Protocol to establish an oviduct epithelial cell line derived from Gallus gallus using Percoll for in vitro validation of recombinant proteins

In vitro validation of therapeutic and recombinant proteins expressed from transgenic chickens is limited by the co-culture of fibroblasts. Here, we present a protocol for isolating pure epithelial cells derived from the magnum tubular glands of the chicken oviduct. We describe steps for preparing solutions and buffers, tissue collection, processing, dissociation, and Percoll density centrifugation to separate the epithelial cells from co-isolated fibroblasts. We then detail procedures for expressing a recombinant IgG antibody in the Percoll-derived epithelial cell line.

[Interferonogenic activity of the strain BH-3 duck hepatitis virus type I (Picornaviridae: Avihepatovirus: Avihepatovirus A)]

INTRODUCTION

Duck viral hepatitis type I (DVH-I) is a poorly studied contagious disease caused by RNA-containing duck (Anatinae) hepatitis virus type I (Picornaviridae: Avihepatovirus: Avihepatovirus A). This infection is widespread in many countries, including Russia, and causes significant damage to industrial duck breeding. The study of interferonogenic activity of its etiologic agent strains is of great importance in solving the problem of developing effective means to control the disease.

MATERIAL AND METHODS

Strain BH-3 of duck hepatitis virus type I isolated from the liver of sick ducklings was used in the study. The strain was adapted to developing 10-12 day old duck embryos, to the cell culture of chicken and duck fibroblasts and deposited in the State Collection of Viruses of the D.I. Ivanovsky Institute of Virology of FSBI «National Research Centre for Epidemiology and Microbiology named after the honorary academician N.F. Gamaleya» of the Ministry of Health of Russia. Experiments were performed using the standard tissue culture method.

RESULTS AND DISCUSSION

Data on the ability of the viral strain BH-3 to induce interferon (IFN) and its sensitivity to the action of exogenous interferon in the culture of duck fibroblasts are presented. It has been shown that the interferonogenic activity of this strain of the hepatitis virus is in direct proportion to the multiplicity of infection. The maximum induction of IFN (1 : 256 CEPD50) was observed at a dose of 1.0 TCD50/cell in 72-96 hrs after inoculation of the cell culture. Exogenous IFN at a dose of 1 : 128 completely suppressed the cytopathic effect and death of duck embryos infected with hepatitis virus at a dose of 100 TCD50/cell.

CONCLUSION

The data obtained allow us to state that the vaccine strain BH-3 of duck hepatitis virus type I has a pronounced interferonogenic activity and sensitivity to the action of exogenous IFN. This may have implications for the development of effective therapeutic agents against DVH-I.

THE KINETICS OF THE INACTIVATION OF THE HEPATITIS VIRUS TYPE I (AVIHEPATOVIRUS, PICORNAVIRIDAE)

Experimental data on the kinetics of the inactivation of the vaccine strain of the duckling hepatitis virus of the type I with increased temperature and aminoethyl ethylenimine are presented. It was shown that the vaccine strain 3M-UNIIP of the hepatitis virus of ducklings of type I was comparatively thermostable at 56°C and sensitive to the action of aminoethyl ethylenimine; the time of complete inactivation of the virus at a final concentration of 0.1% at 37°C was 24 h. The obtained results suggest that aminoethyl ethylenimine can be used as an inactivator in manufacturing inactivated vaccine against viral hepatitis of ducklings of type I.

Update of the GJB2/DFNB1 mutation spectrum in Russia: a founder Ingush mutation del(GJB2-D13S175) is the most frequent among other large deletions

Although mutations in the GJB2 gene sequence make up the majority of variants causing autosomal-recessive non-syndromic hearing loss, few large deletions have been shown to contribute to DFNB1 deafness. Currently, genetic testing for DFNB1 hearing loss includes GJB2 sequencing and DFNB1 deletion analysis for two common large deletions, del(GJB6-D13S1830) and del(GJB6-D13S1854). Here, we report frequency in Russia, clinical significance and evolutionary origins of a 101 kb deletion, del(GJB2-D13S175), recently identified by us. In multiethnic cohort of 1104 unrelated hearing loss patients with biallelic mutations at the DFNB1 locus, the del(GJB2-D13S175) allele frequency of up to 0.5% (11/2208) was determined and this allele was shown to be predominantly associated with profound sensorineural hearing loss. Additionally, eight previously unpublished GJB2 mutations were described in this study. All patients carrying del(GJB2-D13S175) were of the Ingush ancestry. Among normal hearing individuals, del(GJB2-D13S175) was observed in Russian Republic of Ingushetia with a carrier rate of ~1% (2/241). Analysis of haplotypes associated with the deletion revealed a common founder in the Ingushes, with age of the deletion being ~3000 years old. Since del(GJB2-D13S175) was missed by standard methods of GJB2 analysis, del(GJB2-D13S175) detection has been added to our routine testing strategy for DFNB1 hearing loss.

Evolution of the vertebrate claudin gene family: insights from a basal vertebrate, the sea lamprey

Claudins are major constituents of tight junctions, contributing both to their intercellular sealing and selective permeability properties. While claudins and claudin-like molecules are present in some invertebrates, the association of claudins with tight junctions has been conclusively documented only in vertebrates. Here we report the sequencing, phylogenetic analysis and comprehensive spatiotemporal expression analysis of the entire claudin gene family in the basal extant vertebrate, the sea lamprey. Our results demonstrate that clear orthologues to about half of all mammalian claudins are present in the lamprey, suggesting that at least one round of whole genome duplication contributed to the diversification of this gene family. Expression analysis revealed that claudins are expressed in discrete and specific domains, many of which represent vertebrate-specific innovations, such as in cranial ectodermal placodes and the neural crest; whereas others represent structures characteristic of chordates, e.g. pronephros, notochord, somites, endostyle and pharyngeal arches. By comparing the embryonic expression of claudins in the lamprey to that of other vertebrates, we found that ancestral expression patterns were often preserved in higher vertebrates. Morpholino mediated loss of Cldn3b demonstrated a functional role for this protein in placode and pharyngeal arch morphogenesis. Taken together, our data provide novel insights into the origins and evolution of the claudin gene family and the significance of claudin proteins in the evolution of vertebrates.

Gene regulatory networks that control the specification of neural-crest cells in the lamprey

The lamprey is the only basal vertebrate in which large-scale gene perturbation analyses are feasible at present. Studies on this unique animal model promise to contribute both to the understanding of the basic neural-crest gene regulatory network architecture, and evolution of the neural crest. In this review, we summarize the currently known regulatory relationships underlying formation of the vertebrate neural crest, and discuss new ways of addressing the many remaining questions using lamprey as an experimental model.

Postnatal development of the eye in the naked mole rat (Heterocephalus glaber)

The naked mole rat (Heterocephalus glaber) is a subterranean rodent whose eyes are thought to be visually nonfunctional and as such is an ideal animal with which to pursue questions in evolutionary developmental biology. This report is the first in-depth study on the development and morphology of the naked mole rat eye. Using standard histological analysis and scanning and transmission electron microscopy, we describe the structural features of the eye. We further report on the morphological changes that accompany the development of this eye from neonate to adult and compare them with those that occur during mouse eye development. We observed numerous abnormalities in the shape and cellular arrangement of the structures of the anterior chamber, with notable malformations of the lens. Cell proliferation and cell death assays were conducted to investigate the possible causes of lens malformation. We found that neither of these processes appeared abnormal, indicating that they were not responsible for the lens phenotype of the mole rat. In order to investigate the process of lens differentiation, we analyzed the expression of gamma-crystallins using Western blots and immunocytochemistry. At birth, levels of gamma-crystallin appear normal, but soon thereafter, the gamma-crystallin expression is terminated. Absence of detectable gamma-crystallins in adults suggests that there is a gradual degradation and loss of these proteins. The evolutionary factors that could be responsible for the eye morphology of the naked mole rat are discussed. A model for abnormal lens differentiation and the role it plays in the morphogenesis of the rest of the eye in the naked mole rats is proposed.

Maternal transmission of a ring chromosome 15

A 5-year-old boy with Silver-Russell-like phenotype and developmental delay was found to have a ring chromosome 15. The same r(15) was found in his slightly mentally retarded mother with mild dysmorphism. Analysis of the literature showed 34 families with direct vertical transmission of a ring autosome. In 30 of these families abnormal chromosomes were inherited from the mothers; both maternal and paternal transmission was shown in different generations of one family; and only in 3 families ring chromosomes were inherited from the fathers. The possible explanations of preponderance of maternal transmission are briefly discussed.

[Role of the pulmonary surfactant in the pathogenesis of bronchial asthma]

The submitted data from the published literature coupled with findings from the authors' own investigations underline the importance of the part that disturbances in the system of the pulmonary surfactant have in the pathogenesis of bronchial asthma. This permits regarding the substitution surfactant therapy with exogenous surfactants as a pathogenetically validated treatment modality for bronchial asthma as evidenced by the first positive results of its employment.