Department of Medicine, Division of General Pathology, University of Verona, Strada Le Grazie 8, 37134 Verona, Italy.
Endoscopic Surgery Unit, Azienda Ospedaliera Universitaria Integrata Verona, 37126 Verona, Italy.
Int J Mol Sci. 2023 Mar 8;24(6):5199. doi: 10.3390/ijms24065199.
An Italian, 46-year-old female patient carrying the complex allele p.[R74W;V201M;D1270N] in trans with CFTR dele22_24 was diagnosed at the Cystic Fibrosis (CF) Center of Verona as being affected by CF-pancreatic sufficient (CF-PS) in 2021. The variant V201M has unknown significance, while both of the other variants of this complex allele have variable clinical consequences, according to the CFTR2 database, with reported clinical benefits for treatment with ivacaftor + tezacaftor and ivacaftor + tezacaftor + elexacaftor in patients carrying the R74W-D1270N complex allele, which are currently approved (in USA, not yet in Italy). She was previously followed up by pneumologists in northern Italy because of frequent bronchitis, hemoptysis, recurrent rhinitis, lung colonization, bronchiectasis/atelectasis, bronchial arterial embolization and moderately compromised lung function (FEV1: 62%). Following a sweat test with borderline results, she was referred to the Verona CF Center where she presented abnormal values in both optical beta-adrenergic sweat tests and intestinal current measurement (ICM). These results were consistent with a diagnosis of CF. CFTR function analyses were also performed in vitro by forskolin-induced swelling (FIS) assay and short-circuit currents (Isc) in the monolayers of the rectal organoids. Both of these assays showed significantly increased CFTR activity following treatment with the CFTR modulators. Western-blot analysis revealed increased fully glycosylated CFTR protein after treatment with correctors, in line with the functional analysis. Interestingly, tezacaftor, together with elexacaftor, rescued the total organoid area under steady-state conditions, even in the absence of the CFTR agonist forskolin. In conclusion, in ex vivo and in vitro assays, we measured a residual function that was significantly enhanced by in vitro incubation with CFTR modulators, especially by ivacaftor + tezacaftor + elexacaftor, suggesting this combination as a potentially optimal treatment for this case.
一位 46 岁的意大利女性患者，携带 CFTR 基因上 trans 位置的复杂杂合突变 p.[R74W;V201M;D1270N]，于 2021 年在维罗纳囊性纤维化（CF）中心被诊断为 CF-胰腺功能充分（CF-PS）。根据 CFTR2 数据库，V201M 突变的意义未知，而该复杂等位基因的其他两个变异均具有可变的临床后果，携带 R74W-D1270N 复合等位基因的患者使用 ivacaftor + tezacaftor 和 ivacaftor + tezacaftor + elexacaftor 治疗具有临床获益，这些药物目前已被批准（在美国，尚未在意大利）。由于经常患支气管炎、咯血、复发性鼻炎、肺部定植、支气管扩张/肺不张、支气管动脉栓塞和肺功能中度受损（FEV1：62%），她之前在意大利北部接受肺病专家的随访。在汗液检查结果临界后，她被转诊到维罗纳 CF 中心，在那里她的光学β-肾上腺素能汗液试验和肠道电流测量（ICM）均显示异常值。这些结果与 CF 的诊断一致。还通过 forskolin 诱导的肿胀（FIS）测定和直肠类器官单层中的短路电流（Isc）在体外进行 CFTR 功能分析。在用 CFTR 调节剂处理后，这两种测定均显示 CFTR 活性显著增加。Western-blot 分析显示在用校正剂处理后，完全糖基化的 CFTR 蛋白增加，与功能分析一致。有趣的是，tezacaftor 与 elexacaftor 一起在没有 CFTR 激动剂 forskolin 的情况下，在稳态条件下挽救了整个类器官的面积。总之，在体外和体内试验中，我们测量了残留功能，在用 CFTR 调节剂体外孵育后显著增强，特别是用 ivacaftor + tezacaftor + elexacaftor，这表明这种组合可能是这种情况下的潜在最佳治疗方法。
