A versatile transposon-based technology to generate loss- and gain-of-function phenotypes in the mouse liver

Background Understanding the contribution of gene function in distinct organ systems to the pathogenesis of human diseases in biomedical research requires modifying gene expression through the generation of gain- and loss-of-function phenotypes in model organisms, for instance, the mouse. However, methods to modify both germline and somatic genomes have important limitations that prevent easy, strong, and stable expression of transgenes. For instance, while the liver is remarkably easy to target, nucleic acids introduced to modify the genome of hepatocytes are rapidly lost, or the transgene expression they mediate becomes inhibited due to the action of effector pathways for the elimination of exogenous DNA. Novel methods are required to overcome these challenges, and here we develop a somatic gene delivery technology enabling long-lasting high-level transgene expression in the entire hepatocyte population of mice. Results We exploit the fumarylacetoacetate hydrolase (Fah) gene correction-induced regeneration in Fah-deficient livers, to demonstrate that such approach stabilizes luciferase expression more than 5000-fold above the level detected in WT animals, following plasmid DNA introduction complemented by transposon-mediated chromosomal gene transfer. Building on this advancement, we created a versatile technology platform for performing gene function analysis in vivo in the mouse liver. Our technology allows the tag-free expression of proteins of interest and silencing of any arbitrary gene in the mouse genome. This was achieved by applying the HADHA/B endogenous bidirectional promoter capable of driving well-balanced bidirectional expression and by optimizing in vivo intronic artificial microRNA-based gene silencing. We demonstrated the particular usefulness of the technology in cancer research by creating a p53-silenced and hRas G12V-overexpressing tumor model. Conclusions We developed a versatile technology platform for in vivo somatic genome editing in the mouse liver, which meets multiple requirements for long-lasting high-level transgene expression. We believe that this technology will contribute to the development of a more accurate new generation of tools for gene function analysis in mice.Peer reviewe

An empirical assessment of the factors infuencing acceptance of COVID‑19 vaccine uptake between Kenyan and Hungarian residing populations: A cross‑sectional study

The development of efective, safe, and acceptable vaccines is a long process. COVID-19 vaccine hesitancy continues to elicit mixed reactions among diferent quarters despite numerous evidence of their efectiveness. This study aimed to determine the availability and acceptance rates of SARS-CoV-2 vaccines, among Kenyan and Hungarian residing populations and the underlying reasons contributing to the hesitancy of uptake. A non-probability, snowball sampling design was employed, and a survey questionnaire tool link was expeditiously disseminated. Data were carefully analyzed descriptively. Demographic variables, COVID-19 awareness, possible exposure, reasons associated with hesitancy in taking up a vaccine, choice of a vaccine, and availability of vaccines among other important variables were tested to explore their associations with vaccine acceptance rates between the two distinct countries. A total of 1960 participants were successfully enrolled in the research study, while 67 participants were excluded based on the inclusion criterion set. There was, however, no signifcant diference in COVID-19 public awareness between the Kenyan and Hungarian-residing participants, p = 0.300. Of the respondents, 62.4% were willing and ready to receive vaccines against COVID-19 disease. There was a signifcant diference (p= 0.014) between the Kenyan and Hungarian-residing respondents concerning vaccine uptake and acceptance rates. The vaccine acceptance rates in Hungary were higher than in Kenya, with mean= 0.27, SD= 0.446, S. E= 0.045 for the Hungarian population sample and mean= 0.40, SD= 0.492, S. E= 0.026, for the Kenyan sample respectively. Concerning gender and vaccine acceptance, there was a notable signifcant diference between males and females, p = 0.001, where the mean for males and females were 0.29 and 0.46 respectively. Acceptance rates among males were higher than among females. The functions of One-Way ANOVA and Chi-square were used to establish any signifcant diferences and associations between means and variables respectively. Concerns regarding the safety, efcacy, and accuracy of information about the developed vaccines are signifcant factors that must be promptly addressed, to arrest crises revolving around COVID-19 vaccine hesitancy, especially in Kenya and among females in both populations, where acceptance rates were lower. Expansion of the screening program to incorporate antibody (serology) tests, is also highly recommended in the present circumstance. Equitable distribution of vaccines globally should be encouraged and promoted to adequately cover low- and middle-income countries. To enhance efective combat on vaccination hesitancy and apprehension in diferent countries, mitigation techniques unique to those countries must be adopted.</p