Extracellular CIRP promotes Kupffer cell inflammatory polarization in sepsis.

Introduction: Sepsis is a life-threatening inflammatory condition caused by dysregulated host responses to infection. Extracellular cold-inducible RNA-binding protein (eCIRP) is a recently discovered damage-associated molecular pattern that causes inflammation and organ injury in sepsis. Kupffer cells can be activated and polarized to the inflammatory M1 phenotype, contributing to tissue damage by producing proinflammatory mediators. We hypothesized that eCIRP promotes Kupffer cell M1 polarization in sepsis. Methods: We stimulated Kupffer cells isolated from wild-type (WT) and TLR4-/- mice with recombinant mouse (rm) CIRP (i.e., eCIRP) and assessed supernatant IL-6 and TNFα levels by ELISA. The mRNA expression of iNOS and CD206 for M1 and M2 markers, respectively, was assessed by qPCR. We induced sepsis in WT and CIRP-/- mice by cecal ligation and puncture (CLP) and assessed iNOS and CD206 expression in Kupffer cells by flow cytometry. Results: eCIRP dose- and time-dependently increased IL-6 and TNFα release from WT Kupffer cells. In TLR4-/- Kupffer cells, their increase after eCIRP stimulation was prevented. eCIRP significantly increased iNOS gene expression, while it did not alter CD206 expression in WT Kupffer cells. In TLR4-/- Kupffer cells, however, iNOS expression was significantly decreased compared with WT Kupffer cells after eCIRP stimulation. iNOS expression in Kupffer cells was significantly increased at 20 h after CLP in WT mice. In contrast, Kupffer cell iNOS expression in CIRP-/- mice was significantly decreased compared with WT mice after CLP. CD206 expression in Kupffer cells was not different across all groups. Kupffer cell M1/M2 ratio was significantly increased in WT septic mice, while it was significantly decreased in CIRP-/- mice compared to WT mice after CLP. Conclusion: Our data have clearly shown that eCIRP induces Kupffer cell M1 polarization via TLR4 pathway in sepsis, resulting in overproduction of inflammatory cytokines. eCIRP could be a promising therapeutic target to attenuate inflammation by preventing Kupffer cell M1 polarization in sepsis.

EXTRACELLULAR CIRP INHIBITS NEUTROPHIL APOPTOSIS TO PROMOTE ITS AGING BY UPREGULATING SERPINB2 IN SEPSIS.

ABSTRACT: Background: Sepsis reduces neutrophil apoptosis. As the result, neutrophils may become aged, exacerbating inflammation and tissue injury. Extracellular cold-inducible RNA-binding protein (eCIRP) acts as a damage-associated molecular pattern to promote inflammation and tissue injury in sepsis. SerpinB2, a serine protease inhibitor, has been shown to inhibit apoptosis. We hypothesize that eCIRP upregulates SerpinB2 to promote aged neutrophil subset by inhibiting apoptosis in sepsis. Methods: We stimulated bone marrow-derived neutrophils (BMDNs) of wild-type (WT) mice with 1 µg/mL of recombinant mouse CIRP (i.e., eCIRP) and assessed cleaved caspase-3 and SerpinB2 by western blotting. Apoptotic neutrophils were assessed by Annexin V/PI. Bone marrow-derived neutrophils were stimulated with 1 µg/mL eCIRP and treated with or without PAC-1 (caspase-3 activator) and aged neutrophils (CXCR4 hi CD62L lo ) were assessed by flow cytometry. To induce sepsis, we performed cecal ligation and puncture in WT or CIRP -/- mice. We determined the percentage of aged neutrophils and SerpinB2 + neutrophils in blood and spleen by flow cytometry. Results: We found that cleaved caspase-3 levels were increased at 4 h of PBS treatment compared with 0 h but decreased by eCIRP treatment. Extracellular cold-inducible RNA-binding protein reduced apoptotic cells after 20 h of treatment. Extracellular cold-inducible RNA-binding protein also increased the frequencies of aged neutrophils compared with PBS after 20 h, while PAC-1 treatment reduced aging in eCIRP-treated BMDNs. Extracellular cold-inducible RNA-binding protein significantly increased the expression of SerpinB2 at protein levels in BMDNs at 20 h. In WT mice, the frequencies of aged and SerpinB2 + neutrophils in blood and spleen were increased after 20 h of cecal ligation and puncture, while in CIRP -/- mice, aged and SerpinB2 + neutrophils were significantly decreased compared with WT mice. We also found that aged neutrophils expressed significantly higher levels of SerpinB2 compared with non-aged neutrophils. Conclusions: eCIRP inhibits neutrophil apoptosis to increase aged phenotype by increasing SerpinB2 expression in sepsis. Thus, targeting eCIRP could be a new therapeutic strategy to ameliorate inflammation caused by neutrophil aging in sepsis.

Extracellular CIRP Promotes GPX4-Mediated Ferroptosis in Sepsis.

Sepsis is characterized by life-threatening organ dysfunction caused by a dysregulated host response to infection. Extracellular cold-inducible RNA-binding protein (eCIRP) is a damage-associated molecular pattern (DAMP) that promotes inflammation and induces cell death via apoptosis, NETosis, and/or pyroptosis. Ferroptosis is a form of regulated cell death characterized by the accumulation of lipid peroxide on cellular membranes. We hypothesize that eCIRP induces ferroptosis in macrophages and lung tissue during sepsis. RAW 264.7 cells stimulated with recombinant murine (rm) CIRP significantly decreased the expression of glutathione peroxidase 4 (GPX4), a negative regulator of ferroptosis, and increased lipid reactive oxygen species (ROS) in a TLR4 dependent manner. In TLR4-/- peritoneal macrophages, depression of GPX4 expression and increase in lipid ROS levels were attenuated after rmCIRP-treatment compared to WT macrophages. rmCIRP also induced cell death in RAW 264.7 cells which was corrected by the ferroptosis inhibitor, ferrostatin-1 (Fer-1). Intraperitoneal injection of rmCIRP decreased GPX4 expression and increased lipid ROS in lung tissue, whereas the increase of lipid ROS was reduced by Fer-1 treatment. GPX4 expression was significantly decreased, while malondialdehyde (MDA), iron levels, and injury scores were significantly increased in lungs of WT mice after cecal ligation and puncture (CLP)-induced sepsis compared to CIRP-/- mice. Treatment with C23, a specific eCIRP inhibitor, in CLP mice alleviated the decrease in GPX4 and increase in MDA levels of lung tissue. These findings suggest that eCIRP induces ferroptosis in septic lungs by decreasing GPX4 and increasing lipid ROS. Therefore, regulation of ferroptosis by targeting eCIRP may provide a new therapeutic approach in sepsis and other inflammatory diseases.

Association between plasma complement factor H concentration and clinical outcomes in patients with sepsis.

AIM: The complement system is important for defending against pathogens, however, excessive complement activation is associated with a poor prognosis and organ dysfunction in sepsis. Complement factor H (CFH) acts to prevent excessive complement activation and damage to the self through the regulation of the complement alternative pathway. We investigated the association between plasma CFH levels on admission to the intensive care unit (ICU) and 90-day mortality, severity scores, and organ dysfunction in patients with sepsis. METHODS: We assessed the relationship between the plasma CFH on admission to the ICU and 90-day mortality, severity scores such as the Acute Physiology and Chronic Health Evaluation II score, Sequential Organ Failure Assessment score, and Simplified Acute Physiology Score 2, and organ dysfunction. RESULTS: This analysis included 62 patients. The plasma CFH levels were significantly lower in 90-day non-survivors than in survivors (70.0 µg/mL [interquartile range, 51.2-97.6] versus 104.8 µg/mL [interquartile range, 66.8-124.2]; P = 0.006) . The plasma CFH levels were associated with 90-day mortality (odds ratio 0.977; 95% confidence interval, 0.957-0.994; P = 0.01). The plasma CFH levels were negatively correlated with severity scores. The Sequential Organ Failure Assessment scores for the coagulation and neurological components were negatively correlated with the CFH concentration. CONCLUSION: Lower plasma levels of CFH were associated with increased severity and mortality in patients with sepsis on admission to the ICU and were correlated with central nervous system dysfunction and coagulopathy.

Vasovagal Reaction and Ischemic Colitis Following Blood Donation.

Vasovagal reactions are the most common type of adverse reaction after blood donation; however, there are no reports of ischemic colitis as an adverse reaction after blood donation. A previously healthy 55-year-old woman suffered loss of consciousness at the end of her first plasma donation. She was diagnosed with a vasovagal reaction and received hydration. However, she developed persistent left flank pain and watery diarrhea, followed by bloody diarrhea. Abdominal computed tomography confirmed ischemic colitis. She was asked to fast and was eventually discharged 7 days later. We should consider the possibility of ischemic colitis if patients develop persistent abdominal pain after transient hypotension, such as that observed during a vasovagal reaction.

Propofol infusion syndrome complicated with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes: a case report.

BACKGROUND: Propofol infusion syndrome (PRIS) is a rare but lethal complication of propofol use. It has been suggested that the pathological mechanism of PRIS involves mitochondrial disorder caused by propofol. CASE PRESENTATION: A 24-year-old woman who had been diagnosed with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes was admitted to our hospital with impaired consciousness and myoclonus. To control the non-convulsive status epilepticus, propofol was administered. Arterial blood gas revealed metabolic acidosis, and creatinine kinase was elevated. The patient was diagnosed with PRIS. We treated her with interruption of propofol. She required mechanical ventilation for 25 days. After rehabilitation, she recovered and was discharged. CONCLUSION: Mitochondrial disorder is a risk factor for PRIS. It is important for clinicians to be aware that mitochondrial disorder is a risk factor for PRIS, especially under conditions of critical illness and status epilepticus.

Sepsis in a 4-Month-Old Boy Due to Carbapenem-Resistant Enterobacteriaceae Characterized by AmpC ß-Lactamase with Porin Loss.

The incidence of carbapenem-resistant Enterobacteriaceae (CRE) infections is increasing, and these infections are associated with both morbidity and mortality. However, little is known about CRE infections in children. This article is a case report describing a 4-month-old boy with Langerhans histiocytosis who developed septic shock due to a CRE infection. The mechanism of carbapenem resistance was identified as AmpC ß-lactamase hyperproduction with porin loss. The patient was treated with antibiotics, volume resuscitation, and vasopressors; however, he died of multiorgan failure due to CRE infection. Clinicians should be aware of the prevalence of CRE and the importance of prevention strategies against infection with multidrug-resistant bacteria, even in pediatric populations.

Airway obstruction caused by rapid enlargement of cervical lymphangioma in a five-month-old boy.

Cervical lymphangioma can cause airway obstruction secondary to enlargement following infection. Physicians should be aware that the airway obstruction can progress rapidly when patients with cervical lymphangioma have respiratory symptoms. Sclerotherapy for lymphangioma can cause both transient swelling and airway obstruction; thus, prophylactic and elective tracheostomy should be considered.

The first two cases of neonatal alloimmune thrombocytopenia associated with the low-frequency platelet antigen HPA-21bw (Nos) in Japan.

BACKGROUND: Neonatal alloimmune thrombocytopenia (NAIT) is a disorder characterized by maternal alloimmunization against paternal fetal platelet antigens. Two healthy, unrelated Japanese women each gave birth to a child with severe NAIT. STUDY DESIGN AND METHODS: To elucidate the maternal causes of NAIT, we conducted serologic and genetic studies in these two NAIT infants. RESULTS: The serologic experiments localized the antigens to the glycoprotein (GP) IIIa subunit of the GPIIb/IIIa complex. Sequence-based typing studies subsequently identified a G>A mutation at Nucleotide 1960 (a glutamic acid > lysine substitution at Position 628) in the 11th exon of the GPIIIa gene. This mutation was recently identified in a report as HPA-21bw. Next, it was determined that the cause of NAIT in both cases was the HPA-21bw antigen, as shown by the mothers' antibodies reacting with the mutated GPIIIa-transfected cells, but not with transfectants expressing wild-type GPIIIa. A molecular genetic screening for the HPA-21bw allele among Japanese donors showed that its genetic frequency in the population was 0.53% (10/1888), indicating that HPA-21bw occurs at a low but appreciable frequency in the population. Furthermore, in a retrospective study of 50 previous NAIT cases of unknown causes, we found one NAIT case associated with the HPA-21bw antibody. The two NAIT cases in this study represent the first ones to be associated with HPA-21bw in Japan. CONCLUSION: We identified the HPA-21bw allele from two unrelated Japanese infants with severe NAIT. We identified 10 individuals (1.06%) positive for the HPA-21bw allele from a genetic screening of 944 Japanese blood donors.

Spinal glioblastoma multiforme of the conus medullaris with holocordal and intracranial spread in a child: a case report and review of the literature.

BACKGROUND CONTEXT: Spinal glioblastoma multiforme (GBM) is a rare clinical entity. According to our review of the literature, only 15 cases of spinal GBM originating from the conus medullaris (CM) have been reported. Furthermore, there has been no case of spinal GBM originating from the CM with holocordal and intracranial involvements, which were already present at the time of initial diagnosis. Despite a variety of treatments, the previous studies have uniformly reported poor results of this lethal condition. PURPOSE: The present report illustrates a 10-year-old girl with spinal GBM with rare involvement pattern, that is, the tumor originating from the CM with the holocordal and intracranial involvements, undergoing a novel chemotherapy regimen. STUDY DESIGN: A case report and review of literature. METHODS: Magnetic resonance (MR) imaging with gadolinium enhancement clearly revealed holocordal and intracranial lesions, which were otherwise unidentifiable by plane MR imaging. Open biopsy was performed. After histologic diagnosis, novel chemotherapy regimen, that is, simultaneous high-dose chemotherapy (cyclophosphamide, cisplatin, vincristine, and etoposide) combined with autologous peripheral blood stem cell transplantation (auto-PBSCT), intrathecal injections of both methotrexate and dexamethasone, and radiotherapy, which respected the tolerance threshold of the spinal cord, were performed. RESULTS: Novel chemotherapy regimen achieved marked tumor regression until the 12th month of treatment. The patient became ambulatory with T-shaped canes and has returned to the school life. Unfortunately, the patient died because of the relapse of the tumor 14 months after the initial diagnosis; however, this strategy has achieved longer survival than previously reported mean survival (12 months). CONCLUSIONS: The authors advocate enhanced MR imaging of the whole central nervous system for the potential spreading of this disease. This is the first report of simultaneous high-dose chemotherapy combined with auto-PBSCT, intrathecal injections of antineoplastic agents, and radiotherapy for the treatment of spinal GBM, which achieved marked tumor regression. We believe that accumulated experiences in the treatment of this lethal condition might contribute well to improve its therapeutic outcome.