Objective:To investigate the effects of Vibrio vulnificus ( Vv) quorum-sensing protein LuxS on the homeostasis of pulmonary innate immune cells in sepsis-induced acute lung injury. Methods:This study constructed luxS knockout and complemented Vv strains. The time required for wild type, luxS knockout, and complemented Vv strains to grow to an absorbance of 600 nm in liquid medium was measured using a spectrophotometer. Iron-overloaded mice were intraperitoneally infected with 1×10 5 CFU of the above three kinds of Vv strains, respectively. Clinical scoring for sepsis-induced dyspnea was used to evaluate the respiratory quality in mice. At 7 h after infection, the pathological changes in lung tissues were observed by HE staining; the bacterial loads in lung tissues were measured; the single-cell suspension of lung tissues was analyzed by flow cytometry. Uniform manifold approximation and projection (UMAP) was used to reduce the dimension of the distribution of CD45 + immune cells in lung tissues of mice in the PBS control group and infection groups with different strains. The frequency and absolute number of innate immune cells in lung tissues were analyzed by multicolor flow cytometry. One-way analysis of variance and t test were used for statistical analysis. Results:There was no significant difference in the growth rate of wild type, luxS knockout, and complemented Vv strains in liquid medium. Compared with the mice infected with the wild type or complemented strain, the mice infected with the luxS knockout strain exhibited overall alleviated respiratory difficulty, decreased inflammatory cell infiltration in lung tissues, and reduced bacterial load in lung tissues ( P<0.05). Besides, there was no significant difference in clinical respiratory scores, inflammatory cell infiltration, or bacterial loads between the mice infected with the complemented strain and wild type strain. UMAP analysis showed that compared with the mice infected with the luxS knockout strain, the mice infected with the wild type or complemented strain showed increased proportions of neutrophils and eosinophils in lung tissues. Results of multicolor flow cytometry analysis further verified that the proportions of neutrophils and eosinophils were significantly lower in the mice infected with the luxS knockout strain than in the mice infected with wild type or complemented strain ( P<0.01, P<0.000 1), while the proportion of alveolar macrophages was significantly higher as compared with that in the mice infected with wild type or complemented strain ( P<0.01). Conclusion:During Vv infection, LuxS may promote acute lung injury by affecting the homeostasis of neutrophils, eosinophils and resident macrophages in lung tissues.

Objective:To investigate the role of autophagy in the regulatory of phagocytosis in Vibrio vulnificus ( V. vulnificus)-infected murine macrophages. Methods:The expression of cellular autophagy-related proteins in PBS-treated and V. vulnificus-infected RAW264.7 and BMMφ cells was detected by Western blot. The co-localization of V. vulnificus-GFP and LC3Ⅱ protein in V. vulnificus-GFP-infected RAW264.7 and BMMφ cells were detected using confocal microscopy. The phagocytosis of V. vulnificus in V. vulnificus-GFP-infected RAW264.7 and BMMφ cells with or without autophagy inhibition using Bafilomycin A1 was detected by flow cytometry. Results:The up-regulated levels of Atg7, Atg12 and Atg16L1 proteins, increased LC3Ⅱ/actin ratio, as well as down-regulated p62 protein levels were significantly detected in V. vulnificus-infected RAW264.7 and BMMφ cells. The co-localization of V. vulnificus-GFP and LC3Ⅱ protein was clearly observed in V. vulnificus-GFP-infected RAW264.7 and BMMφ cells. Enhanced phagocytosis of V. vulnificus and increased autophagy were exhibited in V. vulnificus-GFP-infected RAW264.7 and BMMφ cells, while weakened phagocytosis, accumulation of Atg7, Atg12, Atg16L1, LC3Ⅱ and p62 protein levels, as well as blocking autophagy flux were detected in those cells within autophagy inhibition using Bafilomycin A1. Conclusion:Autophagy induced by V. vulnificus infection could promote phagocytosis of V. vulnificus in macrophages.

Objective:To investigate the effects of Vibrio vulnificus ( Vv) quorum-sensing protein LuxS on the homeostasis of pulmonary innate immune cells in sepsis-induced acute lung injury. Methods:This study constructed luxS knockout and complemented Vv strains. The time required for wild type, luxS knockout, and complemented Vv strains to grow to an absorbance of 600 nm in liquid medium was measured using a spectrophotometer. Iron-overloaded mice were intraperitoneally infected with 1×10 5 CFU of the above three kinds of Vv strains, respectively. Clinical scoring for sepsis-induced dyspnea was used to evaluate the respiratory quality in mice. At 7 h after infection, the pathological changes in lung tissues were observed by HE staining; the bacterial loads in lung tissues were measured; the single-cell suspension of lung tissues was analyzed by flow cytometry. Uniform manifold approximation and projection (UMAP) was used to reduce the dimension of the distribution of CD45 + immune cells in lung tissues of mice in the PBS control group and infection groups with different strains. The frequency and absolute number of innate immune cells in lung tissues were analyzed by multicolor flow cytometry. One-way analysis of variance and t test were used for statistical analysis. Results:There was no significant difference in the growth rate of wild type, luxS knockout, and complemented Vv strains in liquid medium. Compared with the mice infected with the wild type or complemented strain, the mice infected with the luxS knockout strain exhibited overall alleviated respiratory difficulty, decreased inflammatory cell infiltration in lung tissues, and reduced bacterial load in lung tissues ( P<0.05). Besides, there was no significant difference in clinical respiratory scores, inflammatory cell infiltration, or bacterial loads between the mice infected with the complemented strain and wild type strain. UMAP analysis showed that compared with the mice infected with the luxS knockout strain, the mice infected with the wild type or complemented strain showed increased proportions of neutrophils and eosinophils in lung tissues. Results of multicolor flow cytometry analysis further verified that the proportions of neutrophils and eosinophils were significantly lower in the mice infected with the luxS knockout strain than in the mice infected with wild type or complemented strain ( P<0.01, P<0.000 1), while the proportion of alveolar macrophages was significantly higher as compared with that in the mice infected with wild type or complemented strain ( P<0.01). Conclusion:During Vv infection, LuxS may promote acute lung injury by affecting the homeostasis of neutrophils, eosinophils and resident macrophages in lung tissues.

Objective:To investigate the role of autophagy in the regulatory of phagocytosis in Vibrio vulnificus ( V. vulnificus)-infected murine macrophages. Methods:The expression of cellular autophagy-related proteins in PBS-treated and V. vulnificus-infected RAW264.7 and BMMφ cells was detected by Western blot. The co-localization of V. vulnificus-GFP and LC3Ⅱ protein in V. vulnificus-GFP-infected RAW264.7 and BMMφ cells were detected using confocal microscopy. The phagocytosis of V. vulnificus in V. vulnificus-GFP-infected RAW264.7 and BMMφ cells with or without autophagy inhibition using Bafilomycin A1 was detected by flow cytometry. Results:The up-regulated levels of Atg7, Atg12 and Atg16L1 proteins, increased LC3Ⅱ/actin ratio, as well as down-regulated p62 protein levels were significantly detected in V. vulnificus-infected RAW264.7 and BMMφ cells. The co-localization of V. vulnificus-GFP and LC3Ⅱ protein was clearly observed in V. vulnificus-GFP-infected RAW264.7 and BMMφ cells. Enhanced phagocytosis of V. vulnificus and increased autophagy were exhibited in V. vulnificus-GFP-infected RAW264.7 and BMMφ cells, while weakened phagocytosis, accumulation of Atg7, Atg12, Atg16L1, LC3Ⅱ and p62 protein levels, as well as blocking autophagy flux were detected in those cells within autophagy inhibition using Bafilomycin A1. Conclusion:Autophagy induced by V. vulnificus infection could promote phagocytosis of V. vulnificus in macrophages.

Objective To investigate the prenatal diagnosis and postnatal clinical outcomes of fetal congenital choledochal cyst (CCC) to improve the recognition and treatment of fetal CCC.Methods Clinical data of 23 cases of fetal CCC which were diagnosed during routine prenatal ultrasonic examination in Jinhua Municipal Central Hospital from June 2009 to May 2015 were retrospectively analyzzed. Maternal age, gestational age at diagnosis of CCC, location and size of cyst, postnatal examination, age at operation and follow-up outcomes were recorded and statistically analyzed by Wilcoxon rank-sum test.Results (1) Among the 23 cases, six (26%) were terminated and the rest 17 continued their pregnancies (74%). (2) Results of the prenatal ultrasonography of the 23 cases indicated that hepatic portal cysts were closely related to hepatic portal veins or arteries. Six of the cysts communicated with gall bladder and eight connected to intrahepatic bile duct. The maximum diameter of the cysts in the 23 cases was 16.0-31.0 mm, averagely (24.7±3.7) mm. The maximum diameter of cysts diagnosed in the third trimester was significantly larger than that in the second trimester [ 27.0 (22.0-31.0) vs 23.0 (21.0-25.0) mm,Z=-2.134,P<0.05]. (3) Among the 17 cases of continued pregnancy, one underwent cesarean section at 35+ weeks of gestation and 16 delivered at term with the average gestational age at delivery of (38.2±1.1) weeks. All neonates were re-examined by abdominal ultrasound at 1-2 postnatal weeks and confimed prenatal diagnosed of CCC. (4) The 17 neonates were re-examined by abdominal ultrasound during the second postnatal week and the results showed that cyst size remained the same in four, decreased in one and gradually increased with the gestational age in 12 neonates. Among the 16 cases of confirmed CCC, 12 received surgery, including 11 (Ⅰa, 6;Ⅰc, 3;Ⅳb, 2) within one year-old and one (Ⅰc) around 18 months old. The prognosis was uneventful. Four out of the 16 cases rejected surgical operation and were followed up in outpatient. One neonate was diagnosed with congenital biliary atresia and transferred to Children's Hospital for operation.Conclusions When fetal abdominal cyst presented with hepatic portal cyst which communicates with gallbladder or intra-hepatic duct in ultrasonography, a congenital choledochal cyst should be taken into consideration by excluding the possibility of biliary atresia in the first place. Surgery for CCC infants without symptoms or signs is suggested to be performed around three months after birth. The postoperative prognosis of CCC is favorable, so termination is not recommended for gravidas with fetal CCC in prenatal consultation.