Adverse events, side effects and complications in mesenchymal stromal cell-based therapies

Numerous clinical studies have shown a wide clinical potential of mesenchymal stromal cells (MSCs) application. However, recent experience has accumulated numerous reports of adverse events and side effects associated with MSCs therapy. Furthermore, the strategies and methods of MSCs therapy did not change significantly in recent decades despite the clinical impact and awareness of potential complications. An extended understanding of limitations could lead to a wider clinical implementation of safe cell therapies and avoid harmful approaches. Therefore, our objective was to summarize the possible negative effects observed during MSCs-based therapies. We were also aimed to discuss the risks caused by weaknesses in cell processing, including isolation, culturing, and storage. Cell processing and cell culture could dramatically influence cell population profile, change protein expression and cell differentiation paving the way for future negative effects. Long-term cell culture led to accumulation of chromosomal abnormalities. Overdosed antibiotics in culture media enhanced the risk of mycoplasma contamination. Clinical trials reported thromboembolism and fibrosis as the most common adverse events of MSCs therapy. Their delayed manifestation generally depends on the patient's individual phenotype and requires specific awareness during the clinical trials with obligatory inclusion in the patient' informed consents. Finally we prepared the safety checklist, recommended for clinical specialists before administration or planning of MSCs therapy.

212Pb: Production Approaches and Targeted Therapy Applications

Over the last decade, targeted alpha therapy has demonstrated its high effectiveness in treating various oncological diseases. Lead-212, with a convenient half-life of 10.64 h, and daughter alpha-emitter short-lived 212Bi (T1/2 = 1 h), provides the possibility for the synthesis and purification of complex radiopharmaceuticals with minimum loss of radioactivity during preparation. As a benefit for clinical implementation, it can be milked from a radionuclide generator in different ways. The main approaches applied for these purposes are considered and described in this review, including chromatographic, solution, and other techniques to isolate 212Pb from its parent radionuclide. Furthermore, molecules used for lead's binding and radiochemical features of preparation and stability of compounds labeled with 212Pb are discussed. The results of preclinical studies with an estimation of therapeutic and tolerant doses as well as recently initiated clinical trials of targeted radiopharmaceuticals are presented.

Stem and Somatic Cell Monotherapy for the Treatment of Diabetic Foot Ulcers: Review of Clinical Studies and Mechanisms of Action

Diabetic foot ulcer (DFU) is one of the most severe complications of diabetes mellitus, often resulting in a limb amputation. A cell-based therapy is a highly promising approach for an effective DFU treatment. However, there is no consensus regarding the most effective cell type for DFU treatment. Various cell types contribute to chronic wound healing via different mechanisms. For example, application of keratinocytes can stimulate migration of native keratinocytes from the wound edge, while mesenchymal stem cells can correct limb ischemia. To assess the effectiveness of a certain cell type, it should be administered as a monotherapy without other substances and procedures that have additional therapeutic effects. In the present review, we described therapeutic effects of various cells and provided an overview of clinical studies in which stem and somatic cell-based therapy was administered as a monotherapy. Topical application of somatic cells contributes to DFU healing only, while injection of mesenchymal stem cells and mononuclear cells can break a pathophysiological chain leading from insufficient blood supply to DFU development. At the same time, the systemic use of mesenchymal stem cells carries greater risks. Undoubtedly, cell therapy is a potent tool for the treatment of DFU. However, it is vital to conduct further high-quality clinical research to determine the most effective cell type, dosage and way of administration for DFU treatment. Ischemia, neuropathy and neuro-ischemia are underlying factors of diabetic foot ulcer. Stem and somatic cells monotherapy can improve chronic wound healing via different mechanisms.

Mesenchymal Stromal Cells as a Driver of Inflammaging

Life expectancy and age-related diseases burden increased significantly over the past few decades. Age-related conditions are commonly discussed in a very limited paradigm of depleted cellular proliferation and maturation with exponential accumulation of senescent cells. However, most recent evidence showed that the majority of age-associated ailments, i.e., diabetes mellitus, cardiovascular diseases and neurodegeneration. These diseases are closely associated with tissue nonspecific inflammation triggered and controlled by mesenchymal stromal cell secretion. Mesenchymal stromal cells (MSCs) are known as the most common type of cells for therapeutic approaches in clinical practice. Side effects and complications of MSC-based treatments increased interest in the MSCs secretome as an alternative concept for validation tests in regenerative medicine. The most recent data also proposed it as an ideal tool for cell-free regenerative therapy and tissue engineering. However, senescent MSCs secretome was shown to hold the role of 'key-driver' in inflammaging. We aimed to review the immunomodulatory effects of the MSCs-secretome during cell senescence and provide eventual insight into the interpretation of its beneficial biological actions in inflammaging-associated diseases.

Prolonged prothrombin time as an early prognostic indicator of severe acute respiratory distress syndrome in patients with COVID-19 related pneumonia

BACKGROUND

Clinical observations demonstrated that COVID-19 related pneumonia is often accompanied by hematological and coagulation abnormalities including lymphopenia, thrombocytopenia, and prolonged prothrombin time. The evaluation of laboratory findings including coagulation and inflammation parameters may represent a promising approach for early determination of COVID-19 severity.

METHODS AND MATERIALS

In the present study, we aimed to identify laboratory parameters present upon admission in patients with COVID-19 related viral pneumonia and associated with an early in-hospital development of refractory respiratory failure or severe acute respiratory distress syndrome requiring treatment in an intensive care unit. We investigated differences in the C-reactive protein (CRP) and fibrinogen levels, prothrombin time (PT) and international normalized ratio (INR) between COVID-19 patients who had been transferred to an ICU within two weeks after admission (n = 82) and COVID-19 patients with stable course of the disease (n = 74).

RESULTS

Multiple comparisons showed statistically significantly prolonged PT on admission in ICU-transferred COVID-19 patients (14.15 sec, median, CI 95% 13.4 ÷ 14.9) compared to the stable COVID-19 patients (13.25 sec, median, CI 95% 12.9 ÷ 13.6) (p-value = .0005). CRP levels upon admission were statistically significantly higher in ICU-transferred COVID-19 patients (132 mg/L, median, CI95% 113 ÷ 159) compared to the stable COVID-19 patients (51 mg/L, median, CI95% 33 ÷ 72) (p-value < .0001). On-admission fibrinogen and INR levels did not statistically significantly differ between ICU-transferred COVID-19 patients and stable COVID-19 patients.

CONCLUSION

We suggest that CRP and PT levels present on admission in COVID-19 patients may be used as early prognostic markers of severe pneumonia requiring transfer to ICU.

Mesenchymal Stromal Cells Enhance Vascularization and Epithelialization within 7 Days after Gingival Augmentation with Collagen Matrices in Rabbits

Soft gingival tissue deficiency remains a severe problem leading to postoperative recession, peri-implantitis, and bone resorption. The use of collagen matrices does not always lead to complete rebuilding of the gingiva volume. The application of mesenchymal stromal cells (MSCs) simultaneously with collagen materials represents a promising approach for the restoration of soft gingival tissues. However, short-term effects of MSCs-enriched collagen grafts after gingival augmentation have not yet been studied properly. Mucograft and Mucoderm matrices were implanted in rabbits (n = 12) simultaneously with the intraoperative injection of rabbit bone marrow-derived mesenchymal stromal cells (BM-MSCs) or without cells. Collagen matrices were implanted under the flap or by the surface technique without intentional primary closure. The samples were harvested seven days after implantation, histological staining with hematoxylin and eosin, and immunohistochemical staining for VEGF, IGF1, and TGF were performed. The use of Mucoderm led to better augmentation outcomes on day 7 compared with Mucograft (p < 0.0001). Gingival augmentation in combination with the local administration of BM-MSCs led to better regeneration of the soft gingival tissues independently of the type of implanted collagen matrices (p < 0.0001). Furthermore, injection of BM-MSCs significantly enhanced gingival vascularization and epithelization with a clear positive correlation between vascular growth and epithelial response. Administration of BM-MSCs in combination with various collagen materials may potentially improve gingiva regeneration.

Biomechanical Behaviors and Degradation Properties of Multilayered Polymer Scaffolds: The Phase Space Method for Bile Duct Design and Bioengineering

This article reports the electrospinning technique for the manufacturing of multilayered scaffolds for bile duct tissue engineering based on an inner layer of polycaprolactone (PCL) and an outer layer either of a copolymer of D,L-lactide and glycolide (PLGA) or a copolymer of L-lactide and ε-caprolactone (PLCL). A study of the degradation properties of separate polymers showed that flat PCL samples exhibited the highest resistance to hydrolysis in comparison with PLGA and PLCL. Irrespective of the liquid-phase nature, no significant mass loss of PCL samples was found in 140 days of incubation. The PLCL- and PLGA-based flat samples were more prone to hydrolysis within the same period of time, which was confirmed by the increased loss of mass and a significant reduction of weight-average molecular mass. The study of the mechanical properties of developed multi-layered tubular scaffolds revealed that their strength in the longitudinal and transverse directions was comparable with the values measured for a decellularized bile duct. The strength of three-layered scaffolds declined significantly because of the active degradation of the outer layer made of PLGA. The strength of scaffolds with the PLCL outer layer deteriorated much less with time, both in the axial (p-value = 0.0016) and radial (p-value = 0.0022) directions. A novel method for assessment of the physiological relevance of synthetic scaffolds was developed and named the phase space approach for assessment of physiological relevance. Two-dimensional phase space (elongation modulus and tensile strength) was used for the assessment and visualization of the physiological relevance of scaffolds for bile duct bioengineering. In conclusion, the design of scaffolds for the creation of physiologically relevant tissue-engineered bile ducts should be based not only on biodegradation properties but also on the biomechanical time-related behavior of various compositions of polymers and copolymers.

Misdiagnosis of diabetic foot ulcer in patients with undiagnosed skin malignancies

A growing number of studies report dermal malignancies mimicking diabetic foot ulcers (DFUs). We reviewed clinical cases reporting malignant tumours misdiagnosed to be DFU aiming to identify factors contributing to misdiagnosis. We systematically searched in PubMed for clinical cases reporting on misdiagnosis of DFU in patients with cancer. A chi-square analysis was conducted to show the link between the incidence of initial DFU misdiagnosis and patient age, gender and wound duration. Lesions misdiagnosed to be DFU were subsequently diagnosed as melanoma (68% of the cases), Kaposi's sarcoma (14%), squamous cell carcinoma (11%), mantle cell lymphoma, and diffuse B-cell lymphoma (both by 4%). Older age (≥65 years) was associated with a significantly increased risk of malignancy masked as DFU (OR: 2.452; 95% CI: 1.132 to 5.312; P value = .019). The risk of such suspicion in older patients (age ≥ 65 years) was 145% higher than in younger patients (age < 65 years). Clinicians should maintain a high level of awareness towards potentially malignant foot lesions in elderly patients with diabetes (age ≥ 65).

Angiogenic Modification of Microfibrous Polycaprolactone by pCMV-VEGF165 Plasmid Promotes Local Vascular Growth after Implantation in Rats

Insufficient vascular growth in the area of artificial-material implantation contributes to ischemia, fibrosis, the development of bacterial infections, and tissue necrosis around the graft. The purpose of this study was to evaluate angiogenesis after implantation of polycaprolactone microfiber scaffolds modified by a pCMV-VEGF165-plasmid in rats. Influence of vascularization on scaffold degradation was also examined. We investigated flat microfibrous scaffolds obtained by electrospinning polycaprolactone with incorporation of the pCMV-VEGF-165 plasmid into the microfibers at concentrations of 0.005 ng of plasmid per 1 mg of polycaprolactone (0.005 ng/mg) (LCGroup) and 0.05 ng/mg (HCGroup). The samples were subcutaneously implanted in the interscapular area of rats. On days 7, 16, 33, 46, and 64, the scaffolds were removed, and a histological study with a morphometric evaluation of the density and diameter of the vessels and microfiber diameter was performed. The number of vessels was increased in all groups, as well as the resorption of the scaffold. On day 33, the vascular density in the HCGroup was 42% higher compared to the control group (p = 0.0344). The dose-dependent effect of the pCMV-VEGF165-plasmid was confirmed by enhanced angiogenesis in the HCGroup compared to the LCGroup on day 33 (p-value = 0.0259). We did not find a statistically significant correlation between scaffold degradation rate and vessel growth (the Pearson correlation coefficient was ρ = 0.20, p-value = 0.6134). Functionalization of polycaprolactone by incorporation of the pCMV-VEGF165 plasmid provided improved vascularization within 33 days after implantation, however, vessel growth did not seem to correlate with scaffold degradation rate.

Post-Implantation Inflammatory Responses to Xenogeneic Tissue-Engineered Cartilage Implanted in Rabbit Trachea: The Role of Cultured Chondrocytes in the Modification of Inflammation

Immune responses to tissue-engineered grafts made of xenogeneic materials remain poorly studied. The scope of current investigations is limited by the lack of information on orthotopically implanted grafts. A deeper understanding of these processes is of great importance since innovative surgical approaches include the implantation of xenogeneic decellularized scaffolds seeded by cells. The purpose of our work is to study the immunological features of tracheal repair during the implantation of tissue-engineered constructs based on human xenogeneic scaffolds modified via laser radiation in rabbits. The samples were stained with hematoxylin and Safranin O, and they were immunostained with antibodies against tryptase, collagen II, vimentin, and CD34. Immunological and inflammatory responses were studied by counting immune cells and evaluating blood vessels and collagen. Leukocyte-based inflammation prevailed during the implantation of decellularized unseeded scaffolds; meanwhile, plasma cells were significantly more abundant in tissue-engineered constructs. Mast cells were insignificantly more abundant in tissue-engineered construct samples. Conclusions: The seeding of decellularized xenogeneic cartilage with chondrocytes resulted in a change in immunological reactions upon implantation, and it was associated with plasma cell infiltration. Tissue-engineered grafts widely differed in design, including the type of used cells. The question of immunological response depending on the tissue-engineered graft composition requires further investigation.

Engineering of Tracheal Grafts Based on Recellularization of Laser-Engraved Human Airway Cartilage Substrates

OBJECTIVE

Implantation of tissue-engineered tracheal grafts represents a visionary strategy for the reconstruction of tracheal wall defects after resections and may develop into a last chance for a number of patients with severe cicatricial stenosis. The use of a decellularized tracheal substrate would offer an ideally stiff graft, but the matrix density would challenge efficient remodeling into a living cartilage. In this study, we hypothesized that the pores of decellularized laser-perforated tracheal cartilage (LPTC) tissues can be colonized by adult nasal chondrocytes (NCs) to produce new cartilage tissue suitable for the repair of tracheal defects.

DESIGN

Human, native tracheal specimens, isolated from cadaveric donors, were exposed to decellularized and laser engraving-controlled superficial perforation (300 μm depth). Human or rabbit NCs were cultured on the LPTCs for 1 week. The resulting revitalized tissues were implanted ectopically in nude mice or orthotopically in tracheal wall defects in rabbits. Tissues were assayed histologically and by microtomography analyses before and after implantation.

RESULTS

NCs were able to efficiently colonize the pores of the LPTCs. The extent of colonization (i.e., percentage of viable cells spanning >300 μm of tissue depth), cell morphology, and cartilage matrix deposition improved once the revitalized constructs were implanted ectopically in nude mice. LPTCs could be successfully grafted onto the tracheal wall of rabbits without any evidence of dislocation or tracheal stenosis, 8 weeks after implantation. Rabbit NCs, within the LPTCs, actively produced new cartilage matrix.

CONCLUSION

Implantation of NC-revitalized LPTCs represents a feasible strategy for the repair of tracheal wall defects.

Mesenchymal stromal cell therapy alone does not lead to complete restoration of skin parameters in diabetic foot patients within a 3-year follow-up period

Introduction: Mesenchymal stromal cells (MSCs) administration is an effective option for the treatment of diabetic foot ulcers (DFUs). However, to date, studies assessing long-term outcomes and evaluating skin parameters after cell-based therapy are lacking. We presented the clinical outcomes of 3 patients, treated for DFUs with the bone marrow MSCs 3 years earlier. Methods: Ultrasound examination was used to compare collagen density and epidermal thickness in areas of healed ulcers in comparison with non-affected skin used as a control. Ultrasound and dermatoscopy were used to exclude neoplasm formation, to assess scar contracture and wound recurrence. Results: In all patients, no ulcer recurrence was detected, which was lower than the expected 60% rate of re-ulceration in diabetic patients in a 3-year period (OD [odds ratio] = 0.095, P = 0.12). No neoplasm formation, no contracture of hypertrophic scar, and adjacent tissue were registered. Collagen ultrasound density was decreased by 57% (P = 0.053) and epidermal thickness was increased by 72% (P = 0.01) in the area of healed ulcers in all patients. Conclusion: MSCs therapy alone did not result in the complete restoration of the skin parameters within a 3-year period. MSCs may represent important adjuvant to the therapy, however, other novel approaches are required to achieve better results.

A Role of Variance in Interferon Genes to Disease Severity in COVID-19 Patients

The rapid rise and global consequences of the novel coronavirus disease 19 (COVID-19) have again brought the focus of the scientific community on the possible host factors involved in patient response and outcome to exposure to the virus. The disease severity remains highly unpredictable, and individuals with none of the aforementioned risk factors may still develop severe COVID-19. It was shown that genotype-related factors like an ABO Blood Group affect COVID-19 severity, and the risk of infection with SARS-CoV-2 was higher for patients with blood type A and lower for patients with blood type O. Currently it is not clear which specific genes are associated with COVID-19 severity. The comparative analysis of COVID-19 and other viral infections allows us to predict that the variants within the interferon pathway genes may serve as markers of the magnitude of immune response to specific pathogens. In particular, various members of Class III interferons (lambda) are reviewed in detail.

Minimally Manipulated Bone Marrow-Derived Cells Can Be Used for Tissue Engineering In Situ and Simultaneous Formation of Personalized Tissue Models

Red bone marrow and autologous bone tissue (bone fragments and bone chips) of the donor were harvested intraoperatively during autoplasty of talus bone defect. Titanium chips were obtained by grinding a fragment of a microporous titanium-coated hip arthroplasty (Zimmer). Bone marrow mononuclear cells were isolated in the operating room, and bone and titanium fragments were incubated with a suspension of mononuclear cells. The quality of revitalization was assessed by fluorescence microscopy and histological examination after culturing of adherent cells on the bone and titanium fragments. During culturing on bone chips, bone marrow mononuclear fraction cells demonstrated significantly higher metabolic activity than bone marrow cells (p=0.04). Mononuclear fraction cells were also capable of stable colonization of titanium fragments with the formation of composite tissue model.

Intraoperative Creation of Tissue-Engineered Grafts with Minimally Manipulated Cells: New Concept of Bone Tissue Engineering In Situ

Transfer of regenerative approaches into clinical practice is limited by strict legal regulation of in vitro expanded cells and risks associated with substantial manipulations. Isolation of cells for the enrichment of bone grafts directly in the Operating Room appears to be a promising solution for the translation of biomedical technologies into clinical practice. These intraoperative approaches could be generally characterized as a joint concept of tissue engineering in situ. Our review covers techniques of intraoperative cell isolation and seeding for the creation of tissue-engineered grafts in situ, that is, directly in the Operating Room. Up-to-date, the clinical use of tissue-engineered grafts created in vitro remains a highly inaccessible option. Fortunately, intraoperative tissue engineering in situ is already available for patients who need advanced treatment modalities.

Human endometrial stem cells: High-yield isolation and characterization

BACKGROUND

Menstrual blood is only recently and still poorly studied, but it is an abundant and noninvasive source of highly proliferative mesenchymal stromal cells (MSCs). However, no appropriate isolation method has been reported due to its high viscosity and high content of clots and desquamated epithelium.

METHODS

We studied three different isolation approaches and their combinations: ammonium-containing lysing buffer, distilled water and gradient-density centrifugation. We tested the proliferative capacity, morphology, surface markers and pluripotency of the resulting cells.

RESULTS

Our isolation method yields up to four million nucleated cells per milliliter of initial blood, of which about 0.2-0.3% are colony-forming cells expressing standard mesenchymal markers CD90, CD105 and CD73, but not expressing CD45, CD34, CD117, CD133 or HLA-G. The cells have high proliferative potential (doubling in 26 h) and the ability to differentiate into adipocytes and osteocytes. Early endometrial MSCs (eMSCs) express epithelial marker cytokeratin 7 (CK7). CK7 is easily induced in later passages in a prohepatic environment. We show for the first time that a satisfactory and stable yield of eMSCs is observed throughout the whole menstrual period (5 consecutive days) of a healthy woman.

DISCUSSION

The new cost/yield adequate method allows isolation from menstrual blood a relatively homogenous pool of highly proliferative MSCs, which seem to be the best candidates for internal organ therapy due to their proepithelial background (early expression of CK7 and its easy induction in later passages) and for mass cryobanking due to their high yield and availability.

Prognostic Value of Serum Transferrin Analysis in Patients with Ovarian Cancer and Cancer-Related Functional Iron Deficiency: A Retrospective Case-Control Study

(1) Background: There are no reliable and widely available markers of functional iron deficiency (FID) in cancer. The aim of the study was to evaluate the role of transferrin (Tf) as a marker of cancer of the ovary (CrO) and related FID. (2) Methods: The study groups consisted of 118 patients with CrO and 69 control females. Blood serum iron status was determined on a Beckman Coulter AU (USA) analyzer. Tf quantification was performed by immunoturbidimetry. The relative contents of apo- and holo-Tf (iron-free and iron-saturated Tf, respectively) were determined in eight patients and a control female by immunochromatographic analysis based on the use of monoclonal single-domain antibodies (nanobodies). (3) Results: Four groups of patients with different iron statuses were selected according to ferritin and transferrin saturation values: absolute iron deficiency (AID) (n = 42), FID (n = 70), iron overload (n = 4), normal iron status (n = 2). The groups differed significantly in Tf values (p < 0.0001). Lower values of Tf were associated with FID. Furthermore, FID is already found in the initial stages of CrO (26%). Immunosorbents based on nanobodies revealed the accumulation of apo-Tf and the decrease in holo-Tf in patients with CrO. (4) Conclusions: Tf may be a promising tool for diagnosing both CrO and associated FID.

Modification of biodegradable fibrous scaffolds with Epidermal Growth Factor by emulsion electrospinning for promotion of epithelial cells proliferation

Supporting of a physiologically relevant cellular micro-environment is currently a grand challenge in the design of tissue-engineering grafts based on biocompatible and biodegradable polymeric materials. The aim of this research was to develop a new technique of a fibrous polycaprolactone-based scaffold modification with epidermal growth factor (EGF) and assessment of its effect on scaffold properties and proliferative activity of epithelial cells in vitro. Fibrous scaffolds from EGF-functionalized polycaprolactone has received by the emulsion electrospinning method. Prolonged yield of EGF upon the material destruction and its biological effect on the MCF7 cell line proliferation have been estimated using ELISA and iCEL-Ligence real-time cell analysis for respectively.

Gene-Activated Materials in Regenerative Dentistry: Narrative Review of Technology and Study Results

Treatment of a wide variety of defects in the oral and maxillofacial regions requires the use of innovative approaches to achieve best outcomes. One of the promising directions is the use of gene-activated materials (GAMs) that represent a combination of tissue engineering and gene therapy. This approach implies that biocompatible materials will be enriched with gene-carrying vectors and implanted into the defect site resulting in transfection of the recipient's cells and secretion of encoded therapeutic protein in situ. GAMs may be presented in various designs depending on the type of material, encoded protein, vector, and way of connecting the vector and the material. Thus, it is possible to choose the most suitable GAM design for the treatment of a particular pathology. The use of plasmids for delivery of therapeutic genes is of particular interest. In the present review, we aimed to delineate the principle of work and various designs of plasmid-based GAMs and to highlight results of experimental and clinical studies devoted to the treatment of periodontitis, jaw bone defects, teeth avulsion, and other pathologies in the oral and maxillofacial regions.