Application of Platelet Rich Fibrin in Tissue Engineering: Focus on Bone Regeneration.

Bone tissue engineering (BTE) is a strategy for reconstructing bone lesions, which is rapidly developing in response to higher demands for bone repairing. Recently, this method, along with the emergence of functionally graded, biocompatible and biodegradable materials, has been expanded. Moreover, scaffolds with chemical, physical and external patterns have induced bone regeneration. However, the maintenance of healthy bone and its regeneration in the human body needs a series of complex and accurate processes. Hence, many studies have been accompanied for reconstructing bone by using blood-derived biomaterials, especially platelet-rich fabricates. The most important reason for using platelet-rich formulations in bone regeneration is based on releasing growth factors from alpha granules in platelets, which can induce osteogenesis. Moreover, the presence of fibrin nano-fiber structures as a constituent can provide a good substrate for cell attachments. This study attempts to review the history, structure, and biology of platelet-rich fibrin (PRF) as well as in vitro, pre-clinical, and clinical studies on the use of PRF for bone regeneration.

Anti-IgE monoclonal antibodies as potential treatment in COVID-19.

Coronavirus disease 2019 (COVID-19) is associated with irreversible effects on vital organs, especially the respiratory and cardiac systems. While the immune system plays a key role in the survival of patients to viral infections, in COVID-19, there is a hyperinflammatory immune response evoked by all the immune cells, such as neutrophils, monocytes, and includes release of various cytokines, resulting in an exaggerated immune response, named cytokine storm. This severe, dysregulated immune response causes multi-organ damage, which eventually leads to high mortality. One of the most important components of hypersensitivity is immunoglobulin E (IgE), which plays a major role in susceptibility to respiratory infections and can lead to the activation of mast cells. There is also a negative association between IgE and IFN-α, which can reduce Toll-like receptor (TLR) nine receptor expression and TLR-7 signaling to disrupt IFN production. Moreover, anti-IgE drugs such as omalizumab reduces the severity and duration of COVID-19. In addition to its anti-IgE effect, omalizumab inhibits inflammatory cells such as neutrophils. Hence, blockade of IgE may have clinical utility as an immunotherapy for COVID-19.

The wound healing effect of polycaprolactone-chitosan scaffold coated with a gel containing Zataria multiflora Boiss. volatile oil nanoemulsions.

AIMS: Thymus plant is a very useful herbal medicine with various properties such as anti-inflammatory and antibacterial. Therefore, the properties of this plant have made this drug a suitable candidate for wound healing. In this study, hydroxypropyl methylcellulose (HPMC) gel containing Zataria multiflora volatile oil nanoemulsion (neZM) along with polycaprolactone/chitosan (PCL-CS) nanofibrous scaffold was used, and the effect of three experimental groups on the wound healing process was evaluated. The first group, HPMC gel containing neZM, the second group, PCL-CS nanofibers, and the third group, HPMC gel containing neZM and bandaged with PCL-CS nanofibers (PCL-CS/neZM). Wounds bandaged with common sterile gas were considered as control. METHODS: The nanoemulsion was synthesized by a spontaneous method and loaded into a hydroxypropyl methylcellulose (HPMC) gel. The DLS test investigated the size of these nanoemulsions. A PCL-CS nanofibrous scaffold was also synthesized by electrospinning method then SEM and contact angle tests investigated morphology and hydrophilicity/hydrophobicity of its surface. The animal study was performed on full-thickness skin wounds in rats, and the process of tissue regeneration in the experimental and control groups was evaluated by H&E and Masson's trichrome staining. RESULTS: The results showed that the nanoemulsion has a size of 225±9 nm and has an acceptable dispersion. The PCL-CS nanofibers synthesized by the electrospinning method also show non-beaded smooth fibers and due to the presence of chitosan with hydrophilic properties, have higher surface hydrophobicity than PCL fibers. The wound healing results show that the PCL-CS/neZM group significantly reduced the wound size compared to the other groups on the 7th, 14th, and 21st days. The histological results also show that the PCL-CS/neZM group could significantly reduce the parameters of edema, inflammation, and vascularity and increase the parameters of fibrosis, re-epithelialization, and collagen deposition compared to other groups on day 21. CONCLUSION: The results of this study show that the PCL-CS/neZM treatment can effectively improve wound healing.

Glucarpidase (carboxypeptidase G2): Biotechnological production, clinical application as a methotrexate antidote, and placement in targeted cancer therapy.

Patients receiving high-dose methotrexate (HDMTX) for malignancies are exposed to diverse complications, including nephrotoxicity, hepatotoxicity, mucositis, myelotoxicity, neurological symptoms, and death. Glucarpidase is a recombinant carboxypeptidase G2 (CPG2) that converts MTX into nontoxic metabolites. In this study, the role of vector type, gene optimization, orientation, and host on the expression of CPG2 is investigated. The effectiveness of various therapeutic regimens containing glucarpidase is classified and perspectives on the dose adjustment based on precision medicine are provided. Conjugation with cell-penetrating peptides, human serum albumin, and polymers such as PEG and dextran for delivery, higher stability, and production of the biobetter variants of CPG2 is highlighted. Conjugation of CPG2 to F(ab՜)2 or scFv antibody fragments against tumor-specific antigens and the corresponding prodrugs for tumor-targeted drug delivery using the antibody-directed enzyme prodrug therapy (ADEPT) is communicated. Trials to reduce the off-target effects and the possibility of repeated ADEPT cycles by adding pro-domains sensitive to tumor-overexpressed proteases, antiCPG2 antibodies, CPG2 mutants with immune-system-unrecognizable epitopes, and protective polymers are reported. Intracellular cpg2 gene expression by gene-directed enzyme prodrug therapy (GDEPT) and the concerns regarding the safety and transfection efficacy of the GDEPT vectors are described. A novel bifunctional platform using engineered CAR-T cell micropharmacies, known as Synthetic Enzyme-Armed KillER (SEAKER) cells, expressing CPG2 to activate prodrugs at the tumor niche is introduced. Taken together, integrated data in this review and recruiting combinatorial strategies in novel drug delivery systems define the future directions of ADEPT, GDEPT, and SEAKER cell therapy and the placement of CPG2 therein.

Preparation and In Vitro Osteogenic Evaluation of Biomimetic Hybrid Nanocomposite Scaffolds Based on Gelatin/Plasma Rich in Growth Factors (PRGF) and Lithium-Doped 45s5 Bioactive Glass Nanoparticles.

Bone tissue engineering is an emerging technique for repairing large bone lesions. Biomimetic techniques expand the use of organic-inorganic spongy-like nanocomposite scaffolds and platelet concentrates. In this study, a biomimetic nanocomposite scaffold was prepared using lithium-doped bioactive-glass nanoparticles and gelatin/PRGF. First, sol-gel method was used to prepare bioactive-glass nanoparticles that contain 0, 1, 3, and 5%wt lithium. The lithium content was then optimized based on antibacterial and MTT testing. By freeze-drying, hybrid scaffolds comprising 5, 10, and 20% bioglass were made. On the scaffolds, human endometrial stem cells (hEnSCs) were cultured for adhesion (SEM), survival, and osteogenic differentiation. Alkaline phosphatase activity and osteopontin, osteocalcin, and Runx2 gene expression were measured. The effect of bioactive-glass nanoparticles and PRGF on nanocomposites' mechanical characteristics and glass-transition temperature (T g) was also studied. An optimal lithium content in bioactive glass structure was found to be 3% wt. Nanoparticle SEM examination indicated grain deformation due to different sizes of lithium and sodium ions. Results showed up to 10% wt bioactive-glass and PRGF increased survival and cell adhesion. Also, Hybrid scaffolds revealed higher ALP-activity and OP, OC, and Runx2 gene expression. Furthermore, bioactive-glass has mainly increased ALP-activity and Runx2 expression, whereas PRGF increases the expression of OP and OC genes. Bioactive-glass increases scaffold modulus and T g continuously. Hence, the presence of both bioactive-glass and nanocomposite scaffold improves the expression of osteogenic differentiation biomarkers. Subsequently, it seems that hybrid scaffolds based on biopolymers, Li-doped bioactive-glass, and platelet extracts can be a good strategy for bone repair.

Doxorubicin-loaded Niosomes functionalized with gelatine and alginate as pH-responsive drug delivery system: A 3D printing approach.

Despite many efforts, breast cancer remains one of the deadliest cancers and its treatment faces challenges related to cancer drug side effects and metastasis. Combining 3D printing and nanocarriers has created new opportunities in cancer treatment. In this work, 3D-printed gelatin-alginate nanocomposites containing doxorubicin-loaded niosomes (Nio-DOX@GT-AL) were recruited as an advanced potential pH-sensitive drug delivery system. Morphology, degradation, drug release, flow cytometry, cell cytotoxicity, cell migration, caspase activity, and gene expression of nanocomposites and controls (Nio-DOX and Free-DOX) were evaluated. Results show that the obtained niosome has a spherical shape and size of 60-80 nm. Sustained drug release and biodegradability were presented by Nio-DOX@GT-AL and Nio-DOX. Cytotoxicity analysis revealed that the engineered Nio-DOX@GT-AL scaffold had 90 % cytotoxicity against breast cancer cells (MCF-7), whereas exhibited <5 % cytotoxicity against the non-tumor breast cell line (MCF-10A), which was significantly more than the antitumor effect of the control samples. Scratch-assay as an indicator cell migration demonstrated a reduction of almost 60 % of the covered surface. Gene expression could provide an explanation for the antitumor effect of engineered nanocarriers, which significantly reduced metastasis-promoting genes (Bcl2, MMP-2, and MMP-9), and significantly enhanced the expression and activity of genes that promote apoptosis (CASP-3, CASP-8, and CASP-9). Also, considerable inhibition of metastasis-associated genes (Bax and p53) was observed. Moreover, flow-cytometry data demonstrated that Nio-DOX@GT-AL decreased necrosis and enhanced apoptosis drastically. The findings of this research can confirm that employing 3D-printing and niosomal formulation can be an effective strategy in designing novel nanocarriers for efficient drug delivery applications.

3D-printing-assisted synthesis of paclitaxel-loaded niosomes functionalized by cross-linked gelatin/alginate composite: Large-scale synthesis and in-vitro anti-cancer evaluation.

Breast cancer is one of the most lethal cancers, especially in women. Despite many efforts, side effects of anti-cancer drugs and metastasis are still the main challenges in breast cancer treatment. Recently, advanced technologies such as 3D-printing and nanotechnology have created new horizons in cancer treatment. In this work, we report an advanced drug delivery system based on 3D-printed gelatin-alginate scaffolds containing paclitaxel-loaded niosomes (Nio-PTX@GT-AL). The morphology, drug release, degradation, cellular uptake, flow cytometry, cell cytotoxicity, migration, gene expression, and caspase activity of scaffolds, and control samples (Nio-PTX, and Free-PTX) were investigated. Results demonstrated that synthesized niosomes had spherical-like, in the range of 60-80 nm with desirable cellular uptake. Nio-PTX@GT-AL and Nio-PTX had a sustained drug release and were biodegradable. Cytotoxicity studies revealed that the designed Nio-PTX@GT-AL scaffold had <5 % cytotoxicity against non-tumorigenic breast cell line (MCF-10A) but showed 80 % cytotoxicity against breast cancer cells (MCF-7), which was considerably more than the anti-cancer effects of control samples. In migration evaluation (scratch-assay), approximately 70 % reduction of covered surface area was observed. The anticancer effect of the designed nanocarrier could be attributed to gene expression regulation, where a significant increase in the expression and activity of genes promoting apoptosis (CASP-3, CASP-8, and CASP-9) and inhibiting metastasis (Bax, and p53) and a remarkable decrease in metastasis-enhancing genes (Bcl2, MMP-2, and MMP-9) were observed. Also, flow cytometry results declared that Nio-PTX@GT-AL reduced necrosis and increased apoptosis considerably. The results of this study prove that employing 3D-printing and niosomal formulation is an effective approach in designing nanocarriers for efficient drug delivery applications.

COVID-19 and varicocele: The possible overlap factors and the common therapeutic approaches.

Varicocele is recognized as one of the main attributable causes of male infertility which can affect spermatogenesis by various pathophysiological mechanisms. Recent studies have identified oxidative stress and reduction in antioxidant, hyperthermia, hypoxia, hormonal dysfunction, and inflammatory conditions as major factors in the pathophysiology of varicocele, all of which have known direct associations with the coronavirus disease 2019 (COVID-19) and can significantly increase the risk of detrimental COVID-19-related outcomes. Emerging data have shown an association between COVID-19 and inflammation, overproduction of cytokine, and other pathophysiological processes. The present review, summarizes the current understanding of the pathophysiology of varicocele and investigates the potential correlation between the severity of COVID-19 and the varicocele disease. In addition, various possible treatments which can be effective in both diseases were examined. Despite numerous challenges associated with the prevalence of COVID-19 in healthcare systems in infected countries, special attention should be given to maintaining a high level of care for complex patients with a pre-existing disease such as varicocele and providing appropriate practical advice for optimal control of the COVID-19 disease.

The Potential Relationship Between Different Human Female Reproductive Disorders and Sperm Quality in Female Genital Tract.

Spermatozoa should travel throughout the female reproductive tract to reach its ultimate goal, fertilization of the oocyte. At the ejaculation moment, millions of sperm within a few milliliters of the ejaculate are deposited at the cranial segment of vagina and make their journey to the fertilization site. This is done by means of various factors, such as sperm motility, the uterine and fallopian tubes contractility, and the ciliary movement of the lining cells. During this migration, spermatozoa interact with the female microenvironment both physically and molecularly. In this regard, the quality of the environmental conditions may affect this interaction. Therefore, some alterations in women's genital tract microenvironment, such as conditions that occur in female reproductive disorders, may have detrimental effects on sperm reproductive function. In this review, human sperm migration through the female tract is described, and the potential effects of different reproductive disorders at reproductive organs, such as vagina, uterine cervix, uterus, fallopian tubes, and ovary on sperm survival and quality, are also argued. The understanding of those conditions that may impair sperm fertility in the female genital tract can provide a more accurate diagnosis of the causes of infertility in couples. This can ultimately lead to the discovery of effective treatment approaches.

An overview on tumor treating fields (TTFields) technology as a new potential subsidiary biophysical treatment for COVID-19.

COVID-19 pandemic situation has affected millions of people with tens of thousands of deaths worldwide. Despite all efforts for finding drugs or vaccines, the key role for the survival of patients is still related to the immune system. Therefore, improving the efficacy and the functionality of the immune system of COVID-19 patients is very crucial. The potential new, non-invasive, FDA-approved biophysical technology that could be considered in this regard is tumor treating fields (TTFields) based on an alternating electric field has great biological effects. TTFields have significant effects in improving the functionality of dendritic cell, and cytotoxic T-cells, and these cells have a major role in defense against viral infection. Hence, applying TTFields could help COVID-19 patients against infection. Additionally, TTFields can reduce viral genomic replication, by reducing the expressions of some of the vital members of DNA replication complex genes from the minichromosome maintenance family (MCMs). These genes not only are involved in DNA replication but it has also been proven that they have a crucial role in viral replication. Also, TTFields suppress the formation of the network of tunneling nanotubes (TNTs) which is knows as filamentous (F)-actin-rich tubular structures. TNTs have a critical role in promoting the spread of viruses through improving viral entry and acting as a protective agent for viral components from immune cells and even pharmaceuticals. Moreover, TTFields enhance autophagy which leads to apoptosis of virally infected cells. Thus, it can be speculated that using TTFields may prove to be a promising approach as a subsidiary treatment of COVID-19.

Li-Doped Bioactive Ceramics: Promising Biomaterials for Tissue Engineering and Regenerative Medicine.

Lithium (Li) is a metal with critical therapeutic properties ranging from the treatment of bipolar depression to antibacterial, anticancer, antiviral and pro-regenerative effects. This element can be incorporated into the structure of various biomaterials through the inclusion of Li chloride/carbonate into polymeric matrices or being doped in bioceramics. The biocompatibility and multifunctionality of Li-doped bioceramics present many opportunities for biomedical researchers and clinicians. Li-doped bioceramics (capable of immunomodulation) have been used extensively for bone and tooth regeneration, and they have great potential for cartilage/nerve regeneration, osteochondral repair, and wound healing. The synergistic effect of Li in combination with other anticancer drugs as well as the anticancer properties of Li underline the rationale that bioceramics doped with Li may be impactful in cancer treatments. The role of Li in autophagy may explain its impact in regenerative, antiviral, and anticancer research. The combination of Li-doped bioceramics with polymers can provide new biomaterials with suitable flexibility, especially as bio-ink used in 3D printing for clinical applications of tissue engineering. Such Li-doped biomaterials have significant clinical potential in the foreseeable future.