A Chemically Inducible Helper Module for Detecting Protein–Protein Interactions with Tunable Sensitivity Based on KIPPIS

As protein–protein interactions (PPIs) play essential roles in regulating their functional consequences in cells, methods to detect PPIs in living cells are desired for correct understanding of intracellular PPIs and pharmaceutical development therefrom. Here we demonstrate a c-kit-based PPI screening (KIPPIS) system in combination with a chemically inducible helper module for detecting PPIs in living mammalian cells. In this system, a mutant of FK506-binding protein 12 (FKBP_F36 V) is fused with a protein of interest and the intracellular domain of a receptor tyrosine kinase c-kit. Constitutive expression of two fusion proteins with interacting proteins of interest in interleukin-3 (IL-3)-dependent cells results in dimerization and subsequent activation of the c-kit intracellular domains, which allows cell proliferation in a culture medium devoid of IL-3. A helper ligand, a small synthetic chemical that homodimerizes FKBP_F36 V, assists the formation of stable complexes of the fusion proteins and serves as a tuner for sensitivity of the system. Using this system, two model PPIs were successfully detected on the basis of cell proliferation, which was featured by the helper-ligand- and PPI-dependent phosphorylation of the Src family kinases, a hallmark of the c-kit signaling. Notably, the inclusion of the helper module enabled PPI detection with tunable sensitivity. The helper-assisted KIPPIS allows us to configure various affinity thresholds by changing the concentration of the helper ligand, which may be applied to select affinity-matured variants using the advantage of cell proliferation

Designing Motif-Engineered Receptors To Elucidate Signaling Molecules Important for Proliferation of Hematopoietic Stem Cells

The understanding of signaling events is critical for attaining long-term expansion of hematopoietic stem cells <i>ex vivo</i>. In this study, we aim to analyze the contribution of multiple signaling molecules in proliferation of hematopoietic stem cells. To this end, we design a bottom-up engineered receptor with multiple tyrosine motifs, which can recruit multiple signaling molecules of interest. This is followed by a top-down approach, where one of the multiple tyrosine motifs in the bottom-up engineered receptor is functionally knocked out by tyrosine-to-phenylalanine mutation. The combination of these two approaches demonstrates the importance of Shc in cooperation with STAT3 or STAT5 in the proliferation of hematopoietic stem cells. The platform developed herein may be applied for analyzing other cells and/or other cell fate regulation systems

Effect of nanoparticle curcumin on the fecal short-chain fatty acid (SCFA) levels.

<p>The concentrations of fecal SCFAs were measured by high-performance liquid chromatography. The data were expressed as means ± SEM (n = 6 mice/group). Values not sharing a letter are significantly different (<i>P</i><0.05).</p

The effects of nanoparticle curcumin on the induction of Tregs and regulatory DCs in the lamina propria of the colon.

<p>(A) Flow cytometry analysis for CD4⁺ Foxp3⁺ Tregs in the lamina propria of the colon. Representative picture from two independent experiments. (B) Proportion of CD4⁺ Foxp3⁺ Treg cells in CD4⁺ cells in the lamina propria. The data are expressed as means ± SEM (n = 6 mice/group). Values not sharing a letter are significantly different (<i>P</i><0.05). (C) Flow cytometry analysis for CD103⁺ CD8α⁻ DCs in the lamina propria of the colon. Representative picture from two independent experiments. (D) Proportion of CD103⁺ CD8α⁻ DCs in CD11c⁺ cells in the lamina propria. The data are expressed as means ± SEM (n = 6 mice/group). Values not sharing a letter are significantly different (<i>P</i><0.05).</p

Effect of nanoparticle curcumin on the development of DSS colitis.

<p>BALB/cAJcl mice were treated with nanoparticle curcumin (Theracurmin) for 7 days prior to the start of 3% DSS treatment. The mice were sacrificed on day 18. (A) Body weight. (B) Disease activity index. (C) Representative photographs of the colon. (D) Colonic weight/length on day 18. The data are expressed as means ± SEM (n = 6 mice/group). The data are representative of four independent experiments. Values not sharing a letter are significantly different (<i>P</i><0.05).</p

Histological evaluation of colitis.

<p>(A) Histological picture of the colonic tissue on day 18. (original magnification ×200.) (B) Histological sore. The data are expressed as means ± SEM (n = 6 mice/group). (C) Epithelial permeability. Mice were orally administrated with FITC-labeled dextran (44 mg/100 g body weight), (MW 4000; FD4, Sigma-Aldrich Co.). Serum was collected 5 h later and fluorescence intensity was determined. Values not sharing a letter are significantly different (<i>P</i><0.05).</p

The effect of nanoparticle curcumin on NF-κB activation.

<p>(A) Immunoblot for NF-κBp65 in the nuclear protein of colonic epithelium. Lamin A/C was used as a loading control. The picture is representative of four independent experiments. (B) Immunohistochemical staining for NF-κBp65 in the tissues. (original magnification ×200). NF-κBp65 was detected in the nucleus of the epithelial cells in the DSS group, but this was completely blocked in the DSS plus nanoparticle curcumin group. (C) Immunostaining of NF-κBp65 in HT-29 cells. HT-29 cells were stimulated with TNF-α (100ng/ml) in the presence or absence of nanoparticle curcumin (10μM) for 15 minutes. NF-κB p65, green fluorescence; nucleus, DAPI (blue). (D) The effect of nanoparticle curcumin on IκBα phosphorylation in response to TNF-α. HT-29 cells were stimulated with TNF-α (100 ng/ml) in the presence or absence of nanoparticle curcumin (0μM, 10μM, or 50μM) for 15 minutes, and then lysed with lysis buffer. Lysates were subjected to immunoblot analysis. GAPDH were used as loading control. The data represent four independent experiments.</p

The effect of nanoparticle curcumin on the gut microbial structure.

<p>(A) T-RFLP analysis of the gut microbiota. The value indicates the percentage of the predicted bacteria. (B) Real-time PCR analysis for <i>Clostridium</i> cluster IV. (C) Real-time PCR analysis for <i>Clostridium</i> subcluster XIVa. The values were normalized to the amount of total bacteria, and presented as relative amount to the control group. The data were expressed as means ± SEM (n = 4 mice/group). Values not sharing a letter are significantly different (<i>P</i><0.05).</p

Effects of nanoparticle curcumin on fecal microbial composition.

<p>Effects of nanoparticle curcumin on fecal microbial composition.</p

Changes in Rectal Dose Due to Alterations in Beam Angles for Setup Uncertainty and Range Uncertainty in Carbon-Ion Radiotherapy for Prostate Cancer - Fig 3

<p>Data on one patient without a metal implant, for four field angles: (a) 0° field, (b) 30° field, (c) 60° field, and (d) 90° field. Green line shows prostate, light yellow line shows PTV, and magenta line shows rectum. (i) Dose distribution in the normal case. (ii) Yellow line shows the 95% isodose line for the prescription dose in the normal case, blue line shows the 95% isodose line of the prescription dose in the worst case, and red line shows the 95% isodose line of the prescription dose in the best case.</p