Osteochondral and bone tissue engineering scaffold prepared from Gallus var domesticus derived demineralized bone powder combined with gellan gum for medical application.

Osteochondral (OC) lesions can occur in the knee and ankle. Such lesions induce a fracture in the cartilage protecting the bone joints. Cartilage tissue shows limited self-regeneration ability, hence the tissue is avascular and lack of vascular innervation, while the bone is a unique organ with the capacity to self-repair of small defects. In this present study, we have prepared a scaffold using demineralized bone powder (DBP) extracted from Gallus gallus var domesticus (GD), and Gellan gum (GG) for OC tissue regeneration. They were characterized for their chemical, physical, mechanical and biological properties using different available techniques, in vitro bioactivity was performed in simulated body fluid for 14 days confirming the formation of bone-like apatite. The in vitro biocompatibility was analyzed using chondrocyte cells and osteogenic and chondrogenic marker gene expression using RT-PCR, in vivo experiments performed by implanting scaffold in rabbit and characterized by histology and immunofluorescent stainings. The obtained results indicated that the prepared pores scaffold was biocompatible, and promote OC regeneration and integration of newly formed tissues with the host tissues in a rabbit. The prepared 1% DBP/GG scaffold can be used as a potential and promising alternate material for OC regeneration.

Effect of different concentration of demineralized bone powder with gellan gum porous scaffold for the application of bone tissue regeneration.

The prevalence of bone-related diseases has increased, the population growth as a result of the aging phenomenon requires more effective treatments for regeneration of bone defect. Although an autogenous bone graft was used in traditional operation method, they are very inefficient in current bone defect surgery and very difficult to gather the required amount of bone for operation. It is becoming a gradually growing disease, hence there is a need for developing a new method for preparing biomimetic scaffolds. DBP (demineralized bone powder), a potent bone regeneration material, has a trace amount of ions and bone mineral component. Especially, GD (Gallus gallus var domesticus) DBP has a unique property, which has melanin, for strengthening bones, increasing ALP activity and bone mineralization, compared to other available biomaterials. For that reason, GD DBP was combined with GG (gellan gum). The material was characterized in vitro and in vivo rat model. The first priority in this work was given to assessing the attachment and proliferation rates of BMSCs following the in vivo experiment in rats. The results of 1% sample showed better osteogenic effects that can be used in clinical application after studying in larger animals for better bone regeneration and tissue engineering.

Engineering retinal pigment epithelial cells regeneration for transplantation in regenerative medicine using PEG/Gellan gum hydrogels.

Retinal pigment epithelium (RPE) plays an important role in maintaining normal function and visual function of the retina, and the degeneration of RPE causes various retinal degenerative diseases. Currently, there is a lack of effective treatment for this, and it is being studied to produce a suitable scaffold for cell transplantation. In this experiment, Polyethylene glycol (PEG)/Gellan Gum (GG) hydrogel was prepared by adding harmless PEG and gellan gum, which is a biocompatible, degradable and widely used in modern tissue engineering. PEG/GG hydrogel was prepared with 0, 1, 3, 5 wt% PEG/GG according to the concentration of PEG, and ARPE-19 cells were used to confirm the cell attachment environment. As a result, it showed superior biocompatibility (>90%), cell adhesion and improved cell growth compared to gellan gum hydrogel. In addition, RT-PCR was used to confirm RPE-specific gene expression, and the result showed that it was positively influenced. As a result, it was observed that PEG/GG hydrogel promotes retinal regeneration compared to pure gellan gum. 3 wt% PEG/GG could be used as an alternative for retinal regeneration.

Enhanced retinal pigment epithelium (RPE) regeneration using curcumin/alginate hydrogels: In vitro evaluation.

The retinal pigment epithelium (RPE) plays a significant role in retaining structural integrity of eye. Factors such as reduction in cell regeneration due to aging and physical injury pose a major hurdle in RPE regeneration. In this study, we exploited the use of alginate (AGT) incorporated with Curcumin (CCI) forming a hydrogel based system CCI/AGT. The fabricated hydrogel could anchor RPE cell in it. In vitro cell analysis revealed that the CCI/AGT hydrogel shows good biocompatibility, enhanced cell growth ability and higher ECM formation compared to the pure AGT hydrogel. In particular, the presence of CCI in the hydrogels enhances the cells proliferation of the 23% respect to the pure alginate. Also the expression of crucial genes for retina functions and matrix production were positively affected by CCI presence, with an increment of 45% for RPE65, 32% for CRALBP and 26% for Collagen type 1. In vitro tests demonstrated the potential application of CCI/AGT hydrogels for transplantation under the sub-retinal space acting as a cell delivery vehicle and also their capability to provide an appropriate environment for RPE regeneration. These results suggest that CCI/AGT hydrogel could be translated into a potential surgical graft for biological implantation of retinal tissue engineering.

Current status and regulatory perspective of chimeric antigen receptor-modified T cell therapeutics.

Chimeric antigen receptor-modified T cells (CAR-T) have emerged as a new modality for cancer immunotherapy due to their potent efficacy against terminal cancers. CAR-Ts are reported to exert higher efficacy than monoclonal antibodies and antibody-drug conjugates, and act via mechanisms distinct from T cell receptor-engineered T cells. These cells are constructed by transducing genes encoding fusion proteins of cancer antigen-recognizing single-chain Fv linked to intracellular signaling domains of T cell receptors. CAR-Ts are classified as first-, second- and third-generation, depending on the intracellular signaling domain number of T cell receptors. This review covers the current status of CAR-T research, including basic proof-of-concept investigations at the cell and animal levels. Currently ongoing clinical trials of CAR-T worldwide are additionally discussed. Owing to the lack of existing approved products, several unresolved concerns remain with regard to safety, efficacy and manufacturing of CAR-T, as well as quality control issues. In particular, the cytokine release syndrome is the major side-effect impeding the successful development of CAR-T in clinical trials. Here, we have addressed the challenges and regulatory perspectives of CAR-T therapy.

Alarmin IL-33 acts as an immunoadjuvant to enhance antigen-specific tumor immunity.

Studies of interleukin (IL)-33 reveal a number of pleiotropic properties. Here, we report that IL-33 has immunoadjuvant effects in a human papilloma virus (HPV)-associated model for cancer immunotherapy where cell-mediated immunity is critical for protection. Two biologically active isoforms of IL-33 exist that are full-length or mature, but the ability of either isoform to function as a vaccine adjuvant that influences CD4 T helper 1 or CD8 T-cell immune responses is not defined. We showed that both IL-33 isoforms are capable of enhancing potent antigen-specific effector and memory T-cell immunity in vivo in a DNA vaccine setting. In addition, although both IL-33 isoforms drove robust IFN-γ responses, neither elevated secretion of IL-4 or immunoglobulin E levels. Further, both isoforms augmented vaccine-induced antigen-specific polyfunctional CD4(+) and CD8(+) T-cell responses, with a large proportion of CD8(+) T cells undergoing plurifunctional cytolytic degranulation. Therapeutic studies indicated that vaccination with either IL-33 isoform in conjunction with an HPV DNA vaccine caused rapid and complete regressions in vivo. Moreover, IL-33 could expand the magnitude of antigen-specific CD8(+) T-cell responses and elicit effector-memory CD8(+) T cells. Taken together, our results support the development of these IL-33 isoforms as immunoadjuvants in vaccinations against pathogens, including in the context of antitumor immunotherapy.