12(S)-hydroxyeicosatetraenoic acid (12[S]-HETE) and 13(S)-hydroxyoctadecadienoic acid (13[S]-HODE), lipoxygenase metabolites of arachidonic acid and linoleic acid, respectively, previously have been suggested to regulate tumor cell adhesion to endothelium during metastasis. Adhesion of rat Walker carcinosarcoma (W256) cells to a rat endothelial cell monolayer was enhanced after treatment with 12(S)-HETE and this 12(S)-HETE enhanced adhesion was blocked by 13(S)-HODE. Protein kinase inhibitors, staurosporine, calphostin C, and 1-(5-isoquinoline-sulfonyl)-2-methylpiperazine, inhibited the 12(S)-HETE enhanced W256 cell adhesion. Depleting W256 cells of protein kinase C (PKC) with phorbol 12-myristate-13-acetate abolished their ability to respond to 12(S)-HETE. Treatment of W256 cells with 12(S)-HETE induced a 100% increase in membrane-associated PKC activity whereas 13(S)-HODE inhibited the effect of 12(S)-HETE on PKC translocation. High-performance liquid chromatographic analysis revealed that in W256 cells 12-HETE and 13-HODE were two of the major lipoxygenase metabilites of arachidonic acid and linoleic acid, respectively. Therefore, these two metabolites may provide an alternative signaling pathway for the regulation of PKC. Further, these findings suggest that the regulation of tumor cell adhesion to endothelium by 12(S)-HETE and 13(S)-HODE may be a PKC-dependent process.

BACKGROUND. Type 1 diabetes (T1D) results from loss of immune regulation, leading to the development of autoimmunity to pancreatic β cells, involving autoreactive T effector cells (Teffs). Tregs, which prevent autoimmunity, require IL-2 for maintenance of immunosuppressive functions. Using a response-adaptive design, we aimed to determine the optimal regimen of aldesleukin (recombinant human IL-2) to physiologically enhance Tregs while limiting expansion of Teffs. METHODS. DILfrequency is a nonrandomized, open-label, response-adaptive study of participants, aged 18-70 years, with T1D. The initial learning phase allocated 12 participants to 6 different predefined regimens. Then, 3 cohorts of 8 participants were sequentially allocated dose frequencies, based on repeated interim analyses of all accumulated trial data. The coprimary endpoints were percentage change in Tregs and Teffs and CD25 (α subunit of the IL-2 receptor) expression by Tregs, from baseline to steady state. RESULTS. Thirty-eight participants were enrolled, with thirty-six completing treatment. The optimal regimen to maintain a steady-state increase in Tregs of 30% and CD25 expression of 25% without Teff expansion is 0.26 × 10 6 IU/m 2 (95% CI-0.007 to 0.485) every 3 days. Tregs and CD25 were dose-frequency responsive, Teffs were not. The commonest adverse event was injection site reaction (464 of 694 events). CONCLUSIONS. Using a response-adaptive design, aldesleukin treatment can be optimized. Our methodology can generally be employed to immediately access proof of mechanism, thereby leading to more efficient and safe drug development.

This study suggests that CGM has sufficient accuracy and utility in preterm infants to warrant formal testing in a RCT.

IntroductionType 1 diabetes (T1D) is caused by autoimmune destruction of the insulin-producing β cells in the pancreatic islets, leading to insulinopenia and hyperglycaemia. Genetic analyses indicate that alterations of the interleukin-2 (IL-2) pathway mediating immune activation and tolerance predispose to T1D, specifically the polymorphic expression of the IL-2 receptor-α chain (CD25) on T lymphocytes. Replacement of physiological doses of IL-2 could restore self-tolerance and prevent further autoimmunity by enhancing the function of CD4+ T regulatory cells (Tregs) to limit the activation of auto reactive T effector cells (Teffs). In this experimental medicine study, we use an adaptive trial design to determine the optimal dosing regimen for IL-2 to improve Treg function while limiting activation of Teffs in participants with T1D.Methods and analysisThe Adaptive study of IL-2 dose frequency on Tregs in type 1 diabetes(DILfrequency) is a mechanistic, non-randomised, repeat dose open-label, response-adaptive study of 36 participants with T1D. The objective is to establish the optimal dose and frequency of ultra-low dose IL-2: to increase Treg frequency within the physiological range, to increase CD25 expression on Tregs, without increasing CD4+ Teffs. DILfrequency has an initial learning phase where 12 participants are allocated to six different doses and frequencies followed by an interim statistical analysis. After analysis of the learning phase, the Dose and Frequency Committee will select the optimal targets for Treg frequency, Treg CD25 expression and Teff frequency. Three groups of eight participants will be treated consecutively in the confirming phase. Each dose and frequency selected will be based on statistical analysis of all data collected from the previous groups.EthicsEthical approval for DILfrequency was granted on 12 August 2014.ResultsThe results of this study will be reported, through peer-reviewed journals, conference presentations and an internal organisational report.Trial registration numbersNCT02265809, ISRCTN40319192, CRN17571.