Adipose Derived Stem Cells for Corneal Wound Healing after Laser Induced Corneal Lesions in Mice

Characterization of 3D Organotypic Culture of Mouse Adipose-Derived Stem Cells

Although stem cells are a promising avenue for harnessing the potential of adipose tissue, conventional two-dimensional (2D) culture methods have limitations. This study explored the use of three-dimensional (3D) cultures to preserve the regenerative potential of adipose-derived stem cells (ADSCs) and investigated their cellular properties. Flow cytometric analysis revealed significant variations in surface marker expressions between the two culture conditions. While 2D cultures showed robust surface marker expressions, 3D cultures exhibited reduced levels of CD44, CD90.2, and CD105. Adipogenic differentiation in 3D organotypic ADSCs faced challenges, with decreased organoid size and limited activation of adipogenesis-related genes. Key adipocyte markers, such as lipoprotein lipase (LPL) and adipoQ, were undetectable in 3D-cultured ADSCs, unlike positive controls in 2D-cultured mesenchymal stem cells (MSCs). Surprisingly, 3D-cultured ADSCs underwent mesenchymal-epithelial transition (MET), evidenced by increased E-cadherin and EpCAM expression and decreased mesenchymal markers. This study highlights successful ADSC organoid formation, notable MSC phenotype changes in 3D culture, adipogenic differentiation challenges, and a distinctive shift toward an epithelial-like state. These findings offer insights into the potential applications of 3D-cultured ADSCs in regenerative medicine, emphasizing the need for further exploration of underlying molecular mechanisms.

Corneal wound healing following infrared laser irradiation at the wavelengths of 1.319 and 10.6 μm

OBJECTIVES

To investigate the wound healing of rabbit cornea following infrared laser irradiations at the wavelengths of 1.319 and 10.6 μm.

MATERIALS AND METHODS

Twelve New Zealand rabbits were selected to establish a corneal injury model. The right and left eyes were irradiated with a neodymium-doped yttrium aluminum garnet laser at the wavelength of 1.319 μm (140 J/cm2 ) for 0.7 s and a CO2 laser at the wavelength of 10.6 μm (5.94 J/cm2 ) for 0.14 s, respectively. The incident spot diameter was 3 mm. Optical coherence tomography (OCT) was used to monitor injuries at 0 h, 0.5 h, 1 h, 3 h, 6 h, 12 h, 18 h, 24 h, 30 h, 36 h, 42 h, 48 h, 54 h, 60 h, 66 h, 3 d, 7 d, 14 d, 28 d, 3 m, and 6 m postexposure. Meanwhile, slit-lamp microscopy and histopathology were performed at 6 h, 24 h, 3 d, 7 d, 14 d, 28 d, 3 m, and 6 m postexposure.

RESULTS

After the two types of infrared laser injuries, distinct white circular lesions on the corneal surface were directly observed. Deeper corneal injury, more severe edema, and faster migration of new epithelium were found for the wavelength of 1.319 μm, compared to the wavelength of 10.6 μm.

CONCLUSIONS

OCT combined with histopathology and slit-lamp microscopy can clearly observe the dynamic process of corneal wound healing after infrared laser irradiation. The damage characteristics for the two different wavelengths were visibly different, but the whole wound healing process was similar. The obtained results may provide references for the diagnosis, treatment, and evaluation of laser-induced damages.

Corneal Epithelial Development and the Role of Induced Pluripotent Stem Cells for Regeneration

Severe corneal disorders due to infective aetiologies, trauma, chemical injuries, and chronic cicatricial inflammations, are among vision-threatening pathologies leading to permanent corneal scarring. The whole cornea or lamellar corneal transplantation is often used as a last resort to restore vision. However, limited autologous tissue sources and potential adverse post-allotransplantation sequalae urge the need for more robust and strategic alternatives. Contemporary management using cultivated corneal epithelial transplantation has paved the way for utilizing stem cells as a regenerative potential. Humaninduced pluripotent stem cells (hiPSCs) can generate ectodermal progenitors and potentially be used for ocular surface regeneration. This review summarizes the process of corneal morphogenesis and the signaling pathways underlying the development of corneal epithelium, which is key to translating the maturation and differentiation process of hiPSCs in vitro. The current state of knowledge and methodology for driving efficient corneal epithelial cell differentiation from pluripotent stem cells are highlighted.

Future regenerative therapies for corneal disease

PURPOSE OF REVIEW

To highlight the progress and future direction of stem-cell based regenerative therapies for the treatment of corneal disease.

RECENT FINDINGS

Corneal stem cell-based therapies, such as limbal stem cell transplantation, corneal stromal stem cell transplantation, endothelial stem cell transplantation, and stem cell-derived extracellular vesicles have demonstrated promising results in the laboratory. Although most are still in preclinical development or early phase clinical trials, these stem cell-based therapies hold potential to facilitate tissue regeneration, restore native function, and inhibit pathologic disease processes such as fibrosis, inflammation, and neovascularization.

SUMMARY

Stem cell-based therapy offers a promising therapeutic option that can circumvent several of the challenges and limitations of traditional surgical treatment. This concise review summarizes the progress in stem-cell based therapies for corneal diseases along with their history, underlying mechanisms, limitations, and future areas for development.

Adipose Stem Cells in Modern-Day Ophthalmology

Stem cells (SCs) have evolved as an interesting and viable factor in ophthalmologic patient care in the past decades. SCs have been classified as either embryonic, mesenchymal, tissue-specific, or induced pluripotent cells. Multiple novel management techniques and clinical trials have been established to date. While available publications are predominantly animal-model-based, significant material is derived from human studies and case-selected scenarios. This possibility of explanting cells from viable tissue to regenerate/repair damaged tissue points to an exciting future of therapeutic options in all fields of medicine, and ophthalmology is surely not left out. Adipose tissue obtained from lipo-aspirates has been shown to produce mesenchymal SCs that are potentially useful in different body parts, including the oculo-visual system. An overview of the anatomy, physiology, and extraction process for adipose-tissue-derived stem cells (ADSC) is important for better understanding the potential therapeutic benefits. This review examines published data on ADSCs in immune-modulatory, therapeutic, and regenerative treatments. We also look at the future of ADSC applications for ophthalmic patient care. The adverse effects of this relatively novel therapy are also discussed.

Cellular Therapeutics for Chronic Wound Healing: Future for Regenerative Medicine

Chronic wounds are associated with significant morbidity and mortality, which demand long-term effective treatment and represent a tremendous financial strain on the global healthcare systems. Regenerative medicines using stem cells have recently become apparent as a promising approach and are an active zone of investigation. They hold the potential to differentiate into specific types of cells and thus possess self-renewable, regenerative, and immune-modulatory effects. Furthermore, with the rise of technology, various cell therapies and cell types such as Bone Marrow and Adipose-derived Mesenchymal Cell (ADMSC), Endothelial Progenitor Cells (EPCs), Embryonic Stem Cells (ESCs), Mesenchymal Stem Cell (MSCs), and Pluripotent Stem Cells (PSCs) are studied for their therapeutic impact on reparative processes and tissue regeneration. Cell therapy has proven to have substantial control over enhancing the quality and rate of skin regeneration and wound restoration. The literature review brings to light the mechanics of wound healing, abnormalities resulting in chronic wounds, and the obstacles wound care researchers face, thus exploring the multitude of opportunities for potential improvement. Also, the review is focused on providing particulars on the possible cell-derived therapeutic choices and their associated challenges in healing, in the context of clinical trials, as solutions to these challenges will provide fresh and better future opportunities for improved study design and therefore yield a substantial amount of data for the development of more specialized treatments.

Synthetic Heparan Sulfate Mimetic Polymer Enhances Corneal Nerve Regeneration and Wound Healing after Experimental Laser Ablation Injury in Mice

(1) Background: Abnormal corneal wound healing compromises visual acuity and can lead to neuropathic pain. Conventional treatments usually fail to restore the injured corneal tissue. In this study, we evaluated the effectiveness of a synthetic heparan sulfate mimetic polymer (HSmP) in a mouse model of corneal wound healing. (2) Methods: A surgical laser ablation affecting the central cornea and subbasal nerve plexus of mice was used as a model of the wound-healing assay. Topical treatment with HSmP was contrasted to its vehicle and a negative control (BSS). Corneal repair was studied using immunofluorescence to cell proliferation (Ki67), apoptosis (TUNEL assay), myofibroblast transformation (αSMA), assembly of epithelial cells (E-cadherin) and nerve regeneration (β-tubulin III). (3) Results: At the end of the treatment, normal epithelial cytoarchitecture and corneal thickness were achieved in HSmP-treated animals. HSmP treatment reduced myofibroblast occurrence compared to eyes irrigated with vehicle (p < 0.01) or BSS (p < 0.001). The HSmP group showed 50% more intraepithelial nerves than the BSS or vehicle groups. Only HSmP-treated corneas improved the visual quality to near transparent. (4) Conclusions: These results suggest that HSmP facilitates the regeneration of the corneal epithelium and innervation, as well as restoring transparency and reducing myofibroblast scarring after laser experimental injury.

Application Prospect and Preliminary Exploration of GelMA in Corneal Stroma Regeneration

Corneal regeneration has become a prominent study area in recent decades. Because the corneal stroma contributes about 90% of the corneal thickness in the corneal structure, corneal stromal regeneration is critical for the treatment of cornea disease. Numerous materials, including deacetylated chitosan, hydrophilic gel, collagen, gelatin methacrylate (GelMA), serine protein, glycerol sebacate, and decellularized extracellular matrix, have been explored for keratocytes regeneration. GelMA is one of the most prominent materials, which is becoming more and more popular because of its outstanding three-dimensional scaffold structure, strong mechanics, good optical transmittance, and biocompatibility. This review discussed recent research on corneal stroma regeneration materials and related GelMA.

Regenerative therapy for the Cornea

The cornea is the outmost layer of the eye, unique in its transparency and strength. The cornea not only transmits the light essential for vision, also refracts light, giving focus to images. Each of the three layers of the cornea has properties essential for the function of vision. Although the epithelium can often recover from injury quickly by cell division, loss of limbal stem cells can cause severe corneal surface abnormalities leading to corneal blindness. Disruption of the stromal extracellular matrix and loss of cells determining this structure, the keratocytes, leads to corneal opacity. Corneal endothelium is the inner part of the cornea without self-renewal capacity. It is very important to maintain corneal dehydration and transparency. Permanent damage to the corneal stroma or endothelium can be effectively treated by corneal transplantation; however, there are drawbacks to this procedure, including a shortage of donors, the need for continuing treatment to prevent rejection, and limits to the survival of the graft, averaging 10-20 years. There exists a need for new strategies to promote regeneration of the stromal structure and restore vision. This review highlights critical contributions in regenerative medicine with the aim of corneal reconstruction after injury or disease. These approaches include corneal stromal stem cells, corneal limbal stem cells, embryonic stem cells, and other adult stem cells, as well as induced pluripotent stem cells. Stem cell-derived trophic factors in the forms of secretomes or exosomes for corneal regeneration are also discussed. Corneal sensory nerve regeneration promoting corneal transparency is discussed. This article provides description of the up-to-date options for corneal regeneration and presents exciting possible avenues for future studies toward clinical applications for corneal regeneration.

Stem cell therapy in ocular pathologies in the past 20 years

Stem cell therapies are successfully used in various fields of medicine. This new approach of research is also expanding in ophthalmology. Huge investments, resources and important clinical trials have been performed in stem cell research and in potential therapies. In recent years, great strides have been made in genetic research, which permitted and enhanced the differentiation of stem cells. Moreover, the possibility of exploiting stem cells from other districts (such as adipose, dental pulp, bone marrow stem cells, etc.) for the treatment of ophthalmic diseases, renders this topic fascinating. Furthermore, great strides have been made in biomedical engineering, which have proposed new materials and three-dimensional structures useful for cell therapy of the eye. The encouraging results obtained on clinical trials conducted on animals have given a significant boost in the creation of study protocols also in humans. Results are limited to date, but clinical trials continue to evolve. Our attention is centered on the literature reported over the past 20 years, considering animal (the most represented in literature) and human clinical trials, which are limiting. The aim of our review is to present a brief overview of the main types of treatments based on stem cells in the field of ophthalmic pathologies.

Xeno-free approach for the expansion of human adipose derived mesenchymal stem cells for ocular therapies

To restore corneal transparency and vision loss after an injury on the ocular surface, the use of human stem cells from different origins has been recently proposed. Mesenchymal stem cells (MSCs) seem to be an appropriate adult source of autologous stem cells due to their accessibility, high proliferation rate, and multipotent capacity. In this work, we developed a simple culture system to prepare a graft based on a fibrin membrane seeded with human MSCs. A commercial kit, PRGF Endoret®, was used to prepare both, the growth factors used as culture media supplement and the fibrin membrane grafts. Adipose-derived MSCs (Ad-MSCs) were expanded, characterised by flow cytometry and their multilineage differentiation potential confirmed by inducing adipogenesis, osteogenesis and chondrogenesis. Ad-MSCs seeded on the fibrin membranes were grafted onto athymic mice showing good biocompatibility with no adverse reactions observed during the follow up period. These findings support the assumption that a system in which all the biological components (cells, grow factors and carrier) are autologous, could potentially be used for future ex vivo expansion of Ad-MSCs to treat ocular conditions such as an inflammatory milieu, traumatic scars and loss of the regenerative capacity of the corneal epithelium that compromise the quality of vision.

Adipose-derived mesenchymal stromal cells promote corneal wound healing by accelerating the clearance of neutrophils in cornea

The dome-shaped cornea is a transparent, non-vascularized, and epithelialized highly organized tissue. Physical and chemical injuries may trigger corneal wound healing (CWH) response and result in neovascularization that impairs the visual function. CWH involves not only migration, proliferation, and differentiation of the cells in different layers of cornea, but also the mobilization of immune cells. We demonstrated here that human adipose-derived mesenchymal stromal cells (ADSCs) could effectively inhibit neovascularization during ethanol-induced injury in mouse cornea. Importantly, we found that while neutrophils are essential for CWH, excessive and prolonged neutrophil retention during the granulation stage contributes to neovascularization. ADSCs were found to promote the clearance of neutrophils in the cornea during the granulation stage, likely via increasing the reverse transendothelial cell migration of CXCR4high neutrophils from cornea to the lung. Our results demonstrate that ADSCs are effective in treating CWH-induced neovascularization and modulation of neutrophil clearance could be novel strategies for better vision recovery after injury.

Insights into the role of adipose-derived stem cells: Wound healing and clinical regenerative potential

The incidence of acute and chronic wound diseases is rising due to various reasons. With complicated pathogenesis, long course, difficult treatment and high disability, wound diseases have become a major burden for patients, their families, and society. Therefore, the focus of research is to identify new ideas and methods for treatment. Fat grafting has gained increased attention because of its effectiveness in wound treatment, and further analysis has uncovered that the stem cells derived from fat may be the main factor affecting wound healing. We summarize the function of adipose stem cells and analyze their possible mechanisms in tissue repair, helping to provide new ideas for the treatment of wound healing.

Hypothermically Stored Adipose-Derived Mesenchymal Stromal Cell Alginate Bandages Facilitate Use of Paracrine Molecules for Corneal Wound Healing

Adipose-derived mesenchymal stromal cells (Ad-MSCs) may alleviate corneal injury through the secretion of therapeutic factors delivered at the injury site. We aimed to investigate the therapeutic factors secreted from hypothermically stored, alginate-encapsulated Ad-MSCs’ bandages in in vitro and in vivo corneal wounds. Ad-MSCs were encapsulated in 1.2% w/v alginate gels to form bandages and stored at 15 °C for 72 h before assessing cell viability and co-culture with corneal scratch wounds. Genes of interest, including HGF, TSG-6, and IGF were identified by qPCR and a human cytokine array kit used to profile the therapeutic factors secreted. In vivo, bandages were applied to adult male mice corneas following epithelial debridement. Bandages were shown to maintain Ad-MSCs viability during storage and able to indirectly improve corneal wound healing in vivo. Soluble protein concentration and paracrine factors such as TSG-6, HGF, IL-8, and MCP-1 release were greatest following hypothermic storage. In vivo, Ad-MSCs bandages-treated groups reduced immune cell infiltration when compared to untreated groups. In conclusion, bandages were shown to maintain Ad-MSCs ability to produce a cocktail of key therapeutic factors following storage and that these soluble factors can improve in vitro and in vivo corneal wound healing.

Topical cell-free conditioned media harvested from adipose tissue-derived stem cells promote recovery from corneal epithelial defects caused by chemical burns

Corneal chemical burns can lead to blindness following serious complications. As most of these complications are caused by failure of reepithelization during the acute phase, treatment at this stage is critical. Although there have been some studies on corneal injury recovery using adipose tissue-derived stem cells (ADSCs), none has reported the effect of topical cell-free conditioned culture media (CM) derived from ADSCs on corneal epithelial regeneration. Here, the best conditions for CM were selected and used for in vitro and in vivo experiments. Corneal burn in rats was induced using 100% alcohol. The chosen CM was administered to corneal burn rats (CM-treated [CT] group) four times a day for three days and this group was compared with the normal control and corneal burn (CB) groups. Biomicroscopic fluorescence images and the actual physical corneas were taken over time and used for analysis. mRNA levels of hepatocyte growth factor and epidermal growth factor (EGF) were significantly increased, whereas those of vascular endothelial growth factor, interleukin (IL)-1β, IL-6, IL-10, and matrix metalloproteinase-9 were significantly decreased in the CT group compared with those in the CB group. The numbers of proliferating cell nuclear antigen- and zonular occludens-1-positive cells in the CT group were significantly higher than those in the CB group. The macrophage-infiltrating corneas in the CT group expressed significantly more of the M2 marker arginase than corneas in the CB group. Optimal CM (× 0.5 concentration) treatment significantly accelerated the migration of corneal epithelial cells and induced upregulation of the expression of IL-6, EGF, and C-X-C chemokine receptor type 4 mRNAs. Overall, in this study, topical administration of cell-free CM promoted regeneration of the corneal epithelium after induction of chemical burns.

Recent developments in regenerative ophthalmology

Regenerative medicine (RM) is one of the most promising disciplines for advancements in modern medicine, and regenerative ophthalmology (RO) is one of the most active fields of regenerative medicine. This review aims to provide an overview of regenerative ophthalmology, including the range of tools and materials being used, and to describe its application in ophthalmologic subspecialties, with the exception of surgical implantation of artificial tissues or organs (e.g., contact lens, artificial cornea, intraocular lens, artificial retina, and bionic eyes) due to space limitations. In addition, current challenges and limitations of regenerative ophthalmology are discussed and future directions are highlighted.

Development and Optimization of Freeze-Dried Eye Drops Derived From Plasma Rich in Growth Factors Technology

Purpose

To investigate whether plasma rich in growth factors (PRGF) eye drops maintain their biological potential after a freeze drying process. The addition of a lyoprotectant like trehalose was also evaluated.

Methods

Blood from three healthy donors was collected to obtain eye drops by PRGF technology. The resultant eye drops were divided in four groups: PRGF, freeze-dried PRGF (PRGF lyo), and PRGF lyophilized mixed with 2,5% trehalose (PRGF lyo+2.5T) or 5% trehalose (PRGF lyof+5T). Chemical and biological characteristics were evaluated. Photorefractive keratectomy was performed on C57BL/6 mice which were divided in three treatment groups: control, PRGF, and PRGF lyo. Corneal wound healing and haze formation were evaluated macroscopically. Eyes were collected at 1, 2, 3, and 7 days after surgery, and were processed for histologic studies.

Results

The pH values of PRGF samples increased significantly after the lyophilization process. Osmolarity levels increased significantly in PRGF samples mixed with trehalose in comparison with PRGF samples without protectants. The freeze drying process maintained growth factors levels as well as the biological properties of PRGF eye drops even without the use of lyoprotectants. PRGF lyo treatment significantly decreased the re-epithelialization time and haze formation in photorefractive keratectomy-treated corneas regarding PRGF and control groups. Furthermore, the PRGF lyo group significantly decreased the number of smooth muscle actin-positive cells in comparison with the control group at each time of the study and at days 2 and 3 in the PRGF group.

Conclusions

The freeze drying process preserves the protein and growth factor content as well as the biological properties of PRGF eye drops, even without the use of protectants. Freeze-dried PRGF eye drops accelerate corneal tissue regeneration after photorefractive keratectomy in comparison with the control group.

Translational Relevance

Our study shows the feasibility to preserve the biological capability of PRGF eye drops as freeze-dried formulation, avoiding the addition of protectants.

Cellular therapy of corneal epithelial defect by adipose mesenchymal stem cell-derived epithelial progenitors

Background

Persistent epithelial defects (PED), associated with limbal stem cell deficiency (LSCD), require ocular surface reconstruction with a stable corneal epithelium (CE). This study investigated CE reformation using human adipose mesenchymal stem cells (ADSC), which derived epithelial progenitors via mesenchymal-epithelial transition (MET).

Methods

STEMPRO human ADSC were cultured with specific inhibitors antagonizing glycogen synthase kinase-3 and transforming growth factor-β signaling, followed by culture under a defined progenitor cell targeted-epithelial differentiation condition to generate epithelial-like cells (MET-Epi), which were characterized for cell viability, mesenchymal, and epithelial phenotypes using immunofluorescence and flow cytometry. Tissue-engineered (TE) MET-Epi cells on fibrin gel were transplanted to corneal surface of the rat LSCD model caused by alkali injury. Epithelial healing, corneal edema, and haze grading, CE formation were assessed by fluorescein staining, slit lamp bio-microscopy, anterior segment optical coherence tomography, and immunohistochemistry.

Results

CD73^high/CD90^high/CD105^high/CD166^high/CD14^negative/CD31^negative human ADSC underwent MET, giving viable epithelial-like progenitors expressing δNp63, CDH1 (E-cadherin), epidermal growth factor receptor, integrin-β4, and cytokeratin (CK)-5, 9. Under defined epithelial differentiation culture, these progenitors generated MET-Epi cells expressing cell junction proteins ZO1 and occludin. When transplanted onto rat corneal surface with LSCD-induced PED, TE-MET-Epi achieved more efficient epithelial healing, suppressed corneal edema, and opacities, when compared to corneas without treatment or transplanted with TE-ADSC. CE markers (CK3, 12, and CDH1) were expressed on TE-MET-Epi-transplanted corneas but not in other control groups.

Conclusion

Human ADSC-derived epithelial-like cells, via MET, recovered the CE from PED associated with LSCD. ADSC can be a viable adult stem cell source for potential autologous epithelial cell-based therapy for corneal surface disorders.

Secretome of Adipose Tissue-Derived Stem Cells (ASCs) as a Novel Trend in Chronic Non-Healing Wounds: An Overview of Experimental In Vitro and In Vivo Studies and Methodological Variables

Wound healing is a complex process with a linear development that involves many actors in a multistep timeline commonly divided into four stages: Hemostasis, inflammation, proliferation, and remodeling. Chronic non-healing wounds fail to progress beyond the inflammatory phase, thus precluding the next steps and, ultimately, wound repair. Many intrinsic or extrinsic factors may contribute to such an occurrence, including patient health conditions, age-related diseases, metabolic deficiencies, advanced age, mechanical pressure, and infections. Great interest is being focused on the adipose tissue-derived stem cell’s (ASC) paracrine activity for its potential therapeutic impact on chronic non-healing wounds. In this review, we summarize the results of in vitro and in vivo experimental studies on the pro-wound healing effects of ASC-secretome and/or extracellular vesicles (EVs). To define an overall picture of the available literature data, experimental conditions and applied methodologies are described as well as the in vitro and in vivo models chosen in the reported studies. Even if a comparative analysis of the results obtained by the different groups is challenging due to the large variability of experimental conditions, the available findings are undoubtedly encouraging and fully support the use of cell-free therapies for the treatment of chronic non-healing wounds.

Effectiveness of Low-Level Laser Therapy during Tooth Movement: A Randomized Clinical Trial

The present study evaluated the effects of low-level laser therapy (LLLT) by means of a diode laser in accelerating orthodontic tooth movement (OTM). After extraction of the first upper premolars for orthodontic purpose, 82 maxillary canines which needed distalization were analyzed in 41 enrolled patients (21 males, 20 females, mean age 13.4 ± 2.1 years). On all experimental sites, an orthodontic force of 50/N was applied by a nickel-titanium (NiTi) closed coil spring (G&H, Franklin, IN, USA) in order to obtain the space closure. Using a split mouth randomized design, the test side was treated using a diode laser (Wiser Laser Doctor Smile, Brendola, Italy) operating at 810 nm wavelength in continuous wave mode at both the buccal and palatal side on three points/side (distal, medial and mesial) (1 W output power, continuous wave of 66.7 J/cm², energy density of 8 J) at baseline and at 3, 7, and 14 days and every 15 days until the space closed. On the control side, the opposite selected canine was treated only using orthodontic traction. The primary outcome chosen was the overall time needed to complete the levelling and closing space, measured on a study cast. The secondary outcome chosen was the evaluation of pain levels related to tooth traction, using a Visual Analogue Scale (VAS), recorded at 3, 7, and 14 days after treatments. The mean space closures of the maxillary canines were comparable between groups [Test, 4.56 mm (95% CI 3.9-4.8); Control, 4.49 mm (95% CI 3.8-4.7), p = 0.456]. The laser group yielded less mean time [84.35 ± 12.34 days (95% CI 79.3-86)] to accomplish space closure compared to the control group [97.49 ± 11.44 days (91.7-102.3)] (p < 0.001). The test side showed a significant reduction in the average range of dental pain at 3 [Test, 5.41 (95% CI 5.1-5.6); Control, 7.23 (95% CI 6.9-7.6), p < 0.001], 7 [Test, 4.12 (95% CI 3.8-4.7); Control, 5.79 (95% CI 5.4-5.8), p < 0.001], and at 14 days [Test, 2.31 (95% CI 1.8-2.3); Control, 3.84 (95% CI 3.3-4.2), p < 0.001] after treatment (p < 0.001). This study demonstrates that the use of LLLT therapy was effective in accelerating tooth movement and reducing pain levels related to OTM.

Revisiting the Advances in Isolation, Characterization and Secretome of Adipose-Derived Stromal/Stem Cells

Adipose-derived stromal/stem cells (ASCs) seems to be a promising regenerative therapeutic agent due to the minimally invasive approach of their harvest and multi-lineage differentiation potential. The harvested adipose tissues are further digested to extract stromal vascular fraction (SVF), which is cultured, and the anchorage-dependent cells are isolated in order to characterize their stemness, surface markers, and multi-differentiation potential. The differentiation potential of ASCs is directed through manipulating culture medium composition with an introduction of growth factors to obtain the desired cell type. ASCs have been widely studied for its regenerative therapeutic solution to neurologic, skin, wound, muscle, bone, and other disorders. These therapeutic outcomes of ASCs are achieved possibly via autocrine and paracrine effects of their secretome comprising of cytokines, extracellular proteins and RNAs. Therefore, secretome-derivatives might offer huge advantages over cells through their synthesis and storage for long-term use. When considering the therapeutic significance and future prospects of ASCs, this review summarizes the recent developments made in harvesting, isolation, and characterization. Furthermore, this article also provides a deeper insight into secretome of ASCs mediating regenerative efficacy.