English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

Recent studies have shown that adult skin incubated in low-Ca2+ (0.15 mM) medium rapidly degenerates but that normal architecture is maintained when the tissue is incubated in high-Ca2+ medium (1.4 mM Ca2+). To investigate whether the skin cell-produced growth factors insulin-like growth factor-1 (IGF-1) and epidermal growth factor (EGF) play a role in these events, 2-mm skin punch biopsies were obtained and maintained for 8 to 10 days in a basal medium containing 0.15 mM Ca2+ with and without growth factors, or containing 1.4 mM Ca2+ with and without antibodies to the same growth factors. In parallel experiments, cultured human keratinocytes were incubated for 2 days in the same basal medium in the presence or absence of the same growth factors and antibodies. Consistent with previous reports, organ cultures incubated in the low-Ca2+ (0.15 mM) medium rapidly degenerated. Neither IGF-1 nor EGF prevented the complete degeneration of epidermis and dermis in these organ cultures. Interestingly, the addition of an anti-IGF-1 receptor (IGF-1R) antibody to the organ cultures maintained in high-Ca2+ medium induced changes reminiscent of those seen when the organ cultures were maintained in low-Ca2+ medium, i.e. tissue degeneration. In contrast, antibodies to EGF receptor, used for comparison, only produced focal areas of epidermal necrosis. In vitro, IGF-1 is a known mitogen for keratinocytes. In cultured human keratinocytes, anti-IGF-1R antibody partially inhibited the IGF-1-mediated stimulation of human keratinocyte proliferation without affecting normal spontaneous growth. Additionally, IGF-1R immunolocalized to basal keratinocytes in vivo, exhibited specific binding to IGF-1 in vitro. This indicated a critical role for IGF-1R in both organ cultures ex vivo and cultured cells in vitro. Messenger RNA encoding both IGF-1 and IGF-1R were readily detected by RT-PCR in organ cultures incubated in both low- and high-Ca2+ medium. There were no detectable differences in IGF-1 mRNA in organ cultures growing in the low- or high-Ca2+ medium, but lower levels of IGF-1R mRNA were observed in the organ cultures maintained in low-Ca2+ medium than in those in high Ca2+ medium. These findings are consistent with homeostatic changes in the tissue grown under different calcium concentrations. IGF-1 mRNA was detected in several skin cell populations in vitro, even though it was undetectable in cultured keratinocytes. Taken together these findings indicate that (1) the IGF-1/ IGF-1R loop is critically involved in maintenance of human skin organ cultures ex vivo, and (2) IGF-1, locally produced by skin cells other than keratinocytes, interacts with its receptor, predominantly expressed in basal keratinocytes, to maintain tissue homeostasis.

Maintenance of human skin in organ culture: role for insulin-like growth factor-1 receptor and epidermal growth factor receptor