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