Document 0155
 DOCN  M95A0155
 TI    The role of superantigens in the immunobiology of retroviruses.
 DT    9510
 AU    Huber BT; Beutner U; Subramanyam M; Department of Pathology, Tufts
       University School of Medicine,; Boston, MA 02111, USA.
 SO    Ciba Found Symp. 1994;187:132-40; discussion 140-3. Unique Identifier :
       AIDSLINE MED/95317139
 AB    Murine mammary tumour viruses (MMTVs) are retroviruses that encode
       superantigens capable of stimulating T cells via superantigen-reactive T
       cell receptor V beta chains. MMTVs are transmitted to the suckling
       offspring via the milk. We have established that class II and B
       cell-deficient mice that were foster nursed by virus-secreting mice do
       not transfer infectious MMTVs to their offspring. No MMTV proviruses
       could be detected in the spleen and mammary tissue of these mice and
       there was no deletion of MMTV superantigen-reactive T cells. These
       results confirm that superantigen expression in the context of MHC class
       II molecules is required for MMTV transmission. We conclude that B cells
       are essential for the completion of the viral life cycle in vivo. This
       indicates that B cells are infected first and that viral amplification
       takes place only if infected B cells present the MMTV superantigen on
       their surface which, in turn, results in activation of T cells
       expressing the appropriate T cell receptor V beta chains. These
       activated T cells stimulate B cells which enables viral replication.
       Human T cells carry all the structural features required for an
       efficient response to murine retrovirally encoded superantigens.
       Superantigen-like stimulation of human T cells has been demonstrated in
       both infectious and autoimmune diseases. Human immunodeficiency virus
       may encode a superantigen but this has not been proven.
 DE    Animal  Antigens, Viral/GENETICS/*IMMUNOLOGY/PHYSIOLOGY  Genes, Viral
       Genetic Code  Human  Mammary Tumor Viruses, Mouse/GENETICS/*IMMUNOLOGY
       Mice  Superantigens/GENETICS/*IMMUNOLOGY/PHYSIOLOGY  Support, U.S.
       Gov't, P.H.S.  JOURNAL ARTICLE  REVIEW  REVIEW, TUTORIAL

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