Abidi, A. | bioRxiv Science

bioRxiv2025

CRISPR/Cas9-mediated generation of two isogenic CEP290-mutated iPSC lines

CEP290 is an important human disease gene, as mutations are implicated in a broad spectrum of autosomal recessive ciliopathies, including Leber congenital amaurosis and Joubert, Meckel, Senior-LOken or Bardet Biedl syndromes. To create isogenic mutant human induced pluripotent stem cell (hiPSC) lines for disease modeling, we employed CRISPR/Cas9 to introduce disease-relevant mutations into the control hiPSC line HMGU1 (ISFi001-A). Thorough characterization of the lines, including the effect of the mutation at the mRNA and protein level, shows that these CEP290-mutant lines provide a useful resource for studying ciliopathy disease mechanisms and cilia biology through differentiation into diverse cell types and organoids.

developmental biology↗

bioRxiv2021

Characterization of IL-22BP expression during Crohn's disease shows lack of evidence for IL-22BP production by T cells

Crohns disease (CD), a form of inflammatory bowel disease (IBD), is characterized by impaired epithelial barrier functions and dysregulated mucosal immune responses. IL-22 binding protein (IL-22BP) is a soluble inhibitor regulating IL-22 bioactivity, a cytokine proposed to play protective roles during CD. We and others have shown that IL-22BP is produced in IBD inflamed tissues, hence suggesting a role in CD. In this work, we extended the characterization of IL-22BP production and distribution in CD tissues by applying enzyme-linked immunosorbent assays to supernatants obtained from the culture of endoscopic biopsies of patients, and reverse transcription-quantitative polymerase chain reaction on sorted immune cell subsets. We reveal that IL-22BP levels are higher in inflamed ileums than colons. We observe that in a cell-intrinsic fashion, populations of mononuclear phagocytes and eosinophils express IL-22BP at the highest levels in comparison to other sources of T cells. We suggest the enrichment of intestinal eosinophils could explain higher IL-22BP levels in the ileum. In inflamed colon, we reveal the presence of increased IL-22/IL22BP ratios compared to controls, and a strong correlation between IL-22BP and CCL24. We identify monocyte-derived dendritic cells (moDC) as a cellular subtype co-expressing both cytokines and validate our finding using in vitro culture systems. We also show that retinoic acid induces the secretion of both IL-22BP and CCL24 by moDC. Finally, we report on higher IL-22BP levels in active smokers. In conclusion, our work provides new information relevant to therapeutic strategies modulating IL-22 bioactivity in CD, especially in the context of disease location.

immunology↗