Neutrophils Induced Licensing of Natural Killer Cells

application/pdfNatural killer (NK) cells acquire effector function through a licensing process and exert anti-leukemia/tumor effect. However, there is no means to promote a licensing effect of allogeneic NK cells other than cytomegalovirus reactivation-induced licensing in allogeneic hematopoietic stem cell transplantation in human. In mice, a licensing process is mediated by Ly49 receptors which recognize self-major histocompatibility complex class I. The distribution of four Ly49 receptors showed similar pattern in congenic mice, B10, B10.BR, and B10.D2, which have B10 background. Forty Gy-irradiated 2 × 106 B10. D2 cells including splenocytes, peripheral blood mononuclear cells in untreated mice, or granulocyte colony-stimulating factor treated mice were injected intraperitoneally into B10 mice. We found that murine NK cells were effectively licensed by intraperitoneal injection of donor neutrophils with its corresponding NK receptor ligand in B10 mice as a recipient and B10. D2 as a donor. Mechanistic studies revealed that NK cells showed the upregulation of intracellular interferon-γ and CD107a expression as markers of NK cell activation. Moreover, enriched neutrophils enhanced licensing effect of NK cells; meanwhile, licensing effect was diminished by depletion of neutrophils. Collectively, injection of neutrophils induced NK cell licensing (activation) via NK receptor ligand interaction.本文/Department of Pediatrics, Mie University Graduate School of Medicine9

Neutrophils Induced Licensing of Natural Killer Cells

application/pdf内容の要旨・審査結果の要旨 / 三重大学大学院医学系研究科 生命医科学専攻 病態解明医学講座小児発達医学分

Neutrophils Induced Licensing of Natural Killer Cells

Natural killer (NK) cells acquire effector function through a licensing process and exert anti-leukemia/tumor effect. However, there is no means to promote a licensing effect of allogeneic NK cells other than cytomegalovirus reactivation-induced licensing in allogeneic hematopoietic stem cell transplantation in human. In mice, a licensing process is mediated by Ly49 receptors which recognize self-major histocompatibility complex class I. The distribution of four Ly49 receptors showed similar pattern in congenic mice, B10, B10.BR, and B10.D2, which have B10 background. Forty Gy-irradiated 2×106 B10.D2 cells including splenocytes, peripheral blood mononuclear cells in untreated mice, or granulocyte colony-stimulating factor treated mice were injected intraperitoneally into B10 mice. We found that murine NK cells were effectively licensed by intraperitoneal injection of donor neutrophils with its corresponding NK receptor ligand in B10 mice as a recipient and B10.D2 as a donor. Mechanistic studies revealed that NK cells showed the upregulation of intracellular interferon-γ and CD107a expression as markers of NK cell activation. Moreover, enriched neutrophils enhanced licensing effect of NK cells; meanwhile, licensing effect was diminished by depletion of neutrophils. Collectively, injection of neutrophils induced NK cell licensing (activation) via NK receptor ligand interaction

Extraction of a metallic susceptor after accidental ingestion of the heated tobaccostick TEREA™: a case report

Abstract Background Tobacco ingestion is widely known to cause nicotine toxicity, which may result in severe symptoms. Two heated tobacco sticks, called TEREA™ and SENTIA™, were launched in 2021 by Philip Morris International (New York, NY, USA), and their ingestion is associated with a risk of bowel injury because they contain a partially pointed metallic susceptor. However, this risk is not well known to the general public or healthcare providers. To increase awareness of this risk, we herein report a case involving extraction of a metallic susceptor after ingestion of the heated tobacco stick TEREA™. Case presentation A 7-month-old girl presented to the emergency department of a nearby hospital because she was suspected to have accidentally swallowed heated tobacco. Although she presented with no symptoms related to nicotine poisoning, abdominal X-ray examination revealed a metal object in her stomach. According to a statement released by the Japan Poison Information Center, the TEREA™ heated tobacco stick contains a metallic susceptor with a rectangular shape and sharp corners. The patient was transferred to our department because of the risk of bowel injury, and upper gastrointestinal endoscopy was performed. No cigarettes were found by endoscopic observation; however, a metallic susceptor was located in the second part of the duodenum. We grasped it with biopsy forceps and carefully removed it using an endoscope with a cap attached to the tip. The post-endoscopic course was uneventful. Conclusions Some patients who ingest heated tobacco sticks might be exposed not only to the effects of nicotine but also to physical damage caused by a metallic susceptor. Infants and toddlers especially could swallow these sticks, therefore tobacco companies need to make the problem more public. Clinicians also should alert the problem, and pay attention to this risk in the clinical setting