Dissecting intratumoral myeloid cell plasticity by single cell RNA-seq.

Tumor-infiltrating myeloid cells are the most abundant leukocyte population within tumors. Molecular cues from the tumor microenvironment promote the differentiation of immature myeloid cells toward an immunosuppressive phenotype. However, the in situ dynamics of the transcriptional reprogramming underlying this process are poorly understood. Therefore, we applied single cell RNA-seq (scRNA-seq) to computationally investigate the cellular composition and transcriptional dynamics of tumor and adjacent normal tissues from 4 early-stage non-small cell lung cancer (NSCLC) patients. Our scRNA-seq analyses identified 11 485 cells that varied in identity and gene expression traits between normal and tumor tissues. Among these, myeloid cell populations exhibited the most diverse changes between tumor and normal tissues, consistent with tumor-mediated reprogramming. Through trajectory analysis, we identified a differentiation path from CD14+ monocytes to M2 macrophages (monocyte-to-M2). This differentiation path was reproducible across patients, accompanied by increased expression of genes (eg, MRC1/CD206, MSR1/CD204, PPARG, TREM2) with significantly enriched functions (Oxidative phosphorylation and P53 pathway) and decreased expression of genes (eg, CXCL2, IL1B) with significantly enriched functions (TNF-α signaling via NF-κB and inflammatory response). Our analysis further identified a co-regulatory network implicating upstream transcription factors (JUN, NFKBIA) in monocyte-to-M2 differentiation, and activated ligand-receptor interactions (eg, SFTPA1-TLR2, ICAM1-ITGAM) suggesting intratumoral mechanisms whereby epithelial cells stimulate monocyte-to-M2 differentiation. Overall, our study identified the prevalent monocyte-to-M2 differentiation in NSCLC, accompanied by an intricate transcriptional reprogramming mediated by specific transcriptional activators and intercellular crosstalk involving ligand-receptor interactions.

Ex Vivo Modeling of Perioperative Air Leaks in Porcine Lungs.

OBJECTIVE: A novel ex vivo model is described to advance the understanding of prolonged air leaks, one of the most common postoperative complications following thoracic resection procedures. METHODS: As an alternative to in vivo testing, an ex vivo model simulating the various physiologic environments experienced by an isolated lung during the perioperative period was designed and built. Isolated porcine lungs were perfused and ventilated during open chest and closed chest simulations, mimicking intra and postoperative ventilation conditions. To assess and validate system capabilities, nine porcine lungs were tested by creating a standardized injury to create an approximately 250 cc/min air leak. Air leak rates, physiologic ventilation, and perfusion parameters were continuously monitored, while gas transfer analysis was performed on selected lungs. Segmental ventilation was monitored using electrical impedance tomography. RESULTS: The evaluated lungs produced flow-volume and pressure-volume loops that approximated standard clinical representations under positive (mechanical) and negative (physiological) pressure ventilation modalities. Leak rate was averaged across the ventilation phases, and sharp increases in leak rate were observed between positive and negative pressure phases, suggesting that differences or changes in ventilation mechanics may strongly influence leak development. CONCLUSION: The successful design and validation of a novel ex vivo lung model was achieved. Model output paralleled clinical observations. Pressure modality may also play a significant role in air leak severity. SIGNIFICANCE: This work provides a foundation for future studies aimed at increasing the understanding of air leaks to better inform means of mitigating the risk of air leaks under clinically relevant conditions.

Navigational bronchoscopy at a community hospital: clinical and economic outcomes.

AIM: To evaluate the clinical and financial impact of introducing electromagnetic navigation bronchoscopy (ENB) at a community center. METHODS: This retrospective, single-arm, single-center study evaluated 90 consecutive patients who had undergone ENB in 2012. Radial probe endobronchial ultrasound was used to localize the lesion after initial ENB. ENB-aided diagnoses, follow-up procedures and treatments, and adverse events were collected through 2 years. RESULTS: ENB was conducted for lung biopsy (86 patients), fiducial placement (five), and/or dye marking (two). ENB-aided diagnostic yield was 82.6% (71/86), including 36 malignant and 35 nonmalignant cases. NSCLC was stage I-II in 84.6%. There were four false negatives. Sensitivity and negative predictive value were 90.0 and 88.6%. Pneumothorax occurred in 6/90 (5/6 with chest tube) and minor bleeding in four. The downstream revenue of new ENB cases was US$363,654. CONCLUSION: ENB introduction provided high diagnostic yield, early-stage diagnosis, acceptable safety, and was financially justified.

Long-term detrimental effect of bile duct injury on health-related quality of life.

HYPOTHESIS: Long-term quality of life (QOL) in patients undergoing laparoscopic cholecystectomy (LC) incurring bile duct injury (BDI) and repair is comparable to that of patients undergoing uncomplicated LC. DESIGN: Case comparison study. SETTING: Secondary and tertiary care centers. PATIENTS: Eighty-six patients incurring BDI during LC between January 1, 1991, and July 31, 2003, were surveyed. Comparison subjects underwent uncomplicated LC during the same period. MAIN OUTCOME MEASURES: Health-related QOL as assessed by the Karnofsky Performance Scale, Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), and Psychosocial Adjustment to Illness Scale. RESULTS: Fifty patients with BDI (39 [78%] female; mean +/- SEM age, 55 +/- 2 years) and 74 patients with uncomplicated LC (51 [69%] female, mean +/- SEM age, 52 +/- 2 years) responded. Of the 50 BDI patients, 48 (96%) had no stricture and normal liver function at QOL assessment. The mean +/- SEM follow-up period to QOL assessment for the BDI and uncomplicated LC groups was 62 +/- 6 and 47 +/- 3 months, respectively. The mean +/- SD Karnofsky Performance Scale scores were 77 +/- 9 vs 93 +/- 8 for the 2 groups, respectively (P <.001). The mean +/- SD SF-36 physical component scale scores after BDI vs uncomplicated LC were 36 +/- 11 vs 47 +/- 12, respectively (P <.001), compared with 50 +/- 10 for the normal population (P <.001). The mean +/- SD SF-36 mental component scale scores were 43 +/- 14 vs 49 +/- 11 for the 2 groups, respectively (P =.02), compared with 50 +/- 10 for the normal population (P =.01). Patients with BDI scored poorer on the Psychosocial Adjustment to Illness Scale health care orientation and domestic environment scales (P=.01). CONCLUSION: After BDI and repair, there are long-term detrimental effects of BDI on health-related QOL.