背景:囊性纤维化跨膜传导调节因子(CFTR)基因中的许多致病变体仍未表征和未处理。恢复受损的CFTR蛋白的功能是个性化医疗的目标,特别是携带罕见CFTR变异的患者。在这项研究中,用CFTR调节剂或罗氟司特治疗后评估与罕见R334W变体相关的功能缺陷,磷酸二酯酶-4抑制剂(PDE4i)。
方法:来自R334W/2184insA和R334W/2183AA>G基因型受试者的直肠类器官用于进行Forskolin诱导的肿胀(FIS)测定。类器官未治疗或用调节剂VX-770(I)治疗,VX-445(E),和VX-661(T)混合,和他们的组合(ETI)。罗氟司特(R)单独使用或作为I+R的组合使用。
结果:我们的数据显示,单独使用I治疗后,FIS发生率显着增加。调制器的组合使用,例如ETI,没有比我更多的肿胀,也不在蛋白质成熟。用R处理显示与I相似的FIS反应增加,和组合R+I显著增加CFTR活性的拯救。
结论:两种基因型均观察到等效I和ETI治疗功效。此外,使用I+R组合观察到显著的类器官肿胀,这支持最近发表的数据,描述了只有I在携带变体R334W的患者中的增强作用,同时,证实了包括PDE4抑制剂的策略的作用,以进一步增强I对该变体的作用。
BACKGROUND: Many disease-causing variants in the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene remain uncharacterized and untreated. Restoring the function of the impaired CFTR protein is the goal of personalized medicine, particularly in patients carrying rare CFTR variants. In this study, functional defects related to the rare R334W variant were evaluated after treatment with CFTR modulators or Roflumilast, a phosphodiesterase-4 inhibitor (PDE4i).
METHODS: Rectal organoids from subjects with R334W/2184insA and R334W/2183AA > G genotypes were used to perform the Forskolin-induced swelling (FIS) assay. Organoids were left drug-untreated or treated with modulators VX-770 (I), VX-445 (E), and VX-661 (T) mixed, and their combination (ETI). Roflumilast (R) was used alone or as a combination of I + R.
RESULTS: Our data show a significant increase in FIS rate following treatment with I alone. The combined use of modulators, such as ETI, did not increase further swelling than I alone, nor in protein maturation. Treatment with R shows an increase in FIS response similar to those of I, and the combination R + I significantly increases the rescue of CFTR activity.
CONCLUSIONS: Equivalent I and ETI treatment efficacy was observed for both genotypes. Furthermore, significant organoid swelling was observed with combined I + R used that supports the recently published data describing a potentiating effect of only I in patients carrying the variant R334W and, at the same time, corroborating the role of strategies that include PDE4 inhibitors further to potentiate the effect of I for this variant.