Optimization of mRNA extraction from human nasal mucosa biopsies for gene expression profile analysis by qRT-PCR.

Quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) is the gold-standard method for analyzing modifications in gene expression in cells and tissues. However, large quantities of high-quality RNA samples are needed for analyzing the expression of multiple genes from one human tissue sample. Here, we provide an optimized protocol for extracting large amounts of RNA from human nasal mucosal biopsies. The quality and quantity of samples were sufficient for qRT-PCR analyses of the expressions of various genes, in duplicate. In contrast to other protocols, we optimized RNA isolation to increase the amount from nasal biopsy samples for analyses of multiple genes. In most previous publications, expressions of only one or a few genes, including housekeeping genes, were analyzed because the amount of biological material was small. We were able to improve our protocol with respect to the yield and quality of RNA. This is likely to produce better results from molecular analyses of very small biopsy samples of human nasal mucosa.

Real-world-effectiveness of biological treatment for severe chronic rhinosinusitis with nasal polyps.

BACKGROUND: During the last two years, three different monoclonal antibodies have been approved in many countries for the treatment of patients suffering from severe chronic rhinosinusitis with nasal polyps (CRSwNP). Their efficacy has been demonstrated through large double-blind placebo-controlled clinical studies. Until now, only very limited reports on real-world data regarding this therapy have been published. METHODS: This per protocol analysis included patients with an indication for biological treatment because of uncontrolled CRSwNP, despite long-term nasal steroid treatment, systemic steroid use and/ or endonasal sinus surgery. Baseline data on demographics, medical history and comorbidities, polyp score, quality of life and sense of smell (using Sniffin' Sticks) were assessed and a treatment with either dupilumab or omalizumab was started. The patients were followed up after three and six months. The changes in polyp score, quality-of-life measures and olfaction were noted. RESULTS: 70 consecutive patients were evaluated during the study. Of the patients, 49 were treated with dupilumab and 21 with omalizumab. The polyp score decreased significantly after three and six months, and the quality-of-life parameters and olfaction increased. More than 90% of patients showed a moderate to excellent response to the therapy and there was no difference in the overall response between the two treatments. Olfaction improved in two thirds of the patients, but one third was still anosmic after six months treatment. CONCLUSIONS: This real-world study shows the effectiveness of the monoclonal antibodies dupilumab and omalizumab in the treatment of severe CRSwNP. Nasal polyp scores and quality-of-life parameters as well as measured olfactory function were improved after just three months. The response after guideline-based criteria was insufficient only in 5 patients of this cohort.