The elimination of amyloid-beta (Aβ) plaques in Alzheimer's disease patients after treatment with anti-Aβ antibodies such as lecanemab and aducanumab is supported by a substantially decreased signal in amyloid positron emission tomography (PET) imaging. However, this decreased PET signal has not been matched by a similar substantial effect on cognitive function. There may be several reasons for this, including short treatment duration and advanced disease stages among the patients. However, one aspect that has not been investigated, and the subject of this study, is whether antibody engagement with amyloid plaques inhibits the binding of amyloid-PET ligands, leading to a false impression of Aβ removal from the brain. In the present study, tg-ArcSwe mice received three injections of RmAb158, the murine version of lecanemab or phosphate-buffered saline (PBS) before the administration of the amyloid-PET radioligand [C]PiB, followed by isolation of brain tissue. Autoradiography showed that RmAb158- and PBS-treated mice displayed similar [C]PiB binding. Moreover, the total Aβ1-40 levels, representing the major Aβ species of plaques in the tg-ArcSwe model, as well as soluble triggering receptor on myeloid cells 2 (sTREM2) levels, were similar in both groups. Interestingly, the concentration of soluble Aβ aggregates was decreased in the RmAb158-treated group, along with a small but significant decrease in the total Aβ1-42 levels. In conclusion, this study indicates that the binding of [C]PiB to Aβ accurately mirrors the load of Aβ plaques in the brain, aligning with how amyloid-PET is interpreted in clinical studies of anti-Aβ antibodies. However, early treatment effects on soluble Aβ aggregates and Aβ1-42 levels were not detected.
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http://dx.doi.org/10.1111/jnc.16127 | DOI Listing |
J Virol
January 2025
Infection Biology Unit, German Primate Centre - Leibniz Institute for Primate Research, Göttingen, Germany.
The naturally occurring mutation E484D in the spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can render viral entry ACE2 independent and imdevimab resistant. Here, we investigated whether the cellular proteins ASGR1, DC-SIGN, and TMEM106B, which interact with the viral S protein, can contribute to these processes. Employing S protein-pseudotyped particles, we found that expression of ASGR1 or DC-SIGN jointly with TMEM106B allowed for robust entry of mutant E484D into otherwise non-susceptible cells, while this effect was not observed upon separate expression of the single proteins and upon infection with SARS-CoV-2 wild type (WT).
View Article and Find Full Text PDFGynecol Oncol
January 2025
Department of Investigational Cancer Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States.
Introduction: Molecular alterations in the PI3K/AKT and Ras/Raf/MEK/ERK pathways are frequently observed in patients with endometrial cancers. However, mTOR inhibitors, such as temsirolimus, have modest clinical benefits. In addition to inducing metabolic changes in cells, metformin activates AMPK, which in turn inhibits the mTOR pathway.
View Article and Find Full Text PDFEndocrinol Diabetes Metab Case Rep
January 2025
Summary: Palmoplantar keratoderma (PPK), characterised by excessive epidermal thickening of the skin on the palms and/or plantar surfaces of the feet, can be hereditary or acquired. Here, we report a case of a 53-year-old woman with a history of sub-optimally controlled diabetes mellitus presenting with fevers and decreased Glasgow Coma Scale (GCS) to a tertiary hospital. She was diagnosed with diabetic ketoacidosis (DKA), with blood glucose at 40 mmol/L and ketones at 7 mmol/L, in the setting of a methicillin-sensitive Staphylococcus aureus necrotising soft tissue back infection.
View Article and Find Full Text PDFBackground: Recent advances in diagnostics have made it possible to identify early signs of the pathophysiological changes underlying Alzheimer's Disease (AD) via blood tests. However, the use of blood-based biomarkers (BBBMs) for the early detection of AD may be limited in primary care settings despite its potential for wide access and early detection of AD (PMID: 37295421) Therefore, there is a need to understand the barriers and facilitators of BBBM testing for AD in primary care.
Method: We employed a combination of qualitative research, advisory board, and quantitative survey to engage with clinical/scientific advisors and community-based physicians in primary care.
Background: Qualitative patient interviews are increasingly conducted alongside clinical trials; interviews administered early in drug development can yield insight into the patient journey. Examination among patient subgroups may identify factors that influence the patient experience, including trial participation. As part of the INTERCEPT-AD phase 1 study evaluating the safety and tolerability of the Aβ oligomer-targeting monoclonal antibody ACU193, we conducted semi-structured qualitative interviews among a subset of participants with mild cognitive impairment (MCI) or mild dementia due to Alzheimer's disease (AD) and their study partners to obtain feedback on their trial experience and the decision-making process preceding trial enrollment; results were compared between study participant genders.
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