recombinant human cd26 dppiv protein  (R&D Systems)

Journal: Nature Communications

Article Title: Circadian fluctuation of soluble CD26 dictates the impact of the timing of cord blood transplantation on acute graft-versus-host disease

doi: 10.1038/s41467-026-68958-4

Figure Lengend Snippet: a Experimental design. Blood samples were collected at 7:00 am ± 15 min ( n = 10) or 11:30 am ± 15 min ( n = 10) from recipients with malignant hematological diseases in complete remission prior to cord blood infusion. b , c Serum concentrations of cytokines before cord blood infusion. Normalized z score ( b ) and absolute concentrations ( c ) of cytokines between 7:00 am and 11:30 am. The P values are two-sided and reported as exact values. d Absolute concentrations of soluble CD26/DPPIV in serum post-MAC. Blood samples were collected from recipients at 7:00 am ± 15 min ( n = 19), 11:30 am ± 15 min ( n = 19), or 4:00 pm ± 15 min ( n = 29). e – i Associations between serum soluble CD26/DPPIV (sCD26/DPPIV) levels and inflammatory cytokines before cord blood infusion on day 0. Pearson’s correlation coefficient ( r ) was calculated for the relationships between serum DPPIV levels and IL-1Ra ( e ) ( r = 0.476, P = 0.034), IL-1β ( f ) ( r = 0.450, P = 0.046), LIF ( g ) ( r = 0.517, P = 0.020), IL-18 ( h ) ( r = −0.811, P < 0.001) and IL-1α ( i ) ( r = 0.006, P = 0.741) concentrations. The P values are two-sided and reported as exact values.The data are presented as the means ± SEMs and were analyzed by unpaired t test followed by Bonferroni-Dunn correction ( c ), one-way ANOVA with Bonferroni multiple comparisons ( d ) and Pearson’s correlation ( e – i ). Source data are provided as a Source Data file.

Article Snippet: Cultures were maintained for 96 h in the presence of either recombinant human CD26/DPPIV protein (1000 ng/mL; 11244-SE, R&D Systems) or Sitagliptin phosphate monohydrate (200 μg/mL; S4002, Selleck).

Techniques:

Journal: Nature Communications

Article Title: Circadian fluctuation of soluble CD26 dictates the impact of the timing of cord blood transplantation on acute graft-versus-host disease

doi: 10.1038/s41467-026-68958-4

Figure Lengend Snippet: a , b Representative immunofluorescence images ( a ) and quantification ( b ) of CD26/DPPIV levels in intestinal epithelial cells from a healthy population at different times ( n = 3 patients per group) ( P < 0.001). Intestinal samples were collected at 10 am (CT10), 2 pm (CT14), and 6 pm (CT18). Scale bars, 50 μm. c Bmal1 and DPP4 expression in primary mouse epidermal cells postsynchronization in vitro ( n = 3 biological replicates, each from an independent primary culture prepared and synchronized on separate days). The Gapdh gene was used as an internal control. The relative expression levels were computed via the 2 −ΔΔCT method. CT6 is double plotted. d The concentration of CD26/DPPIV in the supernatant of primary mouse epidermal cells postsynchronization in vitro ( n = 3 biological replicates, each from an independent primary culture prepared and synchronized on separate days) ( P < 0.001). CT6 is double plotted. e Diurnal mRNA expression of DPP4 in mouse epidermal cells. Bmal1 ΔEC , epithelium cell-specific Bmal1 knockout mice. Statistics were obtained from a publicly available dataset ( GSE190035 ), with values representing the log2-transformed mean RPKM from 4 biological replicates per time point. ZT0 is double plotted.The data are presented as the means ± SEMs and were analyzed by one-way ANOVA with Bonferroni multiple comparisons ( b , d ) and JTK_Cycle ( c , e ). Source data are provided as a Source Data file.

Article Snippet: Cultures were maintained for 96 h in the presence of either recombinant human CD26/DPPIV protein (1000 ng/mL; 11244-SE, R&D Systems) or Sitagliptin phosphate monohydrate (200 μg/mL; S4002, Selleck).

Techniques: Immunofluorescence, Expressing, In Vitro, Control, Concentration Assay, Knock-Out, Transformation Assay

Journal: Nature Communications

Article Title: Circadian fluctuation of soluble CD26 dictates the impact of the timing of cord blood transplantation on acute graft-versus-host disease

doi: 10.1038/s41467-026-68958-4

Figure Lengend Snippet: PBMCs from healthy donors were cultured with PHA-L (control group), PHA-L plus CD26/DPPIV (sCD26 group), or PHA-L plus Sitagliptin (DPPIV inhibitor, DPPIVi group) for 72 h. a Experimental design. PBMCs from healthy donors were cultured with PHA-L (control group), PHA-L plus CD26/DPPIV (sCD26 group), or PHA-L plus Sitagliptin (DPPIV inhibitor, DPPIVi group) for 72 h. b , c Representative plots (left) and quantified percentages (right) of CD86 + ( b ) and CD80 + ( c ) CD14 + cells after 72 h of PBMCs coculture in different groups (pooled data from 8 healthy donors across four independent experiments). d – i Representative plots (left) and quantified percentages (right) of Ki-67 + , IFNγ + , and CD38 + cells among CD4 + T cells ( d , f , h ) and CD8 + T cells ( e , g , i ) after 72 h of PBMCs coculture in different groups (pooled data from 6 healthy donors across three independent experiments).The data are presented as the means ± SEMs and were analyzed by one-way ANOVA with the Bonferroni correction for multiple comparisons ( b – i ). All P values are two-sided and reported as exact values unless <0.001. Source data are provided as a Source Data file.

Article Snippet: Cultures were maintained for 96 h in the presence of either recombinant human CD26/DPPIV protein (1000 ng/mL; 11244-SE, R&D Systems) or Sitagliptin phosphate monohydrate (200 μg/mL; S4002, Selleck).

Techniques: Cell Culture, Control

Journal: Investigative Ophthalmology & Visual Science

Article Title: Dipeptidyl Peptidase 4, a Novel Adipokine, Impairs Retinal Microcirculation in Patients With Type 2 Diabetes Mellitus

doi: 10.1167/iovs.66.14.4

Figure Lengend Snippet: Effect of DPP4 intraluminal incubation on the BK-induced vasodilation of the retinal arterioles ( A ). The dose-dependent effect of DPP4 in response to BK is examined before (control, n = 16), and after intraluminal incubation with 100 ng/mL ( n = 4), 400 ng/mL ( n = 4), or 1 µg/mL ( n = 8) DPP4 for 3 hours ( B ). The time-course effect of DPP4 in response to BK is examined before (control), and after intraluminal incubation with 1 µg/mL DPP4 for 1, 2, and 3 hours ( n = 8). * P < 0.05 versus control.

Article Snippet: Human recombinant DPP4 was purchased from R&D Systems, and DPP4 inhibitor teneligliptin was obtained from Mitsubishi Tanabe Pharma Co., Ltd. (Osaka, Japan).

Techniques: Incubation, Control

Journal: Investigative Ophthalmology & Visual Science

Article Title: Dipeptidyl Peptidase 4, a Novel Adipokine, Impairs Retinal Microcirculation in Patients With Type 2 Diabetes Mellitus

doi: 10.1167/iovs.66.14.4

Figure Lengend Snippet: Effect of coadministration of DPP4 with superoxide scavenger, NADPH oxidase inhibitor, xanthine oxidase inhibitor, or DPP4 inhibitor ( A ). The dilation of the retinal arterioles to BK is examined before (control, n = 14) and after intraluminal incubation with 1 µg/mL DPP4 plus the superoxide anion scavenger TEMPOL (1 mM; n = 5), the NADPH oxidase inhibitor apocynin (100 µM; n = 4), or the xanthine oxidase inhibitor allopurinol (10 µM; n = 5) ( B ). Dilation of the retinal arterioles in response to BK is examined before (control, n = 5) and after intraluminal incubation with 1 µM plus the DPP4 inhibitor teneligliptin (0.5 µM; n = 5). * P < 0.05 versus control. † P < 0.05 versus DPP4 alone.

Article Snippet: Human recombinant DPP4 was purchased from R&D Systems, and DPP4 inhibitor teneligliptin was obtained from Mitsubishi Tanabe Pharma Co., Ltd. (Osaka, Japan).

Techniques: Control, Incubation

Journal: Small Science

Article Title: Sustained‐Release Sitagliptin Microneedles for Scar Prevention via Fibroblast‐to‐Adipocyte Conversion

doi: 10.1002/smsc.202500140

Figure Lengend Snippet: DPP4 − KMSCs exhibit higher adipogenic potential in vitro. A–D) Keloid tissues were collected, minced, and seeded to isolate and culture keloid‐derived fibroblasts (A). The isolated fibroblasts were then differentiated toward adipogenic (B), osteogenic (C), and chondrogenic fates (D). E) Surface marker expressions were analyzed using flow cytometry. F) Keloid‐derived DPP4 + and DPP4 − fibroblasts were sorted via fluorescence‐activated cell sorting. G) RT‐qPCR was performed to evaluate the mRNA level of OCT4 , MYC , SOX2 , and NANOG . n = 3; *, p < 0.05. H–J) Sorted DPP4 +/− fibroblasts underwent adipogenic induction, followed by Oil Red O staining and quantification analysis (H–I). Ten random fields per sample were analyzed. The mRNA levels of adipogenesis‐related genes were detected using RT‐qPCR (J); n = 3. Scale bars, 100 μm in (A, B, C, D, and H). Data are presented as mean ± SEM; statistical significance was determined by Student's t ‐test.

Article Snippet: To identify the direct truncation of IGF1 by DPP4, recombinant human IGF1 (rhIGF1, 291‐G1, R&D Systems, Minneapolis, MN) was incubated with a recombinant human DPP4 Fc chimera (11141‐SE, R&D Systems). rhDPP4/Fc was diluted to a concentration of 0.2 ng μL −1 in the assay buffer, and 1 μL of the diluted rhDPP4/Fc was added to 15 μL of diluted rhIGF1 (1 μg μL −1 ).

Techniques: In Vitro, Derivative Assay, Isolation, Marker, Flow Cytometry, Fluorescence, FACS, Quantitative RT-PCR, Staining

Journal: Small Science

Article Title: Sustained‐Release Sitagliptin Microneedles for Scar Prevention via Fibroblast‐to‐Adipocyte Conversion

doi: 10.1002/smsc.202500140

Figure Lengend Snippet: DPP4 − KMSCs demonstrate enhanced adipogenic capacity, whereas DPP4 + KMSCs demonstrate increased fibrotic capacity in vivo. FACS‐sorted DPP4 + and DPP4 − cells were subcutaneously transplanted into Balb/c nude mice. A) The volume of subcutaneously transplanted KMSCs in mice was measured, n = 9. B–D) Adipocyte formation was evaluated by (B) H&E staining (black arrow) and (C) immunofluorescence staining of Perilipin and HLA‐ABC. The black arrow indicates the newly formed adipocytes. (D) The numbers of adipocytes and immature adipocytes were analyzed; n = 6. E,F) Masson's trichrome staining and G,H) immunofluorescence staining of COL1A1 were performed to evaluate collagen deposition. The expression of I,J) PPARγ and K,L) CEBPα was examined by immunofluorescence staining. n = 6. **, p < 0.01. Scale bars, 200 μm in (B), 100 μm in (C), 20 μm in (E, G, I, and K). Data were presented as mean ± SEM. Statistical significance was determined by Student's t ‐test.

Article Snippet: To identify the direct truncation of IGF1 by DPP4, recombinant human IGF1 (rhIGF1, 291‐G1, R&D Systems, Minneapolis, MN) was incubated with a recombinant human DPP4 Fc chimera (11141‐SE, R&D Systems). rhDPP4/Fc was diluted to a concentration of 0.2 ng μL −1 in the assay buffer, and 1 μL of the diluted rhDPP4/Fc was added to 15 μL of diluted rhIGF1 (1 μg μL −1 ).

Techniques: In Vivo, Staining, Immunofluorescence, Expressing

Journal: Small Science

Article Title: Sustained‐Release Sitagliptin Microneedles for Scar Prevention via Fibroblast‐to‐Adipocyte Conversion

doi: 10.1002/smsc.202500140

Figure Lengend Snippet: Sitagliptin‐mediated adipogenic promotion is dependent on protection of IGF1 from DPP4 cleavage. A) Schematic of DPP4‐driven peptide/protein truncation. B–D) DPP4 directly truncates IGF1 but not BMP4. Recombinant human IGF‐I or BMP4 was incubated with recombinant human DPP4 Fc chimera for the cleaving assay, and the product was analyzed using HPLC‐MS/MS. (B) The peptide starting with “ETLC” (red arrow) represented the truncated product of IGF1 by DPP4 and (C) peptide starting with “KHHS” represented the truncated product of BMP4 by DPP4. (D) Percentages of truncated product from the cleaving assay were calculated. E–I) KMSCs underwent adipogenic induction and treated with sitagliptin (20 μM) or combined with the IGF‐1 signaling pathway inhibitor picropodophyllin (PPP, 50 nM), the mRNA and protein levels of adipogenesis‐related molecules were detected by RT‐qPCR E) and F–I) western blotting and quantification analysis. n = 3; *, p < 0.05, **, p < 0.01. Cont. medium, control medium, diff. medium, differentiation medium. Sitag, sitagliptin. M, marker. Data was presented as mean ± SEM. Statistical significance was determined by one‐way analysis of variance (ANOVA) followed by Tukey's HSD post hoc test.

Article Snippet: To identify the direct truncation of IGF1 by DPP4, recombinant human IGF1 (rhIGF1, 291‐G1, R&D Systems, Minneapolis, MN) was incubated with a recombinant human DPP4 Fc chimera (11141‐SE, R&D Systems). rhDPP4/Fc was diluted to a concentration of 0.2 ng μL −1 in the assay buffer, and 1 μL of the diluted rhDPP4/Fc was added to 15 μL of diluted rhIGF1 (1 μg μL −1 ).

Techniques: Recombinant, Incubation, Tandem Mass Spectroscopy, Quantitative RT-PCR, Western Blot, Control, Marker

Journal: Small Science

Article Title: Sustained‐Release Sitagliptin Microneedles for Scar Prevention via Fibroblast‐to‐Adipocyte Conversion

doi: 10.1002/smsc.202500140

Figure Lengend Snippet: Illustration of our work. In scar tissues, IGF1 is cleaved by DPP4 enzyme in DPP4 + KMSC. Cleaved IGF1 may induce KMSC differentiation toward myofibroblasts, whereas IGF1 protected by sitagliptin acts as an adipogenic agent.

Article Snippet: To identify the direct truncation of IGF1 by DPP4, recombinant human IGF1 (rhIGF1, 291‐G1, R&D Systems, Minneapolis, MN) was incubated with a recombinant human DPP4 Fc chimera (11141‐SE, R&D Systems). rhDPP4/Fc was diluted to a concentration of 0.2 ng μL −1 in the assay buffer, and 1 μL of the diluted rhDPP4/Fc was added to 15 μL of diluted rhIGF1 (1 μg μL −1 ).

Techniques: