Intranasal administration of plasmid DNA nanoparticles yields successful transfection and expression of a reporter protein in rat brain.

Viral vectors are a commonly used method for gene therapy because of their highly efficient transduction of cells. However, many vectors have a small genetic capacity, and their potential for immunogenicity can limit their usefulness. Moreover, for disorders of the central nervous system (CNS), the need for invasive surgical delivery of viruses to the brain also detracts from their clinical applicability. Here, we show that intranasal delivery of unimolecularly compacted DNA nanoparticles (DNA NPs), which consist of single molecules of plasmid DNA encoding enhanced green fluorescent protein (eGFP) compacted with 10 kDa polyethylene glycol (PEG)-substituted lysine 30-mers (CK30PEG10k), successfully transfect cells in the rat brain. Direct eGFP fluorescence microscopy, eGFP-immunohistochemistry (IHC) and eGFP-ELISA all demonstrated eGFP protein expression 2 days after intranasal delivery. eGFP-positive cells were found throughout the rostral-caudal axis of the brain, most often adjacent to capillary endothelial cells. This localization provides evidence for distribution of the nasally administered DNA NPs via perivascular flow. These results are the first report that intranasal delivery of DNA NPs can bypass the blood-brain barrier and transfect and express the encoded protein in the rat brain, affording a non-invasive approach for gene therapy of CNS disorders.

The fine structure of the camel prostate gland.

The prostate glands of 10 mature camels (3-5 years of age) were studied with the transmission electron microscope. Ultrastructural examination of the secretory acini showed 2 types of cells, i.e. tall secretory epithelial cells and basal cells. The cells both were characterised by rounded nuclei. The subnuclear cytoplasm was filled with abundant stacks of rough endoplasmic reticulum (RER). The RER was occasionally observed to be interconnected with whorls and networks of smooth endoplasmic reticulum (SER). In the supranuclear region, a moderate Golgi complex and a large number of secretory granules of varying sizes and electron density were observed. Lysosomes of various sizes were present in all types of cells. The luminal surfaces of the cells were covered with large number of microvilli. The basal cells were described. The ultrastructural morphology of the secretory units of the camel prostate may help us to determine if the mode of secretion in the camel prostate is apocrine in nature.

Electron microscopic studies on the thymus of the Arabian camel (Camelus dromedarius).

The thymus of young camels contained 2 main cell types: lymphocytes and epithelial reticular cells (ER). 3 types of ER cells were observed and described. 2 types from these cells showed secretory activities, meanwhile, the third type had well developed tonofilaments. Hassall's corpuscles were noted in the medulla and were composed of degenerative concentrically arranged ER cells. The functional morphology of the above mentioned structures was discussed.

Ultrastructure of the camel monocyte.

The fine structure of the camel monocytes was studied in order to record its constituents because these informations were missed from the literature. The observations revealed the presence of a few short cisternae of rough endoplasmic reticulum and various forms of vesicles associated with the Golgi complex which were seen near the mitochondria. The distribution of the cytoplasmic organelles seemed to be located adjacent to the main indentation in the nuclei. Camel monocytes were found to possess microvilli of varying length and number. The functional morphology of the above mentioned structures was discussed.