3). Furthermore, the same treatment regimen reduced significantly the levels of IFN-γ, IL-1β, IL-2, IL-17 and TNF-α both in the spleen and pancreatic lymph nodes compared to control mice (Fig. 4a,b). The same differences, with the exception of TNF-α being undetectable, were also observed in murine sera in the same experimental conditions (Fig. 4c). Finally, prolonged treatment with apoTf did not change significantly the proportion of splenic CD4+ regulatory T cells (Treg) (CD4+/CD25+/FoxP3+) cells compared to control mice (Fig. 5). ApoTf plasma levels were significantly lower in patients with Omipalisib ND-type 1 diabetes compared to matched
controls, while this difference was not observed comparing patients with CR or LS disease (Fig. 6).When biochemical and clinical features of ND-type 1
diabetes were correlated with apoTf levels we found a significant association with HbA1c determined at disease onset using both laboratory methods (r = −0·452, P = 0·045 with RID; r = −0·564, P = 0·01 with nephelometry) but not with basal or stimulated C peptide levels, SP600125 GADA and IA2 antibodies, weight loss prior to diagnosis or symptom duration (data not shown). No correlation with any of the analysed clinical and biochemical features was encountered in patients with LS or CR type 1 diabetes (data not shown). The data presented herein were obtained from different murine and cellular models as well as human samples to demonstrate for the first time that recombinant human apoTf or human-derived apoTf acts to inhibit significantly the inflammatory Y-27632 2HCl pathways leading to diabetes. The affected pathways included cytokine-induced beta cell death in
vitro and disease onset in well-established models. In particular, apoTf was associated with milder signs of insulitis and profound modulation of cytokine secretory profile in NOD mice. Several findings may prove significant in our understanding of type 1 diabetes pathogenesis and the role of apoTf. First, the prolonged ex-vivo treatment with apoTf leads to down-modulation of the destructive Th1 and Th17 autoimmune responses [17,21,22] that produce IL-1β, IL-2, TNF-α, IFN-γ, IL-17 and IL-18 [23], which are crucial to diabetes development in the NOD mouse. Th1, Th17 and Treg are thought to be regulated reciprocally and, therefore, changes in Treg could be expected in the immune modulating activity we observed during apoTf treatment in NOD mice [24]. Nevertheless, we could not observe significant changes in the prevalence of Treg (CD4+/CD25+/FoxP3+) cells in the spleen of animals treated for 12 weeks. Further studies are being carried out to demonstrate whether ApoTf exerts its anti-diabetogenic effect by up-regulating Treg function without modifying their numbers or whether it acts via Treg-independent pathways.