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Notes: Summary Werner syndrome (WS) is caused by mutations in the gene encoding RecQ type DNA helicase (WRN). We report a 53-year-old Japanese male with WS who initially presented with skin ulcers on the feet and the left elbow. The patient had a high-pitched voice, hoarseness, a characteristic bird-like facial appearance with a beak-shaped nose, canities and juvenile cataracts. Immunoblot analysis using a monoclonal antibody directed against the WS gene product DNA helicase revealed that the patient's leucocytes lacked this particular molecule, confirming the diagnosis of WS. This new immunoblot system therefore enables the diagnosis of WS to be made without the need to undertake more complex mutational analysis.

Notes: Summary Intradermally injected DNA diffuses into the epidermis and can then enter keratinocytes and become expressed by these cells. Using this method, plasmids containing cytokine genes that have been introduced into keratinocytes can induce a level of cytokine expression sufficient to provide biological effects in the treated skin. Furthermore, transgenic cytokines released from the transduced keratinocytes can also enter the circulation and have downstream effects on other target organs. Thus far, naked DNA injection appears to be a safe, simple, and relatively efficient method that enables genes to be expressed in transplanted human skin on immunosuppressed animals. In humans, keratinocyte gene therapy using the cytokine gene DNA injection method has the potential to become a powerful therapeutic tool for dermatologists in the management of certain inflammatory and other dermatoses.

Notes: Background Fabry disease results from a genetic deficiency of α-galactosidase A (GLA) activity. Phenotype–genotype correlations in this condition have not as yet been fully elucidated. Objectives To report a case of a male patient with classical Fabry disease and his mother, a heterozygous female with Fabry disease, showing cardiac involvement, and to identify the underlying GLA gene mutation in this particular phenotype. Patients/methods Genomic DNA was extracted from the patient, his mother and the unaffected family members. Biopsy specimens of skin, heart and kidney were examined using light and electron microscopy. The mutation was identified by polymerase chain reaction and direct sequencing and was confirmed by restriction enzyme fragment length polymorphism. Results The G→C transversion was identified in codon 97 of the GLA gene and resulted in an A97P amino acid substitution that was a novel pathogenic GLA gene mutation. The male patient who had classical Fabry disease was hemizygous and his mother was heterozygous for this mutation. Conclusions These results indicate that the A97P amino acid substitution in GLA might tend to induce classical Fabry disease.

Notes: Summary Background Cornified cell envelope (CCE) formation is an important step in the final stage of keratinization, in which CCE precursor proteins including involucrin and loricrin are cross-linked by keratinocyte transglutaminases (TGases) to the inner surface of the plasma membrane of cornified cells, while the outer surface is coated with material derived from secreted lamellar granules. Objectives Skin samples from human fetuses of a series of estimated gestational age (EGA) (49–163 days) were studied for the prescence of precursor proteins. Methods TGase activity was studied by in situ TGase activity assay, and ultrastructural features of CCE formation were observed at each stage of hair follicle development. We used immunofluorescent labelling to investigate the time and site of expression of CCE precursor proteins involucrin and loricrin, TGases 1, 2 and 3, and a 25-kDa lamellar granule-associated protein (LGP) in developing human hair follicles. Results In the hair germ (65–84 days EGA) (corresponding to the stages 1–2 of murine hair follicle morphogenesis), only TGase 2 was observed in the entire hair germ, where in situ TGase activity was weakly positive, although thickening of cell membrane was not seen ultrastructurally. In the hair peg (85–104 days EGA) (corresponding to the stage 3 of murine hair follicle morphogenesis), loricrin and TGase 2 were seen in cells of the upper part of the hair peg while TGase 1, 3 and LGP were observed in the inner cells of the hair peg. In situ TGase activity was weakly positive in the upper part and inner cells of the hair peg. In the bulbous hair peg (105–135 days EGA) (corresponding to the stages 4–6 of murine hair follicle morphogenesis) and differentiated lanugo hair follicle (〉 135 days EGA) (corresponding to the stages 7–8 of murine hair follicle morphogenesis), immunoreactivities of involucrin, loricrin, TGase 1, 2, 3, in situ TGase activity and LGP were detected in the inner root sheath cells, hair canals and inner cells of the outer root sheath in the region of the isthmus. Ultrastructurally, thickening of cell membrane was already seen in the inner root sheath cells of the bulbous hair peg and electron-dense, thick CCE was observed in the hair cuticle and hair canal of differentiated lanugo hair follicle. Conclusions These data indicate that, in terms of CCE formation, certain portions of the developing human hair follicle have already been determined in differentiation of the hair canal and cuticle at the hair peg stage.