Implementation and Feasibility of Clinical Genome Sequencing Embedded Into the Outpatient Nephrology Care for Patients With Proteinuric Kidney Disease.

Introduction: The diagnosis and management of proteinuric kidney diseases such as focal segmental glomerulosclerosis (FSGS) are challenging. Genetics holds the promise to improve clinical decision making for these diseases; however, it is often performed too late to enable timely clinical action and it is not implemented within routine outpatient nephrology visits. Methods: We sought to test the implementation and feasibility of clinical rapid genome sequencing (GS) in guiding decision making in patients with proteinuric kidney disease in real-time and embedded in the outpatient nephrology setting. Results: We enrolled 10 children or young adults with biopsy-proven FSGS (9 cases) or minimal change disease (1 case). The mean age at enrollment was 16.2 years (range 2-30). The workflow did not require referral to external genetics clinics but was conducted entirely during the nephrology standard-of-care appointments. The total turn-around-time from enrollment to return-of-results and clinical decision averaged 21.8 days (12.4 for GS), which is well within a time frame that allows clinically relevant treatment decisions. A monogenic or APOL1-related form of kidney disease was diagnosed in 5 of 10 patients. The genetic findings resulted in a rectified diagnosis in 6 patients. Both positive and negative GS findings determined a change in pharmacological treatment. In 3 patients, the results were instrumental for transplant evaluation, donor selection, and the immunosuppressive treatment. All patients and families received genetic counseling. Conclusion: Clinical GS is feasible and can be implemented in real-time in the outpatient care to help guiding clinical management. Additional studies are needed to confirm the cost-effectiveness and broader utility of clinical GS across the phenotypic and demographic spectrum of kidney diseases.

Rare Single Nucleotide and Copy Number Variants and the Etiology of Congenital Obstructive Uropathy: Implications for Genetic Diagnosis.

SIGNIFICANCE STATEMENT: Congenital obstructive uropathy (COU) is a prevalent human developmental defect with highly heterogeneous clinical presentations and outcomes. Genetics may refine diagnosis, prognosis, and treatment, but the genomic architecture of COU is largely unknown. Comprehensive genomic screening study of 733 cases with three distinct COU subphenotypes revealed disease etiology in 10.0% of them. We detected no significant differences in the overall diagnostic yield among COU subphenotypes, with characteristic variable expressivity of several mutant genes. Our findings therefore may legitimize a genetic first diagnostic approach for COU, especially when burdening clinical and imaging characterization is not complete or available. BACKGROUND: Congenital obstructive uropathy (COU) is a common cause of developmental defects of the urinary tract, with heterogeneous clinical presentation and outcome. Genetic analysis has the potential to elucidate the underlying diagnosis and help risk stratification. METHODS: We performed a comprehensive genomic screen of 733 independent COU cases, which consisted of individuals with ureteropelvic junction obstruction ( n =321), ureterovesical junction obstruction/congenital megaureter ( n =178), and COU not otherwise specified (COU-NOS; n =234). RESULTS: We identified pathogenic single nucleotide variants (SNVs) in 53 (7.2%) cases and genomic disorders (GDs) in 23 (3.1%) cases. We detected no significant differences in the overall diagnostic yield between COU sub-phenotypes, and pathogenic SNVs in several genes were associated to any of the three categories. Hence, although COU may appear phenotypically heterogeneous, COU phenotypes are likely to share common molecular bases. On the other hand, mutations in TNXB were more often identified in COU-NOS cases, demonstrating the diagnostic challenge in discriminating COU from hydronephrosis secondary to vesicoureteral reflux, particularly when diagnostic imaging is incomplete. Pathogenic SNVs in only six genes were found in more than one individual, supporting high genetic heterogeneity. Finally, convergence between data on SNVs and GDs suggest MYH11 as a dosage-sensitive gene possibly correlating with severity of COU. CONCLUSIONS: We established a genomic diagnosis in 10.0% of COU individuals. The findings underscore the urgent need to identify novel genetic susceptibility factors to COU to better define the natural history of the remaining 90% of cases without a molecular diagnosis.

Human stem cell-derived thymic epithelial cells enhance human T-cell development in a xenogeneic thymus.

BACKGROUND: Generation of thymic tissue from pluripotent stem cells would provide therapies for acquired and congenital thymic insufficiency states. OBJECTIVES: This study aimed to generate human thymic epithelial progenitors from human embryonic stem cells (hES-TEPs) and to assess their thymopoietic function in vivo. METHODS: This study differentiated hES-TEPs by mimicking developmental queues with FGF8, retinoic acid, SHH, Noggin, and BMP4. Their function was assessed in reaggregate cellular grafts under the kidney capsule and in hybrid thymi by incorporating them into swine thymus (SwTHY) grafts implanted under the kidney capsules of immunodeficient mice that received human hematopoietic stem and progenitor cells (hHSPCs) intravenously. RESULTS: Cultured hES-TEPs expressed FOXN1 and formed colonies expressing EPCAM and both cortical and medullary thymic epithelial cell markers. In thymectomized immunodeficient mice receiving hHSPCs, hES-TEPs mixed with human thymic mesenchymal cells supported human T-cell development. Hypothesizing that support from non-epithelial thymic cells might allow long-term function of hES-TEPs, the investigators injected them into SwTHY tissue, which supports human thymopoiesis in NOD severe combined immunodeficiency IL2Rγnull mice receiving hHSPCs. hES-TEPs integrated into SwTHY grafts, enhanced human thymopoiesis, and increased peripheral CD4+ naive T-cell reconstitution. CONCLUSIONS: This study has developed and demonstrated in vivo thymopoietic function of hES-TEPs generated with a novel differentiation protocol. The SwTHY hybrid thymus model demonstrates beneficial effects on human thymocyte development of hES-TEPs maturing in the context of a supportive thymic structure.

Racial-ethnic differences in health-related quality of life among adults and children with glomerular disease.

INTRODUCTION: Disparities in health-related quality of life (HRQOL) have been inadequately studied in patients with glomerular disease. The aim of this study was to identify relationships between race/ethnicity, socioeconomic status, disease severity, and HRQOL in an ethnically and racially diverse cohort of patients with glomerular disease. METHODS: Cure Glomerulonephropathy (CureGN) is a multinational cohort study of patients with biopsy-proven glomerular disease. Associations between race/ethnicity and HRQOL were determined by the following: 1. Missed school or work due to kidney disease; 2. Responses to Patient Reported Outcomes Measurement Information System (PROMIS) questionnaires. We adjusted for demographics, socioeconomic status, and disease characteristics using multivariable logistic and linear regression. RESULTS: Black and Hispanic participants had worse socioeconomic status and more severe glomerular disease than White or Asian participants. Black adults missed work or school most frequently due to kidney disease (30% versus 16-23% in the other three groups, p=0.04), and had the worst self-reported global physical health (median score 44.1 versus 48.0-48.2, p<0.001) and fatigue (53.8 versus 48.5-51.1, p=0.002), compared to other racial/ethnic groups. However, these findings were not statistically significant with adjustment for socioeconomic status and disease severity, both of which were strongly associated with HRQOL in adults. Among children, disease severity but not race/ethnicity or socioeconomic status were associated with HRQOL. CONCLUSIONS: Among patients with glomerular disease enrolled in CureGN, the worse HRQOL reported by Black adults was attributable to lower socioeconomic status and more severe glomerular disease. No racial/ethnic differences in HRQOL were observed in children.

GeneLiFT: A novel test to facilitate rapid screening of genetic literacy in a diverse population undergoing genetic testing.

With the broader introduction of genomic medicine in research and clinical care, an increasing number of persons are offered genetic testing. Many factors, including genetic literacy, may impact the utilization of genetic results by patients and their families. We developed a rapid, self-administered measure of genetic literacy, called Genetic Literacy Fast Test (GeneLiFT). We next evaluated the association of GeneLiFT scores with the comprehension of limitations of genomic medicine in participants undergoing genetic testing in the NIH-sponsored eMERGE III study at Columbia University Irving Medical Center, New York. All participants underwent genetic screening for variants in 74 actionable genes associated with adult-onset disorders. A diverse cohort of 724 participants completed the survey (60% women, 45% less than 40 years old, and 53% self-reported White non-Hispanic ancestry). The GeneLiFT was validated using known group differences based on education, health literacy, and numeracy, and with questions assessing genetic knowledge. GeneLiFT identified multiple standard genetics terms, that is, jargon, not recognized by more than 50% of participants (including actionability and pathogenicity). Low genetic literacy, identified in 210 participants (29%), was significantly associated with poor understanding of the limitations of genetic testing (p-values < 10-9 ). This association was independent of education, health literacy, and numeracy levels, highlighting the importance of directly measuring genetic literacy. Low genetic literacy was also associated with low satisfaction with the informed consent process. GeneLiFT is a practical tool for rapid assessment of genetic literacy in large studies or clinical care. GeneLiFT will allow future research to efficiently assess the role of genetic literacy on the clinical impact of genetic testing.

Overall survival analysis in patients with metastatic breast cancer and liver or lung metastases treated with eribulin, gemcitabine, or capecitabine.

PURPOSE: The purpose of this study was to estimate the overall survival (OS) in real-world clinical practice in patients with metastatic breast cancer (MBC) and visceral metastases (liver or lung) treated in the third-line setting with eribulin, gemcitabine or capecitabine overall and in the major clinical categories of MBC (TNBC, HR+/HER2-, and HER2+). METHODS: A retrospective, observational study was conducted with de-identified patient electronic health records from the Cancer Treatment Centers of America (CTCA). Patients with a diagnosis of metastatic breast with lung or liver metastases, and treated with eribulin, gemcitabine, or capecitabine as third-line therapy were included in the analysis. Landmark survival was calculated as percentage of patients alive at 6, 12, 24, and 36 months. Overall survival was compared between treatment arms within TNBC and HR+/HER2- using log-rank analysis. Cox regression analyses was performed to estimate hazard ratios for comparison of treatments within TNBC and HR+/HER2- subtype. RESULTS: 443 patients with liver or lung metastases received third-line therapy with eribulin (n = 229), gemcitabine (n = 134), or capecitabine (n = 80). Eribulin patients had a higher percentage of patients alive at all landmark timepoints vs. gemcitabine, and a higher percentage of patients alive until 36 months vs. capecitabine. Median survival times showed that overall, and within the TNBC and HR+/HER2- subtype, patients receiving eribulin had a numerically higher median overall survival. CONCLUSIONS: This real-world evidence study is consistent with randomized clinical trial data and demonstrates consistency of eribulin effectiveness in MBC patients with lung or liver metastases overall and in TNBC and HR+/HER2- disease.

Persistent Disease Activity in Patients With Long-Standing Glomerular Disease.

INTRODUCTION: Glomerular diseases are characterized by variable disease activity over many years. We aimed to analyze the relationship between clinical disease activity and duration of glomerular disease. METHODS: Disease activity in adults with chronic minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, and IgA nephropathy (IgAN; first diagnostic biopsy >5 years before enrollment; Of Longstanding Disease [OLD] cohort, n = 256) followed at Columbia University Medical Center (CUMC), was compared with disease activity of an internal and external cohort of patients with first diagnostic biopsy <5 years before enrollment drawn from the Cure Glomerulonephropathy Network (CureGN cohort, n = 1182; CUMC-CureGN cohort, n = 362). Disease activity was defined by (i) Kidney Disease: Improving Global Outcomes-recommended threshold criteria for initiation of immunosuppression in primary glomerulonephropathy (GN) and (ii) CureGN's Disease Activity Working Group definitions for activity. RESULTS: No significant differences were detected among the 3 cohorts in terms of age, sex, serum creatinine, and urinary protein-to-creatinine ratio. For each GN subtype, disease activity in the OLD cohort was comparable with disease activity in the entire CureGN and the CUMC-CureGN cohort. When limiting our comparisons to disease activity in incident CUMC-CureGN patients (first diagnostic biopsy within 6 months of enrollment), OLD patients demonstrated similar activity rates as incident patients. CONCLUSION: Disease activity did not differ among patients with shorter versus longer duration of disease. Such survivor patients, with long-term but persistent disease, are potentially highly informative for understanding the clinical course and pathogenesis of GN and may help identify factors mediating more chronic subtypes of disease.

Lenvatinib and Subsequent Therapy for Radioactive Iodine-Refractory Differentiated Thyroid Cancer: A Real-World Study of Clinical Effectiveness in the United States.

INTRODUCTION: Lenvatinib has become the most commonly prescribed first-line (1L) agent for the treatment of radioactive iodine-refractory differentiated thyroid cancer (RAI-r DTC) since its approval in 2015. With no real-world studies describing clinical outcomes of 1L lenvatinib and subsequent therapy, the current study aimed to assess treatment sequencing and related clinical outcomes in patients treated with 1L lenvatinib in the USA METHODS: We conducted a multisite, retrospective chart review of US patients with a diagnosis of RAI-r DTC who had initiated 1L therapy with lenvatinib from January 1, 2016 through May 31, 2017 with follow-up through October 17, 2018. Physicians completed electronic case report forms for two patient cohorts: patients still receiving 1L lenvatinib (cohort 1) and those who had initiated second-line (2L) therapy prior to data cutoff (cohort 2). Real-world objective response rate (ORR) was assessed for both cohorts. Progression-free survival (PFS) and overall survival (OS) were assessed for cohort 2. RESULTS: A total of 252 patients met the study criteria with 71 in cohort 1 and 181 in cohort 2. Patients were predominantly female, had papillary DTC, and had lung metastases. The ORR was 64.8% for cohort 1 and 53.6% for cohort 2. In cohort 2, median PFS from 1L lenvatinib initiation was 14.0 months (95% CI 12.7-15.0). Second-line treatments included sorafenib (49.7%), cabozantinib (19.3%), and other targeted/chemotherapy/immuno-oncology agents. The ORR in 2L therapy was 15.5%. For cohort 2, the 12-, 18-, and 24-month OS from initiation of 1L lenvatinib was 92.8%, 81.5%, and 66.9%, respectively. CONCLUSIONS: In this first real-world examination of clinical effectiveness of 1L lenvatinib and subsequent therapy among patients in the US, the results demonstrated that treatment with 1L lenvatinib followed by another 2L therapy may deliver a clinical benefit, thus allowing a number of potential 2L options following 1L lenvatinib for patients with RAI-r DTC.

Observational study of clinical outcomes of eribulin mesylate in metastatic breast cancer after cyclin-dependent kinase 4/6 inhibitor therapy.

Aim: To examine the effectiveness of eribulin mesylate for metastatic breast cancer post cyclin-dependent kinase inhibitor (CDKi) 4/6 therapy. Materials & methods: US community oncologists reviewed charts of patients who had received eribulin from 3 February 2015 to 31 December 2017 after prior CDKi 4/6 therapy and detailed their clinical/treatment history, clinical outcomes (lesion measurements, progression, death) and toxicity. Results: Four patient cohorts were created according to eribulin line of therapy: second line, third line, per US label and fourth line with objective response rates/clinical benefit rates of 42.2%/58.7%, 26.1%/42.3%, 26.7%/54.1% and 17.9%/46.4%, respectively. Median progression-free survival/6-month progression-free survival (79.5% of all patients censored) by cohort was: 9.7 months/77.3%, 10.3 months/71.3%, not reached/70.4% and 4.0 months/0.0%, respectively. Overall occurrence of neutropenia = 23.5%, febrile neutropenia = 1.3%, peripheral neuropathy = 10.1% and diarrhea = 11.1%. Conclusion: Clinical outcome and adverse event rates were similar to those in clinical trials and other observational studies. Longer follow-up is required to confirm these findings.

Correction: Evaluation of the cost and effectiveness of diverse recruitment methods for a genetic screening study.

The original version of this Article contained an error in the undergraduate degree awarded to the author Ian Halim, which was incorrectly given as BS. This has now been corrected to BA in both the PDF and HTML versions of the Article.

Evaluation of the cost and effectiveness of diverse recruitment methods for a genetic screening study.

PURPOSE: Recruitment of participants from diverse backgrounds is crucial to the generalizability of genetic research, but has proven challenging. We retrospectively evaluated recruitment methods used for a study on return of genetic results. METHODS: The costs of study design, development, and participant enrollment were calculated, and the characteristics of the participants enrolled through the seven recruitment methods were examined. RESULTS: A total of 1118 participants provided consent, a blood sample, and questionnaire data. The estimated cost across recruitment methods ranged from $579 to $1666 per participant and required a large recruitment team. Recruitment methods using flyers and staff networks were the most cost-efficient and resulted in the highest completion rate. Targeted sampling that emphasized the importance of Latino/a participation, utilization of translated materials, and in-person recruitments contributed to enrolling a demographically diverse sample. CONCLUSIONS: Although all methods were deployed in the same hospital or neighborhood and shared the same staff, each recruitment method was different in terms of cost and characteristics of the enrolled participants, suggesting the importance of carefully choosing the recruitment methods based on the desired composition of the final study sample. This analysis provides information about the effectiveness and cost of different methods to recruit adults for genetic research.

Real-World Treatment Patterns Among Patients Initiating Small Molecule Kinase Inhibitor Therapies for Thyroid Cancer in the United States.

INTRODUCTION: Little is known about real-world use of small molecule kinase inhibitors (SMKI) for advanced thyroid cancer in the United States. This study examined prescribing patterns of SMKI agents recommended by the National Comprehensive Cancer Center (NCCN). METHODS: This retrospective study used a national health insurance database to identify patients diagnosed with thyroid cancer during 1/1/2006-6/30/2016 and with prescription claims for NCCN-recommended SMKI during 1/1/2010-5/31/2016 whose first claim date was the index date. Inclusion also required continuous enrollment in a health plan for 3 months pre-index (baseline) and ≥ 1 month post-index (follow-up) with no claims for SMKI during baseline. Lines of therapy (LOT) were defined by the date of SMKI claims and days of drug supply. Median time to SMKI discontinuation in each LOT was estimated by Kaplan-Meier method. RESULTS: The study included 217 patients. During follow-up (mean duration 499.0 days), 35.5% of patients (n = 77) received a second or later LOT; among patients with ≥ 12 months follow-up after first LOT (LOT1) initiation, 53.1% (n = 60) received a second or later LOT. Median treatment duration was 5.0 months for LOT1 and 5.1 months for LOT2. Over the entire follow-up period (2010-2016), sorafenib was the most common regimen in LOT1 (36.9% of patients) and LOT2 (24.7%) followed by sunitinib and levantinib (13.4% each) in LOT1 and sunitinib (19.5%) in LOT2. Starting in 2015, the year lenvatinib was approved for differentiated thyroid cancer, lenvatinib was the most common first-line regimen among patients initiating LOT1 in 2015 (43.4%) and 2016 (66.7%). CONCLUSION: Sorafenib was the most common first-line agent during 2010-2014 but was supplanted by lenvatinib starting in 2015. Approximately 36-53% of patients received a second-line treatment. Median treatment duration results suggested potential benefit of SMKI in second-line therapy. SMKI treatment after first-line failure may be considered for appropriately selected patients. FUNDING: Eisai, Inc. (Woodcliff Lake, NJ).

Diagnostic Utility of Exome Sequencing for Kidney Disease.

BACKGROUND: Exome sequencing is emerging as a first-line diagnostic method in some clinical disciplines, but its usefulness has yet to be examined for most constitutional disorders in adults, including chronic kidney disease, which affects more than 1 in 10 persons globally. METHODS: We conducted exome sequencing and diagnostic analysis in two cohorts totaling 3315 patients with chronic kidney disease. We assessed the diagnostic yield and, among the patients for whom detailed clinical data were available, the clinical implications of diagnostic and other medically relevant findings. RESULTS: In all, 3037 patients (91.6%) were over 21 years of age, and 1179 (35.6%) were of self-identified non-European ancestry. We detected diagnostic variants in 307 of the 3315 patients (9.3%), encompassing 66 different monogenic disorders. Of the disorders detected, 39 (59%) were found in only a single patient. Diagnostic variants were detected across all clinically defined categories, including congenital or cystic renal disease (127 of 531 patients [23.9%]) and nephropathy of unknown origin (48 of 281 patients [17.1%]). Of the 2187 patients assessed, 34 (1.6%) had genetic findings for medically actionable disorders that, although unrelated to their nephropathy, would also lead to subspecialty referral and inform renal management. CONCLUSIONS: Exome sequencing in a combined cohort of more than 3000 patients with chronic kidney disease yielded a genetic diagnosis in just under 10% of cases. (Funded by the National Institutes of Health and others.).

Adolescent Connectedness with Parents Promotes Resilience among Homeless Youth.

Youth who experience homelessness have worse health and well-being than housed youth. Internal assets, including social competency and positive self-identity, are factors that promote healthy development. This study compared internal assets between homeless and housed youth, and examined whether connectedness with parents moderates the association between homelessness and internal assets. Using data from a large population-based survey of middle- and high-school aged youth, we found that homelessness was associated with lower levels of internal assets. However, having high connectedness with a parent significantly predicted the strength of these assets, suggesting opportunities to promote health equity among homeless youth.

Emotional Health Among Youth Experiencing Family Homelessness.

BACKGROUND AND OBJECTIVES: Youth who are homeless with adult family members comprise 37% of the US homeless population, yet mental health among this group has not yet been well described. We aimed to compare the risk of suicidality, and factors that may protect against it, between family-homeless and nonhomeless youth. METHODS: We used cross-sectional data, representing 62 034 eighth- to 12th-graders, to estimate the adjusted odds ratio (aOR) of emotional distress, self-injury, suicidal ideation, and attempted suicide in the past 12 months for youth who experienced family homelessness in the past 12 months compared with housed youth, controlling for covariates. We then tested whether developmental assets moderated these outcomes. RESULTS: Four percent (n = 4594) of youth (mean age 14.9 years) were homeless with an adult family member. Among these, 29.1% (n = 1317; aOR: 2.52, 95% confidence interval [CI] 2.34-2.69) reported self-injury, 21% (n = 940; aOR: 2.30, 95% CI: 2.14-2.48) reported suicidal ideation, and 9.3% (n = 416; aOR: 3.24, 95% CI: 2.91-3.60) reported suicide attempts. Developmental assets decreased the odds of these outcomes for all youth but were less protective for homeless youth. CONCLUSIONS: Youth experiencing recent family homelessness are at higher risk of suicidality than their nonhomeless peers, suggesting homelessness itself as a marker of risk. Factors that protect emotional health are less impactful among youth experiencing recent family homelessness. Thus, interventions among homeless youth may need to address social determinants of health such as stable housing and adversity in addition to developmental assets.

Adverse Childhood Experiences and Early Initiation of Marijuana and Alcohol Use: The Potential Moderating Effects of Internal Assets.

INTRODUCTION: Early adolescence is a critical risk period for initiation of substance use. Internal assets (IAs), which are individual qualities guiding positive choices, and adverse childhood experiences (ACEs) are important protective and risk factors, respectively, against substance use. The purpose of this study is to investigate whether IAs modify associations between ACEs and early initiation of alcohol and marijuana use. METHOD: Data were from 9th and 11th graders who completed the 2013 Minnesota Student Survey (n = 79,339). Students reported on experiences of abuse, household dysfunction, and substance use. Multivariable logistic regressions examined associations between different types of ACEs and substance use. Interactions between IAs and ACEs were added to models to test effect modification. For significant interactions, main effects models were re-estimated at different percentiles of IAs. RESULT: IAs moderated associations of both abuse and household dysfunction with early initiation of marijuana (p <.003) and alcohol (p =.007) for females but not for males. For females with low IAs, odds of early initiation of marijuana were approximately twice as high as students without any ACEs. A similar pattern was detected for females' initiation of alcohol use. No effect modification was detected for IAs and experiencing only abuse or household dysfunction on initiation. CONCLUSION: Special attention should be paid to improving IAs among girls who have already experienced ACEs. Future research should examine protective factors that buffer the effects of ACEs for boys.

Prevalence of polyreactive innate clones among graft--infiltrating B cells in human cardiac allograft vasculopathy.

BACKGROUND: Cardiac allograft vasculopathy (CAV) has been associated with graft-infiltrating B cells, although their characteristics are still unclear. In this study we examined the frequency, localization and reactivity profile of graft-infiltrating B cells to determine their contribution to the pathophysiology of CAV. METHODS: B cells, plasma cells and macrophages were examined by immunohistochemistry in 56 allografts with CAV, 49 native failed hearts and 25 autopsy specimens. A total of 102 B-cell clones were immortalized directly from the infiltrates of 3 fresh cardiac samples with CAV. Their secreted antibodies were assessed using enzyme-linked immunoassay and flow cytometry. RESULTS: B-cell infiltration was observed around coronary arteries in 93% of allograft explants with CAV. Comparatively, intragraft B cells were less frequent and less dense in the intraventricular myocardium from where routine biopsies are obtained. Plasma cells and macrophages were also detected in 85% and 95% of explants, respectively. Remarkably, B-cell infiltrates were not associated with circulating donor-specific antibodies (DSA) or prior episodes of antibody-mediated rejection (AMR). Among all B-cell clones generated from 3 explants with CAV, a majority secreted natural antibodies reactive to multiple autoantigens and apoptotic cells, a characteristic of innate B cells. CONCLUSIONS: Our study reveals a high frequency of infiltrating B cells around the coronary arteries of allografts with CAV, independent of DSA or AMR. These cells are enriched for innate B cells with a polyreactive profile. The findings shift the focus from conventional DSA-producing B cells to the potentially pathogenic polyreactive B cells in the development of clinical CAV.

Ventricular assist device elicits serum natural IgG that correlates with the development of primary graft dysfunction following heart transplantation.

BACKGROUND: Pre-transplant sensitization is a limiting factor in solid-organ transplantation. In heart transplants, ventricular assist device (VAD) implantation has been associated with sensitization to human leukocyte antigens (HLA). The effect of VAD on non-HLA antibodies is unclear. We have previously shown that polyreactive natural antibodies (Nabs) contribute to pre-sensitization in kidney allograft recipients. Here we assessed generation of Nabs after VAD implantation in pre-transplant sera and examined their contribution to cardiac allograft outcome. METHODS: IgM and IgG Nabs were tested in pre-transplant serum samples collected from 206 orthotopic heart transplant recipients, including 128 patients with VAD (VAD patients) and 78 patients without VAD (no-VAD patients). Nabs were assessed by testing serum reactivity to apoptotic cells by flow cytometry and to the generic oxidized epitope, malondialdehyde, by enzyme-linked immunosorbent assay. RESULTS: No difference was observed in serum levels of IgM Nabs between VAD and no-VAD patients. However, serum IgG Nabs levels were significantly increased in VAD compared with no-VAD patients. This increase was likely due to the presence of the VAD, as revealed by lower serum IgG Nabs levels before implantation. Elevated pre-transplant IgG Nabs level was associated with development of primary graft dysfunction (PGD). CONCLUSIONS: Our study demonstrates that VAD support elicits IgG Nabs reactive to apoptotic cells and oxidized epitopes. These findings further support broad and non-specific B-cell activation by VAD, resulting in IgG sensitization. Moreover, the association of serum IgG Nabs levels with development of PGD suggests a possible role for these antibodies in the inflammatory reaction accompanying this complication.

IL-1ß limits the extent of human 6-sulfo LacNAc dendritic cell (slanDC)-mediated NK cell activation and regulates CD95-induced apoptosis.

To function optimally, human blood natural killer (NK) cells need to communicate with other immune cells. Previously, it has been shown that NK cells communicate with 6-sulfo LacNAc dendritic cells (slanDCs), which are able to stimulate NK cells in vitro. In this study, we investigated how slanDCs regulate the level of NK cell activation. The secretion of interleukin (IL)-1ß by slanDCs during coculture with NK cells increased as a result of signaling via intercellular adhesion molecule-1 on slanDCs following its interaction with lymphocyte function-associated antigen-1 on NK cells. IL-1ß induced the expression of Fas receptor (CD95) on NK cells. The binding of Fas ligand (CD178) to CD95 induced the apoptosis of activated NK cells. Moreover, IL-1ß also induced increased cyclooxygenase-2 expression in slanDCs, which in turn enabled the cells to secrete prostaglandin (PG)-E2. Consequently, PGE2 acted as a suppressing agent, tuning down the activation level of NK cells. In summary, IL-1ß limits the level of NK cell activation by inducing apoptosis and suppression as a homeostatic regulatory function.