Sodium Dodecyl Sulfate Polyacrylamide Gel Electropheresis Research Articles

Evolution of tissue damage in compressive spinal cord injury in rats.

The evolution of tissue damage in compressive spinal cord injuries in rats was studied using an immunohistochemical technique and by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The rupture of small vessels accompanied by intense tissue permeation of serum components in and around the hemorrhagic foci appeared to be immediate consequences of the mechanical insult. The loss of cell membrane integrity in neural elements became evident within 1 hour after injury as shown by the diffuse albumin-immunoreactivity of the cytoplasm. At the site of mechanical insult, approximately 30% of the neurofilament proteins were degraded within 1 hour, and 70% of them were lost within 4 hours after injury. A large number of cells positive for glial fibrillary acidic protein were found to demarcate the injured tissue within 1 hour after injury. The progression of tissue damage largely subsided within 48 hours. One week after injury, severe degeneration of the ascending tracts in the posterior funiculus was shown clearly by axon staining and less convincingly by myelin staining. Secondary degeneration of the corticospinal tract in distal segments remained inconspicuous for up to 3 months.

K23. A low-incidence antigen in the Kell blood group system identified by biochemical characterization.

An antibody in the serum of a gravida 4, para 3 woman reacted with red cells from two of her children, her husband, and his mother, but with none of more than 2100 reference red cell samples and blood samples from donors. The reactive antigen was inactivated by 2-aminoethylisothiouronium bromide or dithiothreitol-papain treatment. The antigen was immunoprecipitated from paternal red cells with maternal antibody and shown to migrate by sodium dodecylsulfate polyacrylamide gel electropheresis as a single protein of approximately 93,000 daltons. After transfer to nitrocellulose paper by Western blotting, the protein reacted with a rabbit antibody specific for Kell protein. The chemical inactivation and electrophoretic findings were characteristic of Kell group antigens. The reaction with the rabbit antibody establishes that the "new" low incidence antigen was an epitope on Kell group protein and must be coded for by the Kell gene. It has been designated K23.