Dongni Hou

High-Throughput Sequencing-Based Immune Repertoire Study during Infectious Disease

The selectivity of the adaptive immune response is based on the enormous diversity of T and B cell antigen-specific receptors. The immune repertoire, the collection of T and B cells with functional diversity in the circulatory system at any given time, is dynamic and reflects the essence of immune selectivity. In this article, we review the recent advances in immune repertoire study of infectious diseases, which were achieved by traditional techniques and high-throughput sequencing (HTS) techniques. HTS techniques enable the determination of complementary regions of lymphocyte receptors with unprecedented efficiency and scale. This progress in methodology enhances the understanding of immunologic changes during pathogen challenge and also provides a basis for further development of novel diagnostic markers, immunotherapies, and vaccines.

Immune Repertoire Diversity Correlated with Mortality in Avian Influenza A (H7N9) Virus Infected Patients

Specific changes in immune repertoires at genetic level responding to the lethal H7N9 virus are still poorly understood. We performed deep sequencing on the T and B cells from patients recently infected with H7N9 to explore the correlation between clinical outcomes and immune repertoire alterations. T and B cell repertoires display highly dynamic yet distinct clonotype alterations. During infection, T cell beta chain repertoire continues to contract while the diversity of immunoglobulin heavy chain repertoire recovers. Patient recovery is correlated to the diversity of T cell and B cell repertoires in different ways – higher B cell diversity and lower T cell diversity are found in survivors. The sequences clonally related to known antibodies with binding affinity to H7 hemagglutinin could be identified from survivors. These findings suggest that utilizing deep sequencing may improve prognostication during influenza infection and could help in development of antibody discovery methodologies for the treatment of virus infection.

The Mechanism of MSCs Therapy in Acute Respiratory Distress Syndrome

In past decades, acute respiratory distress syndrome (ARDS) has been associated with high mortality and morbidity. Although many maneuvers have been tested including tens of clinical trials, so far there is still no approved pharmacological intervention available for ARDS except protective ventilation strategy. Mesenchymal stem cells (MSCs) has shown improved survival in various ARDS animal model after administration. Here we summarized the updates of MSC derivation and purification, administration approaches, timing of MSC delivery, and mechanism of MSC therapy in order to provide a state-of-art paradigm of cell based therapy in ARDS and to facilitate the development of MSC therapy in ARDS patients.

The Expression of Dectin-1, Irak1 and Rip2 During the Host Response to Aspergillus fumigatus

BackgroundC-type lectin receptors (CLRs), Toll-like receptors (TLRs), and Nod-like receptors (NLRs) have the ability to recognize Aspergillus fumigatus (A. fumigates) and induce innate immune response. Dectin-1 is a well-described CLR, while interleukin-1 receptor-associated kinase 1 (Irak1) and receptor-interacting protein 2 (Rip2) are pivotal adaptor proteins of TLRs and NLRs signaling pathways, respectively.ObjectivesOur primary aim is to elucidate whether Dectin-1 regulates the expression of Irak1 and Rip2, and confirm that CLRs, TLRs, and NLRs pathways act synergistically in response to A. fumigatus infection.MethodsPulmonary infection mouse models were established. Myeloid cells were differentiated in cell culture and examined by inverted microscopy, flow cytometry, and scanning electron microscopy. The relative mRNA levels were determined by qRT-PCR. The protein expression levels were determined by immunohistochemistry and Western blot.ResultsThe expression of Dectin-1, Irak1, Rip2, and phosphorylation level of nuclear factor (NF)-κB p65 were induced by conidia in immunocompetent mice, while their expression and phosphorylation level were inhibited in immunocompromised mice after the administration of conidia. Conidia increased the expression of Dectin-1, Irak1, and Rip2 in myeloid cells, while Dectin-1 silencing significantly reduced their expression.ConclusionOur findings demonstrate that Dectin-1, Irak1, and Rip2 are involved in response to A. fumigatus infection. Dectin-1 modulates the expression of Irak1 and Rip2. Additionally, these three signaling pathways are interconnected, and CLRs pathway plays a dominant role against A. fumigatus invasion.

Status of coexisting chronic obstructive pulmonary disease and its clinicopathological features in patients undergoing lung cancer surgery: a cross-sectional study of 3,006 cases

Background Lung cancer is often complicated with chronic obstructive pulmonary disease (COPD). Coexistence of COPD has significant impacts on the decision-making process for lung cancer surgery as well as the postoperative effects. This study aimed to investigate the status of coexisting COPD and analyze its clinicopathological characteristics in lung cancer patients undergoing surgical resection. Methods Clinical data of 3,006 patients with resected primary lung cancer from January 2008 to April 2014 were analyzed. Status of coexisting COPD was evaluated according to patients lung function. Differences of clinicopathological characteristics between the COPD group and the non-COPD group were compared. Results A total of 643 patients (21.4%) were complicated with COPD. The average age of patients with COPD (64.9±8.5 years) was significantly older than those without COPD (59.4±9.9 years). The percentage of males (85.7% vs. 54.0%) and current smokers (43.4% vs. 22.5%) were both higher in the COPD group than the non-COPD group (P<0.05). The percentage of patients with initial symptoms was higher in the COPD group than the non-COPD group (63.9% vs. 44.5%, P<0.05). The average white blood cell count was higher in the COPD group than the non-COPD group [(6.72±2.28 vs. 6.28±2.24) ×109/L, P<0.05]. The percentage of tumor size more than 3 cm was higher in the COPD group than the non-COPD group (53.2% vs. 38.0%, P<0.05). Squamous cell carcinoma accounted for 47.6% in the COPD group while adenocarcinoma accounted for 72.4% in the non-COPD group (P<0.05). A higher percentage of lung cancer with poor differentiation was found in the COPD group than the non-COPD group (53.2% vs. 43.6%, P<0.05). The median total and postoperative length of hospital stay were significantly longer in the COPD group than the non-COPD group (13 vs. 11 days, 8 vs. 7 days, respectively, P<0.05). Conclusions COPD is a common comorbidity of early stage lung cancer. Lung cancer patients with coexistence of COPD have obviously different clinicopathological features compared to patients without COPD, which requires special attention and management during the perioperative period of lung cancer.

Neutrophil-to-lymphocyte ratio as a prognostic marker in acute respiratory distress syndrome patients: a retrospective study

Background Acute respiratory distress syndrome (ARDS) is the leading cause of high mortality in intensive care units (ICUs) worldwide. An effective marker for prognosis in ARDS is particularly important given the absence of effective treatment strategies aside from small tidal volume ventilation. Previous studies identified an association between the neutrophil-to-lymphocyte ratio (NLR) and prognosis in critical patients. In this study, we explored the prognostic and predictive value of the NLR in ARDS patients. Methods We retrospectively included 275 ARDS patients treated at a single institute from 2008 to 2015. After excluding patients with chronic lung disease, acute myocardial infarction and missing data, 247 patients were ultimately included in the analysis. Clinical characteristics and experimental test data, including the NLR, were collected from medical records at 24 hours after the ARDS diagnosis. Independent prognostic factors were determined by multivariate Cox regression analysis. Subgroup stratification was performed according to different factors, and the continuous factors were divided according to the median values. Results The NLR in survivors was significantly lower than that in non-survivors (P<0.001). We took the median NLR value as the cut-off point and further divided all patients into a high NLR group (NLR >14) and a low NLR group (NLR ≤14). We found that an NLR >14 was associated with a shorter overall survival (OS) (P=0.005). In the multivariate Cox regression model, we further identified an NLR >14 as an independent prognostic factor for OS [hazard ratio (HR) 1.532, (95% CI, 1.095-2.143), P=0.013]. Subgroup analysis showed that the prognostic value of the NLR was higher in hypertensive patients (P=0.009) and in patients with low red blood cell specific volume (P=0.013), high sodium (P=0.002) and high creatinine levels (P=0.017). Conclusions The NLR is potentially a predictive prognostic biomarker in ARDS patients.

Risk factors for mortality in ICU patients with Acinetobacter baumannii ventilator-associated pneumonia: impact of bacterial cytotoxicity

Background Acinetobacter baumannii (A. baumannii) ventilator-associated pneumonia (VAP) in intensive care unit (ICU) is associated with high morbidity and mortality in patients with critical illness. However, the literatures that focused on the short-term prognosis and the risk factors for mortality are limited. The aim of this study was to evaluate the risk factors for mortality in ICU patients with A. baumannii VAP. Methods A retrospective cohort study was conducted in the medical/surgical ICU at Zhongshan Hospital in Shanghai, China. Adult patients meeting the criteria of A. baumannii VAP from January 2012 to October 2015 were enrolled. Apart from collecting clinical and microbiologic data, we performed biofilm-formation and cytotoxicity testing using A. baumannii strains which are isolated from patients. Multivariate logistic regression analysis was used to determine the independent risk factors for 30-day mortality in ICU. Results Seventy-eight patients were included in this study. The 30-day mortality rate in ICU for the patients was 37.2%. Multivariate analysis revealed that short-term mortality was significantly associated with prior surgery [OR, 0.277; 95% confidence interval (CI), 0.089-0.866; P=0.027], higher APACHEII score (OR, 1.140; 95% CI, 1.007-1.291; P=0.038) and an increased bacterial cytotoxicity (OR, 1.029 ; 95% CI, 1.001-1.058; P=0.047). Conclusions The main finding of our study was that increased bacterial cytotoxicity might be a risk factor for short-term mortality in ICU patients with A. baumannii VAP.

Prevalence of and risk factors for presenting initial respiratory symptoms in patients undergoing surgery for lung cancer

Background: Patients with early stage lung cancer seldom present initial respiratory symptoms, causing a delayed diagnosis and missed opportunity to receive operation. This study aimed to investigate the prevalence of initial respiratory symptoms and identity what factors would predispose lung cancer patients to present initial respiratory symptoms in patients undergoing lung cancer surgery. Methods: A retrospective chart review was conducted on 3,203 patients undergoing surgery for primary lung cancer. The prevalence of initial respiratory symptoms was investigated and the comparisons of clinicopathological parameters were performed between patients with and without initial respiratory symptoms or between patients with single and multiple initial respiratory symptoms. Independent risk factors for presenting initial respiratory symptoms or multiple initial respiratory symptoms were identified using a logistic regression. Results: A total of 1,474 (46.0%) patients with lung cancer were admitted to hospital due to present initial respiratory symptoms. Symptom clusters of cough or sputum (33.1%) and bloody sputum or hemoptysis (16.7%) presented as the two major chief complaints for medical consultation while chest pain (6.9%) and chest distress or dyspnea (5.6%) remained relatively unusual. Multiple analyses found that coexisting chronic obstructive pulmonary disease (OR=1.70, 95% CI=1.41—2.05), tumor size >3 cm (OR=2.27, 95% CI=1.93—2.67), squamous cell carcinoma (OR=2.22, 95% CI=1.86—2.65), tumor located in left lower lung (OR=1.39, 95% CI=1.10—1.74) and advanced tumor stage (OR=1.27, 95% CI=1.06—1.52) were independent risk factors for presenting initial respiratory symptoms. Furthermore, current smoking (OR=1.36, 95% CI=1.07—1.73), tumor size >3 cm (OR=1.53, 95% CI=1.21—1.93) and squamous cell carcinoma (OR=1.68, 95% CI=1.32—2.15) were demonstrated to be independent risk factors for presenting multiple initial respiratory symptoms. Conclusions: Presenting initial respiratory symptoms was the common cause for medical consultation in patients undergoing lung cancer surgery. Patients with lung cancer in larger tumor size or squamous cell carcinoma more likely presented initial and even multiple initial respiratory symptoms.

Lung cancer patients with a previous extra-pulmonary malignancy should not be considered homogeneous: a clinicopathological analysis of 3530 surgical cases

BackgroundLung cancer patients with a previous extra-pulmonary malignancy have been widely discussed for their postoperative prognosis. Still, whether different types of previous extra-pulmonary malignancy confer different clinicopathological features and outcomes of lung cancer patients deserves further investigation.MethodsThe medical records of patients undergoing operation for pulmonary malignancy were retrospectively reviewed. After identifying primary lung cancer out of pulmonary metastasis in patients with a history of previous extra-pulmonary malignancy, clinicopathological parameters and postoperative prognosis were compared between lung cancer patients without and with different types of previous extra-pulmonary malignancy.ResultsApproximately, 5.0% lung cancer patients undergoing surgery had a previous extra-pulmonary malignancy. Prior breast cancer (20%) and colorectal cancer (16%) formed the majority of these previous extra-pulmonary malignancies. Many clinicopathological features such as reason for visit, tumor size and histological subtype were significantly different between lung cancer patients without and with different types of previous extra-pulmonary malignancy (P < 0.05). Lung cancer patients with a previous occurrence of breast cancer were the most different type from patients without a previous extra-pulmonary malignancy in clinicopathological features (P < 0.05). The postoperative overall survival was not significantly different between lung cancer patients without and with different types of previous extra-pulmonary malignancy (P > 0.05).ConclusionPrevious extra-pulmonary malignancy was confirmed to be harmless to postoperative prognosis of lung cancer patients. Lung cancer patients with a previous extra-pulmonary malignancy, especially with a previous occurrence of breast cancer, were highly heterogeneous in clinicopathological features. These findings implied there might be a unique etiology existing in lung cancer following a previous occurrence of breast cancer.

Long-term Follow-up of 5 Survivors after the First Outbreak of Human Infections with Avian Influenza A(H7N9) Virus in Shanghai, China

At the end of March 2013, the first case of human infection with avian influenza A(H7N9) virus was confirmed in Shanghai. From April to May 2013, 18 patients with avian influenza A(H7N9) virus infection were hospitalized in Shanghai Public Health Clinical Center, and finally, 12 of them survived. The short-term prognosis of these patients had been described previously,[1] but the long-term prognosis remained unclear.