Faculty Bibliography

BACKGROUND:Pathogenic variants in AGO2, encoding a central component of the RNA-induced silencing complex (RISC), cause the neurodevelopmental disorder Lessel-Kreienkamp syndrome (LESKRES). The variant spectrum and associated molecular mechanisms underlying phenotypic variability and disease severity remain incompletely understood. METHODS:We investigated 45 newly identified individuals carrying 33 distinct AGO2 variants, 30 of which were previously unreported. Phenotypic data from these and previously reported cases (n = 70) were integrated to delineate the LESKRES-associated clinical spectrum and genotype-phenotype correlations. Functional studies included shRNA-based silencing, co-immunoprecipitation, subcellular localization, and sequencing of AGO2-bound miRNAs. RESULTS:All individuals presented with a neurodevelopmental disorder of variable severity. Delayed speech and language development (97%), intellectual disability (97%), and motor delay (93%) were the most consistent features, frequently accompanied by muscular hypotonia, autistic traits, attention deficit hyperactivity disorder, visual impairment and structural brain anomalies. Systemic manifestations, including skeletal, craniofacial, cardiac, and male urogenital anomalies were common, underscoring AGO2's multisystemic role. Moreover, we report occurrence of gonadal mosaicism and reveal the presence of interfamilial and variant-specific clinical heterogeneity. Variants clustered in defined regions of AGO2, including the L1 loop, helix-7, and multiple loops of the PIWI domain, highlight structural hotspots critical for RISC activity. Not all pathogenic variants impaired shRNA-mediated silencing; this was restricted to p.(Arg714Trp) and p.(Asn729His). Biochemical analyses revealed that p.(Asp619Asn) impaired GW182 binding and P-body assembly. Variants p.(Arg506Gln), p.(Glu531Gln) p.(Gly604Arg) and p.(Asp619Asn), reduced C-terminal phosphorylation, implicating defective AGO2 recycling. AGO2-miRNA co-immunoprecipitation and sequencing demonstrated variant-specific perturbations in miRNA association, strand selectivity, and isomiR generation. Variants near the hinge of the helix-7 region, especially p.(Phe182del), induced extensive changes in miRNA association and 3'-end modification, suggesting impaired anchoring within the miRNA-binding pocket. CONCLUSIONS:Our findings substantially broaden the clinical and molecular landscape of LESKRES, establishing AGO2 as a pivotal regulator of neurodevelopment whose structural integrity is essential for precise miRNA-mediated gene regulation. Pathogenic variants disrupt distinct interconnected processes: P-body association, phosphorylation-dependent turnover, and miRNA interactions, culminating in dysregulated post-transcriptional gene silencing. These mechanistic insights link specific structural perturbations in AGO2 to graded clinical outcomes and underscore the critical role of AGO2 conformational dynamics in human neurodevelopment.

BACKGROUND/UNASSIGNED:Asbestosis is a progressive interstitial lung disease caused by inhalation of asbestos fibres. Although asbestos use was banned in the Netherlands in 1993, new cases continue to be diagnosed. Since 2014, a national compensation system has enabled systematic assessment of asbestosis incidence and outcomes. This population-based study examined national trends in asbestosis incidence from 2014-2024 and evaluated survival and prognostic factors. METHODS/UNASSIGNED:We conducted a retrospective national cohort study including all adults (≥18 years) diagnosed with asbestosis between 2014-2024 according to Dutch Health Council criteria used for compensation. Diagnoses were established by consensus of three independent pulmonologists based on radiological evidence of diffuse pulmonary fibrosis, ≥5 fibre-years of exposure, and lung function impairment according to American Medical Association (AMA) criteria. Demographic data, lung function, work history and overall survival were collected. Incidence per 100 000 persons per year was calculated. RESULTS/UNASSIGNED:Of 1004 applicants, 476 (47.4%) met criteria for asbestosis. Median age at diagnosis was 77 years, and 98.9% were male. Annual incidence ranged from 0.115 to 0.347 per 100 000, with no significant temporal trend (Spearman rho 0.41; p=0.214). AMA class 4 was most common (44.5%) and strongly associated with mortality (hazard ratio 2.52, 95% CI 1.81-3.49). Older age also predicted poorer survival. Median survival ranged from 25.5 months (AMA 4) to 83.4 months (AMA 0-2). Time-dependent modelling showed increasing hazard over time for AMA class 4. CONCLUSIONS/UNASSIGNED:More than two decades after the asbestos ban, asbestosis incidence remains stable. AMA class and age are key predictors of survival.

BACKGROUND:Post-transplant cyclophosphamide (PTCy) for graft-versus-host disease (GVHD) prophylaxis after allogeneic hematopoietic cell transplantation has been associated with clinically significant graft and organ toxicity at the standard dose (50 mg/kg/day on days +3, +4). We conducted a two-center retrospective cohort analysis to assess outcomes after a uniform dose reduction to 40 mg/kg/day on days +3, +4 (PTCy 40-40). OBJECTIVES/OBJECTIVE:The primary objectives were to evaluate cumulative incidence of acute (aGVHD) and chronic GVHD (cGVHD) and relapse. Secondary objectives included assessment of organ toxicity, engraftment, non-relapse mortality (NRM), progression-free survival (PFS), and overall survival (OS). STUDY DESIGN/METHODS:Patients receiving PTCy 40-40 from 11/2020 to 3/2025 at two academic centers were included. Exclusion criteria were history of aplasia after chimeric antigen receptor T-cell therapy as indication for HCT or history of prior HCT complicated by GF. Only the initial HCT was included for patients who had > 1 allogeneic HCT with PTCy. Patients received cyclophosphamide at a dose of 40 mg/kg/day on days +3, +4 after peripheral blood allogeneic HCT. RESULTS:115 patients received PTCy 40-40. Most patients received reduced-intensity conditioning (80%) from matched unrelated donors (63%). Median follow-up was 9.0 months (range, 4.9-28.8). Median time to neutrophil and platelet engraftment was 14 (range, 11-27) and 19 days (range, 15-55), respectively, with one case of primary graft failure and few cardiac, renal, or hepatic events of interest. Cumulative incidence of grades 2-4 aGVHD by day +180 was 13% (95% CI 8-20), with only one grade 3-4 case. Cumulative incidence of moderate-severe cGVHD by 12 months was 13% (95% CI 7-22). At 12 months, relapse was 18% (95% CI 10-27), NRM 5% (95% CI 2-10), PFS 77% (95% CI 66-85), and OS 84% (95% CI 74-91). CONCLUSION/CONCLUSIONS:PTCy 40-40 resulted in low rates of GVHD, toxicity events of interest, and NRM, with excellent 12-month PFS and OS. Our findings from this two-center retrospective cohort analysis suggest that PTCy 40-40 is safe and effective for GVHD prophylaxis after MAC or RIC HCT from any donor type.

We have identified glomerulotubular neck stenoses as a novel feature of kidney histopathology that is associated with chronic kidney disease, independently of interstitial fibrosis and tubular atrophy. Herein we review the occurrence, morphology, and consequences of stenotic glomerulotubular necks, and propose future investigations.

PURPOSE/OBJECTIVE:To assess the prevalence of pancreatic cysts on abdominal MRI and identify factors at the examination, patient, and cyst levels associated with prospective reporting. METHODS:In this retrospective single-center study, high-risk individuals (HRIs, per NCCN criteria) and matched average-risk individuals (ARIs) who underwent abdominal MRI from 2018 to 2023 were identified. Pancreatic cysts prospectively documented on original radiology reports were extracted using a validated large language model. MRI examinations without prospectively reported cysts underwent manual image review by three radiology residents to identify additional visible cysts. A composite reference standard combining prospectively reported and retrospectively identified cysts was used to assess overall cyst prevalence. Patient-, cyst-, and examination-level factors associated with prospective reporting were evaluated using univariable and multivariable logistic regression. RESULTS:The final cohort included 942 patients (314 HRIs, 579 female, mean age 61 ± 10.4 years). Using the composite reference standard, cyst prevalence was 47.9% (451/942), compared with 32.4% (305/942) based on original radiology reports alone. Among the cyst-positive patients identified by the composite reference standard, nearly one-third (32.3%, 146/451) had cysts that were not prospectively reported. Cyst reporting was associated with older age, pancreas-related indication, and larger cyst size: 44.3% of cysts < 5 mm, 77.8% of cysts 5-10 mm, and 95.5% of cysts ≥ 10 mm were reported. HRI status was associated with higher prevalence on unadjusted analysis (OR 1.57 [1.20-2.07], p = 0.001) but not after adjustment for diagnostic-quality MRCP availability (aOR 1.10 [0.82-1.49], p = 0.515). CONCLUSION/CONCLUSIONS:Pancreatic cysts are common but frequently unreported, particularly when < 5 mm. Reporting is associated with indication, cyst size, and age.

INTRODUCTION/BACKGROUND:Down syndrome (DS) is caused by a complete or partial trisomy of chromosome 21, resulting in variable intellectual disabilities and a high risk for early-onset Alzheimer's disease (DS-AD). Dysregulation of the mammalian target of rapamycin (mTOR) and insulin (INS) signaling pathways has been reported in DS. We hypothesized that upstream alterations in these two pathways contribute to hippocampal dysfunction in DS-AD. METHODS:We used spatial transcriptomics and localized proteomic techniques to examine mTOR/INS signaling pathways in subregions of the hippocampus in post mortem tissue from individuals with DS-AD and age-matched neurotypical controls. RESULTS:mTOR pathways were significantly altered in specific hippocampal subfields in DS-AD, and INS pathways were significantly altered in dentate granule neurons. DISCUSSION/CONCLUSIONS:These preliminary spatial transcriptomics and localized proteomics findings demonstrate an interplay between select hippocampal mTOR/INS pathways and cellular populations, suggesting potential novel drug targets and early biomarkers for DS.

INTRODUCTION/BACKGROUND:Adolescents and young adults living with HIV (AYLHIV) experience poor outcomes across the care continuum, and most reside in sub-Saharan Africa. The African Cohort Study (AFRICOS) provides an opportunity to examine HIV outcomes in this population across Kenya, Nigeria, Tanzania, and Uganda. METHODS:We conducted a cross-sectional analysis of AYLHIV aged 15-29 years, enrolled in AFRICOS 2013-2023, and on antiretroviral therapy (ART) ≥ six months. Primary outcomes were HIV viremia and 30-day ART non-adherence. Factors included HIV acquisition route, ART duration, ART class, and site. We used multivariate robust Poisson regression to estimate relative risks (RRs) and 95% confidence intervals (CIs). Site directors were surveyed to assess youth-friendly services. RESULTS:Among 656 participants, the median age was 20.0 years (IQR 17.5-23.3); 41.6% were male, 61.6% had perinatally-acquired HIV, and median duration since HIV diagnosis was nine years. At enrollment, 83.8% had viral suppression (<200 copies/mL) and 80.2% were ART adherent. ART regimen and clinic site were associated with viral suppression: youth on integrase vs. protease inhibitor-based regimens (adjusted relative risk (aRR) 0.38, CI 0.23-0.63, p<0.001), and in Uganda (aRR 0.42, CI 0.20-0.90, p=0.026) or Kisumu, Kenya (aRR 0.40, CI 0.22-0.76, p=0.005) had lower likelihood of non-suppression. Compared to Nigeria, participants from other sites were less likely to report non-adherence (unadjusted RR 0.31-0.44). Youth-friendly service provision varied. CONCLUSIONS:Viral suppression and ART adherence were high among AYLHIV in AFRICOS. Clinic site and ART regimen were associated with outcomes, highlighting the importance of health system factors.

OBJECTIVE:Epidemiologic estimates for age of systemic lupus erythematosus (SLE) diagnosis are limited, particularly for men and racial and ethnic subpopulations in the United States. Leveraging the Centers for Disease Control and Prevention (CDC) National Lupus Registry network of population-based SLE registries, meta-analyses were performed estimating age-specific incidence of SLE by sex, race, and ethnicity. METHODS:The CDC network of SLE registries includes five state-based registries, plus a sixth Indian Health Service registry. Incidence periods spanned calendar years 2002-2018. Registries provided age-specific incidence of SLE, fulfilling the American College of Rheumatology (ACR) SLE classification criteria, per 100,000 person-years, stratified by sex, race, and ethnicity for the meta-analyses. RESULTS:Incidence rates among women were highest for those aged 30-39 (12.7, 95%CI: 9.5-16.8), while rates among men were highest for those aged 60-69 (2.1, 95%CI: 1.3-3.4). Black women aged 20-39 had the highest SLE incidence rates (23.6, 95%CI: 20.7-26.8). Among women diagnosed with SLE before age 20, incidence was highest among Asian (6.5, 95%CI: 2.8-15.2) individuals. Among women diagnosed with SLE after age 60, incidence was highest among American Indian/Alaska Native (9.4, 95%CI: 3.4-15.4) individuals. Weighted percentages show 10.0% of those with SLE were diagnosed before age 20, while 15.1% were diagnosed after age 60. The largest proportion of individuals with SLE, 22.1%, were diagnosed between 30-39 years. CONCLUSIONS:This study provides comprehensive sex- and race-specific estimates of age at SLE diagnosis. The substantial later in life SLE incidence among men and disease burden in pediatric and older populations should raise awareness in considering SLE in the differential diagnosis in previously underrecognized groups.