Attenuation of periostin in retinal Müller glia by TNF-α and IFN-γ

Transcriptomics of CD29+/CD44+ cells isolated from hPSC retinal organoids reveals a single cell population with retinal progenitor and Müller glia characteristics

Müller glia play very important and diverse roles in retinal homeostasis and disease. Although much is known of the physiological and morphological properties of mammalian Müller glia, there is still the need to further understand the profile of these cells during human retinal development. Using human embryonic stem cell-derived retinal organoids, we investigated the transcriptomic profiles of CD29+/CD44+ cells isolated from early and late stages of organoid development. Data showed that these cells express classic markers of retinal progenitors and Müller glia, including NFIX, RAX, PAX6, VSX2, HES1, WNT2B, SOX, NR2F1/2, ASCL1 and VIM, as early as days 10-20 after initiation of retinal differentiation. Expression of genes upregulated in CD29+/CD44+ cells isolated at later stages of organoid development (days 50-90), including NEUROG1, VSX2 and ASCL1 were gradually increased as retinal organoid maturation progressed. Based on the current observations that CD24+/CD44+ cells share the characteristics of early and late-stage retinal progenitors as well as of mature Müller glia, we propose that these cells constitute a single cell population that upon exposure to developmental cues regulates its gene expression to adapt to functions exerted by Müller glia in the postnatal and mature retina.

Periostin in Angiogenesis and Inflammation in CRC-A Preliminary Observational Study

Background and Objectives: To assess the periostin level and the concentrations of pro-inflammatory cytokines: TNFα, IFN-γ, IL-1β and IL-17 in tumor and marginal tissues of CRC and to investigate the influence of periostin on angiogenesis by MVD (microvessel density) and concentration of VEGF-A in relation to clinicopathological parameters of patients. Materials and Methods: The study used 47 samples of tumor and margin tissues derived from CRC patients. To determinate the concentration of periostin, VEGF-A, TNFα, IFNγ, IL-1β and IL-17, we used the commercially available enzyme- linked immunosorbent assay kit. MVD was assessed on CD34-stained specimens. The MVD and budding were assessed using a light microscope Results: We found significantly higher concentrations of periostin, VEGF-A, IFN-γ, IL-1 β, IL-17 and TNFα in the tumor samples compared with surgical tissue margins. The tumor concentrations of periostin were correlated with tumor levels of VEGF-A, IFN-γ, IL-1β and TNFα. We observed significant correlation between margin periostin and VEGF-A, IFN-γ, IL-17 and TNFα in tumor and margin specimens. Additionally, we found a significantly negative correlation between periostin tumor concentration and microvessel density at the invasive front. Tumor periostin levels were also correlated positively with tumor budding. Conclusions: Periostin activity may be associated with pro-inflammatory cytokine levels: TNFα, IFN-γ, IL-1β and IL-17. Our results also suggest the role of periostin in angiogenesis in CRC and its upregulation in poorly vascularized tumors. Further research on the regulations between periostin and cytokines are necessary to understand the interactions between tumor and immune tumor microenvironment, which could be helpful in the development of new targeted therapy.