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Rechtsmedizin : Organ der Deutschen Gesellschaft für Rechtsmedizin 31(5), 457-462 (2021). doi:10.1007/s00194-021-00460-1 special issue: "COVID-19", Published by Springer, Berlin ; Heidelberg

Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft 117(12), 1229-1233 (2020). doi:10.1007/s00347-020-01077-7 special issue: "Mikrochirurgische Operationstechniken aus ophthalmopathologischer Sicht", Published by Springer, Berlin

Myocardial necrosis triggers inflammatory changes and a complex cytokine cascade that are only incompletely understood. The chemokine receptor CCR1 mediates inflammatory recruitment in response to several ligands released by activated platelets and up-regulated after myocardial infarction (MI). Here, we assess the effect of CCR1 on remodelling after MI using Ccr1-deficient (Ccr1(-)(/-)) mice. MI was induced in Ccr1(-/-) or wild-type mice by proximal ligation of the left anterior descending (LAD). Mice were sacrificed and analysed at day 1, 4, 7, 14 and 21 after MI. While initial infarct areas and areas at risk did not differ between groups, infarct size increased to 20.6+/-8.4% of the left ventricle (LV) in wild-type mice by day 21 but remained at 11.2+/-1.2% of LV (P

Objective— Although junctional adhesion molecule (JAM)-C has been implicated in the control of inflammatory leukocyte recruitment, its role in neointima formation after arterial injury has not been elucidated. Methods and Results— In apolipoprotein E–deficient ( Apoe −/− ) mice fed an atherogenic diet, antibody blockade of JAM-C significantly reduced neointimal hyperplasia after wire injury of carotid arteries without altering medial area and decreased neointimal macrophage but not smooth muscle cell (SMC) content. An increased expression of JAM-C was detected in colocalization with luminal SMCs 1 day after injury and neointimal SMCs after 3 weeks. Blocking JAM-C inhibited monocytic cell arrest and leukocyte adhesion to carotid arteries perfused ex vivo and in vivo. Furthermore, monocyte adhesion to activated coronary artery SMCs under flow conditions in vitro was diminished by blocking JAM-C. Conclusions— Our data provide the first evidence for a crucial role of JAM-C in accelerated lesion formation and leukocyte recruitment in atherosclerosis-prone mice.

Background—Although activation of the complement system has been implicated in the progression of human atherosclerosis, its function during arterial remodeling after injury has not been investigated. Here, we examined the contribution of the complement cascade to neointima formation in apolipoprotein E–deficient mice using a C1-esterase inhibitor (C1-inhibitor).Methods and Results—Apolipoprotein E–deficient mice fed an atherogenic diet were subjected to wire-induced endothelial denudation of the carotid artery and treated with C1-inhibitor (Berinert; 15 IU IV) or vehicle perioperatively and subsequently every 2 days. The effectiveness of C1-inhibitor treatment was confirmed by measurement of plasma C1-inhibitor activity. A significant reduction in serum triglyceride levels was observed in C1-inhibitor–treated mice, whereas cholesterol levels did not differ. After 3 weeks, neointimal area was significantly reduced in C1-inhibitor–treated mice versus controls, whereas medial area was unaltered. This was associated with a significant decrease in neointimal and medial macrophage and CD3+T-cell content. Expression of C3 mRNA was significantly reduced in plaques of C1-inhibitor–treated mice 10 days after injury, as assessed by reverse-transcription polymerase chain reaction. The peak in serum C3 levels after injury was markedly downregulated by C1-inhibitor, as evidenced by ELISA. Immunohistochemistry revealed strong expression of C3 and C3c, which colocalized to plaque macrophages and was reduced in C1-inhibitor–treated mice. C1-inhibitor impaired monocyte arrest on activated endothelium and platelets under flow conditions in vitro and leukocyte recruitment to carotid arteries 1 day after injury in vivo.Conclusions—C1-inhibitor limits neointimal plaque formation and inflammation. This may involve blockade of complement activation, inhibition of leukocyte recruitment, and reduced triglyceride levels, thus providing a multimodal approach to treat arterial disease.

A 62-year-old man presented with mild left hemiparesis, headache, and blurred vision of his right eye. Ten days before, he had undergone thromboendarterectomy because of subtotal stenosis of his right internal carotid artery. MRI revealed confluent white matter edema together with focal hemorrhage consistent with cerebral hyperperfusion syndrome (CHS; figure 1). Likewise, funduscopy showed small retinal hemorrhages confined to the right eye (figure 2). Under careful blood pressure control, symptoms and brain edema fully resolved within weeks. CHS occurs in around 3% of patients undergoing carotid thromboendarterectomy and can induce severe neurologic deficits.1 Rarely, hyperperfusion also involves the ipsilateral eye.2