Transplantation Of Fibroblasts Research Articles

Autologous Cultured Fibroblast Cell Therapy for Treatment of Stria Alba

Abstract Background There is growing evidence showing that human autologous cultured fibroblast transplantation is a safe alternative treatment to prevent and reduce the structural changes in aging skin. Previous data indicate that injections of autologous fibroblasts increase collagen formation, accompanied by a concomitant increase in thickness and density of dermal collagen. our study will highlight the technique of autologous cultured fibroblast and it is indication for treatment of stria alba and this wasn't done before. Objective To evaluate the efficacy and safety of autologous cultured fibroblast for improvement of stria alba. Patients and Methods The present study included 15 patients a with stria alba. The study was approved by the Research Ethical Committee, Faculty of Medicine, Ain Shams University and fulfilled all the ethical aspects required in human research. All patients received full information about description of the procedure of treatment, possible side effects, photo documentation and they all provided written consent. the patients were injected intradermally by autologous fibroblast suspension at 2 weeks intervals with total of 3 sessions. Results Before autologous fibroblast injection (baseline), the width of stria ranged from 4-17.4 mm (mean 8.18 ± 3.85). After treatment at 3rd month, stria ranged from 2.9 – 14.8 (mean 7.17 ± 3.26) and at the 6th month ranged from 2.9 – 14.8 (mean 7.16 ± 3.27). Comparison of width of stria before versus after injection showed non significant difference (p value 0.062)On contrast, the histopathological examination by H&E, Masson Trichome and Orcein stain a showed significant improvement in the form of increased epidermal thickness, better collagen arrangement and thickness and increased elastic fibers contents. Conclusion Autologous fibroblast injection in treatment of stria alba may have promising results in the future especially if combined with other tretment modalities.

The Development of an Advanced Model for Multilayer Human Skin Reconstruction In Vivo.

Human skin reconstruction on immune-deficient mice has become indispensable for in vivo studies performed in basic research and translational laboratories. Further advancements in making sustainable, prolonged skin equivalents to study new therapeutic interventions rely on reproducible models utilizing patient-derived cells and natural three-dimensional culture conditions mimicking the structure of living skin. Here, we present a novel step-by-step protocol for grafting human skin cells onto immunocompromised mice that requires low starting cell numbers, which is essential when primary patient cells are limited for modeling skin conditions. The core elements of our method are the sequential transplantation of fibroblasts followed by keratinocytes seeded into a fibrin-based hydrogel in a silicone chamber. We optimized the fibrin gel formulation, timing for gel polymerization in vivo, cell culture conditions, and seeding density to make a robust and efficient grafting protocol. Using this approach, we can successfully engraft as few as 1.0 × 106 fresh and 2.0 × 106 frozen-then-thawed keratinocytes per 1.4 cm2 of the wound area. Additionally, it was concluded that a successful layer-by-layer engraftment of skin cells in vivo could be obtained without labor-intensive and costly methodologies such as bioprinting or engineering complex skin equivalents. Key features • Expands upon the conventional skin chamber assay method (Wang et al., 2000) to generate high-quality skin grafts using a minimal number of cultured skin cells. • The proposed approach allows the use of frozen-then-thawed keratinocytes and fibroblasts in surgical procedures. • This system holds promise for evaluating the functionality of skin cells derived from induced pluripotent stem cells and replicating various skin phenotypes. • The entire process, from thawing skin cells to establishing the graft, requires 54 days. Graphical overview.

Deconstructing cellular senescence in bone and beyond.

Osteocytes are specialized bone cells that orchestrate skeletal remodeling. Senescent osteocytes are characterized by an activation of cyclin-dependent kinase inhibitor p16Ink4a and have been implicated in the pathogenesis of several bone loss disorders. In this issue of the JCI, Farr et al. have now shown that systemic removal of senescent cells (termed senolysis) prevented age-related bone loss at the spine and femur and mitigated bone marrow adiposity through a robust effect on osteoblasts and osteoclasts, whereas cell-specific senolysis in osteocytes alone was only partially effective. Surprisingly, transplantation of senescent fibroblasts into the peritoneum of young mice caused host osteocyte senescence associated with bone loss. This refined concept of osteocyte senescence and the effects of remote senolysis may help to develop improved senolytic strategies against multisystem aging in bone and beyond.

Comparing COL7A1 gene expression in fibroblast cells of dystrophic epidermolysis bullosa patients with clinical responses to autologous fibroblasts transplantation

Objectives: This clinical research aimed to establish autologous fibroblasts transplantation as a possible treatment for patients with DEJ. The COL7A1 gene expression was also evaluated.
 Methods: Six patients (3M and 3F), 4 with no recurrent wounds and 2 with recurrent wounds after surgery, and 15 healthy subjects were included in the study as controls. Quantitative real-time polymerase chain reaction (real-time PCR) analysis of the COL7A1 gene was performed using an oligonucleotide primer pair designed to amplify across the exon/exon junction.
 Results: The COL7A1 expression level was down-regulated at exons 26-27, 47-48, 96-97, and 116-117 in all patients′ fibroblasts compared with the healthy controls. However, the expression of the COL7A1 gene in the fibroblasts of the patients with a positive response to the treatment was not significantly changed compared with the patients with the poor response. (ClinicalTrials.gov NCT01908088)
 Conclusion: In this study the mRNA expression levels of COL7A1 were significantly less in the patients when compared with healthy controls. However the COL7A1 expression after autologous fibroblasts transplantation was not different between the two groups of patients, and further examination is needed to elucidate the mechanism of the treatment.

Fetal Fibroblast Transplantation via Ablative Fractional Laser Irradiation Reduces Scarring

Scar treatments include fractional laser treatment, cell transplantation, surgery, skin needling, and dermal fillers. Fractional laser treatments are used to reduce scarring and blurring. Cell transplantation is promising, with mature fibroblasts and adipose-derived stem cells being used clinically, while embryonic fibroblasts are used experimentally. Herein, we developed a combination of ablative CO2 (carbon dioxide) fractional laser and cell transplantation for the treatment of scars. Eight-week-old male C57Bl/6 mice were used to create a full-layer skin defect in the back skin and create scars. The scar was then irradiated using a CO2 fractional laser. The cells were then transplanted onto the scar surface and sealed with a film agent. The transplanted cells were GFP-positive murine fetal fibroblasts (FB), fetal fibroblasts with a long-term sphere-forming culture (LS), and fetal skin with a short-term sphere-forming culture (SS). After transplantation, green fluorescent protein (GFP)-positive cells were scattered in the dermal papillary layer and subcutis in all the groups. LS significantly reduced the degree of scarring, which was closest to normal skin. In conclusion, the combination of ablative fractional laser irradiation and fetal fibroblast transplantation allowed us to develop new methods for scar treatment.

Comprehensive approach to correct involutional-dystrophic skin changes in women

Skin aging is one of the most urgent problems that is not being studied today. The study involved 107 women with signs of age-related changes in the skin of the face aged 25 to 60 years. They were treated according to our autor’s technology neofibrolifting - autologous fibroblasts transplantation into the pretreated with platelet-rich plasma skin and ablative fractional photothermolysis procedure. The developed neofibrolifting technology allows reconstructing authentic skin structure, improving its appearance and immunity.

Allotransplantation of ascorbic acid-treated fibroblasts improves healing of excisional cutaneous wound in diabetic rats

The purpose of this study was to evaluate the effects of ascorbic acid (AA)-treated fibroblasts transplantation on excisional diabetic wound healing. An excisional wound was created between the shoulders of streptozotocin-induced diabetic rats. On day three, 1 ml of PBS, ‎1 × 106 ‎intact homologous fibroblasts, and ‎1 × 106 ‎ fibroblasts treated with 50 μM AA were injected subcutaneously around the wound edges in control, treatment-1 and treatment-2 groups, respectively. In the sham group, the wound was left intact. Wound area was measured by planimetry. On day 15, samples were harvested for histopathological examination and hydroxyproline content. Wound area in treatment-1 and − 2 groups was ‎significantly decreased compared to other groups, on days 11 and 15. The hydroxyproline content was significantly lower in the control group compared to the other groups. Histopathology revealed significant increases in the number of neovessels, macrophages, lymphocytes and fibroblasts in the treatment-2 group compared to the other groups. Trichrome staining showed the highest level of collagen deposition and orientation in the treatment-2 group. In conclusion, allotransplantation of ‎50 μM ‎ AA-treated fibroblasts ‎could result in progressive healing and improved reparative indices of excisional dermal wound in diabetic rats.

The effect of mesenchymal stromal cells of various origins on mortality and neurologic deficit in acute ischemia-reperfusion in rats

Stroke is a global epidemic issue and the second leading cause of death in the world and in Ukraine. According to official statistics, every year 100-110 thousand Ukrainians suffer acute cerebrovascular disorders. One third of such patients are of working age, up to 50 % will have a disability, and only one in ten will fully return to full life. So far, promising experimental data on the treatment of neurological dysfunction using mesenchymal stromal cells (MSCs) have been obtained. The aim of study is to compare the effect of MSCs of different origins on mortality and neurologic deficit in rats with acute cerebral ischemia-reperfusion injury (CIRI). Materials and methods. Transient bilateral 20-minute occlusion of internal carotid arteries was modeled in male Wistar rats aged 4 months and animals were injected intravenously with MSCs derived from human umbilical cord Wharton's-jelly (hWJ-MSC), human and rat adipose tissue. Other groups of experimental animals were injected intravenously with rat fetal fibroblasts and cell lysate from hWJ-MSC. The last group of rats received Citicoline at a dose of 250 mg/kg as a reference drug. Control animals were injected intravenously with normal saline. The cerebroprotective effect of therapy was assessed by mortality and neurologic deficit in rats on the McGraw's stroke index score. Results. After 12 hours of observation in the crucial period in the development of experimental acute cerebrovascular disorders with the administration of hWJ-MSC, mortality was only 10 % against 45 % of animals in the control group. The use of rat fetal fibroblasts reduced the mortality of animals compare to the control group by an average of 25 %. CIRI in rats caused severe neurologic deficits: paralysis, paresis, ptosis, circling behavior. On the 7th day of observation in the control group of animals, the mean score on the McGrow's stroke index indicated severe neurological disorders. On the 14th day of observation in this group of animals there was no complete recovery of lost central nervous system functions. Compared with the control group of animals, all the treatment agents for acute CIRI (MSCs of various origins, MSC's lysate and Citicoline) contributed to a significant regression of neurologic deficit. Conclusions. Thus, transplantation of human Wharton's jelly-derived MSCs and rat fetal fibroblasts reduced mortality and alleviated neurological symptoms in rats with experimental ischemic stroke. hWJ-MSC, rat fetal fibroblasts, and rat adipose-derived MSCs reduced the incidence of neurological disorders better than Citicoline, which was accompanied by a regression of neurologic deficit dynamics on the 14th day of follow-up. The ability of stem cells of different origins to reduce neurologic deficit indicates the feasibility of their use in experimental acute cerebral ischemia.

Can plantar fibroblast implantation protect amputees from skin injury? A recipe for skin augmentation.

Skin injuries remain a persistent problem for users of lower-limb prostheses despite sustained progress in prosthesis design. One factor limiting the prevention of skin injuries is that skin on the residual limb is not suited to bear the mechanical loads of ambulation. One part of the body that is suited to this task is the sole of the foot. Here, we propose a novel strategy to actively augment skin's tolerance to load, increasing its resistance to mechanically induced injuries. We hypothesise that the load tolerance of skin can be augmented by autologous transplantation of plantar fibroblasts into the residual limb dermis. We expect that introducing plantar fibroblasts will induce the overlying keratinocytes to express plantar-specific keratins leading to a tougher epidermis. Using a computational finite element model of a weight-bearing residual limb, we estimate that skin deformation (a key driver of pressure ulcer injuries) could be halved by reprogramming skin to a plantar-like phenotype. We believe this strategy could yield new progress in pressure ulcer prevention for amputees, facilitating rehabilitation and improving quality of life for patients.

Senescent Cell-Secreted Netrin-1 Modulates Aging-Related Disorders by Recruiting Sympathetic Fibers.

Cellular senescence is implicated in several lines of aging-related disorders. However, the potential molecular mechanisms by which cellular senescence modulates age-related pathologies remain largely unexplored. Herein, we report that the density of sympathetic fibers (SFs) is significantly elevated in naturally aged mouse tissues and human colon adenoma tissues compared to the SFs densities in the corresponding young mouse tissues and human non-lesion colon tissues. A dorsal root ganglion (DRG)-human diploid fibroblast coculture assay revealed that senescent cells promote the outgrowth of SFs, indicating that the senescent cells induce recruitment of SFs in vitro. Additionally, subcutaneous transplantation of 2BS fibroblasts in nude mice shows that transplanted senescent 2BS fibroblasts promote SFs infiltration. Intra-articular senolytic molecular injection can reduce SFs density and inhibit SFs infiltration caused by senescent cells in osteoarthritis (OA), suggesting senescent cells promote the infiltration of SFs in vivo in aged tissues. Notably, the elevated level of SFs contributes to impaired cognitive function in naturally aged mice, which can be reversed by treatment with propranolol hydrochloride, a non-selective β receptor blocker that inhibits sympathetic nerve activity (SNA) by blocking non-selective β receptors. Additionally, 6-hydroxydopamine (6-OHDA)-induced sympathectomy improved hepatic sympathetic overactivity mediated hepatic steatosis in high fat diet (HFD)-fed APOE knockout mice (APOE−/− mice) by reducing hepatic SNA. Taken together, this study concludes that senescent cell-secreted netrin-1 mediated SFs outgrowth and infiltration, which contributes to aging-related disorders, suggesting that clearing senescent cells or inhibiting SNA is a promising therapeutic strategy for improving sympathetic nervous system (SNS) hyperactivity-induced aging-related pathologies.

Transplantation of autologous cells and porous gelatin microcarriers to promote wound healing

Definitive treatment to achieve wound healing in major burns frequently include skin transplantation, where split-thickness skin grafts is considered gold standard. This method is associated with several drawbacks. To overcome these hurdles, efforts have been made to develop tissue engineered skin substitutes, often comprised of a combination of cells and biomaterials. In the present study, we aimed to investigate transplantation of autologous keratinocytes and fibroblasts seeded on porous gelatin microcarriers using a porcine wound model. Pre-seeded microcarriers were transplanted to a total of 168 surgical full-thickness wounds (2cm diameter) on eight adult female pigs and covered with occlusive dressings. The experimental groups included wounds transplanted with microcarriers seeded with the combination of keratinocytes and fibroblasts, microcarriers seeded with each cell type individually, microcarriers without cells, each cell type in suspension, and NaCl control. Wounds were allowed to heal for one, two, four or eight weeks before being excised and fixated for subsequent histological and immunohistochemical analysis. In vitro, we confirmed that viable cells populate the surface and the pores of the microcarriers. In vivo, the microcarriers were to a large extent degraded after two weeks. After one week, all treatment groups, with the exception of microcarriers alone, displayed significantly thicker neo-epidermis compared to controls. After two weeks, wounds transplanted with microcarriers seeded with cells displayed significantly thicker neo-epidermis compared to controls. After four weeks there was no difference in the thickness of neo-epidermis. In conclusion, the experiments performed illustrate that autologous cells seeded on porous gelatin microcarriers stimulates the re-epithelialization of wounds. This method could be a promising candidate for skin transplantation. Future studies will focus on additional outcome parameters to evaluate long-term quality of healing following transplantation.

Umbilical cord-matrix stem cells induce the functional restoration of vascular endothelial cells and enhance skin wound healing in diabetic mice via the polarized macrophages

BackgroundChronic nonhealing wounds represent one of the most common complications of diabetes and require advanced treatment strategies. Increasing evidence supports the important role of mesenchymal stem cells in diabetic wound healing; however, the underlying mechanism remains unclear. Here, we explored the effects of umbilical cord-matrix stem cells (UCMSCs) on diabetic wound healing and the underlying mechanism.MethodsUCMSCs or conditioned medium (UCMSC-CM) were injected into the cutaneous wounds of streptozotocin-induced diabetic mice. The effects of this treatment on macrophages and diabetic vascular endothelial cells were investigated in vivo and in vitro.ResultsOur results reveal that UCMSCs or UCMSC-CM accelerated wound healing by enhancing angiogenesis. The number of host macrophages recruited to the wound tissue by local infusion of UCMSCs was greater than that recruited by fibroblast transplantation or control. The frequency of M2 macrophages was increased by UCMSC transplantation or UCMSC-CM injection, which promoted the expression of cytokines derived from M2 macrophages. Furthermore, when cocultured with UCMSCs or UCMSC-CM, lipopolysaccharide-induced macrophages acquired an anti-inflammatory M2 phenotype characterized by the increased secretion of the cytokines interleukin (IL)-10 and vascular endothelial growth factor and the suppressed production of tumor necrosis factor-α and IL-6. UCMSC-CM-activated macrophages significantly enhanced diabetic vascular endothelial cell functions, including angiogenesis, migration, and chemotaxis. Moreover, the action of UCMSC-CM on macrophages or vascular endothelial cells was abrogated by the administration of neutralizing antibodies against prostaglandin E2 (PGE2) or by the inhibition of PGE2 secretion from UCMSCs.ConclusionsOur findings demonstrate that UCMSCs can induce the functional restoration of vascular endothelial cells via the remodeling of macrophage phenotypes, which might contribute to the marked acceleration of wound healing in diabetic mice.Graphical

An Open-Label Study of Low-Level Laser Therapy Followed by Autologous Fibroblast Transplantation for Healing Grade 3 Burn Wounds in Diabetic Patients.

Introduction: Low-level laser therapy (LLLT) has been used as an effective therapeutic modality since the mid-1960s. Although there have been several clinical studies using LLLT in wound healing, especially diabetic, pressure and venous ulcers, there are few reports of using this technique in burn ulcers. Autologous fibroblast transplantation is a novel treatment for patients with burns or venous ulcers. In this study for the first time, we used LLLT along with autologous fibroblast skin transplantation to treat grade 3 burn ulcers in diabetic patients. This case series describes the successful management of grade 3 burn ulcers in 10 diabetic patients using autologous fibroblast transplantation along with LLLT. Methods: After the approval of the Tehran University Ethics Committee (IR.TUMS.REC.1394.1683) and the Iran Registry of Clinical Trials (IRCT2016050226069N3), 10 diabetic patients with 10 grade 3 burn ulcers, who were a candidate for skin graft surgery, entered the study. Donor skin was biopsied using a 3 mm punch. Fibroblasts were extracted and cultured in vitro in the GMP Technique laboratory. The patients were treated using LLLT in 3-4 weeks during the time that fibroblast cultures became ready to use. Laser irradiation was done using red light, 650 nm, 150 mW, 1 J/cm2 for the bed of the ulcer and infra-red light 808 nm, 200 mW, 6 J/cm2 for the margins every other day for 10 sessions. Results: The mean wound size before treatment was 16.28 cm2 . All patients' burn wounds healed completely after 10-12 weeks. Conclusion: We conclude that this method can be used as an effective method for treating large wounds, especially in complicated patients including the diabetics.

Prevention of the Formation of Unaesthetic Scars Following the Surgical Cutaneous Wounds Healing of the Jaw and Facial Region Based on Transplantation of Xenogenic Fibroblasts

Prevention of the Formation of Unaesthetic Scars Following the Surgical Cutaneous Wounds Healing of the Jaw and Facial Region Based on Transplantation of Xenogenic Fibroblasts

Long-Term Follow-up of Autologous Fibroblast Transplantation for Facial Contour Deformities, A Non-Randomized Phase IIa Clinical Trial.

Objective Recently, the promising potential of fibroblast transplantation has become a novel modality for skin rejuvenation. We investigated the long-term safety and efficacy of autologous fibroblast transplantation for participants with mild to severe facial contour deformities. Materials and Methods In this open-label, single-arm phase IIa clinical trial, a total of 57 participants with wrinkles (n=37, 132 treatment sites) or acne scars (n=20, 36 treatment sites) who had an evaluator’s assessment score of at least 2 out 7 (based on a standard photo-guide scoring) received 3 injections of autologous cultured fibroblasts administered at 4-6 week intervals. Efficacy evaluations were performed at 2, 6, 12, and 24 months after the final injection based on evaluator and patient’s assessment scores. Results Our study showed a mean improvement of 2 scores in the wrinkle and acne scar treatment sites. At sixth months after transplantation, 90.1% of the wrinkle sites and 86.1% of the acne scar sites showed at least a one grade improvement on evaluator assessments. We also observed at least a 2-grade improvement in 56.1% of the wrinkle sites and 63.9% of the acne scar sites. A total of 70.5% of wrinkle sites and 72.2% of acne scar sites were scored as good or excellent on patient assessments. The efficacy outcomes remained stable up to 24-month. We did not observe any serious adverse events during the study. ConclusionThese results have shown that autologous fibroblast transplantation could be a promising remodeling modality with long-term corrective ability and minimal adverse events (Registration Number: NCT01115634).

Intracerebral transplantation of erythropoietin-producing fibroblasts facilitates neurogenesis and functional recovery in an ischemic stroke model.

IntroductionErythropoietin (EPO) can enhance neurogenesis and fibroblasts can secrete growth factors; together, they may benefit ischemic stroke. We transplanted EPO‐producing fibroblasts into the rodent infarcted brain to test their effect on neurogenesis and functional recovery.MethodsA total of 106 cells of EPO‐producing NIH/3T3 fibroblasts (EPO/EGFP/3T3) or enhanced green fluorescence protein (EGFP)‐expressing fibroblasts (EGFP/3T3) were stereotaxically injected into the infarcted striatum of adult rats that received transient middle cerebral artery occlusion (MCAO) surgery 1 day poststroke. On day 14 after MCAO, the animals were euthanized for the evaluation of neurogenesis via immunohistochemistry and of the expression of growth factors using enzyme‐linked immunosorbent assay. The infarct volume was analyzed using magnetic resonance imaging and the neurological behavior was assessed using the neurological severity scoring performed within 14 days after MCAO.ResultsThe MCAO rats with EPO/EGFP/3T3 treatment showed high EPO expression in the infarcted brain for at least 1 week. The concentration of brain‐derived neurotrophic factor was higher in both hemispheres of MCAO rats with either EGFP/3T3 or EPO/EGFP/3T3 treatment at 14 days poststroke compared with untreated MCAO rats. The number of Ki‐67‐, nestin‐, or doublecortin‐immunoreactive cells in bilateral subventricular zones was higher in EPO/EGFP/3T3‐treated MCAO rats than it was in untreated MCAO control animals, indicating the enhancement of neurogenesis after EPO/EGFP/3T3 treatment. Notably, post‐MCAO EPO/EGFP/3T3 treatment significantly reduced infarct size and improved functional recovery.ConclusionThe intracerebral transplantation of EPO‐producing fibroblasts benefited an ischemic stroke model probably via the enhancement of neurogenesis.

Effects of combined transplantation of rat Schwann cells and fibroblasts on nerve regeneration of denervated perforator flaps in rats and the mechanism

Effects of combined transplantation of rat Schwann cells and fibroblasts on nerve regeneration of denervated perforator flaps in rats and the mechanism

Experience in the clinical use of allogeneic fibroblasts in patients with severe burns

Purpose. To evaluate the results of the application of allogenic fibroblasts in patients with extensive thermal burns.
 Methods. The study included 34 patients with burns over 20% TBSA, treated in the burn ICU. In accordance with the indications for transplantation of fibroblasts, all patients were divided into 4 groups: stimulation of regeneration of superficial burns (n = 10), stimulation of regeneration after meshed skin graft (n = 14), reduction of healing time for donor wounds (n = 6) and acceleration growth of granulations after the escharectomy (n = 4).
 Results. A positive effect of fibroblast transplantation was found in 7 (70%) patients of the first group, 13 (93%) of the patients in the second group, 2 (33%) of the third group and 2 (50%) in the fourth study group.
 Conclusion. The maximum positive effect of transplantation of human dermal fibroblasts can be observed when performing the meshed skin graft and treating the superficial burns.

Therapeutic effects of cell therapy with neonatal human dermal fibroblasts and rabbit dermal fibroblasts on disc degeneration and inflammation

BACKGROUND CONTEXTIncreasing evidence suggests transplanting viable cells into the degenerating intervertebral disc (IVD) may be effective in treating disc degeneration and back pain. Clinical studies utilizing autologous or allogeneic mesenchymal stem cells to treat patients with back pain have reported some encouraging results. Animal studies have shown that cells injected into the disc can survive for months and have regenerative effects. Studies to determine the advantages and disadvantages of cell types and sources for therapy are needed. PURPOSEThe objective of this study is to determine the impact of donor source on the therapeutic effects of dermal fibroblast treatment on disc degeneration and inflammation. STUDY DESIGNUsing the rabbit disc degeneration model, we compared transplantation of neonatal human dermal fibroblasts (nHDFs) and rabbit dermal fibroblasts (RDFs) into rabbit degenerated discs on host immune response, disc height, and IVD composition. METHODSNew Zealand white rabbits received an annular puncture using an 18-guage needle to induce disc degeneration. Four weeks after injury, rabbit IVDs were treated with 5 × 106 nHDFs, RDFs, or saline. At eight weeks post-treatment, animals were sacrificed. X-ray images were obtained. IVDs were isolated for inflammatory and collagen gene expression analysis using real-time polymerase chain reaction and biochemical analysis of proteoglycan contents using dimethylmethylene blue assay. These studies were funded by a research grant from SpinalCyte, LLC ($414,431). RESULTSEight weeks after treatment, disc height indexes of discs treated with nHDF increased significantly by 7.8% (p<.01), whereas those treated with saline or RDF increased by 1.5% and 2.0%, respectively. Gene expression analysis showed that discs transplanted with nHDFs and RDFs displayed similar inflammatory responses (p=.2 to .8). Compared to intact discs, expression of both collagen types I and II increased significantly in nHDF-treated discs (p<.05), trending to significant in RDF-treated discs, and not significantly in saline treated discs. The ratio of collagen type II/collagen type I was higher in the IVDs treated with nHDFs (1.26) than those treated with RDFs (0.81) or saline (0.59) and intact discs (1.00). Last, proteoglycan contents increased significantly in discs treated with nHDF (p<.05) and were trending toward significance in the RDF-treated discs compared to those treated with saline. CONCLUSIONSThis study showed that cell transplantation with nHDF into degenerated IVDs can significantly increase markers of disc regeneration (disc height, collagen type I and II gene expression, and proteoglycan contents). Transplantation with RDFs showed similar regenerative trends, but these trends were not significant. This study also showed that the human cells transplanted into the rabbit discs did not induce a higher immune response than the rabbit cells. These results support that the IVD is immune privileged and would tolerate allogeneic or xenogeneic grafts.

Immunological Properties of Human Embryonic Stem Cell-Derived Retinal Pigment Epithelial Cells.

SummaryAge-related macular degeneration is caused by dysfunction and loss of retinal pigment epithelium (RPE) cells, and their transplantation may rescue visual functions and delay disease progression. Human embryonic stem cells (hESCs) may be an unlimited source of RPE cells for allotransplantation. We analyzed the immunomodulatory properties of hESC-derived RPE (hESC-RPE) cells, and showed that they inhibited T cell responses. Co-culture experiments showed that RPE cells inhibited interfon-γ secretion and proliferation of activated T cells. Furthermore, hESC-RPE cells enhanced T cell apoptosis and secretion of the anti-inflammatory cytokine interleukin-10 (IL-10). In addition, RPE cells altered the expression of T cell activation markers, CD69 and CD25. RPE cells transplanted into RCS rats without immunosuppression survived, provided retinal rescue, and enhanced IL-10 blood levels. Our data suggest that hESC-RPE cells have immunosuppressive properties. Further studies will determine if these properties are sufficient to alleviate the need for immunosuppression therapy after their clinical allotransplantation.