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Summary Granulocyte colony-stimulating factor (G-CSF) has been used to restore immune competence following chemoablative cancer therapy and to promote immunological tolerance in certain settings of autoimmunity. Therefore, we tested the potential of G-CSF to impact type 1 diabetes (T1D) progression in patients with recent-onset disease [n = 14; n = 7 (placebo)] and assessed safety, efficacy and mechanistic effects on the immune system. We hypothesized that pegylated G-CSF (6 mg administered subcutaneously every 2 weeks for 12 weeks) would promote regulatory T cell (Treg) mobilization to a degree capable of restoring immunological tolerance, thus preventing further decline in C-peptide production. Although treatment was well tolerated, G-CSF monotherapy did not affect C-peptide production, glycated haemoglobin (HbA1c) or insulin dose. Mechanistically, G-CSF treatment increased circulating neutrophils during the 12-week course of therapy (P < 0·01) but did not alter Treg frequencies. No effects were observed for CD4+ : CD8+ T cell ratio or the ratio of naive : memory (CD45RA+/CD45RO+) CD4+ T cells. As expected, manageable bone pain was common in subjects receiving G-CSF, but notably, no severe adverse events such as splenomegaly occurred. This study supports the continued exploration of G-CSF and other mobilizing agents in subjects with T1D, but only when combined with immunodepleting agents where synergistic mechanisms of action have previously demonstrated efficacy towards the preservation of C-peptide.

Background and aims Due to the unavailability of biologic porcine secretin (BPS), 2 synthetic forms of secretin were developed. Our aim is to determine the bioequivalency of the 3 forms of secretin in pancreatic function testing. Methods In a randomized, crossover design, synthetic porcine (SPS) and synthetic human secretin (SHS) were compared in a group of 12 subjects with chronic pancreatitis undergoing secretin stimulation test (SST). The 2 synthetic forms of secretin were then compared with BPS in 12 subjects utilizing a similar design. Finally, 18 healthy subjects underwent secretin stimulation testing with SHS. Results There was excellent correlation of peak bicarbonate measurements in the comparison of SPS to SHS (R = 0.967) as well as in the comparison of all 3 forms of secretin (P = 0.08, ANOVA for correlated samples). In the SST, each of the synthetic forms of secretin were 100% accurate in diagnosing chronic pancreatitis in disease subjects and in excluding chronic pancreatitis in normal controls. The synthetic forms of secretin were associated with fewer side effects when compared with BPS with the exception of transient tachycardia which occurred in up to 19% of subjects. Conclusions The synthetic porcine and human forms of secretin are equivalent to one another and to biologic porcine secretin and can be used interchangeably in pancreatic function testing.

OBJECTIVE We conducted an open-label, phase I study using autologous umbilical cord blood (UCB) infusion to ameliorate type 1 diabetes (T1D). Having previously reported on the first 15 patients reaching 1 year of follow-up, herein we report on the complete cohort after 2 years of follow-up. RESEARCH DESIGN AND METHODS A total of 24 T1D patients (median age 5.1 years) received a single intravenous infusion of autologous UCB cells and underwent metabolic and immunologic assessments. RESULTS No infusion-related adverse events were observed. β-Cell function declined after UCB infusion. Area under the curve C-peptide was 24.3% of baseline 1 year postinfusion (P < 0.001) and 2% of baseline 2 years after infusion (P < 0.001). Flow cytometry revealed increased regulatory T cells (Tregs) (P = 0.04) and naive Tregs (P = 0.001) 6 and 9 months after infusion, respectively. CONCLUSIONS Autologous UCB infusion in children with T1D is safe and induces changes in Treg frequency but fails to preserve C-peptide.

To examine the current extent of the obesity problem in 2 large pediatric clinical registries in the US and Europe and to examine the hypotheses that increased body mass index (BMI) z-scores (BMIz) are associated with greater hemoglobin A1c (HbA1c) and increased frequency of severe hypoglycemia in youth with type 1 diabetes (T1D).International (World Health Organization) and national (Centers for Disease Control and Prevention/German Health Interview and Examination Survey for Children and Adolescents) BMI references were used to calculate BMIz in participants (age 2-18 years and ≥ 1 year duration of T1D) enrolled in the T1D Exchange (n = 11,435) and the Diabetes Prospective Follow-up (n = 21,501). Associations between BMIz and HbA1c and severe hypoglycemia were assessed.Participants in both registries had median BMI values that were greater than international and their respective national reference values. BMIz was significantly greater in the T1D Exchange vs the Diabetes Prospective Follow-up (P.001). After stratification by age-group, no differences in BMI between registries existed for children 2-5 years, but differences were confirmed for 6- to 9-, 10- to 13-, and 14- to 17-year age groups (all P.001). Greater BMIz were significantly related to greater HbA1c levels and more frequent occurrence of severe hypoglycemia across the registries, although these associations may not be clinically relevant.Excessive weight is a common problem in children with T1D in Germany and Austria and, especially, in the US. Our data suggest that obesity contributes to the challenges in achieving optimal glycemic control in children and adolescents with T1D.

The secretin stimulation test is the most sensitive and specific test for pancreatic function. It is usually performed using biologically derived porcine secretin. Several shortages of biologic porcine secretin have occurred in the past few years. The aim of this study was to compare synthetic porcine secretin to biologic porcine secretin in pancreatic function testing in subjects with chronic pancreatitis. Twelve patients with a previously abnormal secretin stimulation test were enrolled. After an overnight fast, each patient underwent a secretin stimulation test on 2 consecutive days using 1 CU/kg biologic porcine secretin or 0.2 [microg/kg synthetic porcine secretin in a randomized fashion. The peak bicarbonate concentration in duodenal juice was used as a measure of pancreatic function. The peak bicarbonate concentration (mean +/- SD) obtained by using biologic porcine secretin and synthetic porcine secretin were 70 +/- 25 mEq/L and 68 +/- 31 mEq/L, respectively (p = 0.58, paired t test; R = 0.964). The accuracy of synthetic porcine secretin in diagnosing pancreatic insufficiency was 100% when compared with biologic porcine secretin. We conclude that synthetic porcine secretin is highly accurate and safe in pancreatic function testing. The 100% purity, excellent diagnostic accuracy, and ready availability make synthetic porcine secretin an attractive choice for secretin stimulation testing.

We sought to determine if autologous umbilical cord blood (UCB) infusion followed by 1 year of supplementation with vitamin D and docosahexaenoic acid (DHA) can preserve C-peptide in children with type 1 diabetes. We conducted an open-label, 2:1 randomized study in which 15 type 1 diabetes subjects with stimulated C-peptide > .2 pmol/mL received either (1) autologous UCB infusion, 1 year of daily oral vitamin D (2000 IU), and DHA (38 mg/kg) and intensive diabetes management or (2) intensive diabetes management alone. Primary analyses were performed 1 year after UCB infusion. Treated (N = 10) and control (N = 5) subjects had median ages of 7.2 and 6.6 years, respectively. No severe adverse events were observed. Although the absolute rate of C-peptide decline was slower in treated versus control subjects, intergroup comparisons failed to reach significance (P = .29). Area under the curve C-peptide declined and insulin use increased in both groups (P < .01). Vitamin D levels remained stable in treated subjects but declined in control subjects (P = .01). DHA levels rose in treated subjects versus control subjects (P = .003). CD4/CD8 ratio remained stable in treated subjects but declined in control subjects (P = .03). No changes were seen in regulatory T cell frequency, total CD4 counts, or autoantibody titers. Autologous UCB infusion followed by daily supplementation with vitamin D and DHA was safe but failed to preserve C-peptide. Lack of significance may reflect small sample size. Future efforts will require expansion of specific immunoregulatory cell subsets, optimization of combined immunoregulatory and anti-inflammatory agents, and larger study cohorts.

Bilateral ovariectomies or sham surgeries were performed in female Sprague Dawley rats that were 78 days of age and weighed an average of 210 g. Food was available ad libitum to the control rats and to a group of ovariectomized rats (obese OVX). The food consumption of a second group of ovariectomized rats (weight-matched OVX) was restricted to match their body weights to those of the control rats. All rats were sacrificed at 14 weeks postovariectomy. Radioimmunoassay of terminal serum estradiol confirmed the success of ovariectomy. The estradiol concentration in control rats was 24.9±20.2 pg/ml, whereas the hormone was undetectable (

The long-term skeletal effects of ovariectomy and aging were studied in female Sprague-Dawley rats sacrificed at 270, 370, and 540 days after bilateral ovariectomy (OVX) or sham surgery at 90 days of age. The proximal tibia was processed undecalcified for quantitative bone histomorphometry. For continuity, data from these late time points were combined with previously published data from earlier time points (0-180 days). A biphasic pattern of cancellous bone loss was detected in the proximal tibial metaphysis of OVX rats. An initial, rapid phase of bone loss out to 100 days was followed by an intermediate period of relative stabilization of cancellous bone volume at the markedly osteopenic level of 5-7%. After 270 days, a slow phase of bone loss occurred during which cancellous bone volume declined to 1-2%. Both the initial, rapid phase and the late, slow phase of bone loss in OVX rats were associated with increased bone turnover. In control rats, cancellous bone volume remained constant at 25-30% out to 270 days (12 months of age), then decreased to approximately 10% by 540 days (21 months of age). This age-related bone loss was also associated with increased bone turnover. It is interesting to note that the proximal tibial growth plates were closed in approximately a quarter of the control rats by 15-21 months of age. Our data indicate that a slow rate of bone loss and increased bone turnover persist in OVX rats during the later stages of estrogen deficiency. Therefore, the development of osteopenia is coincident with increased bone turnover in OVX rats as well as in aged, control rats.

Female Sprague-Dawley rats were subjected to bilateral ovariectomy (OVX) or sham surgery (control). Groups of ovariectomized (OVX) and control rats were injected daily with low, medium, or high doses of 17 beta-estradiol (10, 25, or 50 micrograms/kg BW, respectively). An additional group of OVX and control rats was injected daily with vehicle alone. All rats were killed 35 days after OVX, and their proximal tibiae were processed undecalcified for quantitative bone histomorphometry. Trabecular bone volume was markedly reduced in vehicle-treated OVX rats relative to that in control rats (12.1% vs. 26.7%). This bone loss was associated with a 2-fold increase in osteoclast surface and a 4-fold increase in osteoblast surface. The bone formation rate, studied with fluorochrome labeling, was also significantly elevated in vehicle-treated OVX rats (0.111 vs. 0.026 micron3/micron2.day). In contrast, treatment of OVX rats with the three doses of estradiol resulted in normalization of tibial trabecular bone volume and a decline in histomorphometric indices of bone resorption and formation. Our results indicate that estrogen treatment provides complete protection against osteopenia in OVX rats. The protective mechanism involves estrogenic suppression of bone turnover. These findings are consistent with the skeletal effects of estrogen therapy in postmenopausal women.