Ive mice per group. For glucose tolerance test, blood glucose levels had been measured after an intraperitoneal glucose injection of 1 g/kg physique weight. P 0.05 vs. Con. Information are representative of 3 independent experiments.percentage of hepatic CD8+ T cells was decreased in both CAG-IGF-I reated and CD68-IGF-I reated animals (Supplementary Fig. 4A, B). Importantly, no changes had been detected in PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/20078644 the frequency of peripheral macrophages, DCs or lymphocytes with either remedy (Supplementary Fig. 4C, D). The only exception was a reduce in circulating NK cells in the CAG-IGF-I group (Supplementary Fig. 4C). IGF-I treatment also led to a substantial enhance in liver CD11b+Gr1+ myeloid-derived suppressor cells (MDSCs), in each STZ-CAG-IGF-I and STZ-CD68-IGF-I mice 2 weeks post-STZ (Fig. 5C, D). Nevertheless, the percentage of CD11b+ cells remained unchanged (Fig. 5E). In addition to getting potent suppressors of a variety of T-cell functions, MDSCs can also induce Treg development (27). The percentage of hepatic DCs was also enhanced (Fig. 5F). To rule out the possibility that these differences had been attributable to adjustments in total cell numbers (e.g., presence of an inflammatory infiltrate in response to higher numbers of CpG motifs inside the IGF-I plasmid as compared with the noncoding one), the total amount of CD11b+ and CD11c+ cells was measured in a separate cohort of mice that received either CAG-IGF-I or noncoding plasmid and compared with an uninjected manage group. Importantly, each plasmid-treated groups had equivalent CD11b+ and CD11c+ cell numbers inside the liver (data not shown). To additional ascertain the effects of IGF-I expression on DCs, the DCs from livers of healthy mice were isolated and cultured in vitro in the presence of exogenous IGF-I and556 DIABETES, VOL. 62, FEBRUARYthe expression of essential immunosuppressive cytokines was analyzed by quantitative PCR. IGF-I-treated DCs showed an increase in transforming development element (TGF)-b and interleukin (IL)-7 expression, whereas IL-10 remained unchanged (Fig. 5G). TGF-b is critically involved in peripheral conversion of conventional T cells to Tregs (28), whereas IL-7 is usually a survival factor for Tregs and is expressed by diabetes-suppressive immature DCs (29). Roles of Treg and NK cells in diabetes modulation. Tregs play a major part in the control of kind 1 diabetes (30). To define if alterations in Tregs populations underlie the ability of hepatic IGF-I expression to defend from diabetes, we analyzed the percentage of intrahepatic and intrapancreatic Tregs soon after pCAG-IGF-I treatment. A substantial (around two-fold) increase of CD4+CD25+Foxp3+ Tregs within the pancreas of IGF-I-treated animals was found (Fig. 6A). A rise of about two-fold in intrahepatic Tregs, albeit nonsignificant, also was observed when compared with STZ-Con mice (Fig. 6B). The contribution of Tregs within the prevention of diabetes was additional studied by depleting this cell population with an anti-CD25 antibody as previously described (31). Treg depletion in the absence of STZ failed to trigger diabetes onset (Supplementary Fig. 5). As expected from previous experiments, IGF-I therapy ABBV-075 site prevented the development of diabetes in ;70 of STZ-treated mice, whereas the depletion of CD25+ lymphocytes totally abolished the IGF-I-mediated protective effect (Fig. 6C, leftdiabetes.diabetesjournals.orgX.M. ANGUELA AND ASSOCIATESFIG. 5. KC-derived but not hepatocyte-derived IGF-I protects islets from diabetes and increases.
