Protocol for genomic editing in human resting primary NK cells and NK-92 cells via CRISPR-Cas9 ribonucleoproteins.

Here, we present a protocol to perform CRISPR-Cas9 genome editing in human resting primary natural killer (NK) and NK-92 cells. We describe steps for guide RNA selection, ribonucleoprotein (RNP) complex formation, delivery via Nucleofection, and analysis of CRISPR edits to assess editing efficiencies. This protocol offers a tool for functional studies in NK cells, paving the way for potential applications in immunotherapy and beyond. We also discuss limitations such as off-target effects and cell-type-specific considerations.

Managing Pediatric Asthma Exacerbations: The Role of Timely Systemic Corticosteroid Administration in Emergency Care Settings-A Multicentric Retrospective Study.

BACKGROUND: Asthma is the most prevalent chronic respiratory condition in children. An asthma exacerbation (AE) is a frequent reason for emergency department (ED) visits. An important step in the management of a moderate to severe AE is the administration of systemic corticosteroids (SCS) within 1 h after ED presentation. This study aimed to determine the timing of SCS administration and correlate this with the length of stay and oxygen therapy duration and to explore factors predicting timely administration. METHODS: This study used a retrospective multicenter observational design based on electronic medical records review. Children aged < 18 years, presenting to the ED with a moderate to severe AE were included. RESULTS: 205 patients were included. Only 28 patients received SCS within 60 min after ED arrival. The median time to SCS administration was 169 min (Q1 92-Q3 380). A correlation was found between timing and oxygen treatment duration (r = 0.363, p < 0.001) and length of stay (r = 0.368, p < 0.001). No patient characteristics predicted timely SCS administration. CONCLUSIONS: Three in four children who presented with a moderate to severe AE at the ED did not receive SCS within the first hour. A prolonged timing of SCS administration correlated with a prolonged length of stay and extended need for oxygen support.

Correction: Krayem et al. The Benefit of Reactivating p53 under MAPK Inhibition on the Efficacy of Radiotherapy in Melanoma. Cancers 2019, 11, 1093.

In the original article [...].

Establishment of head and neck squamous cell carcinoma mouse models for cetuximab resistance and sensitivity.

Aim: Acquired resistance to the targeted agent cetuximab poses a significant challenge in finding effective anti-cancer treatments for head and neck squamous cell carcinoma (HNSCC). To accurately study novel combination treatments, suitable preclinical mouse models for cetuximab resistance are key yet currently limited. This study aimed to optimize an acquired cetuximab-resistant mouse model, with preservation of the innate immunity, ensuring intact antibody-dependent cellular cytotoxicity (ADCC) functionality. Methods: Cetuximab-sensitive and acquired-resistant HNSCC cell lines, generated in vitro, were subcutaneously engrafted in Rag2 knock-out (KO), BALB/c Nude and CB17 Scid mice with/without Matrigel or Geltrex. Once tumor growth was established, mice were intraperitoneally injected twice a week with cetuximab for a maximum of 3 weeks. In addition, immunohistochemistry was used to evaluate the tumor and its microenvironment. Results: Despite several adjustments in cell number, cell lines and the addition of Matrigel, Rag2 KO and BALB/C Nude mice proved to be unsuitable for xenografting our HNSCC cell lines. Durable tumor growth of resistant SC263-R cells could be induced in CB17 Scid mice. However, these cells had lost their resistance phenotype in vivo. Immunohistochemistry revealed a high infiltration of macrophages in cetuximab-treated SC263-R tumors. FaDu-S and FaDu-R cells successfully engrafted into CB17 Scid mice and maintained their sensitivity/resistance to cetuximab. Conclusion: We have established in vivo HNSCC mouse models with intact ADCC functionality for cetuximab resistance and sensitivity using the FaDu-R and FaDu-S cell lines, respectively. These models serve as valuable tools for investigating cetuximab resistance mechanisms and exploring novel drug combination strategies.