       Document 0335
 DOCN  M9640335
 TI    Up-regulation of IL-2 receptor alpha and MHC class II expression on
       lymphocyte subpopulations from bovine leukemia virus infected
       lymphocytotic cows.
 DT    9604
 AU    Stone DM; Hof AJ; Davis WC; Department of Veterinary Microbiology and
       Pathology, Washington; State University, Pullman 99164-7040, USA.
 SO    Vet Immunol Immunopathol. 1995 Sep;48(1-2):65-76. Unique Identifier :
       AIDSLINE MED/96107003
 AB    Infection with bovine leukemia virus (BLV) leads to a persistent
       lymphocytosis (PL) characterized by a marked increase in circulating B
       lymphocytes that express the orthologue of CD5. To gain insight into the
       factors accounting for lymphocytosis, experiments were conducted to
       determine the functional activation status of lymphocytes from BLV
       seronegative and BLV infected aleukemic cows with PL. Stimulation with
       the B lymphocyte mitogen Staphylococcus aureus Cowan strain I (SAC),
       recombinant human interleukin-2 (rIL-2), or pokeweed mitogen (PWM), a T
       lymphocyte-dependent B lymphocyte mitogen, revealed differences in the
       pattern of expression of IL-2 receptor alpha (IL-2R alpha) and major
       histocompatibility (MHC) class II molecules on B and T lymphocytes from
       uninfected and BLV infected PL cows. rIL-2 induced expression of IL-R
       alpha on B lymphocytes from PL cows but not B lymphocytes from BLV
       seronegative cows. SAC alone, or in combination with rIL-2, had no
       effect on B lymphocytes from BLV seronegative cows. However, rIL-2 alone
       or in combination with SAC induced expression of IL-2R alpha on B
       lymphocytes from PL cows. PWM stimulated expression of IL-2R alpha on
       bovine B lymphocytes regardless of BLV status, and induced a
       significantly higher level of expression on B lymphocytes from PL cows.
       Mitogens and rIL-2 had a similar stimulatory effect on induction of
       IL-2R alpha expression on CD4 T lymphocytes regardless of BLV status.
       Only PWM induced expression of IL-2R alpha on bovine CD8 T lymphocytes
       and induced a significantly higher level of expression on this T
       lymphocyte subset from PL cows. Examination of freshly isolated B
       lymphocytes from PL cows revealed increased spontaneous expression of
       the MHC class II molecule compared to B lymphocytes from control cows.
       None of the culture conditions examined induced MHC-II expression on CD4
       and CD8 T lymphocytes from BLV seronegative cows. In contrast, SAC+IL-2
       and PWM induced MHC-II expression on CD4 and CD8 T lymphocytes from BLV
       infected PL cows, resulting in a significantly greater proportions of
       these lymphocyte subsets expressing this molecule compared to CD4 and
       CD8 T lymphocytes from control cows. The data indicate that infection
       with BLV affects the response of B and T lymphocytes to signals of
       activation, up-regulating the expression of surface molecules involved
       in both direct contact and cytokine-mediated T lymphocyte-dependent B
       lymphocyte activation.
 DE    Animal  B-Lymphocytes/METABOLISM  Cattle  Enzootic Bovine
       Leukosis/*IMMUNOLOGY  Female  Histocompatibility Antigens Class
       II/*BIOSYNTHESIS  Immunophenotyping  Leukemia Virus,
       Bovine/*IMMUNOLOGY/ISOLATION & PURIF  Lymphocyte
       Subsets/CLASSIFICATION/*IMMUNOLOGY/*METABOLISM  Receptors,
       Interleukin-2/*BIOSYNTHESIS  T-Lymphocytes/METABOLISM  Up-Regulation
       (Physiology)/*IMMUNOLOGY  JOURNAL ARTICLE

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

