Document 0176
 DOCN  M9650176
 TI    CD45RO expression on bovine T cells: relation to biological function.
 DT    9605
 AU    Bembridge GP; MacHugh ND; McKeever D; Awino E; Sopp P; Collins RA;
       Gelder KI; Howard CJ; Institute for Animal Health, Compton Laboratory,
       UK.
 SO    Immunology. 1995 Dec;86(4):537-44. Unique Identifier : AIDSLINE
       MED/96165029
 AB    The 180,000 MW isoform of CD45 (CD45RO) has been identified in cattle
       with a novel monoclonal antibody (mAb) (IL-A116). This has allowed a
       more precise analysis of T-cell function in relation to CD45 isoform
       expression. Within the CD4+ and CD8+ T-cell populations, CD45RO+ and
       CD45RO- subsets were evident. Most CD4+ and CD8+ T cells that expressed
       the CD45RO isoform did not express the 220,000 and 205,000 MW isoforms
       recognized by mAb CC76. In contrast, the WC1+, CD2-, CD4-, CD8-, gamma
       delta T-cell receptor (TCR)+ T cells in bovine peripheral blood
       mononuclear cells (PBMC) were all CD45RO+. Monocytes and granulocytes
       were CD45RO+ but B cells were CD45RO-. Sorting experiments with CD4+ T
       cells from an immunized calf demonstrated that proliferative responses
       to ovalbumin (OVA) were entirely within the CD45RO+ subset. Following
       stimulation with concanavalin A (Con A) the CD45RO- subset of CD4+ T
       cells produced transcripts for interleukin-2 (IL-2) but not IL-4 or
       interferon-gamma (IFN-gamma), while the CD45RO+ subset produced mRNA for
       IL-2, IL-4 and IFN-gamma. Biologically active IL-2 was present in
       supernatants from both CD45RO+ and CD45RO-, CD4+ T cells, and IFN-gamma
       protein was identified by ELISA in supernatants from the CD45RO+ subset,
       confirming the production of cytokines implied by polymerase chain
       reaction (PCR). In contrast, sorting experiments with CD8+ T cells from
       animals immune to the protozoan parasite Theileria parva revealed
       substantial numbers of cytotoxic T-lymphocyte precursors in both the
       CD45RO+ and CD45RO- subsets. Thus it appears that although all
       antigenically primed CD4+ T cells remain CD45RO+, and expression of this
       molecule consequently identifies memory cells within PBMC, antigenically
       primed CD8+ T cells down-regulate CD45RO expression after activation.
 DE    Animal  Antigens, CD45/*BLOOD  Base Sequence  Cattle/*IMMUNOLOGY  Cell
       Division/IMMUNOLOGY  CD4-Positive T-Lymphocytes/IMMUNOLOGY  CD8-Positive
       T-Lymphocytes/IMMUNOLOGY  Electrophoresis, Polyacrylamide Gel
       Interferon Type II/BIOSYNTHESIS  Interleukins/BIOSYNTHESIS  Molecular
       Sequence Data  Precipitin Tests  Support, Non-U.S. Gov't  T-Lymphocyte
       Subsets/*IMMUNOLOGY  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).