Chemical Localization With Robotic Bronchoscopy: Can It Aid Resection of Subsolid Lung Nodules?

INTRODUCTION: Subsolid nodules or those located deep in lung parenchyma are difficult to localize using minimally invasive thoracic surgery. While image-guided percutaneous needle localization has been performed, it is inconvenient and has potential complications. In this study, the role of chemical localization using robotic bronchoscopy to facilitate resection was evaluated. METHODS: Consecutive patients undergoing surgical resection for lung nodules between 8/2019-3/2022 were included. Patients with subsolid lung nodules, or small nodules deep in lung parenchyma that were deemed difficult to localize, were chemically localized (CL) using robotic bronchoscopy before resection. Clinico-demographic data were obtained retrospectively using a prospectively maintained database. RESULTS: Localization of lung nodules before resection was performed in 139 patients while 110 patients were not localized. Daily activity score was higher for localized patients. Nodules in the localized group were smaller (P < 0.001) and had similar solid:ground glass ratio. In the localized group, larger margins were observed, and no re-resection of the parenchymal margin was required. Twenty patients in the non-localized group required re-resection intraoperatively due to close pathological margins or inability to locate the nodule in the resected specimen. Operative time was a median of 10-15 min longer for localized patients, P < 0.001. Length of stay was shorter in the localized group (P < 0.05). CONCLUSIONS: Chemical localization of lung nodules using robotic bronchoscopy appears to be a safe and effective method of identifying the location of nodules with small size and less density and aids increased tumor margins intraoperatively.

Rapid Discharge After Anatomic Lung Resection: Is Ambulatory Surgery for Early Lung Cancer Possible?

BACKGROUND: Given resource constraints during the coronavirus disease 2019 pandemic, we explored whether minimally invasive anatomic lung resections for early-stage lung cancer could undergo rapid discharge. METHODS: All patients with clinical stage I-II non-small cell lung cancer from September 2019 to June 2022 who underwent minimally invasive anatomic lung resection at a single institution were included. Patients discharged without a chest tube <18 hours after operation, meeting preset criteria, were considered rapid discharge. Demographics, comorbidities, operative details, and 30-day outcomes were compared between rapid discharge patients and nonrapid discharge "control" patients. Multivariable logistic regression was performed for predictors of nonrapid discharge. RESULTS: Overall, 430 patients underwent resection (200 lobectomies and 230 segmentectomies); 162 patients (37%) underwent rapid discharge and 268 patients (63%) were controls. The rapid discharge group was younger (66.5 vs 70.0 years; P < .001), was assigned to lower American Society of Anesthesiologists class (P = .02), had more segmentectomies than lobectomies (P = .003), and had smaller tumors (P < .001). There were no differences between groups in distance from home to hospital (P = .335) or readmission rates (P = .39). Increasing age had higher odds for nonrapid discharge (odds ratio, 1.04; 95% CI, 1.02-1.07), whereas segmentectomy had decreased odds (odds ratio, 0.46; 95% CI, 0.28-0.75). CONCLUSIONS: Approximately 37% of the patients underwent rapid discharge after operation with similar readmission rate to controls. Increasing age had higher odds for nonrapid discharge; segmentectomy was likely to lead to rapid discharge. Consideration of rapid discharge minimally invasive lung resection for early-stage lung cancer can result in significant reduction in inpatient resources without adverse patient outcomes.

Temporal correlation between postreperfusion complement deposition and severe primary graft dysfunction in lung allografts.

Growing evidence implicates complement in the pathogenesis of primary graft dysfunction (PGD). We hypothesized that early complement activation postreperfusion could predispose to severe PGD grade 3 (PGD-3) at 72 hours, which is associated with worst posttransplant outcomes. Consecutive lung transplant patients (n = 253) from January 2018 through June 2023 underwent timed open allograft biopsies at the end of cold ischemia (internal control) and 30 minutes postreperfusion. PGD-3 at 72 hours occurred in 14% (35/253) of patients; 17% (44/253) revealed positive C4d staining on postreperfusion allograft biopsy, and no biopsy-related complications were encountered. Significantly more patients with PGD-3 at 72 hours had positive C4d staining at 30 minutes postreperfusion compared with those without (51% vs 12%, P < .001). Conversely, patients with positive C4d staining were significantly more likely to develop PGD-3 at 72 hours (41% vs 8%, P < .001) and experienced worse long-term outcomes. In multivariate logistic regression, positive C4d staining remained highly predictive of PGD-3 (odds ratio 7.92, 95% confidence interval 2.97-21.1, P < .001). Hence, early complement deposition in allografts is highly predictive of PGD-3 at 72 hours. Our data support future studies to evaluate the role of complement inhibition in patients with early postreperfusion complement activation to mitigate PGD and improve transplant outcomes.

Association of travel distance, surgical volume, and receipt of adjuvant chemotherapy with survival among patients with resectable lung cancer.

Objective: Regionalization of surgery for non-small cell lung cancer (NSCLC) to high-volume centers (HVCs) improves perioperative outcomes but frequently increases patient travel distance. Travel might decrease rates of adjuvant chemotherapy (AC) use, however, the relationship of distance, volume, and receipt of AC with outcomes is unknown. Our objective was to evaluate the association of distance, volume, and receipt of AC with overall survival among patients with NSCLC. Methods: Patients with stage I to IIIA (N0-N1) NSCLC were identified between 2004 and 2018 using the National Cancer Database. Distance to surgical facility was categorized into quartiles (<5.1, 5.1 to <11.5, 11.5 to <28.1, and ≥28.1 miles), and HVCs were defined as those that perform ≥40 annual resections. Patient characteristics and likelihood of receiving AC anywhere were determined. Propensity score-matched survival analysis was performed using Cox models and Kaplan-Meier curves. Results: Of the 131,982 patients included, 35,658 (27.0%) were stage II to IIIA. Of the stage II to IIIA cohort, 49.6% received AC, 13.1% traveled <5.1 miles to low-volume centers (LVCs), and 18.1% traveled ≥28.1 miles to HVCs (P < .001). Among stage II to IIIA patients who traveled ≥28.1 miles to HVCs, 45% received AC versus 51.5% who traveled <5.1 miles to LVCs (incidence rate ratio, 0.88; 95% CI, 0.83-0.94; <5.1 miles to LVC reference). Patients with stage II to IIIA NSCLC who traveled ≥28.1 miles to HVCs and did not receive AC had higher mortality rates than those who traveled <5.1 miles to LVCs and received AC (median overall survival, 52.3 vs 36.7 months; adjusted hazard ratio, 1.41; 95% CI, 1.26-1.57). Conclusions: Increasing travel distance to surgical treatment is associated with decreased likelihood of receiving AC for patients with stage II to IIIA (N0-N1) NSCLC.

Lung Transplantation in Coronavirus-19 Patients: What We Have Learned So Far.

Coronavirus-19 (COVID-19) can result in irrecoverable acute respiratory distress syndrome (ARDS) or life-limiting fibrosis for which lung transplantation is currently the only viable treatment. COVID-19 lung transplantation has transformed the field of lung transplantation, as before the pandemic, few transplants had been performed in the setting of infectious disease or ARDS. Given the complexities associated with COVID-19 lung transplantation, it requires strict patient selection with an experienced multidisciplinary team in a high-resource hospital setting. Current short-term outcomes of COVID-19 lung transplantation are promising. However, follow-up studies are needed to determine long-term outcomes and whether these patients may be predisposed to unique complications.

Rural-Urban Disparities in Receipt of Surgery for Potentially Resectable Non-Small Cell Lung Cancer.

INTRODUCTION: Access to cancer care, especially surgery, is limited in rural areas. However, the specific reasons rural patient populations do not receive surgery for non-small cell lung cancer (NSCLC) is unknown. We investigated geographic disparities in reasons for failure to receive guideline-indicated surgical treatment for patients with potentially resectable NSCLC. METHODS: The National Cancer Database was used to identify patients with clinical stage I-IIIA (N0-N1) NSCLC between 2004 and 2018. Patients from rural areas were compared to urban areas, and the reason for nonreceipt of surgery was evaluated. Adjusted odds of (1) primary nonsurgical management, (2) surgery being deemed contraindicated due to risk, (3) surgery being recommended but not performed, and (4) overall failure to receive surgery were determined. RESULTS: The study included 324,785 patients with NSCLC with 42,361 (13.0%) from rural areas. Overall, 62.4% of patients from urban areas and 58.8% of patients from rural areas underwent surgery (P < 0.001). Patients from rural areas had increased odds of (1) being recommended primary nonsurgical management (adjusted odds ratio [aOR]: 1.14, 95% confidence interval [CI]: 1.05-1.23), (2) surgery being deemed contraindicated due to risk (aOR: 1.19, 95% CI: 1.07-1.33), (3) surgery being recommended but not performed (aOR: 1.13, 95% CI: 1.01-1.26), and (4) overall failure to receive surgery (aOR: 1.21, 95% CI: 1.13-1.29; all P < 0.001). CONCLUSIONS: There are geographic disparities in the management of NSCLC. Rural patient populations are more likely to fail to undergo surgery for potentially resectable disease for every reason examined.

National trends in the quality of segmentectomy for lung cancer.

OBJECTIVE: Segmentectomy has become an accepted procedure for the treatment of non-small cell lung cancer. Adequate lymph node sampling, sufficient margins, and proper tumor size selection are factors vital for achieving outcomes comparable to lobectomy. Previous studies have demonstrated poor adherence to lymph node sampling guidelines. However, national trends in the quality of segmentectomy and implications on survival are unknown. METHODS: The National Cancer Database was used to identify patients with clinical stage I to IIA non-small cell lung cancer surgically treated between 2004 and 2018. Facility-level trends in extent of resection and segmentectomy odds of adherence to (1) 2014 Commission on Cancer guidelines of sampling 10 or more lymph nodes, (2) negative (R0) resection margins, and (3) tumor size 2 cm or less were determined. Propensity score matching was based on segmentectomy adherence to (4) a composite of all measures, and survival was evaluated with Cox models and Kaplan-Meier survival estimates. RESULTS: The study included 249,391 patients with 4.4% (n = 11,006) treated with segmentectomy. The proportion of segmentectomies performed annually increased from 3.3% in 2004 to 6.1% in 2018 (P < .001). Overall, 12.6% (n = 1385) of patients who underwent segmentectomy between 2004 and 2018 were adherent to all measures, and adherence was more likely at academic programs (odds ratio, 1.56; 95% confidence interval, 1.14-2.15) than nonacademic programs (P < .001, reference). Adherence to all measures was associated with improved survival (hazard ratio, 0.67; 95% confidence interval, 0.56-0.79). CONCLUSIONS: As segmentectomy is increasingly established as a valid oncological option for the treatment of non-small cell lung cancer, it is important that quality remains high. This study demonstrates that continued improvement is needed.

Postreperfusion Pulmonary Artery Pressure Indicates Primary Graft Dysfunction After Lung Transplant.

BACKGROUND: Primary graft dysfunction is a risk factor of early mortality after lung transplant. Models identifying patients at high risk for primary graft dysfunction are limited. We hypothesize high postreperfusion systolic pulmonary artery pressure is a clinical marker for primary graft dysfunction. METHODS: This is a retrospective review of 158 consecutive lung transplants performed at a single academic center from January 2020 through July 2022. Only bilateral lung transplants were included and patients with pretransplant extracorporeal life support were excluded. RESULTS: Primary graft dysfunction occurred in 42.3% (n = 30). Patients with primary graft dysfunction had higher postreperfusion systolic pulmonary artery pressure (41 ± 9.1 mm Hg) than those without (31.5 ± 8.8 mm Hg) (P < .001). Logistic regression showed postreperfusion systolic pulmonary artery pressure is a predictor for primary graft dysfunction (odds ratio 1.14, 95% CI 1.06-1.24, P < .001). Postreperfusion systolic pulmonary artery pressure of 37 mm Hg was optimal for predicting primary graft dysfunction by Youden index. The receiver operating characteristic curve of postreperfusion systolic pulmonary artery pressure at 37 mm Hg (sensitivity 0.77, specificity 0.78, area under the curve 0.81), was superior to the prereperfusion pressure curve at 36 mm Hg (sensitivity 0.77, specificity 0.39, area under the curve 0.57) (P < .01). CONCLUSIONS: Elevated postreperfusion systolic pulmonary artery pressure after lung transplant is predictive of primary graft dysfunction. Postreperfusion systolic pulmonary artery pressure is more indicative of primary graft dysfunction than prereperfusion systolic pulmonary artery pressure. Using postreperfusion systolic pulmonary artery pressure as a positive signal of primary graft dysfunction allows earlier intervention, which could improve outcomes.

Rural-urban survival disparities for patients with surgically treated lung cancer.

BACKGROUND: Nonsmall-cell lung cancer (NSCLC) is a common diagnosis among patients living in rural areas and small towns who face unique challenges accessing care. We examined differences in survival for surgically treated rural and small-town patients compared to those from urban and metropolitan areas. METHODS: The National Cancer Database was used to identify surgically treated NSCLC patients from 2004 to 2016. Patients from rural/small-town counties were compared to urban/metro counties. Differences in patient clinical, sociodemographic, hospital, and travel characteristics were described. Survival differences were examined with Kaplan-Meier curves and Cox proportional hazards models. RESULTS: The study included 366 373 surgically treated NSCLC patients with 12.4% (n = 45 304) categorized as rural/small-town. Rural/small-town patients traveled farther for treatment and were from areas characterized by lower income and education(all p < 0.001). Survival probabilities for rural/small-town patients were worse at 1 year (85% vs. 87%), 5 years (48% vs. 54%), and 10 years (26% vs. 31%) (p < 0.001). Travel distance >100 miles (hazard ratio [HR] = 1.11, 95% confidence interval [CI]: 1.07-1.16, vs. <25 miles) and living in a rural/small-town county (HR = 1.04, 95% CI: 1.01-1.07) were associated with increased risk for death. CONCLUSIONS: Rural and small-town patients with surgically treated NSCLC had worse survival outcomes compared to urban and metropolitan patients.

Clinical Characteristics and Outcomes of Patients With COVID-19-Associated Acute Respiratory Distress Syndrome Who Underwent Lung Transplant.

Importance: Lung transplantation is a potentially lifesaving treatment for patients who are critically ill due to COVID-19-associated acute respiratory distress syndrome (ARDS), but there is limited information about the long-term outcome. Objective: To report the clinical characteristics and outcomes of patients who had COVID-19-associated ARDS and underwent a lung transplant at a single US hospital. Design, Setting, and Participants: Retrospective case series of 102 consecutive patients who underwent a lung transplant at Northwestern University Medical Center in Chicago, Illinois, between January 21, 2020, and September 30, 2021, including 30 patients who had COVID-19-associated ARDS. The date of final follow-up was November 15, 2021. Exposures: Lung transplant. Main Outcomes and Measures: Demographic, clinical, laboratory, and treatment data were collected and analyzed. Outcomes of lung transplant, including postoperative complications, intensive care unit and hospital length of stay, and survival, were recorded. Results: Among the 102 lung transplant recipients, 30 patients (median age, 53 years [range, 27 to 62]; 13 women [43%]) had COVID-19-associated ARDS and 72 patients (median age, 62 years [range, 22 to 74]; 32 women [44%]) had chronic end-stage lung disease without COVID-19. For lung transplant recipients with COVID-19 compared with those without COVID-19, the median lung allocation scores were 85.8 vs 46.7, the median time on the lung transplant waitlist was 11.5 vs 15 days, and preoperative venovenous extracorporeal membrane oxygenation (ECMO) was used in 56.7% vs 1.4%, respectively. During transplant, patients who had COVID-19-associated ARDS received transfusion of a median of 6.5 units of packed red blood cells vs 0 in those without COVID-19, 96.7% vs 62.5% underwent intraoperative venoarterial ECMO, and the median operative time was 8.5 vs 7.4 hours, respectively. Postoperatively, the rates of primary graft dysfunction (grades 1 to 3) within 72 hours were 70% in the COVID-19 cohort vs 20.8% in those without COVID-19, the median time receiving invasive mechanical ventilation was 6.5 vs 2.0 days, the median duration of intensive care unit stay was 18 vs 9 days, the median post-lung transplant hospitalization duration was 28.5 vs 16 days, and 13.3% vs 5.5% required permanent hemodialysis, respectively. None of the lung transplant recipients who had COVID-19-associated ARDS demonstrated antibody-mediated rejection compared with 12.5% in those without COVID-19. At follow-up, all 30 lung transplant recipients who had COVID-19-associated ARDS were alive (median follow-up, 351 days [IQR, 176-555] after transplant) vs 60 patients (83%) who were alive in the non-COVID-19 cohort (median follow-up, 488 days [IQR, 368-570] after lung transplant). Conclusions and Relevance: In this single-center case series of 102 consecutive patients who underwent a lung transplant between January 21, 2020, and September 30, 2021, survival was 100% in the 30 patients who had COVID-19-associated ARDS as of November 15, 2021.

Outcomes after extracorporeal membrane oxygenation support in COVID-19 and non-COVID-19 patients.

BACKGROUND: Veno-venous extracorporeal membrane oxygenation (V-V ECMO) support is increasingly used in the management of COVID-19-related acute respiratory distress syndrome (ARDS). However, the clinical decision-making to initiate V-V ECMO for severe COVID-19 still remains unclear. In order to determine the optimal timing and patient selection, we investigated the outcomes of both COVID-19 and non-COVID-19 patients undergoing V-V ECMO support. METHODS: Overall, 138 patients were included in this study. Patients were stratified into two cohorts: those with COVID-19 and non-COVID-19 ARDS. RESULTS: The survival in patients with COVID-19 was statistically similar to non-COVID-19 patients (p = .16). However, the COVID-19 group demonstrated higher rates of bleeding (p = .03) and thrombotic complications (p < .001). The duration of V-V ECMO support was longer in COVID-19 patients compared to non-COVID-19 patients (29.0 ± 27.5 vs 15.9 ± 19.6 days, p < .01). Most notably, in contrast to the non-COVID-19 group, we found that COVID-19 patients who had been on a ventilator for longer than 7 days prior to ECMO had 100% mortality without a lung transplant. CONCLUSIONS: These findings suggest that COVID-19-associated ARDS was not associated with a higher post-ECMO mortality than non-COVID-19-associated ARDS patients, despite longer duration of extracorporeal support. Early initiation of V-V ECMO is important for improved ECMO outcomes in COVID-19 ARDS patients. Since late initiation of ECMO was associated with extremely high mortality related to lack of pulmonary recovery, it should be used judiciously or as a bridge to lung transplantation.

Lung donation following SARS-CoV-2 infection.

There have been over 177 million cases of COVID-19 worldwide, many of whom could be organ donors. Concomitantly, there is an anticipated increase in the need for donor lungs due to expanding indications. Given that the respiratory tract is most commonly affected by COVID-19, there is an urgent need to develop donor assessment criteria while demonstrating safety and "efficacy" of lung donation following COVID-19 infection. Accordingly, we report an intentional transplant using lungs from a donor with recent, microbiologically confirmed, COVID-19 infection into a recipient suffering from COVID-19 induced ARDS and pulmonary fibrosis. In addition to the standard clinical assays, both donor and recipient lungs were analyzed using RNAscope, which confirmed that tissues were negative for SARS-CoV-2. Immunohistochemistry demonstrated colocalized KRT17+ basaloid-like epithelium and COL1A1+ fibroblasts, a marker suggestive of lung fibrosis in COVID-19 associated lung disease, in the explanted recipient lungs but absent in the donor lungs. We demonstrate that following a thorough assessment, lung donation following resolved COVID-19 infection is safe and feasible.

Paraconduit Hernia in the Era of Minimally Invasive Esophagectomy: Underdiagnosed?

BACKGROUND: There is a need to compare the proportions, risk factors, and natural histories of postesophagectomy paraconduit hernias in minimally invasive and open esophagectomies. METHODS: This is a single-center, retrospective cohort study of esophageal cancer surgery performed between 2007 and 2017. Postesophagectomy paraconduit hernias were identified on cross-sectional imaging. Patient charts were reviewed to describe the management and natural history. RESULTS: Between 2007 and 2017, 391 esophagectomies were performed. After exclusions, 347 patients remained, 135 of whom were total minimally invasive esophagectomies (MIEs) (39%). Postoperative paraconduit hernias developed in 10% of patients. Median time to diagnosis was 258 days. Of 135 MIEs, 20 had a paraconduit hernia (15%) compared with 16 of 212 open or hybrid esophagectomies (8%; P = .03). Hernias were symptomatic in 13 patients (36%) and asymptomatic in 23 (64%), which were detected radiographically. Repair was performed in 11 of 13 symptomatic patients (85%), compared with 3 of 23 asymptomatic patients (13%). In the asymptomatic group, only 1 required emergency repair (4.3%). There was a trend toward a greater proportion of symptomatic paraconduit hernias compared with asymptomatic patients (77% versus 43%; P = .08) in MIE patients. Factors associated with the development of paraconduit hernias on univariate analysis were younger age (P = .02) and not receiving neoadjuvant chemotherapy (P = .01) or neoadjuvant radiation (P = .03). CONCLUSIONS: Postesophagectomy paraconduit hernia is more common after totally minimally invasive esophagectomy compared with open or hybrid techniques. One third are symptomatic and the remainder are detected only radiographically. Repair of asymptomatic hernias consider the patient's cancer prognosis.

Early Rescue from Acute Severe Clostridium Difficile: A Novel Treatment Strategy.

BACKGROUND: Severe Clostridium difficile infections (CDI) can lead to significant impediments to effective treatment. We developed a novel treatment protocol utilizing bedside gastrointestinal lavage (GIL) for the management of patients with severe, complicated CDI. We describe the development and early outcomes of non-operative bedside GIL in hospitalized patients with severe, complicated CDI following the Idea, Development, Exploration, Assessment, Long Term Study (IDEAL) framework at the Idea stage. We compared our results with those of a cohort of patients managed with colectomy. METHODS: We conducted a retrospective cohort study of hospitalized patients with severe, complicated CDI who failed conventional medical therapy and were referred for surgical consultation at two academic tertiary-care hospitals between January 2009 and January 2015. After surgical assessment, the attending surgeon decided to proceed either with bedside GIL or directly to colectomy. Bedside GIL involved nasojejunal tube insertion followed by flushing with 8 L of polyethylene glycol 3350/electrolyte solution over 48 h. Both patient groups received standard medical treatment with vancomycin 500 mg q 6 h enterally and metronidazole 500 mg intravenously three times daily for 14 d. The main outcomes of interest were the incidence of colectomy, complications, and mortality rate. RESULTS: Nineteen and seventeen patients underwent GIL and direct colectomy, respectively. There were no significant differences between the groups in terms of demographics, American Society of Anesthesiologists class, disease severity, need for intensive care unit admission, mechanical ventilation, vasopressor use, serum lactate concentration, or proportion presenting with hypotension, acute kidney injury, or a white blood cell count >16,000/mcL or <4,000/mcL (p > 0.1). The in-hospital mortality rate was 26% (5/19) and 41% (7/17) for the GIL and colectomy groups, respectively (p = 0.35). Only one patient in the GIL group failed the protocol, requiring colectomy. There were no significant differences in complications in the two groups. CONCLUSIONS: Bedside GIL appeared to be safe for the treatment of patients with severe, complicated CDI who had failed conventional medical therapy. It did not appear to increase the risk of morbidity or death compared with the traditional strategy of proceeding directly to colectomy.

ALPPS: challenging the concept of unresectability--a systematic review.

INTRODUCTION: Hepatic resection for malignancy is limited by the amount of liver parenchyma left behind. As a result, two-staged hepatectomy and portal vein occlusion (PVO) have become part of the treatment algorithm. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has been recently described as a method to stimulate rapid and profound hypertrophy. MATERIALS AND METHODS: A systematic review of the literature pertaining to ALPPS was undertaken. Peer-reviewed articles relating to portal vein ligation (PVL) and in situ split (ISS) of the parenchyma were included. RESULTS: To date, ALPPS has been employed for a variety of primary and metastatic liver tumors. In early case series, the perioperative morbidity and mortality was unacceptably high. However with careful patient selection and improved technique, many centers have reported a 0% 90-day mortality. The benefits of ALPPS include hypertrophy of 61-93% over a median 9-14 days, 95-100% completion of the second stage, and high likelihood of R0 resection (86-100%). DISCUSSION: ALPPS is only indicated when a two-stage hepatectomy is necessary and the future liver remnant (FLR) is deemed inadequate (<30%). Use in patients with poor functional status, or advanced age (>70 years) is cautioned. Discretion should be used when considering this in patients with pathology other than colorectal liver metastases (CRLM), especially hilar tumors requiring biliary reconstruction. Biliary ligation during the first stage and routine lymphadenectomy of the hepatoduodenal ligament should be avoided. CONCLUSIONS: A consensus on the indications and contraindications for ALPPS and a standardized operative protocol are needed.

Congenital heart block maternal sera autoantibodies target an extracellular epitope on the α1G T-type calcium channel in human fetal hearts.

BACKGROUND: Congenital heart block (CHB) is a transplacentally acquired autoimmune disease associated with anti-Ro/SSA and anti-La/SSB maternal autoantibodies and is characterized primarily by atrioventricular (AV) block of the fetal heart. This study aims to investigate whether the T-type calcium channel subunit α1G may be a fetal target of maternal sera autoantibodies in CHB. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate differential mRNA expression of the T-type calcium channel CACNA1G (α1G gene) in the AV junction of human fetal hearts compared to the apex (18-22.6 weeks gestation). Using human fetal hearts (20-22 wks gestation), our immunoprecipitation (IP), Western blot analysis and immunofluorescence (IF) staining results, taken together, demonstrate accessibility of the α1G epitope on the surfaces of cardiomyocytes as well as reactivity of maternal serum from CHB affected pregnancies to the α1G protein. By ELISA we demonstrated maternal sera reactivity to α1G was significantly higher in CHB maternal sera compared to controls, and reactivity was epitope mapped to a peptide designated as p305 (corresponding to aa305-319 of the extracellular loop linking transmembrane segments S5-S6 in α1G repeat I). Maternal sera from CHB affected pregnancies also reacted more weakly to the homologous region (7/15 amino acids conserved) of the α1H channel. Electrophysiology experiments with single-cell patch-clamp also demonstrated effects of CHB maternal sera on T-type current in mouse sinoatrial node (SAN) cells. CONCLUSIONS/SIGNIFICANCE: Taken together, these results indicate that CHB maternal sera antibodies readily target an extracellular epitope of α1G T-type calcium channels in human fetal cardiomyocytes. CHB maternal sera also show reactivity for α1H suggesting that autoantibodies can target multiple fetal targets.

Bone marrow-derived progenitor cells in end-stage lung disease patients.

BACKGROUND: Chronic lung diseases are marked by progressive inflammation, tissue damage and remodelling. Bone marrow-derived progenitor cells may contribute to these processes. The objectives of this study were to (1) to quantify CD45⁺Collagen-1⁺ fibrocytes and a novel epithelial-like population of bone marrow-derived cells, which express Clara Cell Secretory Protein, in patients at the time of lung transplant and (2) to evaluate mediators that may act to recruit these cells during injury. METHODS: Using an observational design, progenitor cells were quantified by flow cytometry from both bone marrow (BM) and peripheral blood (PB). Migration was tested using in vitro transwell assays. Multiplex bead-based assays were used to quantify plasma cytokines. RESULTS: An increase in CD45⁺Collagen-1⁺ fibrocytes was found in pulmonary fibrosis and bronchiolitis obliterans patients. Cystic fibrosis patients had an increase in CCSP⁺ cells in both the BM and PB. The proportion of CCSP⁺ cells in the BM and PB was correlated. CCSP+ cells express the chemokine receptors CCR2, CCR4, CXCR3, and CXCR4, and significantly migrated in vitro toward Stromal Derived Factor-1 (SDF-1) and Stem Cell Growth Factor-ß (SCGF-ß). Plasma cytokine levels differed between disease groups, with a significant correlation between SCGF-ß and CCSP⁺ cells and between Monocyte Chemotactic Protein-1 and fibrocytes. CONCLUSIONS: Different bone marrow-derived cells are found in various lung diseases. Increased fibrocytes were associated with fibrotic lung diseases. An increase in the novel CCSP⁺ epithelial-like progenitors in cystic fibrosis patients was found. These differences may be mediated by alterations in plasma cytokines responsible for cell recruitment.