       Document 0986
 DOCN  M9620986
 TI    Th1 and Th2 help for B cells: differential capacity for induction of
       autonomous responsiveness to IL-2.
 DT    9602
 AU    Poudrier J; Owens T; Department of Medicine, McGill University,
       Montreal, Quebec,; Canada.
 SO    Int Immunol. 1995 Jun;7(6):1021-7. Unique Identifier : AIDSLINE
       MED/96082369
 AB    Sustained interaction with Th1 cells has been shown to induce IL-2
       responsiveness by murine B cells. This is equivalently dependent on
       CD40, CD54/ICAM-1 and MHC II ligation, and co-cross-linking of CD54 and
       MHC II in the presence of IL-5 up-regulates a functional IL-2R on B
       cells. We now show that IL-5 (125 U/ml) synergizes with Th1 cells to
       induce B cell responses to IL-2, that are maintained following T-cell
       removal, e.g. autonomous. Th1 help in the absence of IL-5 resulted in
       weak or undetectable responses following T cell removal. The mechanism
       of IL-5 synergy involved persistence of IL-2R beta expression following
       T cell removal, as opposed to enhancement of IL-2R induction or
       function. The level of contact-induced IL-2R expression on B cells was
       not itself modified by IL-5. The effects of IL-5 did not overcome the
       requirement for T contact signals and treatment of B cells with soluble
       anti-Ig did not circumvent the need for IL-5 for autonomous IL-2
       responses. Consistent with the above, interaction with an IL-5-producing
       Th2 clone induced strong autonomous B cell responses to IL-2.
       Qualitative differences of Th2 help over that of Th1 may thus be
       attributable to their differential ability to induce autonomous B cell
       responsiveness to cytokines. This may be representative of events in
       which maintenance of cell cycle is important, as is the case in germinal
       centers.
 DE    Animal  B-Lymphocytes/*IMMUNOLOGY/METABOLISM  Cells, Cultured
       Comparative Study  Drug Synergism  Female  Immunoglobulins,
       Surface/PHARMACOLOGY  Interleukin-2/*PHARMACOLOGY
       Interleukin-5/PHARMACOLOGY  Lymph Nodes/IMMUNOLOGY  *Lymphocyte
       Cooperation  Lymphocyte Transformation  Mice  Mice, Inbred BALB C  Mice,
       Inbred C57BL  Receptors, Interleukin-2/METABOLISM  Support, Non-U.S.
       Gov't  Th1 Cells/*IMMUNOLOGY  Th2 Cells/*IMMUNOLOGY  JOURNAL ARTICLE

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

