Cytokines in single layer amnion allografts compared to multilayer amnion/chorion allografts for wound healing

Abstract

Human amniotic membrane allografts have proven effective at improving healing of cutaneous wounds. The mechanism of action for these therapeutic effects is poorly understood but is thought to involve the resident growth factors present in near term amniotic tissue. To determine the relative cytokine contribution of the amnion and chorion in amniotic allografts, the content of 18 cytokines involved in wound healing were measured in samples of PURION V R Processed dehydrated amnion, chorion, and amnion/chorion membrane (dHACM) grafts by multiplex enzyme-linked immunosorbent assay array. Both amnion and chorion contained similar amounts of each factor when normalized per dry weight; however, when calculated per surface area of tissue applied to a wound, amnion contained on average only 25% as much of each factor as the chorion. Therefore, an allograft containing both amnion and chorion would contain four to five times more cytokine than a single layer amnion allograft alone. Both single layer amnion and multilayer allografts containing amnion and chorion are currently marketed for wound repair. To examine the role of tissue processing technique in cytokine retention, cytokine contents in representative dehydrated single layer wound care products were measured. The results demonstrated that cytokine content varied significantly among the allografts tested, and that PURION V R Processed single layer amnion grafts contained more cytokines than other single layer products. These results suggest that PURION V R Processed dHACM contains substantially more cytokines than single layer amnion products, and therefore dHACM may be more effective at delivering growth factors to a healing wound than amnion alone.

An investigational study of a dual‐layer, chorion‐free amnion patch as a protective barrier following lumbar laminectomy in a sheep model

“…The proinflammatory cytokines TNF‐α, TNF‐β, and TGF‐β1 were not detected in the amnion. This finding is contrary to other existing literature, which demonstrated these cytokines present in amnion (Koob et al, ; Sane, Misra, Quintanar, Jones, & Mustafi, ). Because cytokine expression is multifaceted, this result may be due to a number of different factors such as the presence of chorion, varying processing techniques, and different structural organization of patches used in the literature.…”

Characterisation of dehydrated amnion chorion membranes and evaluation of fibroblast and keratinocyte responses in vitro

“…Clinical studies of placental membranes have demonstrated improved outcomes in a variety of wound types, including: acute wounds, DFUs, and venous leg ulcers . Placental tissues are processed in various ways, including: cryopreservation, hypothermic storage, and dehydration . Composition and processing alters the proteomic composition and may consequently affect how the grafts function …”

“…Placental tissues are processed in various ways, including: cryopreservation, hypothermic storage, and dehydration . Composition and processing alters the proteomic composition and may consequently affect how the grafts function …”

A multicentre randomised controlled trial evaluating the efficacy of dehydrated human amnion/chorion membrane (EpiFix®) allograft for the treatment of venous leg ulcers

“…As there are limitations to every study, we acknowledge that our results may not be generalised to other amniotic membrane products seeing that scientific papers have been published describing differences among the products . It must also be recognised that all patients received a high level of care in a wound care centre.…”