CRISPR-Cas9‒Based Genomic Engineering in Keratinocytes: From Technology to Application

CRISPR-Cas9 is the most straightforward genome-editing tool to date. However, its implementation across disciplines is hampered by variable genome-editing efficiencies, reduced cell viability, and low success rates in obtaining clonal cell lines. This review aims to recognize all CRISPR-Cas9‒related work within the experimental dermatology field to identify key factors for successful strategies in the different keratinocyte (KC) cell sources available. On the basis of these findings, we conclude that most groups use immortalized KCs for generating knockout KCs. Our critical considerations for future studies using CRISPR-Cas9, both for fundamental and clinical applications, may guide implementation strategies of CRISPR-Cas9 technologies in the (experimental) dermatology field

Knee osteoarthritis and comorbidity: a feasibility study on an interactive exercise therapy course for physiotherapists

Purpose : A structured, tailored exercise therapy strategy was found to significantly improve physical functioning, reduce pain and was safe for patients with knee osteoarthritis (OA) and severe comorbidity. The intervention was performed in a specialized, secondary care center. Before the intervention can be implemented in primary care, appropriate education as well as insight into barriers and facilitators is needed. This study aimed to 1) evaluate the feasibility and effect of an interactive course on the exercise therapy strategy for patients with OA and comorbidity for physiotherapists (PTs) working in primary care; and 2) map barriers for a larger scale implementation of the protocol in primary care. Methods : A pre-posttest study was performed among PTs who were member of a network for rheumatic diseases and PTs from regional subdivisions of the Royal Dutch Society for Physical Therapy (KNGF) in the Netherlands (North-Holland and Mid-Holland) all working in primary care. PTs were offered a postgraduate blended educational course consisting of an e-learning lecture (7 hours study load) and two interactive workshops (each 3 hours study load). Measures of its feasibility and effectiveness included a questionnaire on knowledge (50 multiple choice questions, score ranging from 1 to 50) before (T0) and two weeks after the course (T1)) and a patient vignette to measure clinical reasoning (nine open questions, score ranging from 0 to 5) before the course (T0) and six months after the course (T2). Course satisfaction was administered on a 0-10 point scale (higher score means more satisfaction), directly after the course. Barriers for using the protocol were measured at T2 by means of a 27 item questionnaire, comprising five different dimensions: (i) Design, Content and Feasibility; (ii) Change in working method; (iii) Knowledge and Skills; (iv) Applicability; and (v) Social environment (each item was scored on a 5-point Likert scale, ranging from 0 totally agree to 4 totally disagree). Results : In total, 34 physiotherapists were included. Statistically significant (P < 0.05) improvement was found in knowledge about knee OA and comorbidity between baseline and two- weeks post education, with an average increase of 4.4 points above the baseline score. Also, a statistically significant improvement (P < 0.05) was found for clinical reasoning on adapting knee OA exercise therapy to the comorbid disease between baseline and six- months post education. Overall, the PTs were satisfied with the educational course (7.9 points (SD 0.9) (n ¼ 33)). The majority of PTs found the protocol to be supportive regarding clinical reasoning and clinical decision making. In a period of six months, 15 out of 34 PTs had treated at least one patient with knee OA and comorbidity according to the protocol. Perceived barriers for implementation included the small number of patients with OA and severe comorbidity being referred or referring themselves, treatment time needed to provide care according the protocol, and the limited number of treatments reimbursement by the insurance companies. Conclusions : An interactive educational course on exercise therapy for knee OA patients with comorbidity proved to be effective in improving knowledge and clinical reasoning skills of primary care PTs. Main barriers for larger scale implementation include limited referrals of patients with knee OA and severe comorbidity to PTs and limited number of treatments reimbursement by the insurance companies. Specialists and patients should be encouraged to consider exercise therapy as a treatment option for patients with knee OA and comorbidity

Gram-positive anaerobic cocci guard skin homeostasis by regulating host-defense mechanisms.

In atopic dermatitis (AD), chronic skin inflammation is associated with skin barrier defects and skin microbiome dysbiosis including a lower abundance of Gram-positive anaerobic cocci (GPACs). We here report that, through secreted soluble factors, GPAC rapidly and directly induced epidermal host-defense molecules in cultured human keratinocytes and indirectly via immune-cell activation and cytokines derived thereof. Host-derived antimicrobial peptides known to limit the growth of Staphylococcus aureus-a skin pathogen involved in AD pathology-were strongly upregulated by GPAC-induced signaling through aryl hydrocarbon receptor (AHR)-independent mechanisms, with a concomitant AHR-dependent induction of epidermal differentiation genes and control of pro-inflammatory gene expression in organotypic human epidermis. By these modes of operandi, GPAC may act as an "alarm signal" and protect the skin from pathogenic colonization and infection in the event of skin barrier disruption. Fostering growth or survival of GPAC may be starting point for microbiome-targeted therapeutics in AD