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Remote interventions are increasingly utilized in transplant medicine but have rarely been rigorously evaluated. We investigated a remote intervention targeting immunosuppressant management in pediatric lung transplant recipients. Patients were recruited from a larger multisite trial if they had a Medication Level Variability Index (MLVI) ≥ 2.0, indicating worrisome tacrolimus level fluctuation. The manualized intervention included 3 weekly phone calls and regular follow-up calls. A comparison group included patients who met enrollment criteria after the sub-protocol ended. Outcomes were defined before the intent-to-treat analysis. Feasibility was defined as ≥ 50% of participants completing the weekly calls. MLVI was compared pre- and 180 days post-enrollment and between intervention and comparison groups. Of 18 eligible patients, 15 enrolled. Seven additional patients served as the comparison. Seventy-five percent of participants completed ≥ 3 weekly calls; average time on protocol was 257.7 days. Average intervention group MLVI was significantly lower (indicating improved blood level stability) at 180 days post-enrollment (2.9 ± 1.29) compared to pre-enrollment (4.6 ± 2.10), p=0.02. At 180 days, MLVI decreased by 1.6 points in the intervention group, but increased by 0.6 in the comparison group (p=0.054). Participants successfully engaged in a long-term remote intervention, and their medication blood levels stabilized. NCT02266888.

Summary The increasing global prevalence of SARS‐CoV‐2 and the resulting COVID‐19 disease pandemic pose significant concerns for clinical management of solid organ transplant recipients (SOTR). Wearable devices that can measure physiologic changes in biometrics including heart rate, heart rate variability, body temperature, respiratory, activity (such as steps taken per day) and sleep patterns, and blood oxygen saturation show utility for the early detection of infection before clinical presentation of symptoms. Recent algorithms developed using preliminary wearable datasets show that SARS‐CoV‐2 is detectable before clinical symptoms in >80% of adults. Early detection of SARS‐CoV‐2, influenza, and other pathogens in SOTR, and their household members, could facilitate early interventions such as self‐isolation and early clinical management of relevant infection(s). Ongoing studies testing the utility of wearable devices such as smartwatches for early detection of SARS‐CoV‐2 and other infections in the general population are reviewed here, along with the practical challenges to implementing these processes at scale in pediatric and adult SOTR, and their household members. The resources and logistics, including transplant‐specific analyses pipelines to account for confounders such as polypharmacy and comorbidities, required in studies of pediatric and adult SOTR for the robust early detection of SARS‐CoV‐2, and other infections are also reviewed.

Background Infection with rhinovirus (HRV) occurs following pediatric lung transplantation. Prospective studies documenting frequencies, persistence, and progression of HRV in this at-risk population are lacking. Methods In the Clinical Trials in Organ Transplant in Children prospective observational study, we followed 61 lung transplant recipients for 2 years. We quantified molecular subtypes of HRV in serially collected nasopharyngeal (NP) and bronchoalveolar lavage (BAL) samples and correlated them with clinical characteristics. Results We identified 135 community-acquired respiratory infections (CARV) from 397 BAL and 480 NP samples. We detected 93 HRV events in 42 (68.8%) patients, 22 of which (23.4%) were symptomatic. HRV events were contiguous with different genotypes identified in 23 cases, but symptoms were not preferentially associated with any particular species. Nine (9.7%) HRV events persisted over multiple successive samples for a median of 36 days (range 18-408 days). Three persistent HRV were symptomatic. When we serially measured forced expiratory volume in one second (FEV1) in 23 subjects with events, we did not observe significant decreases in lung function over 12 months post-HRV. Conclusion In conjunction with our previous reports, our prospectively collected data indicate that molecularly heterogeneous HRV infections occur commonly following pediatric lung transplantation, but these infections do not negatively impact clinical outcomes.

Recipient adolescent age for non-lung solid-organ transplantation is associated with higher rates of rejection, graft loss and mortality. Although there have been no studies specifically examining adolescent outcomes after lung transplantation (LTx), limited data from the International Society of Heart and Lung Transplantation (ISHLT) Registry suggest that a similar association may exist. Recently, adolescence has been defined as 10 to 24 years of age, taking into account the biologic and sociologic transitions that occur during this age interval.The ISHLT Registry was used to examine the survival outcomes of LTx recipients 10 to 24 years of age between 2005 and 2013. Given the developmental changes that occur in adolescence, survival outcomes for the tertiles of adolescence (10 to 14, 15 to 19 and 20 to 24 years old) were also examined.Adolescents made up 9% (n = 2,319) of the 24,730 LTxs undertaken during the study period. Kaplan-Meier survival estimates at 3 years showed lower adolescent survival (65%) when compared with younger children (73%, p = 0.006) and adults 25 to 34 (75%, p0.00001) and 35 to 49 (71%, p0.00001) years of age, without a significant survival difference compared with those 50 to 65 years old. Critically, 15- to 19-year-old recipients had the poorest outcomes, with reduced 1-year survival (82%) compared with those 10 to 14 years old (88%, p = 0.02), and reduced 3-year survival (59%) compared with those 10 to 14 (73%, p0.00001) and 20 to 24 (66%, p0.0001) years old.Adolescent LTx recipients have poorer overall survival when compared with younger children and adults, with those 15 to 19 years old having the highest risk of death. This survival disparity among age groups likely reflects the difficult period of adolescence and its biologic and social transitions, which may influence both immunologic function and adherence.

Pediatric lung transplantation has advanced over the years, providing a potential life-prolonging therapy to patients with cystic fibrosis. Despite this, many challenges in lung transplantation remain and result in worse outcomes than other solid organ transplants. As CF lung disease progresses, children and their caregivers are often simultaneously preparing for lung transplantation and end of life. In this article, we will discuss the current barriers to success in pediatric CF lung transplantation as well as approaches to end of life care in this population.

Based on reports in adult lung transplant recipients, we hypothesized that community-acquired respiratory viral infections (CARVs) would be a risk factor for poor outcome after pediatric lung transplant. We followed 61 pediatric lung transplant recipients for 2+ years or until they met a composite primary endpoint including bronchiolitis obliterans syndrome/obliterative bronchiolitis, retransplant, or death. Blood, bronchoalveolar lavage, and nasopharyngeal specimens were obtained with standard of care visits. Nasopharyngeal specimens were obtained from recipients with respiratory viral symptoms. Respiratory specimens were interrogated for respiratory viruses by using multiplex polymerase chain reaction. Donor-specific HLA antibodies, self-antigens, and ELISPOT reactivity were also evaluated. Survival was 84% (1 year) and 68% (3 years). Bronchiolitis obliterans syndrome incidence was 20% (1 year) and 38% (3 years). The primary endpoint was met in 46% of patients. CARV was detected in 156 patient visits (74% enterovirus/rhinovirus). We did not find a relationship between CARV recovery from respiratory specimens and the primary endpoint (hazard ratio 0.64 [95% confidence interval: 0.25-1.59], P = .335) or between CARV and the development of alloimmune or autoimmune humoral or cellular responses. These findings raise the possibility that the immunologic impact of CARV following pediatric lung transplant is different than that observed in adults.

Background Percutaneous lymphatic intervention (PCL) is a promising new therapy for plastic bronchitis (PB). We characterized bronchoalveolar lavage (BAL) and cast morphology in surgically repaired congenital heart disease (CHD) patients with PB during PCL. We quantified respiratory and bronchoscopic characteristics and correlated them with post-intervention respiratory outcomes. Methods We retrospectively reviewed patients with PB and surgically repaired CHD undergoing PCL and bronchoscopy at our institution. Pre-intervention characteristics, bronchoscopy notes, BAL cell counts, virology, and cultures were collected. A pathologist blinded to clinical data reviewed cast specimens. Respiratory outcomes were evaluated through standardized telephone questionnaire. Results Sixty-two patients were included with a median follow-up of 20 months. No patients experienced airway bleeding, obstruction, or prolonged intubation related to bronchoscopy. Of BAL infectious studies, the positive results were 4 (8%) fungal, 6 (11%) bacterial, and 6 (14%) viral. Median BAL count per 100 cells for neutrophils, lymphocytes, and eosinophils were 13, 10, and 0, respectively. Of 23 bronchial casts analyzed, all contained lymphocytes, and 19 (83%) were proteinaceous, with 14 containing neutrophils and/or eosinophils. Median BAL neutrophil count was greater in patients with proteinaceous neutrophilic or eosinophilic casts compared to casts without neutrophils or lymphocytes (P = 0.030). Post-intervention, there was a significant reduction in respiratory medications and support and casting frequency. Conclusions The predominance of neutrophilic proteinaceous casts and high percentage of positive BAL infectious studies support short-term fibrinolytic and anti-infective therapies in PB in select patients. Flexible bronchoscopy enables safe assessment of cast burden. PCL effectively treats PB and reduces respiratory therapies.

Stenosis of the pulmonary arteries frequently occurs during staged palliation of hypoplastic left heart syndrome and variants, often necessitating stent angioplasty. A complication of stent angioplasty is compression of the ipsilateral mainstem bronchus. Following such a case, we re-evaluated our approach to PA stent angioplasty in these patients. The incident case is described. A retrospective observational study of children and adults with superior (SCPC) and/or total cavopulmonary connection (TCPC) undergoing left pulmonary artery (LPA) stent angioplasty between January 1, 2005 and January 5, 2014 and subsequent chest CT was performed to assess the incidence of bronchial compression. The current strategy of employing bronchoscopy to assess bronchial compression during angioplasty is described with short-term results. Sixty-five children and adults underwent LPA stent angioplasty. Other than the incident case, none had symptomatic bronchial compression. Of the total study population, 12 % had subsequent CT, of which one subject had moderate bronchial compression. To date, seven subjects have undergone angioplasty of LPA stenosis and bronchoscopy. In one case, stent angioplasty was not performed because of baseline bronchial compression, exacerbated during angioplasty. In the rest of cases, mild-moderate compression was seen during angioplasty. Following stent angioplasty, the resultant compression was not worse than that seen on test angioplasty. Bronchial compression is a rare complication of stent angioplasty of the pulmonary arteries in children and adults with SCPC/TCPC. Angioplasty of the region of interest with procedural bronchoscopy can help to identify patients at risk of this complication.

Background Prospective studies to determine associated risk factors and related outcomes for pulmonary fungal infection (PFI) after pediatric lung transplant (PLT) are lacking. Methods NIH-sponsored Clinical Trials in Organ Transplantation in Children enrolled PLT candidates, collecting data prospectively for 2 years post-transplant. Demographics, signs/symptoms, radiology, pathology and microbiology were collected. Analyses evaluated for PFI-related risks and outcomes. Results In 59 PLT, pre-transplant fungal colonization occurred in 6 donors and 15 recipients. Cystic fibrosis (CF) was associated with pre-transplant colonization (P

INTRODUCTION: Transplant volume represents lung transplant (LTx) expertise and predicts outcomes, so we sought to determine outcomes related to center volumes in CF. METHODS: United Network for Organ Sharing data were queried for CF patients receiving bilateral LTx from 2005-2015. Multivariable Cox regression was used to model survival to 1 year and long-term (>1 year) survival, conditional on surviving at least 1 year. RESULTS: 2,025 patients and 67 centers were included in the analysis. The median annual LTx volumes were 3 in CF (interquartile range [IQR]: 2, 6), and 17 in non-CF (IQR: 8, 33). Multivariable Cox regression in cases with complete data and surviving at least 1 year (n=1,510) demonstrated that greater annual CF LTx volume (HR per 10 LTx=0.66; 95% CI: 0.49, 0.89; p=0.006) but not greater non-CF LTx volume (HR=1.00; 95% CI: 0.96, 1.05; p=0.844) was associated with improved long-term survival in LTx recipients with CF. A Wald interaction test confirmed that CF LTx volume was more strongly associated with long-term outcomes than non-CF LTx volume (p=0.012). Center volume was not associated with 1-year survival. CONCLUSIONS: CF-specific expertise predicted improved long-term outcomes of LTx for CF, whereas general LTx expertise was unassociated with CF patients' survival. This article is protected by copyright. All rights reserved.

In adult lung transplantation, a single minimal AR episode is a significant predictor of BOS independent of other factors. However, the significance of single minimal AR episodes in children is unknown. A retrospective, multi-center analysis was performed to determine whether isolated single AR episodes are associated with an increased BOS risk in children. Risk factors for BOS, death, or re-transplantation, and a combined outcome of BOS, death, or re-transplantation were assessed. Original data included 577 patients (

Background Cytomegalovirus (CMV) has been associated with morbidity, including chronic allograft rejection, in transplant recipients. Data from adult centers suggests that CMV hyperimmune globulin (CMVIG) and ganciclovir together are superior in preventing CMV viremia than ganciclovir alone. Methods A retrospective review of pediatric lung transplant recipients at 14 sites in North America and Europe was conducted to evaluate the effect of adding cytomegalovirus immunoglobulin (CMVIG) prophylaxis to at least 3 weeks of intravenous ganciclovir therapy in pediatric lung transplant recipients. Data were recorded for the first year after transplantation. Associations between time to CMV and risk factors, including CMVIG use, were assessed by multivariable Cox proportional hazards models. Results Of 599 patients whose records were reviewed, 329 received at least 3 weeks of ganciclovir, with 62 (19%) receiving CMVIG. CMVIG was administered more frequently with CMV donor-positive/recipient-negative serostatus ( p Conclusion The use of CMVIG in addition to antiviral prophylaxis in pediatric lung transplantation requires further evaluation.

A retrospective review of pediatric lung transplant recipients at 14 centers in North America and Europe was conducted to characterize the epidemiology and the risk factors for cytomegalovirus (CMV) and to explore the impact of preventative antiviral therapy.Data were recorded for 1 year posttransplant. Associations between CMV and continuous and categorical risk factors were assessed using Wilcoxon rank sum and chi-square tests, respectively. Associations between time to CMV and risk factors or survival were assessed by multivariable Cox proportional hazards models.Within 12 months posttransplant, 172 of 577 subjects (29.8%) developed 218 CMV episodes (90 asymptomatic infection, 25 syndrome, and 103 disease). Forty-one subjects developed more than one episode of CMV. Donor or recipient CMV seropositivity was associated with increased risk of CMV episodes. Except for decreased prophylaxis in CMV D-/R- subjects, duration of prophylaxis did not vary by D/R serostatus. For CMV D+ subjects, not being on prophylaxis at the time of CMV episode increased the risk of CMV (D+/R+ hazard ratio 3.5, 95% confidence interval 1.4-8.4; D+/R- 1.9, 1.02-3.7). CMV was associated with increased mortality within the first posttransplant year among those with donor or recipient CMV seropositivity (hazard ratio 2.0: 95% confidence interval 1.1-3.6; P=0.024).CMV remains a serious complication after pediatric lung transplant, and the impact of prophylaxis is complex.

Background—Increasing numbers of children with advanced neuroblastoma are achieving cure. We describe the clinical late effects specific to survivors of stage IV neuroblastoma all similarly treated using tandem autologous peripheral blood stem cell rescue with TBI. Method—The medical records of 35 neuroblastoma patients treated at CHOP between 1997 and 2001 were examined. Eighteen of the 35 patients died of progressive disease, and 4 were lost to follow-up. Thirteen patients continue to follow-up in our Multi-disciplinary Cancer Survivorship Clinic where they are evaluated and monitored by a consistent group of subspecialists that evaluate long-term sequelae. Data on treatment exposures including TBI and treatment related sequelae identified by clinician assessment and/or diagnostic testing were collected. Results—Results indicate late effects were present in all 13 subjects, 12 of whom suffered from multiple negative sequelae, including issues with growth hormone deficiency, dental problems, osteochondromas and hearing deficiencies, among others, most at higher rates than reported previously. Conclusions—The findings in this small cohort indicate the need for future prospective studies of this intensive pediatric cancer treatment, and underscore the importance of medical intervention and long-term monitoring of these at-risk subjects to increase overall quality-of-life.

Anecdotally, short lung transplant candidates suffer from long waiting times and higher rates of death on the waiting list compared with taller candidates.To examine the relationship between lung transplant candidate height and waiting list outcomes.We conducted a retrospective cohort study of 13,346 adults placed on the lung transplant waiting list in the United States between 2005 and 2011. Multivariable-adjusted competing risk survival models were used to examine associations between candidate height and outcomes of interest. The primary outcome was the time until lung transplantation censored at 1 year.The unadjusted rate of lung transplantation was 94.5 per 100 person-years among candidates of short stature (162 cm) and 202.0 per 100 person-years among candidates of average stature (170-176.5 cm). After controlling for potential confounders, short stature was associated with a 34% (95% confidence interval [CI], 29-39%) lower rate of transplantation compared with average stature. Short stature was also associated with a 62% (95% CI, 24-96%) higher rate of death or removal because of clinical deterioration and a 42% (95% CI, 10-85%) higher rate of respiratory failure while awaiting lung transplantation.Short stature is associated with a lower rate of lung transplantation and higher rates of death and respiratory failure while awaiting transplantation. Efforts to ameliorate this disparity could include earlier referral and listing of shorter candidates, surgical downsizing of substantially oversized allografts for shorter candidates, and/or changes to allocation policy that account for candidate height.

Background— Plastic bronchitis is a potentially fatal disorder occurring in children with single-ventricle physiology, and other diseases, as well, such as asthma. In this study, we report findings of abnormal pulmonary lymphatic flow, demonstrated by MRI lymphatic imaging, in patients with plastic bronchitis and percutaneous lymphatic intervention as a treatment for these patients. Methods and Results— This is a retrospective case series of 18 patients with surgically corrected congenital heart disease and plastic bronchitis who presented for lymphatic imaging and intervention. Lymphatic imaging included heavy T2-weighted MRI and dynamic contrast-enhanced magnetic resonance lymphangiogram. All patients underwent bilateral intranodal lymphangiogram, and most patients underwent percutaneous lymphatic intervention. In 16 of 18 patients, MRI or lymphangiogram or both demonstrated retrograde lymphatic flow from the thoracic duct toward lung parenchyma. Intranodal lymphangiogram and thoracic duct catheterization was successful in all patients. Seventeen of 18 patients underwent either lymphatic embolization procedures or thoracic duct stenting with covered stents to exclude retrograde flow into the lungs. One of the 2 patients who did not have retrograde lymphatic flow did not undergo a lymphatic interventional procedure. A total of 15 of 17(88%) patients who underwent an intervention had significant symptomatic improvement at a median follow-up of 315 days (range, 45–770 days). The most common complication observed was nonspecific transient abdominal pain and transient hypotension. Conclusions— In this study, we demonstrated abnormal pulmonary lymphatic perfusion in most patients with plastic bronchitis. Interruption of the lymphatic flow resulted in significant improvement of symptoms in these patients and, in some cases, at least temporary resolution of cast formation.

Anelloviruses are DNA viruses ubiquitously present in human blood. Due to their elevated levels in immunosuppressed patients, anellovirus levels have been proposed as a marker of immune status. We hypothesized that low anellovirus levels, reflecting relative immunocompetence, would be associated with adverse outcomes in pediatric lung transplantation. We assayed blood samples from 57 patients in a multicenter study for alpha- and betatorquevirus, two anellovirus genera. The primary short-term outcome of interest was acute rejection, and longer-term outcomes were analyzed individually and as “composite” (death, chronic rejection, or retransplant within two years). Patients with low alphatorquevirus levels at two weeks post-transplantation were more likely to develop acute rejection within three months after transplant (p=0.013). Low betatorquevirus levels at six weeks and six months after transplant were associated with death (p=0.047) and the composite outcome (p=0.017), respectively. There was an association between low anellovirus levels and adverse outcomes in pediatric lung transplantation. Alphatorquevirus levels were associated with short-term outcomes (i.e., acute rejection) while betatorquevirus levels were associated with longer-term outcomes (i.e., death, or composite outcome within two years). These observations suggest that anelloviruses may serve as useful biomarkers of immune status and predictors of adverse outcomes.

Bilateral lung transplantation remains a treatment for end-stage cystic fibrosis (CF) lung disease when there is no further medical or surgical treatment available. The aim of lung transplantation is to improve patient life expectancy. The consensus view that lung transplantation extends life in children has been challenged. However, challengers have faced alternative explanations of their finding and it is largely accepted that lung transplantation in the adolescent patient population is an important treatment modality. The goal of this article is to address these concerns and assist with developing creative approaches to this known challenging subset of patients. The main focus of this article will be to discuss the looming question: what existing evidence or best practice insights could improve bilateral lung transplantation outcomes for adolescent patients with end-stage CF?

Background The use of induction immunosuppressive agents in pediatric lung transplantation is not universal. The rationale of induction therapy is to use the strongest immunosuppressive drugs at the time when the risk of acute cellular rejection (ACR) is highest. The timing of induction is not universal. We hypothesize that early treatment with antilymphocyte globulin (ATG) prior to reperfusion of the first donor lung will decrease the incidence of ACR. Methods The initial dose of ATG was given during the operative procedure when the recipient was on cardiopulmonary bypass after removal of the recipient lungs and prior to implantation. Patients received additional doses daily for four days. All children were monitored for ACR during the first 6 months posttransplant with transbronchial biopsies at defined intervals (weeks-months) and when clinically indicated. Presence of ACR was defined by International Society for Heart & Lung Transplantation guidelines. Results Recipients from two pediatric centers received ATG based on this protocol. A total of 18 patients were treated with this protocol, and the follow-up period was 6 to 45 months. A total of 63 flexible bronchoscopies with transbronchial biopsies were performed during the first 6 months. A single episode of ACR (≥ grade A2) was identified in this patient population for an incidence of 5.2% ACR grade A2 or above in this patient population. Conclusions Induction therapy with ATG prior to donor lung reperfusion is associated with a low incident of ACR during the first 6 months posttransplant in our patient cohort. Long-term follow-up is needed to ascertain the full effect of this treatment protocol.

To characterize epidemiology and risk factors for respiratory viral infections (RVI) in pediatric lung transplant recipients within the first post‐transplant year, a retrospective multicenter study of pediatric lung transplant recipients from 1988 to 2005 was conducted at 14 centers in the United States and Europe. Data were recorded for 1 year post transplant. Associations between RVI and continuous and categorical risk factors were assessed using Wilcoxon's rank‐sum and χ2 tests, respectively. Associations between time to RVI and risk factors or survival were assessed by multivariable Cox proportional hazards models. Of 576 subjects, 79 subjects (14%) had 101 RVI in the first year post transplant. Subjects with RVI were younger than those without RVI (median ages 9.7, 13; P

Risk factors, morbidity and mortality from pulmonary fungal infections (PFIs) within the first year after pediatric lung transplant have not previously been characterized.A retrospective, multicenter study from 1988 to 2005 was conducted with institutional approval from the 12 participating centers in North America and Europe. Data were recorded for the first post-transplant year. The log-rank test assessed for the association between PFI and survival. Associations between time to PFI and risk factors were assessed by Cox proportional hazards models.Of the 555 subjects transplanted, 58 (10.5%) had 62 proven (Candida, Aspergillus or other) or probable (Aspergillus or other) PFIs within the first year post-transplant. The mean age for PFI subjects was 14.0 years vs 11.4 years for non-PFI subjects (p0.01). Candida and Aspergillus species were recovered equally for proven disease. Comparing subjects with PFI (n = 58) vs those without (n = 404), pre-transplant colonization was associated with PFI (hazard ratio [HR] 2.0; 95% CI 0.95 to 4.3, p = 0.067). Cytomegalovirus (CMV) mismatch, tacrolimus-based regimen and age15 years were associated with PFI (p0.05). PFI was associated with any prior rejection higher than Grade A2 (HR 2.1; 95% CI 1.2 to 3.6). Cystic fibrosis, induction therapy, transplant era and type of transplant were not associated with PFI. PFI was independently associated with decreased 12-month survival (HR 3.9, 95% CI 2.2 to 6.8).Risk factors for PFI include Grade A2 rejection, repeated acute rejection, CMV-positive donor, tacrolimus-based regimen and pre-transplant colonization.

The members of the cytoplasmic 70-kDa heat shock protein family are involved in appropriate folding and trafficking of newly synthesized proteins in the cell. Hsc70, which is expressed constitutively, and Hsp70, the expression of which is stress- and heat shock-induced, are often considered to have similar cellular functions in this regard, but there are suggestions that the intracellular functions of these homologous but not identical proteins may differ. We tested the hypothesis that Hsc70 and Hsp70 would have differential effects on the expression of the epithelial sodium channel (ENaC). In Xenopus oocytes, overexpression of human Hsc70 decreased the functional (defined as amiloride-sensitive whole-oocyte current) and surface expression of murine ENaC (mENaC) in a concentration-dependent fashion. In contrast, coinjection of a moderate amount of Hsp70 cRNA (10 ng) increased the functional and surface expression of mENaC, whereas a higher amount of coinjected Hsp70 cRNA (30 ng) decreased mENaC functional and surface expression. The increase in mENaC functional expression with coinjection of 10 ng of Hsp70 cRNA was antagonized by the additional coinjection of Hsc70 cRNA in a concentration-dependent fashion. These data are consistent with Hsc70 and Hsp70 having differential and antagonistic effects with regard to the intracellular trafficking of mENaC in oocytes, which may have an impact on our understanding and potential treatment of diseases of aberrant ion channel trafficking.