Axonemal Localization of the Dynein Component DNAH5 Is Not Altered in Secondary Ciliary Dyskinesia

Abstract

Primary ciliary dyskinesia (PCD) is a heterogeneous genetic disorder characterized by recurrent airway infections and situs inversus in half of affected individuals. Diagnosis currently relies on demonstration of abnormal ciliary ultrastructure or altered ciliary beat. Alterations encountered in secondary ciliary dyskinesia (SCD) caused by inflammation often complicate the diagnostic workup. We have recently shown that in respiratory epithelial cells from PCD patients with outer dynein arm defects the dynein protein DNAH5 is mislocalized and either completely or partially absent from the ciliary axoneme. In this study, we addressed the question whether SCD might affect axonemal DNAH5 localization in respiratory cells. To induce SCD in vitro, we treated primary human respiratory epithelial cell cultures with interleukin-13 (IL-13). Ciliary function and ultrastructure were assessed by high-speed videomicroscopy and transmission electron microscopy, respectively. For in vivo localization of DNAH5, we performed nasal brushing biopsies in patients with evidence of SCD. Expression of DNAH5 was analyzed by immunofluorescence microscopy. IL-13-treated cells showed evidence of SCD. Ciliary beat frequency was significantly reduced and ultrastructural analyses showed axonemal disorganization compared with control cells. High-resolution immunofluorescence studies of respiratory epithelial cells with SCD identified in vitro and in vivo normal axonemal DNAH5 localization. DNAH5 localization is not altered by SCD, indicating a high potential for immunofluorescence analysis as a novel diagnostic tool in PCD. (Pediatr Res 59: [418][419][420][421][422] 2006)

Effect of TH2 cytokines and interferon gamma on beat frequency of human respiratory cilia

“…IL-13 is produced by innate lymphoid cells and TH2 cells and induces several characteristic changes in the asthmatic airway epithelium resulting in subepithelial fibrosis, mucinous metaplasia, altered ciliated cell differentiation and function and an increase in goblet cells (15)(16)(17). Impairment of ciliary function has previously been shown for IL-13 in human cell culture models (15,18). Our data confirm these results.…”

Aberrant epithelial remodeling with impairment of cilia architecture in non-cystic fibrosis bronchiectasis

“…Our previous study demonstrated that the increased expression of CP110 in mucosa from patients with chronic rhino sinusitis (CRS) was associated to the poor ciliation (15). DNAH5 encode for dynein proteins of ciliated airway, and DNAH5 mutations is a common cause of primary ciliary dyskinesia with outer dynein arm defects (16). In this study, we assessed the length of cilia in bronchi and bronchioles and found significantly longer cilia with abnormal expression of ciliogenesis markers (e.g., CP110 and DNAH5) in hyperplasic epithelium as compared to normal lung tissue.…”

“…Total fluorescence intensity (TFI) measurements were performed through multiplying the positive area by MFI and corrected by subtracting the background autofluorescence (15). The low intensity of DNAH5 positive staining was defined as DNAH5 abnormal expression (16).…”

Primary ciliary dyskinesia: a consensus statement on diagnostic and treatment approaches in children

“…This method has been developed and is routinely used at the University Hospital Freiburg (Freiburg, Germany) [34,35,88]. It has been shown that IFM can be used to identify ODA defects, including regional defects within the ciliary shaft [34,35].…”

“…In five of these eight samples, EM was also performed and confirmed an ODA defect. In addition, the IFM method remains unaltered by secondary ciliary abnormalities [88]. Recent work has also shown that antibody-based techniques can diagnose not only ODA but also IDA abnormalities caused by KTU mutations in PCD [21].…”