Safety, pharmacokinetics, and preliminary efficacy of a specific anti-IL-1alpha therapeutic antibody (MABp1) in patients with type 2 diabetes mellitus

AIMS

The role of the IL-1 system in development of type 2 diabetes is well established. Using an IL-1 receptor antagonist, which blocks IL-1alpha and -beta activity, or by specifically neutralizing IL-1beta, several clinical studies have demonstrated improvement in insulin secretion and glycaemia. However, the role of IL-1alpha remains to be investigated.

METHODS

We evaluated the safety and preliminary efficacy of a neutralizing true human™ monoclonal antibody against IL-1alpha (MABp1) in an open label trial in patients with type 2 diabetes. Seven patients between 50 to 66years with type 2 diabetes mellitus were enrolled in the study. The study subjects received four biweekly intravenous infusions of MABp1 at 1.25mg/kg body weight up to day 60 and were followed up for a total of 90days.

RESULTS

Compared to baseline, after the 60-day period of treatment HbA1c was numerically reduced by 0.14±0.21% (p=0.15), fasting C-peptide was increased by 88% (p=0.03), pro-insulin by 48% (p=0.03) and insulin numerically increased by 74% (p=0.11). Systolic blood pressure numerically decreased by 11mmHg (p=0.2). Both HbA1c and blood pressure rebounded to baseline levels thirty days after the end of MABp1 application. Treatment with MABp1 was well tolerated, and no adverse events occurred during the study.

CONCLUSION

The results point to a role of IL-1alpha in type 2 diabetes and encourage further investigations. (ClinicalTrials.gov number NCT01427699).

Involvement of endogenous transforming growth factor-α in signal transduction pathway for interleukin-1β-induced hepatocyte proliferation

We studied the effects of interleukin (IL)-1β on DNA synthesis and cell proliferation in primary cultures of adult rat hepatocytes in order to elucidate the mechanisms of its action. Hepatocyte parenchymal cells maintained in a serum-free, defined medium synthesized DNA and proliferated in the presence of IL-1β (3-30 ng/ml), but not IL-1α (0.1-30 ng/ml) in a time- and dose-dependent manner. Specific inhibitors of growth-related signal transducers, such as AG1478, LY294002, PD98059, and rapamycin, completely abolished IL-1β-stimulated hepatocyte DNA synthesis and proliferation. Western blot analysis showed that IL-1β significantly stimulated mitogen-activated protein (MAP) kinase activation within 10 min. Addition of a monoclonal antibody against transforming growth factor (TGF)-α, but not a monoclonal antibody against insulin-like growth factor-I, to the culture dose-dependently inhibited IL-1β-induced hepatocyte mitogenesis. Culture medium TGF-α levels increased significantly within 3 min in response to IL-1β from baseline levels. Peak TGF-α levels (33 pg/ml) were reached at 10 min after IL-1β stimulation. These results indicate that the proliferative mechanism of action of IL-1β is mediated through an increase in autocrine secretion of TGF-α from primary cultured hepatocytes. Secreted TGF-α, in turn, acts as a complete mitogen to induce hepatocyte mitogenesis through the receptor tyrosine kinase/phosphatidylinositol 3-kinase/MAP kinase/mammalian target of rapamycin pathway.

IL-1 signalling is dispensable for protective immunity in Leishmania-resistant mice

Leishmaniasis is a parasitic disease affecting ∼12 million people. Control of infection (e.g. in C57BL/6 mice) results from IL-12-dependent production of IFNγ by Th1/Tc1 cells. In contrast, BALB/c mice succumb to infection because of preferential Th2-type cytokine induction. Infected dendritic cells (DC) represent important sources of IL-12. Genetically determined differences in DC IL-1α/β production contribute to disease outcome. Whereas the course of disease was not dramatically altered in IL-1RI(-/-) mice, local administration of IL-1α to infected C57BL/6 mice improved disease outcome. To definitively elucidate the involvement of IL-1 in immunity against leishmaniasis, we now utilized IL-1α/β-double-deficient C57BL/6 mice. C57BL/6 mice are believed to be a good surrogate model for human, self limited cutaneous leishmaniasis (CL). Leishmania major-infected IL-1α/β(-/-) mice were resistant to experimental CL comparable to controls. In addition, DC-based vaccination against leishmaniasis in C57BL/6 mice was independent of IL-1. Thus, in Leishmania-resistant C57BL/6 mice, IL-1 signalling is dispensable for protection.

Roles for IL-1 and TNFalpha in dynamic behavioral responses of Langerhans cells to topical hapten application

BACKGROUND

To understand the behavioral biology of Langerhans cells (LCs), we recently recorded time-lapse images of LCs in the knock-in mice expressing the I-Abeta chain tagged with the enhanced green fluorescence protein (EGFP). EGFP(+) LCs showed relatively limited motility in the steady state, whereas topical application of dinitrofluorobenzene (DNFB) markedly augmented a unique movement of dendrites characterized by rhythmic extension and retraction, termed dSEARCH, and triggered amoeba-like lateral migration of cell bodies.

OBJECTIVE

To define underlying mechanisms by which hapten treatment alters LC behaviors.

METHODS

The I-Abeta-EGFP mice received subcutaneous (s.c.) injection of recombinant IL-1alpha or TNFalpha (50 ng/animal) and dynamic behaviors of EGFP(+) LCs were recorded by time-lapse confocal microscopy at several time points to measure their dSEARCH activities and lateral migration. In a different set of experiments, IL-1 receptor antagonist (IL-1Ra) or soluble TNF receptor-2 (sTNFR2) (0.5 microg/animal) was s.c. injected into the ear skin 30 min before topical application of DNFB, and LC behaviors analyzed 30 h later.

RESULTS

Local injection of IL-1alpha or TNFalpha induced significant, albeit modest, augmentation of both dSEARCH and lateral migration. Co-injection of TNFalpha and IL-1alpha further exacerbated motile activities in a synergistic manner by similar magnitudes observed after DNFB application. Conversely, DNFB-induced behavioral changes were inhibited completely by local injection of IL-1Ra or sTNFR2.

CONCLUSION

IL-1 and TNFalpha serve as equally important mediators of hapten-induced alteration of LC behaviors. Motile activities of epidermal LCs are reprogrammed by selected cytokines known to be produced by keratinocytes under pathological conditions.

IL-1 alpha causes lung inflammation and maturation by direct effects on preterm fetal lamb lungs

Intra-amniotic endotoxin induces IL-1, causes chorioamnionitis, lung inflammation, lung injury and lung maturation in preterm lambs. Intra-amniotic IL-1alpha also causes chorioamnionitis, lung inflammation and lung maturation. We asked if IL-1alpha effects on the preterm lung are mediated by direct signaling to the lung rather than by indirect effects from the chorioamnionitis. To study IL-1 effects independently of chorioamnionitis, the lungs and the amniotic fluid were surgically separated in fetal sheep by diverting fetal lung fluid via a tracheostomy tube to a sialastic bag. A mini-osmotic pump delivered an intratracheal infusion of recombinant sheep IL-1alpha (10 microg) or saline (control) over 24 h. Preterm lambs were delivered 1d or 7d after the start of the infusion at 124d gestational age (Term = 150d). IL-1alpha recruited inflammatory cells and increased pro-inflammatory cytokine mRNA expression in the fetal lungs. Compared with controls, IL-1alpha did not alter lung antioxidant enzyme activity or alveolar numbers. IL-1alpha had minimal effects on the mRNA or protein expression of proteins essential for vascular development. IL-1alpha induced large increases in alveolar surfactant saturated phosphatidylcholine and increased lung gas volumes. Lung inflammation and maturation result from direct exposure of the fetal lung to a single cytokine - IL-1alpha.