Document 0056
 DOCN  M9590056
 TI    C3d and Epstein-Barr virus (CR2/CD21 ligands) stimulate cells of an
       HTLV-I line, MT-2.
 DT    9509
 AU    Kuraya M; Sato T; Fujita T; Department of Biochemistry, Fukushima
       Medical College, Japan.
 SO    Microbiol Immunol. 1995;39(2):145-51. Unique Identifier : AIDSLINE
       MED/95303033
 AB    We studied the physiological role of complement receptor type II (CR2,
       C3d/EBV receptor) expressed on T cells using MT-2 cells. First, we
       confirmed CR2 expression on MT-2 cells by flow cytometry and found that
       the MW of CR2 molecules on these cells and Raji B cells were the same by
       SDS-PAGE analysis. When MT-2 lysates were incubated with anti-CR2 mAb
       HB5 and thereafter with 32P-labeled ATP, 52- and 74-kDa proteins were
       phosphorylated, suggesting the activation of MT-2 cells through the
       complex of CR2 with these proteins. In this respect, we measured
       lymphotoxin production by MT-2 cells when incubated with C3d or EBV. The
       cytotoxicity of the MT-2 supernatant against L929 cells was elevated in
       a dose- and time-dependent manner. Next, we confirmed EBNA expression on
       EBV-infected MT-2 cells and attempted to establish an EBV-positive MT-2
       clone by in vitro EBV infection. However, these clones disappeared
       during cloning. To clarify this mechanism, we examined the EBV genome in
       MT-2 cells. By Southern blot analysis, BamHI digestion of DNA extracts
       from MT-2 cells 3 days after EBV treatment gave a 3.0-kb signal which
       comigrated with the EBV BamHI-W probe. The 3.0-kb signal of genomic
       EBV-DNA was detected at 1, 2, 3, 5, and 7 days after EBV treatment, but
       could not be detected at 14 days. Thus, natural ligands of CR2 stimulate
       CR2-positive MT-2 cells through their functionally active CR2 molecules
       and in vitro EBV infection of MT-2 cells might be transient.
 DE    Animal  Antigens, Viral/BIOSYNTHESIS  Cell Line  Cytotoxicity,
       Immunologic  DNA-Binding Proteins/BIOSYNTHESIS  Electrophoresis,
       Polyacrylamide Gel  Fibroblasts/MICROBIOLOGY  Flow Cytometry
       Herpesvirus 4, Human/GROWTH & DEVELOPMENT/*PHYSIOLOGY
       HTLV-I/*PHYSIOLOGY  Ligands  Lymphotoxin/BIOSYNTHESIS  Mice
       Phosphorylation  Receptors, Complement 3d/*PHYSIOLOGY
       T-Lymphocytes/MICROBIOLOGY/*PHYSIOLOGY  Tumor Cells, Cultured  JOURNAL
       ARTICLE

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