Amniotic Membrane Modifies the Genetic Program Induced by TGFß, Stimulating Keratinocyte Proliferation and Migration in Chronic Wounds.
BACKGROUND
Post-traumatic large-surface or deep wounds often cannot progress to reepithelialisation because they become irresponsive in the inflammatory stage, so intervention is necessary to provide the final sealing epidermis. Previously we have shown that Amniotic Membrane (AM) induced a robust epithelialisation in deep traumatic wounds.


RESULTS
To better understand this phenomenon, we used keratinocytes to investigate the effect of AM on chronic wounds. Using keratinocytes, we saw that AM treatment is able to exert an attenuating effect upon Smad2 and Smad3 TGFß-induced phosphorylation while triggering the activation of several MAPK signalling pathways, including ERK and JNK1, 2. This also has a consequence for TGFß-induced regulation on cell cycle control key players CDK1A (p21) and CDK2B (p15). The study of a wider set of TGFß regulated genes showed that the effect of AM was not wide but very concrete for some genes. TGFß exerted a powerful cell cycle arrest; the presence of AM however prevented TGFß-induced cell cycle arrest. Moreover, AM induced a powerful cell migration response that correlates well with the expression of c-Jun protein at the border of the healing assay. Consistently, the treatment with AM of human chronic wounds induced a robust expression of c-Jun at the wound border.


CONCLUSIONS
The effect of AM on the modulation of TGFß responses in keratinocytes that favours proliferation together with AM-induced keratinocyte migration is the perfect match that allows chronic wounds to move on from their non-healing state and progress into epithelialization. Our results may explain why the application of AM on chronic wounds is able to promote epithelialisation.
Oncología Molecular y TGFß, Unidad de Investigación, Hospital Universitario Virgen de la Arrixaca, El Palmar, Murcia, Spain.
Antonia
A
Alcaraz
Oncología Molecular y TGFß, Unidad de Investigación, Hospital Universitario Virgen de la Arrixaca, El Palmar, Murcia, Spain.
Anna
A
Mrowiec
Unidad de Terapia Celular, Hospital Clínico Universitario Virgen de la Arrixaca, El Palmar, Murcia, Spain.
Carmen Luisa
CL
Insausti
Oncología Molecular y TGFß, Unidad de Investigación, Hospital Universitario Virgen de la Arrixaca, El Palmar, Murcia, Spain.
Ángel
Á
Bernabé-García
Oncología Molecular y TGFß, Unidad de Investigación, Hospital Universitario Virgen de la Arrixaca, El Palmar, Murcia, Spain.
Eva María
EM
García-Vizcaíno
Oncología Molecular y TGFß, Unidad de Investigación, Hospital Universitario Virgen de la Arrixaca, El Palmar, Murcia, Spain.
María Concepción
MC
López-Martínez
Instituto Biodonostia, Hospital Universitario Donostia, San Sebastian, Spain.
Asunción
A
Monfort
Instituto Biodonostia, Hospital Universitario Donostia, San Sebastian, Spain.
Ander
A
Izeta
Unidad de Terapia Celular, Hospital Clínico Universitario Virgen de la Arrixaca, El Palmar, Murcia, Spain.
José María
JM
Moraleda
Servicio de Cirugía, Hospital Universitario Virgen de la Arrixaca, El Palmar, Murcia, Spain.
Gregorio
G
Castellanos
Oncología Molecular y TGFß, Unidad de Investigación, Hospital Universitario Virgen de la Arrixaca, El Palmar, Murcia, Spain.
Francisco José
FJ
Nicolás
D000650:Amnion / Q000166:cytology* / Q000378:metabolism; D000818:Animals; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D015603:Keratinocytes / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D008168:Lung / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D020935:MAP Kinase Signaling System; D008907:Mink; D010766:Phosphorylation; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D062326:Re-Epithelialization; D051899:Smad2 Protein / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D014945:Wound Healing / Q000187:drug effects / Q000502:physiology*; D014950:Wounds, Penetrating / Q000473:pathology / Q000628:therapy*
D016755:Proto-Oncogene Proteins c-jun; C497782:SMAD2 protein, human; D051899:Smad2 Protein; D016212:Transforming Growth Factor beta