Antibodies to rheumatoid arthritis nuclear antigen (RANA) are detected by immunodiffusion (ID) and immunofluorescence (IF), though reports of the identity of the antigen(s) have been conflicting. In this study it is shown conclusively that ID and IF anti-RANA react with epitopes on Epstein-Barr nuclear antigen 1 (EBNA-1) and that the major epitope detected by immunofluorescence is represented b...

Libraries of monoclonal antibody against nuclear proteins of Drosophila melanogaster have been established recently to investigate nuclear structure and function. Some of the antibodies have been characterized as being directed against the nuclear envelope. Further studies detailed in this paper describe the fate of the nuclear envelope during mitosis. Indirect immunofluorescence staining of wh...

The nuclear import of transcription regulatory proteins appears to be used by the cell to trigger transitions in cell cycle, morphogenesis, and transformation. We have previously observed that the rate at which SV-40 T antigen fusion proteins containing a functional nuclear localization sequence (NLS; residues 126-132) are imported into the nucleus is enhanced in the presence of the casein kina...

The cross-reaction of IgM-rheumatoid factors (IgM-RF) with a cell nuclear antigen has been further investigated by immunofluorescence procedures. This reaction appears to be optimal at pH 8-9, and fails to occur at pH 6.5. No evidence was obtained by immunofluorescence that IgM-RF bound to the cell nuclear antigen fixes complement. It would appear that the nuclear reactivity of IgM-RF may be of...

The Epstein-Barr virus-soluble (S) antigen extracted from RAJI cells was characterized by sucrose gradient centrifugation, gel filtration, and ion-exchange chromatography. The sedimentation coefficient was estimated to be 8.5S corresponding to a molecular weight of 180,000. The S antigen binds to DEAE-A25 ion exchanger from which it can be eluted with 0.3 M NaCl in Tris buffer (pH 7.2). All fra...

Ki-67 is a commercially available mouse monoclonal antibody, which reacts with a nuclear antigen in proliferating cells. The antibody can be used to determine the growth fraction of human tumours in situ and has been shown to be of prognostic importance. In this study it is shown that in interphase cells Ki-67 reacts with an antigen, mainly present in the nucleoli. Confocal scanning laser micro...

Three exceptional cell lines have been tested for the presence of the Epstein-Barr virus genome by nucleic acid hybridization (complementary RNA.DNA) and Epstein-Barr virus-determined nuclear antigen tests. Two lines were derived from Swedish lymphoma cases and one from an African Burkitt-like lymphoma biopsy that was negative for Epstein-Barr virus DNA and the virus-determined nuclear antigen....