Abstract
Abstract: :
Purpose: The aim of our study was to investigate presence, production and release of NGF by human amniotic membrane (AM) and the role of NGF in the modulation of production and release of IL-2, IL-10, IFNγ, TGFß. Methods: Presence and production of NGF by AMs were evaluated by imunohistochemistry, in situ hybridization, ELISA and RT-PCR. Immunohistochemistry was performed to evaluate the presence of NGF receptors (TrkA, p75) on AM. Six AM were divided in three parts and cultivated in modified D-MEM or in D-MEM supplemented with antibody neutralizing endogenous NGF (1 µg/ml), or supplemented with exogenous NGF (250 pg/ml). After 40 hrs. in culture the AMs were evaluated for cytokines presence and release in the medium by specific ELISA. Results: NGF was produced and present (6.0 1.3 pg/g) in AM epithelium. Indeed both NGF receptors were expressed in the AM epithelium. In culture all the evaluated cytokines (IL-2, IL-10, IFNγ, TGFß) were measurable by ELISA in AM and medium. Preliminary data shows that exogenous NGF modulates cytokines production by AM inducing an increase of IFNγ in the tissue and medium, while the inhibition of endogenous NGF induces a decrease of IFNγ. Conclusion: We conclude that NGF is one of the growth factors released by the AM in vitro. We postulate that this neurotrophin could be responsible for part of the anti-inflammatory activity of the amniotic membrane.
Keywords: 423 growth factors/growth factor receptors • 435 immunomodulation/immunoregulation • 380 cytokines/chemokines