Modification of DNA patterns in plasma and nucleated blood cells from systemic sclerosis patients.

OBJECTIVE: To analyze the DNA patterns extracted from plasma and nucleated blood cells (lymphocytes) in systemic sclerosis (SSc) with a new MFC DNA extracting kit. METHODS: Ten SSc patients and 9 healthy controls were studied. Heparin containing blood samples were separated into plasma and buffy coat fractions and subjected to DNA extraction. The DNA pattern was revealed by 0.4% agarose electrophoresis and analyzed in a Gelblot Programme file (UVP Product). RESULTS: In control samples the DNA pattern observed in plasma extract was different from that of the buffy coat. For the plasma a series of peaks ranging from 2-23 Kb were present, and for the buffy coat we usually observed 2 to 3 principle bands, respectively, at around 33 Kb and 0.5 Kb. For SSc patients the DNA patterns that resulted from the plasma and buffy coat were totally different from the control samples, with some exceptions. CONCLUSION: We observed that SSc samples contain a distinctively different DNA pattern compared to healthy controls. Further studies are needed to establish whether or not this DNA pattern might be considered peculiar to SSc, and whether or not the method is a useful tool for pathogenic studies of the disease and for diagnostic purposes

Neurotrophins are required for nerve growth during development

Although the requirement of neurotrophins for the prevention of cell death in the peripheral nervous system is well established, their physiological involvement in nerve growth is still unclear. To address this question, we generated a mouse that expresses the green fluorescent protein in post-mitotic neurons, allowing the repeated visualization of all motor and sensory axons during development. We imaged the growth of these axons into the limb bud of day 10.5 embryos. Sensory axons, but rarely motor axons, were targeted to ectopically placed beads containing any of the neurotrophins NGF, BDNF, NT-3 or NT-4/5. Conversely, a combination of function-blocking monoclonal antibodies to NGF, BDNF and NT-3 dramatically inhibited elongation of both sensory and motor axons in the limb bud, indicating that the growth of mixed nerves is dependent upon neurotrophins during development