recombinant mouse igf1  (R&D Systems)

Journal: bioRxiv

Article Title: A Wnt-responsive fibrocartilage progenitor system coordinates postnatal mandibular condylar cartilage growth

doi: 10.64898/2026.03.25.714159

Figure Lengend Snippet: (A) Differential gene expression analysis was performed comparing H2B–EGFP –positive and H2B–EGFP –negative cells within the MC-progenitor cluster identified by single-cell RNA sequencing. Genes are ranked by statistical significance. Foxm1 is significantly enriched in the H2B–EGFP –positive population, whereas Tgfb1 is enriched in the H2B–EGFP –negative population, indicating divergent transcriptional programs associated with Wnt activity. (B) Feature plots were generated to visualize expression of representative genes across mandibular condylar cartilage populations. Wnt-responsive cells show enriched expression of Foxm1 and IGF signaling–related genes ( Igf1 , Igf1r , Igfbp4 , Igfbp7 ), whereas Wnt-low populations express Tgfb1 and related factors ( Igf2r , Igfbp5 , Igfbp6 ), supporting distinct signaling states. (C) Western blot analysis was performed in isolated Wnt-responsive cells transfected with control vector or constitutively active β-catenin (S33Y). Cells were stimulated with recombinant IGF1 for the indicated time points. β-catenin activation enhances Foxm1 expression and downstream mitogenic signaling, including ERK and IGF1R phosphorylation, indicating that β-catenin promotes proliferative signaling responses. (D) Co-immunoprecipitation was performed to assess interaction between β-catenin and Foxm1. Cell lysates immunoprecipitated with anti–β-catenin antibody show enrichment of Foxm1 compared with control IgG, indicating a physical association between β-catenin and Foxm1. (E,F) Histological and immunofluorescence analyses were performed on mandibular condyles from control and Axin2 CreERT2 ;Ctnnb1 fl/+ ;Foxm1 fl/+ compound heterozygous mice at P42. H&E staining reveals reduced fibrocartilage thickness, and Ki67 staining shows decreased proliferative activity, indicating cooperative effects of β-catenin and Foxm1 in maintaining fibrocartilage proliferation. Scale bar, 100 μm. (G) Quantification of fibrocartilage thickness and Ki67-positive cells was performed. Compound heterozygous mice show reduced fibrocartilage thickness and decreased proliferation compared with controls. Data are presented as mean ± s.d. Each dot represents one biologically independent animal. (H,I) Histological and immunofluorescence analyses were performed on mandibular condyles from control and Axin2 CreERT2 ;Foxm1 fl/fl mice at P42. Foxm1 deletion results in marked condylar hypoplasia and reduced proliferative activity, indicating a critical role for Foxm1 in fibrocartilage growth. Scale bar, 100 μm. (J) Quantification of cartilage thickness and proliferative indices was performed in Foxm1 conditional knockout mice. Foxm1 deficiency significantly reduces cartilage growth and proliferation. Data are presented as mean ± s.d. Each dot represents one biologically independent animal. Statistical significance was assessed using two-tailed Student’s t-test. n.s., not significant; **P < 0.01; ****P < 0.0001. Abbreviations: sz, superficial zone; fc, fibrocartilage zone; cc, chondrocartilage zone.

Article Snippet: Cells were stimulated with recombinant mouse IGF1 (Cat No. 791-MG-050, R&D systems) for 0, 30, 60, or 180 min.

Techniques: Gene Expression, Single Cell, RNA Sequencing, Activity Assay, Generated, Expressing, Western Blot, Isolation, Transfection, Control, Plasmid Preparation, Recombinant, Activation Assay, Phospho-proteomics, Immunoprecipitation, Immunofluorescence, Staining, Knock-Out, Two Tailed Test

Journal: bioRxiv

Article Title: A Wnt-responsive fibrocartilage progenitor system coordinates postnatal mandibular condylar cartilage growth

doi: 10.64898/2026.03.25.714159

Figure Lengend Snippet: (A) RNAscope in situ hybridization showing Foxm1 transcript localization within the fibrocartilage compartment of the mandibular condyle. (B) RNAscope detection of Igf1 transcripts enriched in the superficial region of the fibrocartilage layer. (C) Violin plot comparing Foxm1 expression between H2B-EGFP –positive and H2B-EGFP –negative cells within the MC-progenitor cluster. Scale bars: 100 μm.

Article Snippet: Cells were stimulated with recombinant mouse IGF1 (Cat No. 791-MG-050, R&D systems) for 0, 30, 60, or 180 min.

Techniques: RNAscope, In Situ Hybridization, Expressing

Journal: Development (Cambridge, England)

Article Title: Kupffer cells control neonatal hepatic metabolism via Igf1 signaling

doi: 10.1242/dev.204962

Figure Lengend Snippet: KC-hepatocyte crosstalk is altered in P0 KO Spi1 livers. (A) Bar plot showing the relative information flow of between WT Spi1 and KO Spi1 of inferred cell–cell communication using CellChat. (B) Comparison of the significant ligand–receptor pairs between WT Spi1 and KO Spi1 , which contribute to the signaling from KCs to the hepatocyte clusters. (C) Heatmap showing the relative importance of KC and hepatocyte clusters as sender, receiver, mediator and influencer, based on the computed four network centrality measures of IGF (top) and visfatin (bottom) signaling. (D) Box plot of variance stabilizing transformation-normalized Igf1 expression in hepatocytes and macrophages in WT Spi1 and KO Spi1 mice at P0. n =5 per genotype from 3 independent litters. Differential expression was tested using DESeq2 on raw counts. The whiskers represent the 5-95% percentile, the box extends from the 25th to 75th percentiles and the horizontal line represents the median. (E) Serum insulin levels measured by ELISA on WT Spi1 and KO Spi1 at P0. n =4-5 per genotype from 4 independent litters. Bar plot presented as mean±s.d. Unpaired Student's t -test. (F) Serum glucagon levels measured by ELISA on WT Spi1 and KO Spi1 at P0. n =6 per genotype from 3 independent litters. Bar plot presented as mean±s.d. Unpaired Student's t -test. (G) Enrichment analysis of downregulated phosphorylation sites showing the decreased and increased phosphorylation in KO Spi1 liver compared to WT Spi1 . n =4-6 per genotype from 5 independent litters.

Article Snippet: Recombinant Igf1 protein (R&D Systems, 791-MG) was added in the same way at a final concentration of 100 ng/ml.

Techniques: Comparison, Transformation Assay, Expressing, Quantitative Proteomics, Enzyme-linked Immunosorbent Assay, Phospho-proteomics

Journal: Development (Cambridge, England)

Article Title: Kupffer cells control neonatal hepatic metabolism via Igf1 signaling

doi: 10.1242/dev.204962

Figure Lengend Snippet: KC-derived Igf1 regulates glycogen homeostasis in hepatocytes at birth. (A) Percentage of (left) and normalized (right) Igf1 expression in the respective hepatic cell type during embryogenesis. (B) Breeding scheme to produce KO Igf1 mice and littermate controls ( WT Igf1 ). Created in BioRender by Mass, E., 2025. https://BioRender.com/jvsfc8p . This figure was sublicensed under CC-BY 4.0 terms. (C,D) Igf1 levels measured by ELISA on whole liver lysate (C) and serum (D) of WT Igf1 and KO Igf1 at P0. n =7-8 per genotype from 4 independent litters. Bar plots presented as mean±s.d. Unpaired Student's t -test. (E) Glycogen levels measured on whole liver lysates of WT Igf1 and KO Igf1 at P0. n =11-16 per genotype from 7 independent litters. Values were normalized per litter. The whiskers represent the 5-95% percentile, the box extends from the 25th to 75th percentiles and the horizontal line represents the median. Cross indicates the mean. Mann–Whitney test. (F) Representative transmission electron micrograph from WT Igf1 and KO Igf1 livers at P0. n =3-4 per genotype from 2 independent litters. GP, glycogen particle; N, nucleus. Scale bars: 8 µm. (G) Scheme indicating the quantification process of glycogen content in hepatocytes. (H) Hepatocyte glycogen content of KO Igf1 normalized to WT Igf1 littermates; each value represents one hepatocyte (ten hepatocytes were assessed per liver). n =3-4 per genotype from 2 independent litters. Mann–Whitney test. (I) Normalized total metabolite abundance in WT Igf1 and KO Igf1 livers following [U- 13 C 6 ]-glucose tracing at P0. n =5-6 per genotype from 2 independent litters. Unpaired Student's t -test. ns, not significant ( P >0.05). (J) Fractional enrichment of labeled metabolites following [U- 13 C 6 ]-glucose tracing at P0 with and without the addition of exogenous Igf1 protein. Liver samples with and without Igf1 from the same animal are connected with a line. n =5-6 per genotype from 2 independent litters. Wilcoxon test.

Article Snippet: Recombinant Igf1 protein (R&D Systems, 791-MG) was added in the same way at a final concentration of 100 ng/ml.

Techniques: Derivative Assay, Expressing, Enzyme-linked Immunosorbent Assay, MANN-WHITNEY, Transmission Assay, Labeling