Effective treatment for managing myocardial infarction (MI) remains an urgent, unmet clinical need. Formyl peptide receptors (FPR) regulate inflammation, a major contributing mechanism to cardiac injury following MI. Here we demonstrate that FPR1/FPR2-biased agonism may represent a novel therapeutic strategy for the treatment of MI. The small-molecule FPR1/FPR2 agonist, Compound 17b (Cmpd17b), exhibits a distinct signalling fingerprint to the conventional FPR1/FPR2 agonist, Compound-43 (Cmpd43). In Chinese hamster ovary (CHO) cells stably transfected with human FPR1 or FPR2, Compd17b is biased away from potentially detrimental FPR1/2-mediated calcium mobilization, but retains the pro-survival signalling, ERK1/2 and Akt phosphorylation, relative to Compd43. The pathological importance of the biased agonism of Cmpd17b is demonstrable as superior cardioprotection in both in vitro (cardiomyocytes and cardiofibroblasts) and MI injury in mice in vivo. These findings reveal new insights for development of small molecule FPR agonists with an improved cardioprotective profile for treating MI.

The anti-inflammatory, pro-resolving annexin-A1 protein acts as an endogenous brake against exaggerated cardiac necrosis, inflammation, and fibrosis following myocardial infarction (MI) in vivo . Little is known, however, regarding the cardioprotective actions of the N-terminal-derived peptide of annexin A1, Ac 2-26 , particularly beyond its anti-necrotic actions in the first few hours after an ischemic insult. In this study, we tested the hypothesis that exogenous Ac 2-26 limits cardiac injury in vitro and in vivo. Firstly, we demonstrated that Ac 2-26 limits cardiomyocyte death both in vitro and in mice subjected to ischemia-reperfusion (I-R) injury in vivo (Ac 2-26, 1 mg/kg, i.v. just prior to post-ischemic reperfusion). Further, Ac 2-26 (1 mg/kg i.v.) reduced cardiac inflammation (after 48 h reperfusion), as well as both cardiac fibrosis and apoptosis (after 7-days reperfusion). Lastly, we investigated whether Ac 2-26 preserved cardiac function after MI. Ac 2-26 (1 mg/kg/day s.c., osmotic pump) delayed early cardiac dysfunction 1 week post MI, but elicited no further improvement 4 weeks after MI. Taken together, our data demonstrate the first evidence that Ac 2-26 not only preserves cardiomyocyte survival in vitro , but also offers cardioprotection beyond the first few hours after an ischemic insult in vivo . Annexin-A1 mimetics thus represent a potential new therapy to improve cardiac outcomes after MI.

To investigate the influence of fractionation on cell survival and radiation induced premature differentiation as markers for early and late effects after X-rays and carbon irradiation. Normal human fibroblasts NHDF, AG1522B and WI-38 were irradiated with 250 kV X-rays, or 266 MeV/u, 195 MeV/u and 11 MeV/u carbon ions. Cytotoxicity was measured by a clonogenic survival assay or by determination of the differentiation pattern. Experiments with high-energy carbon ions show that fractionation induced repair effects are similar to photon irradiation. The RBE(10) values for clonogenic survival are 1.3 and 1.6 for irradiation in one or two fractions for NHDF cells and around 1.2 for AG1522B cells regardless of the fractionation scheme. The RBE for a doubling of post mitotic fibroblasts (PMF) in the population is 1 for both single and two fractionated irradiation of NHDF cells. Using 11 MeV/u carbon ions, no repair effect can be seen in WI-38 cells. The RBE(10) for clonogenic survival is 3.2 for single irradiation and 4.9 for two fractionated irradiations. The RBE for a doubling of PMF is 3.1 and 5.0 for single and two fractionated irradiations, respectively. For both cell lines the effects of high-energy carbon ions representing the irradiation of the skin and the normal tissue in the entrance channel are similar to the effects of X-rays. The fractionation effects are maintained. For the lower energy, which is representative for the irradiation of the tumor region, RBE is enhanced for clonogenic survival as well as for premature terminal differentiation. Fractionation effects are not detectable. Consequently, the therapeutic ratio is significantly enhanced by fractionated irradiation with carbon ions.

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Background Natural killer (NK) cells typically function as frontline lymphocytes against cancer although little is known about their engagement in non–small cell lung cancer (NSCLC). This study compared the performance and activity of NK cells and their subsets in the peripheral blood of NSCLC sufferers and healthy participants. Methods In total, 67 healthy controls (40 men; 59.7%) and 56 patients with NSCLC (35 men; 62.5%) were included (mean age, 66.6 years). Flow cytometry identified NK cells and their subpopulations in external blood, and the total number, proportion, activity, surface activating and inhibitory receptor expression levels were determined. Results NK cell surface receptors CD107a, IFN-γ, and TNF-α activity were markedly reduced in lung cancer patients compared to healthy controls. The number and ratio of NK cells within the lymphocyte population were decreased in patients. The concentration of the inhibitory receptors TIGIT, TIM-3, CD96, PD-1, and Siglec-7 were increased in patients, whereas the expression level of the activating receptor NKP30 was decreased. Moreover, the expression levels of IFN-γ, TIGIT, CD96, PD-1, and TIM-3 were correlated with the clinical phase of NSCLC.Conclusions NSCLC patients have decreased number and function of external blood NK cells, and the proportion of most of the inhibitory receptors assessed on NK cells in this study increased as the disease progressed. These findings suggest that surface receptors from NK cells are likely to be involved in the evolution of NSCLC.

Myocardial infarction (MI) is the major cause of heart failure and death in the Western world. Annexin-A1 is an endogenous, glucocorticoid-regulated anti-inflammatory protein. We have previously shown that this protein plays an important protective role in preserving left ventricular (LV) viability and function in vitro, actions that are reproduced by treatment with its N-terminal-derived peptide, Ac2-26. Little is known however about its cardioprotective actions in vivo, particularly beyond its early anti-necrotic actions in the first few hours of reperfusion. We now test the hypothesis that exogenous Ac2-26 limits multiple aspects of MI injury, over both the short and longer-term in vivo. In the first study, adult C57BL/6 mice were subjected to ischemia-reperfusion (left arterial descending coronary artery ligation, with 1-7 days reperfusion), and Ac2-26 was administered at 1mg/kg i.v. every 24h commencing 5mins before reperfusion. In the second study, mice were subjected to permanent coronary artery occlusion, with Ac2-26 administered 1mg/kg/day i.p. via osmotic pump inserted at time of surgery. As shown in the Table, Ac2-26 reduced cardiac necrosis after 24h reperfusion (infarct size, plasma troponin I levels), systemic and cardiac inflammation after 48h reperfusion (neutrophil and macrophage infiltration) and cardiac fibrosis after 7 days reperfusion. These protective actions at the level of cardiac morphology were associated with preservation of LV function 4wks after permanent occlusion, as determined on fractional shortening and velocity of circumferential fiber shortening. Taken together, our data is the first evidence of Ac2-26 cardioprotection beyond the first few hours of reperfusion in vivo, and importantly, the first to report Ac2-26-induced preservation of LV function in the heart post MI in vivo.