 We characterized the basis for the follicular lymphoproliferation in transgenic mice bearing a Bcl-2-immunoglobulin (Bcl-2-Ig) minigene representing the t(14;18) of human follicular lymphoma.     ///    Deregulated Bcl-2-immunoglobulin transgene expands a resting but responsive immunoglobulin M and D-expressing B-cell population.. 