👤 Jim E Riviere

A comprehensive understanding of protein corona (PC) composition is critical for engineering nanoparticles (NPs) with optimal safety and therapeutic performance, because the PC governs NP pharmacokinetics, biodistribution, and cellular interactions. Yet systematic analyses are hampered by the absence of standardized, richly annotated data sets. Here, we introduce the Protein Corona Database (PC-DB), which compiles data from 83 studies (2000-2024) and integrates 817 NP formulations with quantitative profiles of 2497 adsorbed proteins. The PC-DB exposes pronounced heterogeneity in NP materials (metal 28.8%, silica 22.8%, lipid-based 14.8%), surface modifications, sizes (1-1400 nm), and ζ-potentials (-70 to +70 mV). Subsequent meta-analysis shows that silica, polystyrene, and lipid-based NPs smaller than 100 nm with moderately negative to neutral ζ-potentials preferentially bind the lipoproteins APOE and APOB-100, which are linked to receptor-mediated uptake and enhanced delivery efficiency. In contrast, metal and metal-oxide NPs carrying highly negative surface charge enrich complement component C3, indicating a greater likelihood of immune recognition and clearance. Interpretable machine learning models (LightGBM and XGBoost; ROC-AUC > 0.85) confirm NP size, ζ-potential, and incubation time as the most influential predictors of protein adsorption. These results delineate how physicochemical parameters dictate PC composition and illustrate the power of predictive modeling to guide rational NP design. Show less

The apolipoprotein E (APOE) gene is the best established genetic risk factor for Alzheimer's disease in later life, with the ε4 allele conferring higher risk. APOE disclosure is becoming increasingly common in the clinical care of people with Alzheimer's disease and in cognitively unimpaired adults. In this study, we aimed to describe changes in measures of genetic disease knowledge and psychiatric symptoms following APOE disclosure to cognitively unimpaired adults. Data were collected as part of the screening phase of the global, multicentre, Alzheimer's Prevention Initiative Generation Study 1 (NCT02565511). Eligible individuals were cognitively unimpaired (Mini-Mental State Exam total score ≥24), aged 60-75 years, and psychologically pre-screened for readiness (by measures of depressive symptoms and anxiety) to receive their APOE genotype from a health-care provider. Participants were assessed before disclosure, and 2-7 days, 6 weeks, 6 months, and 12 months after disclosure. Multivariable linear and ordinal logistic regressions were used to compare changes in genetic disease knowledge, anxiety, depression, and distress by APOE4 genotype status, adjusting for key covariates, with a focus on 2-7 days after disclosure. Multiple imputation by chained equations methods was used to account for missing outcome data. The trial took place between Nov 30, 2015, and Sept 23, 2019. In total, 9496 participants (including 790 APOE4 homozygotes, 4869 heterozygotes, and 3837 non-carriers) learned their APOE genotype from a health-care provider as part of Generation Study 1 screening. 4038 (42·5%) participants were in the 65-69-year age group, 5790 (61·0%) were female, 3706 (39·0%) were male, and 8862 (93·3%) self-identified as White. Increase in genetic disease knowledge 2-7 days after disclosure was greater in APOE4 homozygotes (mean 1·19 [SD 3·95]) than in heterozygotes (0·78 [3·95], p=0·042) and non-carriers (0·29 [3·96], p=0·0002). Disease-specific distress 2-7 days after disclosure increased more in homozygotes (2·25 [6·42]) than in heterozygotes (0·53 [5·08], p<0·0001) and non-carriers (0·79 [4·95], p<0·0001). Levels of anxiety 2-7 days after disclosure increased in homozygotes (0·17 [2·95]) but decreased in heterozygotes (-0·67 [2·68], p<0·0001) and non-carriers (-0·66 [2·67], p<0·0001). There were no significant changes in depressive symptoms following disclosure for any APOE4 group. Notably, for all APOE4 groups, increases in distress and anxiety were small and did not reach predefined levels of clinical concern. In cognitively unimpaired, psychologically pre-screened adults, APOE disclosure by a trained health-care provider was generally safe and well tolerated, consistent with results from previous studies. To our knowledge, this is the largest study experience of APOE disclosure to date, especially for homozygotes, and is notable for the older age of participants compared with previous research. These results are timely and important given anticipated increases in APOE disclosure to guide clinical decision making once an Alzheimer's disease prevention treatment is approved for cognitively unimpaired adults or if patients' family members are interested in genetic testing. Scalable approaches for returning Alzheimer's disease risk information are critical to meeting anticipated demand. Results from this study may be useful to bolster clinical translatability of disclosure programmes. The National Institute on Aging, Alzheimer's Association, Banner Alzheimer's Foundation, GHR Foundation, F-Prime Biomedical Research Initiative (FBRI), and Novartis Pharma. Show less

The Alzheimer's Prevention Initiative (API) Generation Studies evaluated the BACE inhibitor umibecestat for Alzheimer's disease (AD) prevention. The studies were terminated early, and the reversibility of umibecestat's side effects was assessed. Cognitively unimpaired 60- to 75-year-old apolipoprotein E (APOE) ε4 homozygotes and heterozygotes (the latter with elevated brain amyloid deposition) (n = 1556) received umibecestat (50 or 15 mg daily) or placebo for 7 months on average and were followed for a median (interquartile range) of 4 (3 to 6) months after washout. Compared to placebo, umibecestat-treated participants had small, non-progressive, but statistically significant decline in performance on certain cognitive batteries including Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and API Preclinical Composite Cognitive test, but not Clinical Dementia Rating-Sum of Boxes. RBANS differences were no longer significant at the end of follow-up. In people at genetic risk for AD, high-dose beta-site amyloid precursor protein cleaving enzyme (BACE) inhibition was associated with early mild cognitive worsening, which reversed shortly after washout, suggesting a symptomatic side effect not associated with neurodegeneration. Fully anonymized data, images, and samples are available upon request for further research on BACE inhibition. This is the first trial with blinded assessment of reversibility of BACE inhibitor side effects. Umibecestat was tested in cognitively unimpaired persons at genetic risk for AD. Umibecestat led to early mild cognitive decline that reversed shortly after washout. This suggests a potentially manageable effect not associated with neurodegeneration. Further research may determine the future of BACE inhibition in AD prevention. Show less

Alzheimer's Prevention Initiative Generation Study 1 evaluated amyloid beta (Aβ) active immunotherapy (vaccine) CAD106 and BACE-1 inhibitor umibecestat in cognitively unimpaired 60- to 75-year-old participants at genetic risk for Alzheimer's disease (AD). The study was reduced in size and terminated early. Results from the CAD106 cohort are presented. Sixty-five apolipoprotein E ε4 homozygotes with/without amyloid deposition received intramuscular CAD106 450 μg (n = 42) or placebo (n = 23) at baseline; Weeks 1, 7, 13; and quarterly; 51 of them had follow-up Aβ positron emission tomography (PET) scans at 18 to 24 months. CAD106 induced measurable serum Aβ immunoglobulin G titers in 41/42 participants, slower rates of Aβ plaque accumulation (mean [standard deviation] annualized change from baseline in amyloid PET Centiloid: -0.91[5.65] for CAD106 versus 8.36 [6.68] for placebo; P < 0.001), and three amyloid-related imaging abnormality cases (one symptomatic). Despite early termination, these findings support the potential value of conducting larger prevention trials of Aβ active immunotherapies in individuals at risk for AD. This was the first amyloid-lowering prevention trial in persons at genetic risk of late-onset Alzheimer's disease (AD). Active immunotherapy targeting amyloid (CAD106) was tested in this prevention trial. CAD106 significantly slowed down amyloid plaque deposition in apolipoprotein E homozygotes. CAD106 was generally safe and well tolerated, with only three amyloid-related imaging abnormality cases (one symptomatic). Such an approach deserves further evaluation in larger AD prevention trials. Show less