Genetic aspects of immotile cilia syndrome

The genetics of the immotile cilia syndrome has been analyzed in a series of 46 affected individuals from 38 families. Both sexes were equally affected: there were 20 males and 26 females in this series. All patients had upper and lower respiratory disease with chronic sinusitis, otitis, and chronic cough from early childhood. Bronchiectasis was common in older children and adults. Situs inversus occurred randomly, affecting 11 males and 15 females. Biopsies of nasal and bronchial mucosa from these subjects have been investigated by electron microscopy and identified as having specific ultrastructural defects of respiratory tract cilia including deficiencies in outer dynein arms (19), inner dynein arms (3), both inner and outer dynein arms (15), radial spoke defect (5); and microtubular transposition anomaly (4). Segregation analysis of proband sibships was consistent with autosomal recessive inheritance. However, the different ultrastructural defects that underly the immotile cilia syndrome involve presumably different genetic determinants, and the different types have not been analyzed separately. Examination of paternal age and birth order gave no evidence of new autosomal dominant mutation in the series.     

Cystic fibrosis mutations and immotile cilia syndrome

The immotile cilia syndrome (ICS) presents with autosomal recessive inheritance and is a chronic respiratory disease supposed to be caused by different genetic determinants. The hypothesis that cystic fibrosis (CF) heterozygotes may have a predisposition to develop bronchial or respiratory diseases other than CF prompted us to look for CF mutations in patients with ICS. Five patients, as well as the parents and two healthy brothers of one patient were tested for 12 CF mutations, for the polymorphic GATT repeat in intron 6a and for the CF gene flanking markers XV-2c, KM19, MP6d-9, J3.11. None of the 12 mutations at the CF locus have been detected in the ICS patients and no linkage was found between ICS and the polymorphic markers. Thus, based on our data, ICS and CF seem to be two different clinical entities.     

Ultrastructure of respiratory cilia of WIC-Hyd male rats. An animal model for human immotile cilia syndrome.

The WIC-Hyd rat is a mutant from the Csk: Wistar-Imamichi rat, with spontaneous hydrocephalus. In male rats, the hydrocephalus is severe and about one half of hydrocephalic male littermates possess situs inversus totalis. Ependymal cilia in these animals are immotile, and this defect is regarded as a mechanical cause of hydrocephalus. This paper presents the ultrastructural features of respiratory cilia in these rats in comparison with those in human immotile cilia syndrome. The respiratory cilia in these rats also are immotile and the dynein arms are missing, as in human cases. Previously only eight dogs with immotile cilia syndrome and a mutant hydrocephalic-polydactyl mouse were reported with respect to these phenomena. However the WIC-Hyd rat is the first useful animal model for human immotile cilia syndrome, and further studies may serve to clarify the genetic background of this condition.     

Usher syndrome type I associated with bronchiectasis and immotile nasal cilia in two brothers.

Usher syndrome type I is an autosomal recessive disease characterised by congenital sensorineural deafness, involvement of the vestibular system, and progressive visual loss owing to retinitis pigmentosa. Here we report the association of this disease with bronchiectasis, chronic sinusitis, and reduced nasal mucociliary clearance in two sibs and we suggest Usher syndrome type I could be a primary ciliary disorder.     

Absence of cilia and basal bodies with predominance of brush cells in the respiratory mucosa from a patient with immotile cilia syndrome

This report describes the ultrastructural alterations observed in the tracheal epithelium of a 13-year-old male with a history of recurrent pneumonia, chronic bronchitis, chronic otitis media, and situs inversus. The epithelium consisted of globlet and basal cells with many columnar cells that lacked cilia and basal bodies. The surface of these cells had regular microvilli and cytoplasmic features typical of brush cells.     

Ultrastructural abnormalities of cilia in the human respiratory tract

Primary ciliary dyskinesia is thought to be caused by a primary defect of ciliary ultrastructure and function. However, atypical cilia have also been described in humans with and without acquired respiratory tract disease. With few exceptions, these abnormalities have not been quantified. Ciliary ultrastructure was therefore studied in 21 specimens of bronchial mucosa from patients with a variety of respiratory problems and in five specimens of nasal mucosa from asymptomatic nonsmokers. The incidence of microtubular abnormalities and compound cilia was generally less than 10 per cent, and there was no correlation between the incidence of these abnormalities and the presence of lung carcinoma or smoking habits. Transposition of ciliary microtubules and radial spoke defects, specific microtubular abnormalities thought to be pathognomonic for primary ciliary dyskinesia, were observed in a number of specimens, and visualization of dynein arms, particularly inner dynein arms, was extremely difficult. It is concluded that ultrastructural abnormalities of cilia should be carefully quantified in patients with primary ciliary dyskinesia and control subjects before it can be assumed they have pathologic significance.     

Ultrastructural morphometry in the diagnosis of Sézary syndrome

Blood specimens from 87 patients and control subjects were prepared for electron microscopy and subjected to ultrastructural morphometric evaluation by using a computerized planimeter. A statistical comparison of means indicated that patients with Sézary syndrome could be distinguished from normal subjects and patients with reactive lymphocytosis, by using mean nuclear perimeter and form factor values. The lymphocytic nuclei from patients with infectious mononucleosis were more lobated on visual inspection than those from normal subjects; the difference in mean form factor values was statistically significant. The simple histogram method was most discriminatory and distinguished patients with Sézary syndrome from patients with other types of lymphoid leukemias and reactive lymphocytosis, including infectious mononucleosis. The histogram method could not, however, distinguish patients with Sézary syndrome from patients with T-cell chronic lymphocytic leukemia and Japanese T-cell leukemia. The use of bivariate graphic displays (plotting nuclear size and shape measurements) placed the lymphoid cells of the various types of lymphoproliferative disorders into distinct morphometric domains. Computerized morphometric techniques may, therefore, be of greater value when the range of possible diagnoses is large.     

Ultrastructural observations on morphogenesis of atypical cilia

Though ultrastructural studies of bronchial epithelium both in man and in experimental animals revealed in a variety of conditions the presence of pathologically altered cilia, little is known about their genesis and significance. In this work we have described the alterations noticed in ciliary morphology during the formation of atypical cilia. A probable mechanism for their production is also proposed on the basis of our results.     

Ultrastructural changes in bronchial epithelial cilia in chronic pulmonary inflammation in children

Bronchial mucosal biopsy specimens from 40 children aged 6 to 14 years were examined, including 35 children with chronic pneumonia and 5 in whom the inflammatory process was consequent to bronchopulmonary developmental abnormalities. The ultrastructural changes revealed in the cilia are described in detail.     

Ultrastructural defects of respiratory tract cilia associated with chronic infections

Ultrastructural defects were demonstrated in nasal and bronchial cilia from a 12-year-old boy with repeated upper and lower respiratory tract infections. Numerous abnormalities were found, including single axonemes surrounded by excess cytoplasmic matrix, compound cilia, intracytoplasmic microtubular doublets, and cilia contained within a periciliary sheath. Dynein arms were missing from the majority of the peripheral microtubular doublets. The most striking abnormality, however, was a disorientation of cilia as judged by the increased variation in the orientation of central microtubules. Because of these ultrastructural abnormalities, it is highly likely that ciliary motility was markedly decreased and that defective mucociliary transport was responsible for chronic and repeated upper respiratory tract infections.     

Different fertilization rates between immotile testicular spermatozoa and immotile ejaculated spermatozoa for ICSI in men with Kartagener's syndrome: case reports

We report two cases of infertility treatment in couples where males suffered from Kartagener's syndrome (KS) and a total absence of motile sperm in the ejaculate. A total of three ICSI cycles was carried out. In all cycles, viable ejaculated or testicular spermatozoa were selected using the hypo-osmotic swelling (HOS) test. Case 1: In the first ICSI cycle total fertilization failure occurred after using ejaculated spermatozoa. In the following cycle testicular spermatozoa were used for ICSI, resulting in 75% fertilized oocytes and a pregnancy. Case 2: In the same ICSI cycle 50% of the oocytes were injected with ejaculated and 50% with testicular spermatozoa. The fertilization rates were 44 and 56% respectively and high quality embryos were achieved in both groups. One single embryo derived from testicular sperm was transferred with a resulting singleton pregnancy. In conclusion, testicular sperm for ICSI seem to have reliable fertilization capacity in men with KS, while ejaculated sperm, even if tested viable, seem more unpredictable. HOS test for selection of viable sperm for ICSI is recommended when ejaculated as well as testicular sperm are used for ICSI.     

Ultrastructural and immunohistochemical study of the basal apparatus of solitary cilia in the human oviduct epithelium

The basal apparatus of the solitary cilium is composed of the basal body, an associated centriole and the basal body‐associated structures. To see the connection between the basal body and the centriole, we studied the basal apparatus of solitary cilia in human oviductal secretory cells by electron microscopy and immunohistochemistry. A single centriole was present in the vicinity of the basal body of a solitary cilium. The basal body and the single centriole were interconnected by one or two bundles of thin filaments with a few periodic striations. We have called these bundles the striated connector. The periodicity of striations in the striated connector measured 55 ± 6 nm, about 15 nm shorter than that of striated rootlets. The striated connector was immunolabelled with R67 antibody specific to striated rootlets, indicating that they are composed of common molecule(s). Although the true function of the connector is unknown as yet, it could play an important role for stabilising the basal body in the apical cytoplasm.     

Ultrastructural characterization of primary cilia in pathologically characterized human glioblastoma multiforme (GBM) tumors

Background

Primary cilia are non-motile sensory cytoplasmic organelles that are involved in cell cycle progression. Ultrastructurally, the primary cilium region is complex, with normal ciliogenesis progressing through five distinct morphological stages in human astrocytes. Defects in early stages of ciliogenesis are key features of astrocytoma/glioblastoma cell lines and provided the impetus for the current study which describes the morphology of primary cilia in molecularly characterized human glioblastoma multiforme (GBM) tumors.

Methods

Seven surgically resected human GBM tissue samples were molecularly characterized according to IDH1/2 mutation status, EGFR amplification status and MGMT promoter methylation status and were examined for primary cilia expression and structure using indirect immunofluorescence and electron microscopy.

Results

We report for the first time that primary cilia are disrupted in the early stages of ciliogenesis in human GBM tumors. We confirm that immature primary cilia and basal bodies/centrioles have aberrant ciliogenesis characteristics including absent paired vesicles, misshaped/swollen vesicular hats, abnormal configuration of distal appendages, and discontinuity of centriole microtubular blades. Additionally, the transition zone plate is able to form in the absence of paired vesicles on the distal end of the basal body and when a cilium progresses beyond the early stages of ciliogenesis, it has electron dense material clumped along the transition zone and a darkening of the microtubules at the proximal end of the cilium.

Conclusions

Primary cilia play a role in a variety of human cancers. Previously primary cilia structure was perturbed in cultured cell lines derived from astrocytomas/glioblastomas; however there was always some question as to whether these findings were a cell culture phenomena. In this study we confirm that disruptions in ciliogenesis at early stages do occur in GBM tumors and that these ultrastructural findings bear resemblance to those previously observed in cell cultures. This is the first study to demonstrate that defects in cilia expression and function are a true hallmark of GBM tumors and correlate with their unrestrained growth. A review of the current ultrastructural profiles in the literature provides suggestions as to the best possible candidate protein that underlies defects in the early stages of ciliogenesis within GBM tumors.