FOXP3 is the master transcription factor in both murine and human FOXP3⁺regulatory T cells (Tregs), a T-cell subset with a central role in controlling immune responses. Loss of the functional Foxp3 protein inscurfymice leads to acute early-onset lethal lymphoproliferation. Similarly, pathogenic FOXP3 mutations in humans lead to immunodysregulation, polyendocrinopathy, enteropathy, and X-linked (IPEX) syndrome, which are characterized by systemic autoimmunity that typically begins in the first year of life. However, although pathogenicFOXP3mutations lead to overlapping phenotypic consequences in both systems, FOXP3 in human Tregs, but not mouse, is expressed as two predominant isoforms, the full length (FOXP3FL) and the alternatively spliced isoform, delta 2 (FOXP3Δ2). Here, using CRISPR/Cas9 to generate FOXP3 knockout CD4⁺T cells (FOXP3KO^GFPCD4+ T cells), we restore the expression of each isoform by lentiviral gene transfer to delineate their functional roles in human Tregs. When compared to FOXP3FL or FOXP3Δ2 alone, or double transduction of the same isoform, co-expression of FOXP3FL and FOXP3Δ2 induced the highest overall FOXP3 protein expression in FOXP3KO^GFPCD4+ T cells. This condition, in turn, led to optimal acquisition of Treg-like cell phenotypes including downregulation of cytokines, such as IL-17, and increased suppressive function. Our data confirm that co-expression of FOXP3FL and FOXP3Δ2 leads to optimal Treg-like cell function and supports the need to maintain the expression of both when engineering therapeutics designed to restore FOXP3 function in otherwise deficient cells.

Objectives: With the increasing popularity of electronic cigarettes and legalization of recreational marijuana, messaging from websites and social media is shaping product perceptions and use. Quantitative research on the aesthetic appeal of these advertisements from the adolescent and young adult perspective is lacking. We evaluated (1) how adolescents and young adults perceived tobacco and marijuana messaging online and through social media platforms and (2) interactive behaviors related to these messages. Methods: We interviewed 24 participants from the Tobacco Perceptions Study, a longitudinal study of adolescents’ and young adults’ (aged 17-21) tobacco-related perceptions and tobacco use. We collected qualitative data from October 2017 through February 2018, through individual semi-structured interviews, on participants’ experiences and interactions with online tobacco and marijuana advertisements and the advertisements’ appeal. Two analysts recorded, transcribed, and coded interviews. Results: Themes that emerged from the interviews focused on the direct appeal of online messaging to adolescents and young adults; the value of trusting the source; the role of general attitudes and personal decision-making related to using tobacco and/or marijuana; the appeal of messaging that includes colors, interesting packaging, and appealing flavors; and the preference of messages communicated by young people and influencers rather than by industry. Conclusion: These findings suggest the need for increased regulation of social media messaging and marketing of tobacco and marijuana, with a particular focus on regulating social media, paid influencers, and marketing that appeals to adolescents and young adults. The findings also suggest the importance of prevention programs addressing the role of social media in influencing the use of tobacco and marijuana.

This study sought to examine reasons for youth e-cigarette use in association with vaping patterns and cessation behaviors. A national representative sample of current (past 30-day) e-cigarette users in grades 6–12 was analyzed using the National Youth Tobacco Survey (NYTS), conducted from January to March 2020. An exploratory oblique factor analysis using a rotated pattern matrix to select salient variable-factor relationships yielded four subscales related to reasons for youth e-cigarette use. Multivariate logistic regressions were performed to assess the associations of each subscale with vaping patterns (frequent e-cigarette use, dual use of e-cigarettes and other tobacco products) and vaping cessation behaviors (intention to quit vaping and past-year quit attempts). The 2020 NYTS sampled 180 schools with 1769 current e-cigarette users. Four main reasons for vaping were identified through factor analysis, including (1) replacing cigarettes, (2) product characteristics [eg, flavors, concealability, and vape tricks], (3) family/friend use, and (4) curiosity. Curiosity was associated with lower odds of frequent e-cigarette use (adjusted odds ratio [AOR] = 0.5, p < .0001) and dual use of e-cigarettes and other tobacco products (AOR = 0.6, p = .01) but higher odds of intention to quit (AOR = 1.2, p = .26) and past year quit attempts (AOR =1.5, p = .01). Vaping due to product characteristics was associated with higher odds of frequent e-cigarette use (AOR = 1.7, p < .0001) and lower odds of intention to quit (AOR = 0.3, p < .0001) and past year quit attempts (AOR = 0.9, p = .01). Adolescents vape for various reasons that follow distinct patterns and user characteristics. Overall, interventions tailored to address heterogeneous reasons for vaping may help optimize the reduction in youth e-cigarette use. E-cigarettes have surpassed cigarettes and become the most commonly used tobacco product by US youths. Adolescents choose to vape for different reasons. This study examined reasons for youth e-cigarette use and their associations with vaping patterns and cessation behaviors. The product characteristics factor (eg, flavors, concealability, and vape tricks) was associated with more frequent e-cigarette use and lower odds of cessation behaviors, suggesting a need for flavor bans and product design regulation.

Purpose Youth electronic cigarette (e-cigarette) use remains high in the USA, and advertising is a contributor. The purpose of this study was to identify themes and characteristics of popular e-cigarette companies’ advertising after e-cigarette companies became more highly scrutinised in 2018. Methods Using a systematic, quantitative content analysis, three trained coders coded e-cigarette advertisements from JUUL, Puff Bar, Vuse and Blu from 2019 and 2020. Based on previous work, they coded for: type of advertisement, flavours, promotions, product cues, descriptors, claims, imagery, youth-oriented themes and sensational appeals. Results Of the 401 e-cigarette advertisements, the majority were emails (38.2%) and Instagram posts (30.9%). Over half (53.6%) showed flavours other than tobacco, with Puff Bar leading the brands (70.2%; p<0.001). The most frequently used product cues were showing the product (51.4%) or packaging (42.4%). The most common claim was being an alternative to smoking (14.2%). The most frequently used imagery was fruit (14.0%), employed most by Puff Bar (p<0.001). The only youth-oriented theme present was humour (4.2%). Positive sensations (eg, good taste, good smell or satisfying; 17.1%) was the most common form of appeal, with Puff Bar using it at the highest frequency (p<0.001). Conclusion Even with heightened scrutiny of e-cigarette brands, advertisements still included youth-appealing content such as flavours, fruit imagery and positive sensations. Puff Bar led in all these categories, and it rapidly gained market share after market leader JUUL limited the sales of its flavoured products. Research should continue to monitor the characteristics of e-cigarette advertisements and consider their impact on youth.