Amniotic membrane mesenchymal stromal cell-derived secretome in the treatment of acute ischemic stroke:A case report

BACKGROUND Stroke is the second and third leading cause of death and disability,respectively.To date,no definitive treatment can repair lost brain function.Recently,various preclinical studies have been reported on mesenchymal stromal cells(MSCs)and their derivatives and their potential as alternative therapies for stroke.CASE SUMMARY A 45-year-old female suffered an acute stroke,which led to paralysis in the left upper and lower limbs.The amniotic membrane MSC-derived secretome(MSCsecretome)was intravenously transplanted once a week for 4 wk.MSC-secretomeregulated regulatory T cells were investigated for the beneficial effects.The clinical improvement of this patient was accompanied by an increased frequency of regulatory T cells after transplantation.CONCLUSION Intravenous administration of MSC-secretome can potentially treat patients who suffer from acute ischemic stroke.

Amniotic membrane transplantation: an updated clinical review for the ophthalmologist

Although amniotic membrane transplantation(AMT)has long been used as an essential surgical technique for ocular surface reconstruction,its role continues to evolve and expand.In the management of numerous ocular surface disorders,ranging from inflammatory to infectious,traumatic to neoplastic,the ability to perform AMT is a valuable addition to the skillset of any ophthalmologist.The purpose of this paper is to provide ophthalmologists with an updated,evidence-based review of the clinical indications for AMT in corneal and conjunctival reconstruction,reviewing its common and even experimental applications known to date.The methods of amniotic membrane preservation,the available commercial amniotic membrane products to date,and future directions for amniotic membrane use,including amniotic membrane extract eye drops(AMEED),are also discussed.It is paramount for ophthalmologists to stay up-to-date on the applications of AMT so as to effectively incorporate this versatile treatment modality into their practice,both in the operating room and in the clinic.By familiarizing the general ophthalmologist with its diverse applications,we hope to motivate general ophthalmologists to incorporate the use of AMT into their clinical practice,or provide guidance on how to recognize when referral to a corneal specialist for amniotic membrane application is prudent.

Efficacy of rhNGF-loaded amniotic membrane transplantation for rabbit corneal epithelial and nerve regeneration

AIM:To evaluate the efficacy of recombinant human nerve growth factor-loaded amniotic membrane(rh NGF-AM)on corneal epithelial and nerve regeneration in rabbit model.METHODS:Freshly prepared human amniotic membrane(AM)were immersed into PBS buffer containing 100 or 500μg/mL rh NGF for 15,30,and 60 min at 4℃.The in vitro release kinetics of rh NGF was measured with ELISA.For in vivo evaluation,the AM were immersed with 500μg/mL rh NGF for 30 min.Fifty-seven rabbits were selected to establish corneal epithelial defect model.In addition to the 19 rabbits in control group,38 rabbits received AM transplantation with or without rh NGF after the removal of central epithelium.Corneal epithelial defect area,sub-epithelial nerve fiber density,corneal sensitivity,rh NGF contents in resident AM and corneas were measured after the surgery.RESULTS:rh NGF was sustained release from the AM within 14 d in vitro,with the positive correlation with initial immersion concentration.The immersion of AM in 500μg/mL rh NGF for 30 min achieved the most stable release within 14 d.After transplantation in rabbit cornea,a high concentration of rh NGF in resident rh NGF-AM and cornea was maintained within 8 d.Corneal epithelial healing,nerve fiber regeneration and the recovery of corneal sensitivity were significantly accelerated after the rh NGF-AM transplantation when compared to simple AM transplantation(all P<0.05).CONCLUSION:Simple immersion of AM achieves the sustained release of rh NGF,and promotes corneal epithelial wound healing and nerve regeneration,as well as the recovery of corneal sensitivity in rabbit.

Amniotic membrane welded to contact lens by 1470-nm diode laser:a novel method for sutureless amniotic membrane transplantation

AIM: To avoid the side effects of the suture usage by welding amniotic membrane(AM) to contact lens(CL)with laser.METHODS: AM was taken from pregnant women and cleaned from blood clots with sterile phosphate-buffered physiological saline solution which included antibiotics.Stromal side of the AM was spread inside of the CL and it was welded to CL by 1470 nm diode laser. And 600 μm diameter fiber tip of the laser was contacted with the epithelial side of the AM from 4 separate points. After welding excess amniotic membrane around the CL was cut with a scalpel.RESULTS: Stromal side of the AM was spread inside of the CL and then with laser fiber, different power levels and exposure times were applied on the epithelium of AM and 340 m W for seven seconds was found optimal.CL and AM attached with the spot welding effect in 4points by touching fiber tip. CL-AM welded complex did not separated from each other while holding AM that extend beyond the CL with the help of two forceps.CONCLUSION: As a conclusion, it was aimed in this study to achieve the success of the conventional amniotic membrane transplantation(AMT) with the easiness of applying a CL and to avoid risks and side effects of corneal or conjunctival suturing. The results showed that the application of the CL-AM complex will be as easy as the application of a CL and lasts shortly.

Amniotic membrane for covering high myopic macular hole associated with retinal detachment following failed primary surgery

AIM:To evaluate the therapeutic effect of amniotic membrane(AM)for covering high myopic macular hole associated with retinal detachment following failed primary surgery.METHODS:Seventeen eyes of 17 patients whose axial length was more than 29 mm suffered from macular hole(MH)or MH associated with retinal detachment(RD),and had previously surgery of pars plana vitrectomy(PPV)with internal limiting membrane(ILM)peeling and silicone oil(SO)tamponade.Half a year after the surgery,optical coherence tomography(OCT)showed that MH did not heal in all 17 eyes and RD was still maintained in 13 eyes of these 17 eyes.We performed SO removal combined with AM covering on macular area and C3 F8 tamponade,and phacoemulsification combined with intraocular lens implantation simultaneously cataract eyes.We followed up these patients for one year.RESULTS:In all 17 eyes,SO was removed successfully,MHs were healed and RDs were reattached.One eye(5.89%,1/17)had AM shifted half a month after surgery and underwent a second surgery to adjust the position of the AM and supplement C3 F8.After surgery,the visual acuity(VA)improved in 15 eyes(88.24%,15/17),no change in two eyes(11.76%,2/17).No serious complications occurred in all eyes.CONCLUSION:AM covering is helpful to rescue the previous failure surgery of high myopic MH.

Amniotic membrane as a potent source of stem cells and a matrix for engineering heart tissue

Existing therapies for the treatment of chronic heart failure still have some limitations and there is a pressing need for the development of new therapeutic modalities. The amniotic membrane has been used for the treatment of various diseases, such as conjunctive defects;however, the mechanisms behind its repair functions are still unclear. Regenerative medicine is seeking newer alternatives and among them, biomaterials have emerged in recent years for developing and manipulating molecules, cells, tissues or organs grown in laboratories in order to replace human body parts. Many such materials have been used for this purpose, either synthetically or biologically, in order to provide new medical devices. This review provides a wider view of the regeneration potential of the use of amniotic membrane as a potential biomaterial to facilitate the implementation of new research in surgical procedures. Amniotic membrane appears to be an alternative source of stem cells as well as an excellent biomaterial for cell-based therapeutic applications in engineering heart tissue.

Amniotic membrane transplantation in a patient with impending perforated corneal ulcer caused by Streptococcus mitis: A case report and review of literature

BACKGROUND Streptococcus mitis(S.mitis)is an opportunistic pathogen that can lead to severe ocular infections.In previous reports,penetrating keratoplasty(PK)was usually adopted for the treatment of persistent corneal ulcers.This report describes an unusual case of nonhealing descemetocele caused by S.mitis treated by antibiotics plus amniotic membrane transplantation(AMT).CASE SUMMARY A 63-year-old woman presented with a right persistent corneal ulcer that she had suffered from for the past 9 mo.The culture of a corneal scraping yielded S.mitis.The right eye descemetocele decreased in diameter from 3 to 0.8 mm after the continuous administration of topical vancomycin and ceftriaxone for 2 wk.Due to the slow healing,AMT was performed.Her corneal erosion healed and gradually became clear.Her visual acuity recovered from initially counting fingers to 100/200 at the last follow-up,67 mo after AMT.CONCLUSION Antibiotics plus AMT may be an effective alternative treatment other than PK to promote epithelializationand to reduce inflammation in the corneas complicated by S. mitis keratitis.

Significant impact of cryopreserved amniotic membrane on acute ocular Stevens-Johnson syndrome and toxic epidermal necrolysis

The ocular surface is covered by an epithelium encompassing an area including the cornea,the limbus and the conjunctiva bordered by the upper and lower lids.The healthy state of the ocular surface epithelium depends on a stable and protective preocular tear film when the eye is open.A stable preocular tear film is governed by sound ocular surface defense that involves effective

Group B Streptococcal Chorioamnionitis with Intact Amniotic Membranes. A Rare?

Group B streptococcus infection (GBS) is an important cause of perinatal infection. Maternal colonization by GBS can cause amniotic infection and thus fetal infection, sometimes causing fetal death. This infection generally occurs in association with premature rupture of membranes. We present here an infrequent case of GBS chorioamnionitis in full-term gestation with intact amniotic membranes. The curiosity of the case lies in the integrity of the amniotic membranes, the asymptomatic clinical presentation, and the adverse result (term fetal death).

Cytoprotective effect of amniotic membrane extracts on human corneal epithelial cells exposed to benzalkonium chloride in vitro

Background:The goal was to explore the protective effect and potential mechanism of amniotic membrane extracts(AME)on the ocular surface exposed to benzalkonium chloride(BAC).Methods:The human corneal epithelial cell(HCEC)line SD-HCEC1s was cultured in 5 groups:normal control(NC),NC+AME,BAC,BAC+NC,and BAC+AME.Cell viability analysis,flow cytometry analysis,real-time polymerase chain reaction(PCR),and western blot were employed to measure changes in cell function.Matrix metalloproteinases(MMPs)and inflammatory cytokines were assayed by enzyme-linked immunosorbent assay(ELISA)and activity assays.Results:Real-time PCR and western blot analysis demonstrated that the expressional level of caspase-8 was increased while the levels of Muc1,Muc4,and Muc16 were decreased after treatment with 0.02%BAC for 1 h.When the SD-HCEC1s were withdrawn from the BAC and switched to media containing 10%AME for 2 days,the expression level of capsase-8 was decreased while the levels of Muc1,Muc4,and Muc16 were increased.Real-time PCR and ELISA demonstrated that the mRNA and protein levels of MMP-1,MMP-3,MMP-13,CXCL1,interleukin(IL)-1β,IL-6,and tumor necrosis factor-alpha(TNF-α)were significantly increased after treatment with 0.02%BAC,whereas those of MMP-8 were decreased.When the 0.02%BAC was withdrawn and the SD-HCEC1s were cultured in 10%AME,the mRNA and protein levels of MMP-1,MMP-3,MMP-13,CXCL1,IL-1β,IL-6,and TNF-αwere decreased,while those of MMP-8 were increased.MMP-8 activity assays confirmed that IL-1βand TNF-αdownregulated the protein levels of MMP-8.Conclusions:AME protects SD-HCEC1s when stressed in BAC via upregulation of MMP-8 and downregulation of IL-1βand TNF-α.AME may have the potential functions to be employed as a topical adjunctive therapy in eyes chronically exposed to BAC.

Human Amniotic Membrane Promotes Antimicrobial Microenvironment in a Device-Related Infection

Hospital inquired post-operative infections are a leading cause of morbidity and mortality in patients receiving left ventricular assist devices. We present the case of a patient who acquired Candida albicans and Staphylococci infections following left ventricular assist device implantation. Use of standard antibiotics caused the infection to worsen, thus an amniotic membrane patch was used as a last-resort treatment. Within 6 weeks of the amniotic membrane patch treatment, the infection resolved, the wound appeared exceptionally clean upon inspection, and granulation tissue was present. After the infection resolved, a successful latissimusdorsi tissue flap procedure was completed and the patient made a full recovery.

Amniotic Membrane Grafts in Pediatric Corneal Limbal Dermoids with Conjunctival Eyelashes: A Case Presentation

Purpose: To report a case of a pediatric corneal limbal dermoid with eyelashes and to describe post-operative changes after excision with reconstruction using amniotic membrane grafting, sutures and fibrinogen-thrombin glue. Case Report: One pediatric patient was identified with a grade II infratemporal corneal-limbal dermoid with conjunctival eyelashes. The dermoid was surgically excised and the cornea reconstructed with amniotic membrane using sutures and fibrinogen/thrombin glue. Preoperative and postoperative measurement of astigmatism, anisometropia and presence of exposure keratopathy were performed.

Amniotic membrane as a novel treatment in age-related macular degeneration: a narrative review

Age-related macular degeneration(ARMD),one of the most common causes of blindness,should be considered more due to its exponential increase in the coming 20 years as a result of increasing the age of the population.Whereas more recent studies offered newer scaling systems for ARMD,traditionally it is classified as the early and late stages.The main injury in this disease occurred in retinal pigment epithelium(RPE)and the retina.RPE cells have a crucial role in hemostasis and supporting photoreceptors.In the early stages,damages to RPE are minimal and mainly no treatment is needed because most patients are asymptomatic.However,in the late stages,RPE impairment may lead to the invasion of choroidal vessels into the retina.Although anti-angiogenic agents can inhibit this abnormal growth of blood vessels,they cannot stop it completely,and finally,total loss of retinal cells may occur(geographical atrophy).Since this prevalent disease has not had any cure yet,the concept of substituting the RPE cells should be considered.Repairing the injury to central nervous system cells is almost impossible because the regenerative capacity of these cells is limited.Recently,the use of regenerative substitutes has been suggested to replace damaged tissues.Amniotic membrane(AM)has been raised as a suitable substitute for damaged RPE cells due to all of its unique properties:pluripotency,anti-angiogenic effect,and anti-inflammatory effect.Based on the few studies that have been published so far,it seems that the use of this membrane in the treatment of ARMD can be helpful,but more studies are needed.

Hyperdry human amniotic membrane application as a wound dressing for a full-thickness skin excision after a third-degree burn injury

Background:Severe burn injuries create large skin defects that render the host susceptible to bacterial infections.Burn wound infection often causes systemic sepsis and severe septicemia,resulting in an increase in the mortality of patients with severe burn injuries.Therefore,appropriate wound care is important to prevent infection and improve patient outcomes.However,it is difficult to heal a third-degree burn injury.The aim of this studywas to investigate whether hyperdry human amniotic membrane(HD-AM)could promote early granulation tissue formation after full-thickness skin excision in third-degree burn injury sites in mice.Methods:After the development of HD-AM and creation of a third-degree burn injury model,the HD-AM was either placed or not placed on the wound area in the HD-AM group or HD-AM group,respectively.The groups were prepared for evaluation on postoperative days 1,4 and 7.Azan staining was used for granulation tissue evaluation,and estimation of CD163,transforming growth factor beta-1(TGF-β1),vascular endothelial growth factor(VEGF),CD31,alpha-smooth muscle actin(α-SMA)and Iba1 expression was performed by immunohistochemical staining.Quantitative reverse-transcription polymerase chain reaction(PCR)was used to investigate gene expression of growth factors,cell migration chemokines and angiogenic and inflammatory markers.Results:The HD-AM group showed significant early and qualitatively good growth of granulation tissue on the full-thickness skin excision site.HD-AM promoted early-phase inflammatory cell infiltration,fibroblast migration and angiogenesis in the granulation tissue.Additionally,the early infiltration of cells of the immune system was observed.Conclusions:HD-AM may be useful as a new wound dressing material for full-thickness skin excision sites after third-degree burn injuries,and may be a new therapeutic technique for improving the survival rate of patients with severe burn injuries.

Mineralized collagen scaffolds fabricated with amniotic membrane matrix increase osteogenesis under inflammatory conditions

Defects in craniofacial bones occur congenitally,after high-energy impacts,and during the course of treatment for stroke and cancer.These injuries are difficult to heal due to the overwhelming size of the injury area and the inflammatory environment surrounding the injury.Significant inflammatory response after injury may greatly inhibit regenerative healing.We have developed mineralized collagen scaffolds that can induce osteogenic differentiation and matrix biosynthesis in the absence of osteogenic media or supplemental proteins.The amniotic membrane is derived from placentas and has been recently investigated as an extracellular matrix to prevent chronic inflammation.Herein,we hypothesized that a mineralized collagen-amnion composite scaffold could increase osteogenic activity in the presence of inflammatory cytokines.We report mechanical properties of a mineralized collagen-amnion scaffold and investigated osteogenic differentiation and mineral deposition of porcine adipose-derived stem cells within these scaffolds as a function of inflammatory challenge.Incorporation of amniotic membrane matrix promotes osteogenesis similarly to un-modified mineralized collagen scaffolds,and increases in mineralized collagen-amnion scaffolds under inflammatory challenge.Together,these findings suggest that a mineralized collagen-amnion scaffold may provide a beneficial environment to aid craniomaxillofacial bone repair,especially in the course of defects presenting significant inflammatory complications.

Profiling the Bisecting N-acetylglucosamine Modification in Amniotic Membrane via Mass Spectrometry

Bisecting N-acetylglucosamine(GlcNAc),a GlcNAc linked to the coreβ-mannose residue via aβ1,4 linkage,is a special type of N-glycosylation that has been reported to be involved in various biological processes,such as cell adhesion and fetal development.This N-glycan structure is abundant in human trophoblasts,which is postulated to be resistant to natural killer cellmediated cytotoxicity,enabling a mother to nourish a fetus without rejection.In this study,we hypothesized that the human amniotic membrane,which serves as the last barrier for the fetus,may also express bisected-type glycans.To test this hypothesis,glycomic analysis of the human amniotic membrane was performed,and bisected N-glycans were detected.Furthermore,our proteomic data,which have been previously employed to explore human missing proteins,were analyzed and the presence of bisecting GlcNAc-modified peptides was confirmed.A total of 41glycoproteins with 43 glycopeptides were found to possess a bisecting GlcNAc,and 25 of these glycoproteins were reported to exhibit this type of modification for the first time.These results provide insights into the potential roles of bisecting GlcNAc modification in the human amniotic membrane,and can be beneficial to functional studies on glycoproteins with bisecting GlcNAc modifications and functional studies on immune suppression in human placenta.

Medical and surgical approach to ocular surface reconstruction

Ocular surface disease(OSD)can have a severe impact on patients as it can lead to visual impairment and persistent discomfort.Ocular surface reconstruction(OSR)is an approach to the management of ocular diseases that cause structural damage to the ocular surface.OSR encompasses both medical and surgical treatment options.In this review,we discuss the medical and surgical strategies used in OSR.Medical management often aims to treat tear insufficiency,inflammation,and keratinization.Surgical treatments may be employed for a variety of reasons,including failure of medical management.This may include improving the oculo-palpebral structures in order to improve lid positioning and tear film.Additional therapies focus on improving tear production,such as through salivary gland transplantation.In situations where the ocular surface is so severely damaged that there is loss of limbal stem cells,limbal stem cell transplant(LSCT)may be indicated.Other surgeries such as amniotic membrane transplant(AMT)and conjunctival flaps(CFs)can help promote corneal healing.Finally,in severe situations where the cornea is beyond salvage,corneal transplantation,such as a penetrating keratoplasty(PKP),can be considered.OSR often requires a combination of medical and surgical approaches targeted to each specific patient’s presentation in order to achieve optimal outcomes.