Anti-C4B monoclonal antibody, clone FQS22314-38

The microglial triggering receptor expressed on myeloid cells 2 (TREM2) signals via the activatory membrane adaptor molecule TYROBP. Genetic variants or mutations of TREM2 or TYROBP have been linked to inflammatory neurodegenerative diseases associated with aging. The typical aging process goes along with microglial changes and mild neuronal loss, but the exact contribution of TREM2 is still unclear. Aged TREM2 knock-out mice showed decreased age-related neuronal loss in the substantia nigra and the hippocampus. Transcriptomic analysis of the brains of 24 months old TREM2 knock-out mice revealed 211 differentially expressed genes mostly downregulated and associated with complement activation and oxidative stress response pathways. Consistently, 24 months old TREM2 knock-out mice showed lower transcription of microglial (Aif1 and Tmem119), oxidative stress markers (Inos, Cyba, and Cybb) and complement components (C1qa, C1qb, C1qc, C3, C4b, Itgam, and Itgb2), decreased microglial numbers and expression of the microglial activation marker Cd68, as well as accumulation of oxidized lipids. Cultured microglia of TREM2 knock-out mice showed reduced phagocytosis and oxidative burst. Thus, microglial TREM2 contributes to age-related microglial changes, phagocytic oxidative burst, and loss of neurons with possible detrimental effects during physiological aging.

Objective: The proprietary cyanoacrylate closure (CAC) system vs radiofrequency ablation (RFA) trial (VenaSeal Sapheon Closure System Pivotal Study [VeClose]) showed that CAC, a nontumescent. nonthermal. nonsclerosant ablation technique, was effective and noninferior to RFA in vein closure with good 36-month outcomes. Conducted under a separate protocol. the aim of this extended follow-up was to assess the long-term safety and effectiveness of CAC and RFA for the treatment of incompetent great saphenous veins (GSV) at 5 years (60 months) of follow-up. Methods: This 60-month extension study was conducted for all patients who completed the randomized VeClose study and who were willing to participate. The pivotal VeClose study included patients with symptomatic moderate to severe varicosities (Clinical, Etiology, Anatomy, and Pathophysiology [CEAP] class C2-C4b) and symptomatic GSV incompetence who were randomly assigned (1:1) to either CAC or RFA. The primary outcome measure of this 60-month extension study was complete closure of the target vein, with planned exploratory analysis of noninferiority. Secondary outcomes included CEAP class; completion of the Venous Clinical Severity Score, EuroQol-Five Dimension survey, and Aberdeen Varicose Vein Questionnaire; patient satisfaction with treatment; adverse events (AEs) related to target GSV; and details of adjunctive procedures. Results: A total of 89 patients completed the 60-month visit, which included 47 from the CAC group, 33 from the RFA group, and 9 CAC roll-in patients. No new recanalization events have been observed in the groups between 36 and 60 months of follow-up. At 60 months, Kaplan-Meier estimates for freedom from recanalization in the randomized CAC and RFA groups were 91.4% and 85.2%, respectively, demonstrating noninferiority of CAC compared with RFA. Both groups demonstrated sustained improvements in EuroQol-Five Dimension and quality of life measures through 60 months. Whereas patients assigned to C0 or C1 clinical class were excluded from the original study, more than half of all returning patients (64% [57/89]) were now assigned to C0 or C1, suggesting an improved clinical class from baseline. Furthermore, 41.1% of returning CAC patients and 39.4% of returning RFA patients are presently at least two CEAP clinical classes lower than at baseline. No longterm device- or procedure-related serious AEs occurred in either group between 36- and 60-month follow-up. Conclusions: CAC and RFA were effective in achieving complete target vein closure of the GSV at long-term follow-up, with CAC demonstrating continued noninferiority to RFA. CAC was also associated with sustained improvements in symptoms and quality of life, lower CEAP class, and high level of patient satisfaction without serious AEs between 36 and 60 months.