microporous Titanium Sternum with Motile Costal Clip Connections: A Case Report

Extensive chest wall defects occur in 28% of all sternal resection cases and are a major challenge in thoracic surgery. These cases are generally considered "critical defects" requiring primary or secondary reconstruction using various types of flaps, mesh repairs, bone autografts, or endoprosthesis. The past decade witnessed rapid advances in the application of personalized endoprostheses in thoracic surgery. Surgeons began to use carbon or titanium grafts for personalized sternum replacement. The main advantages of these implants are superior cosmetic effect, biocompatibility, and low risk of infection. Herein, we present a case of a 55-year-old patient with an indication for extended sternum resection due to metastatic thyroid cancer. The patient underwent extended sternum resection, followed by the implantation of a personalized microporous titanium sternum equipped with graspers for atraumatic rib fixation.

[Possible use of the growing liver biological set for hepatic recovery after toxic damage (an experimental study)]

The lack of acceptable pharmacological approaches for restoration of the injured liver is associated with complex of mechanisms involved in hepatic regeneration and with difficulty of the target selection. The aim of this research was to study the hepatoprotective function of the extract from both the growing and regenerating liver containing a natural set of factors crucial for the hepatic restoration. Extracts from both regenerating liver of rats after 70% hepatic resection and the growing liver of neonatal pigs were obtained using own original technique. The set of resultant extracts was named as the hepatic regeneration set (HRS). HRS fractionation was carried out using the Toyopearl HW-50S sorbent. The efficiency of HRS and its fractions was estimated using a model of the mouse liver thioacetamide injury and monitoring hepatic enzyme activity in blood serum. The activities of AST and ALT in intact animals were 50 U/l and 80 U/l, respectively; after thioacetamide administration they increased to 2059±212 U/l and 4280±440 E/l, respectively (p<0.05). Treatment of injured animals with HRS from the rat regenerating liver resulted in a significant decrease of transaminase activities to 924±148 U/l (AST; p<0.05) and 1633±308 U/l (ALT; p<0.05). A similar effect was observed after treatment with HRS from the neonatal pig liver: the AST decreased to 937±138 U/l (p<0.05), while ALT activity decreased to 1710±237 U/l (p<0.05). HRs fractionation resulted in identification two active fractions characterized by much higher (8-29) hepatotropic effect that that of the whole extract. These fractions contained peptide/protein components with the range of molecular mass of 3-60 kDa (fraction 1) and 3-25 kDa (fraction 2a). Fraction 1 also contained some polynucleotides in fraction 1. Subsequent studies of these fractions exceeding the hepatotropic effect of original HRS is clearly needed to identify their individual components by immunochromatography methods, ELISA, MRM mass spectrometry and quantitative PCR.

Angiogenic vitalization of biocompatible and biodegradable scaffold ( experimental study)

Цель исследования - оценка влияния на ангиогенез конструкций из волокнистого поликапролактона, модифицированного плазмидой с геном сосудистого фактора роста, при имплантации крысам. Методика. Эксперименты выполнены на 24 крысах-самках Вистар в возрасте 2 мес, массой 180-200 г. В работе исследовали плоские каркасы размером 1 см х 1 см, полученные методом эмульсионного электроспиннинга из раствора поликапролактона. Материал каркасов витализировали плазмидой VEGF-165 (геннотерапевтический препарат Неоваскулген), введенной внутрь двух типов волокнистых материалов в разных концентрациях: низкой - 0,005 мг/мл, и высокой - 0,05 мг/мл. Образец и контроль (материал без витализации) одномоментно имплантировали подкожно в два сформированных симметричных кармана в межлопаточной зоне. Окружающие каркас ткани на 7-е, 16-е, 33-и, 46-е и 64-е сутки извлекали, проводили гистологическое исследование: изучали тканевую реакцию с морфометрической оценкой плотности распределения и диаметра сосудов в области имплантации, а также оценивали степень биодеградации волокнистого материала. Результаты. Признаков тканевой реакции отторжения при имплантации как контрольного, так и модифицированного материала не выявлено. Показано, что при экспозиции материала in vivo наряду с резорбцией материала происходят изменения количества и диаметра сосудов. Выявлен дозозависимый эффект стимуляции ангиогенеза при увеличении концентрации Неоваскулгена в образцах. Для витализированных материалов отмечено увеличение плотности распределения сосудов на 46% (высокая концентрация, 33-и сут) по сравнению с контролем. После прекращения воздействия препарата, плотность распределения сосудов приближалась к значениям в контроле. Заключение. Разработанная методика витализации полимерных каркасов с внесением раствора геннотерапевтического препарата Неоваскулген внутрь микроволокон обеспечивает пролонгированный и дозозависимый эффект на рост сосудов в зоне имплантации.

The aim of the study was to evaluate the effect on angiogenesis of a biocompatible, biodegradable material-derived scaffold implanted into rats and functionalized using a plasmid with a vascular growth factor gene. Methods. Experiments were performed on 24 female Wistar rats aged 2 months weighing 180-200 g. We investigated 1 cm x 1 cm flat scaffolds obtained by electrospinning from polycaprolactone functionalized scaffolds with a VEGF-165 plasmid (gene therapy drug, Neovasculgen) incorporated inside the fibers at two concentrations, low (0.005 mg/ml) and high (0.05 mg/ml). The sample and control were simultaneously implanted subcutaneously into two formed symmetrical pockets in the interblade zone. At 7, 16, 33, 46, and 64 days, the scaffolds were removed, and histological examination was performed; the tissue reaction was studied including morphometric evaluation of density and diameter of blood vessels in the implantation area, and the area of the image occupied by the material was measured. Results. Tissue rejection was absent after implantation of either control or modified material. When the material was exposed in vivo , besides resorption of the material, blood vessel number and diameter changed. As the Neovasculgen concentration in samples increased, a dose-dependent effect of angiogenesis stimulation became evident. Vascular density was increased by 46% (high concentration, 33 days) in functionalized matrices compared to the control. After cessation of the drug treatment, the vascular density approached the control values. Conclusion. The developed technique for functionalizing polymeric scaffolds by administration of a solution of the gene therapy drug, Neovasculgen, into microfibers provides a prolonged and dose-dependent effect on growth of blood vessels in the implantation zone.

Population Studies and Molecular Mechanisms of Human Radioadaptive Capabilities: Is It Time to Rethink Radiation Safety Standards?

The evolution of man on Earth took place under conditions of constant exposure to background ionizing radiation (IR). From this point of view, it would be reasonable to hypothesize the existence of adaptive mechanisms that enable the human organism to safely interact with IR at levels approximating long-term natural background levels. In some situations, the successful operation of molecular mechanisms of protection against IR is observed at values significantly exceeding the natural background level, for example, in cancer cells. In 15-25% of cancer patients, cancer cells develop a phenotype that is resistant to high doses of IR. While further investigations are warranted, the current evidence suggests a strong probability of observing positive health effects, including an increased lifespan, a reduced cancer risk, and a decreased incidence of congenital pathologies, precisely at low doses of ionizing radiation. This review offers arguments primarily based on a phenomenological approach and critically reconsidering existing methodologies for assessing the biological risks of IR to human health. Currently, in the most economically developed countries, there are radiation safety rules that interpret low-dose radiation as a clearly negative environmental factor. Nowadays, this approach may pose significant challenges to the advancement of radiomedicine and introduce complexities in the regulation of IR sources. The review also examines molecular mechanisms that may play a key role in the formation of the positive effects of low-dose IR on human radioadaptive capabilities.

Local Application of Minimally Manipulated Autologous Stromal Vascular Fraction (SVF) Reduces Inflammation and Improves Bilio-Biliary Anastomosis Integrity

Bilio-biliary anastomosis (BBA) is a critical surgical procedure that is performed with the objective of restoring bile duct continuity. This procedure is often required in cases where there has been an injury to the extrahepatic bile ducts or during liver transplantation. Despite advances in surgical techniques, the healing of BBA remains a significant challenge, with complications such as stricture formation and leakage affecting patient outcomes. The stromal vascular fraction (SVF), a heterogeneous cell population derived from adipose tissue, has demonstrated promise in regenerative medicine due to its rich content of stem cells, endothelial progenitor cells, and growth factors. The objective of this study was to evaluate the potential of locally administered autologous SVF to enhance the healing of BBAs. Bilio-biliary anastomosis was performed on a swine model (female Landrace pigs). Six swine were divided into two groups: the treatment group (n = 3) received a local application of autologous SVF around the anastomosis site immediately following BBA formation, while the control group (n = 3) received saline. The primary outcomes were assessed over an eight-week period post-surgery, and included anastomosis healing, stricture formation, and bile leakage. Histological analysis was performed to evaluate fibrosis, angiogenesis, and inflammation. Immunohistochemistry was conducted to assess healing-related markers (CD34, α-SMA) and the immunological microenvironment (CD3, CD10, tryptase). The SVF-treated group exhibited significantly enhanced healing of the BBA. Histological examination revealed increased angiogenesis and reduced fibrosis in the SVF group. Immunohistochemical staining demonstrated higher vascular density in the anastomosed area of the SVF-treated group (390 vs. 210 vessels per 1 mm2, p = 0.0027), as well as a decrease in wall thickness (1.9 vs. 1.0 mm, p = 0.0014). There were no statistically significant differences in mast cell presence (p = 0.40). Immunohistochemical staining confirmed the overexpression of markers associated with tissue repair. Local injections of autologous SVF at the site of BBA have been demonstrated to significantly enhance healing and promote tissue regeneration. These findings suggest that SVF could be a valuable adjunctive therapy in BBA surgery, potentially improving surgical outcomes. However, further investigation is needed to explore the clinical applicability and long-term benefits of this novel approach in clinical practice as a minimally manipulated cell application.

Cyto- and Histopographic Assessment of CPA3-Positive Testicular Mast Cells in Obstructive and Non-Obstructive Azoospermia

Infertility is an important personal and society disease, of which the male factor represents half of all causes. One of the aspects less studied in male infertility is the immunological testicular microenvironment. Mast cells (MCs), having high potential for regulating spermatogenesis due to fine-tuning the state of the integrative buffer metabolic environment, are one of the most crucial cellular subpopulations of the testicular interstitium. One important component of the MC secretome is proteases that can act as proinflammatory agents and in extracellular matrix (ECM) remodeling. In the testis, MCs are an important cell component of the testicular interstitial tissue (TIT). However, there are still no studies addressing the analysis of a specific MC protease-carboxypeptidase A3 (CPA3)-in cases with altered spermatogenesis. The cytological and histotopographic features of testicular CPA3+ MCs were examined in a study involving 34 men with azoospermia. As revealed, in cases with non-obstructive azoospermia, a higher content of CPA3+ MCs in the TIT and migration to the microvasculature and peritubular tissue of seminiferous tubules were observed when compared with cases with obstructive azoospermia. Additionally, a high frequency of CPA3+ MCs colocalization with fibroblasts, Leydig cells, and elastic fibers was detected in cases with NOA. Thus, CPA3 seems to be of crucial pathogenetic significance in the formation of a profibrogenic background of the tissue microenvironment, which may have direct and indirect effects on spermatogenesis.

The effects of mesenchymal stromal cells and platelet-rich plasma treatments on cutaneous wound healing: ignoring the possibility of adverse events and side effects could compromise study results

Common medical events may be associated with decreased immunologic activity and dysregulation of functional epithelial and neuronal tissues caused by growth factors and vesicle secretion by stem and somatic cells. Systemic injection of MSCs has been shown to reduce the immune response mainly through paracrine mechanisms, but some points related to the possibility of adverse events and side effects should be clarified. Flow cytometry for at least 20 cell markers is crucial to assess cell senescence and overall cell viability. Thus, adverse events and unreasonable expectations from cell therapy can be prevented. We believe that by using the precision cell phenotyping kits in clinical trials, many undesirable side effects related to misconceptions about the origin of the cells can be avoided.