Indocyanine green-based adjunctive antimicrobial photodynamic therapy for treating chronic periodontitis: A randomized clinical trial.

BACKGROUND: The objective was to evaluate the efficiency of indocyanine green (ICG)-based adjunctive antimicrobial photodynamic therapy (aPDT) in a prospective clinical study regarding non-surgical treatment of chronic periodontitis. METHODS: Affected teeth of twenty patients were treated with scaling and root planing (control group). Using a split-mouth design, two quadrants received additional ICG-based (perio green®, 0.1 mg/ml) aPDT (test group) with a diode laser at 808 nm (100 mW at 2 kHz). Clinical assessment of bleeding on probing (BOP), sulcus fluid flow rate (SFFR) and microbiological analysis were performed at baseline, two weeks, three and six months after treatment. Relative attachment level (RAL), probing depths (PD) and gingival recession (GR), were also analyzed. RESULTS: At baseline, none of the assessed parameters showed significant differences between the test and control groups. Median values for BOP, RAL, PD, decreased significantly in both groups after three months of treatment (p ≤ 0.05) without significant difference between the groups. Two weeks after treatment, the SFFR showed significantly lower mean values in the test group (aPDT). CONCLUSION: Within the study limits, the only significant difference between the control group and the aPDT group was a transient smaller amount of SFFR in the latter during the first follow-up. With the applied parameters, this study does not conclusively support ICG-based aPDT, though it is promising because no adverse effects occurred. The precise modes of action of ICG must be elucidated, and further clinical trials are needed.

Immune- and miRNA-response to recombinant interferon beta-1a: a biomarker evaluation study to guide the development of novel type I interferon- based therapies.

BACKGROUND: The innate immune receptor RIG-I detects viral RNA within the cytosol of infected cells. Activation of RIG-I leads to the induction of antiviral cytokines, in particular type I interferon, the inhibition of a T(H)17 response as well as to the suppression of tumor growth. Therefore, RIG-I is a promising drug target for the treatment of cancer as well as multiple sclerosis. A specific ligand for RIG-I is currently in preclinical testing. The first-in-human trial will need to be carefully designed to avoid an overshooting cytokine response. Therefore, the ResI study was set up to analyze the human immune response to standard treatment with recombinant interferon-beta to establish biomarkers for safety and efficacy of the upcoming first-in-human trial investigating the RIG-I ligand. METHODS/DESIGN: ResI is a single center, prospective, open label, non-randomized phase I clinical trial. Three different cohorts (20 healthy volunteers, 20 patients with RRMS and ongoing interferon-beta treatment and 10 patients starting on interferon-beta) will receive standard interferon-beta-1a therapy for nine days. The study will be conducted according to the principles of the german medicinal products act, ICH-GCP, and the Declaration of Helsinki on the phase I unit of the Institute of Clinical Chemistry and Clinical Pharmacology and in the Department of Neurology, both University Hospital Bonn. Interferon-beta-induced cytokine levels, surface marker on immune cells, mRNA- and miRNA-expression as well as psychometric response will be investigated as target variables. DISCUSSION: The ResI study will assess biomarkers in response to interferon-ß treatment to guide the dose steps within the first-in-human trial with a newly developed RIG-I ligand. Thus, ResI is a biomarker study to enhance the safety of the clinical development of a first-in-class compound. The data can additionally be used for the development of other therapies based on type I interferon induction such as TLR ligands. Moreover, it will help to understand the interferon-beta induced immune response in a controlled in vivo setting in the human system. TRIAL REGISTRATION: clinicaltrials.gov ID NCT02364986.

P2X1 receptor-mediated inhibition of the proliferation of human coronary smooth muscle cells involving the transcription factor NR4A1.

Adenine nucleotides acting at P2X1 receptors are potent vasoconstrictors. Recently, we demonstrated that activation of adenosine A2B receptors on human coronary smooth muscle cells inhibits cell proliferation by the induction of the nuclear receptor subfamily 4, group A, member 1 (NR4A1; alternative notation Nur77). In the present study, we searched for long-term effects mediated by P2X1 receptors by analyzing receptor-mediated changes in cell proliferation and in the expression of NR4A1. Cultured human coronary smooth muscle cells were treated with selective receptor ligands. Effects on proliferation were determined by counting cells and measuring changes in impedance. The induction of transcription factors was assessed by qPCR. The P2X receptor agonist α,ß-methylene-ATP and its analog ß,γ-methylene-ATP inhibited cell proliferation by about 50 % after 5 days in culture with half-maximal concentrations of 0.3 and 0.08 µM, respectively. The effects were abolished or markedly attenuated by the P2X1 receptor antagonist NF449 (carbonylbis-imino-benzene-triylbis-(carbonylimino)tetrakis-benzene-1,3-disulfonic acid; 100 nM and 1 µM). α,ß-methylene-ATP and ß,γ-methylene-ATP applied for 30 min to 4 h increased the expression of NR4A1; NF449 blocked or attenuated this effect. Small interfering RNA directed against NR4A1 diminished the antiproliferative effects of α,ß-methylene-ATP and ß,γ-methylene-ATP. α,ß-methylene-ATP (0.1 to 30 µM) decreased migration of cultured human coronary smooth muscle cells in a chamber measuring changes in impedance; NF449 blocked the effect. In conclusion, our results demonstrate for the first time that adenine nucleotides acting at P2X1 receptors inhibit the proliferation of human coronary smooth muscle cells via the induction of the early gene NR4A1.

A2B receptors mediate the induction of early genes and inhibition of arterial smooth muscle cell proliferation via Epac.

AIMS: Extracellular adenosine and adenine nucleotides play important roles in the regulation of the blood vessel tonus and platelet aggregation. Less is known about the effects of these extracellular signalling molecules on gene expression in vascular smooth muscle cells involved in long-term vascular effects. In the present study, we therefore searched for adenosine-induced changes in the expression of early genes in cultured human coronary artery smooth muscle cells (HCASMCs). METHODS AND RESULTS: Whole-genome DNA array hybridization revealed that adenosine induced a set of early genes including the nuclear receptor subfamily 4, group A, member 1 (NR4A1/Nur77/TR3). The pattern of the effects of adenosine on gene expression resembles the change in expression induced by the direct activator of adenylate cyclase forskolin. Real-time reverse-transcriptase PCR confirmed that adenosine and its analogue N-ethyl-carboxamidoadenosine elicited a strong induction of NR4A1. These effects were markedly attenuated by A(2B) receptor antagonists including 8-[4-(4-benzylpiperazide-1-sulfonyl)phenyl]-1-propylxanthine (PSB-601) and were mimicked by a cyclic AMP (cAMP) analogue [8-(4-chlorophenylthio)-2'-O-methyl-cAMP, 8CPT] acting on the exchange protein activated by cAMP (Epac). Long-term experiments over 5 days showed that 2-chloroadenosine decreased cell proliferation in the presence of platelet-derived growth factor. This effect of 2-chloroadenosine was also attenuated by PSB-601 and mimicked by 8CPT. Treatment with small interfering RNA directed against NR4A1 attenuated the inhibitory effect of 8CPT on proliferation. CONCLUSIONS: In summary, our results demonstrate the operation of adenosine A2(B) receptors mediating an early induction of NR4A1 and a decrease in cell proliferation via the cAMP/Epac pathway in HCASMCs.