Zenbiohumanpre-ADIpocytes(adiposederivedadultstemcells)andplacentalmesenchymalstemcells(MSC)arecharacterizedbytheirself-renewingcapacityandABIlitytodifferentiateintochondrocytes,adipocytes,andosteocytes.Thismakesthemattractivestartingmaterialsfortissueengineeringandregenerativemedicineapplications.
Sincefewtransplantedcellspersistinvivo,thebeneficialeffectsofcelltherapymaylieinthesecretedfactorsbeingtheactivecomponentofthistreatment.AkeypartofparacrinesecretionisExosomes,whicharemembranevesiclesthatarestoredintracellularlyinendosomalcompartmentsandaresecretedwhenthesestructuresfusewiththecellplasmamembrane.
- Exosomescontainprotein,DNA,andRNA,thusmakingthemanattractivevectorofparacrinesignalsdeliveredbystemcells.
- Exosomesmayalsobe"loaded"withpredeterminedproteinsandnucleicacidtoachieveadesiredeffect(1).
- Exosomescanbestoredasan"off-the-shelf"producthavingthepotentialforcircumventingmanyofthelimitationsofviablecellsfortherapeuticapplicationsinregenerativemedicine.
- Invitro,exosomesfrompre-adipocytesstimulatecellproliferationinawoundhealingmodel.
- Invivo,adipose-graftderivedexosomeshavebeenshowntobeapromisingtoolforskinrepairandremodeling(2)
QualityControl:AllcellshavebeenscreenednegativeforHIV-1,HIV-2,Hep-B,Hep-CandSyphilis.AllisolatedandconcentratedexosomesundergoincludesParticlemeandiameter,Proteinconcentration,RNAconcentrationandConcentrationofparticles/ml.
Exosome-mediatedfibroblastproliferation
Afterthecellmonolayerwas"wounded"usingacellscraper,thecultureswerewashedandfedwithDMEM+10%exosome-freeFBS(Control),orDMEM+10%exosome-freeFBSsupplementedwith25µgofpre-adipocyteexosomes(ExosomeTreated).Aftera5dayincubation,fibroblastproliferationclosedthegapbetweenthetwoedgesofthewoundedmonolayeronlyinthemediumsupplementedwithexosomes.Thesedatasupportthenotionthatfactorsincludingexosomessecretedbypre-adipocytes(adiposetissue-derivedMSC)playaroleinwoundhealingandtissueregeneration,byfacilitatingcellularproliferation
