CD1D and B-cell chronic lymphocytic leukemia: CD1d is also broadly expressed in various B cell chronic lymphoproliferative disorders (B-CLPDs): CD1d expression on leukemic B cells in chronic lymphocytic leukemia (CLL) is generally lower than on other B-CLPDs (such as mantle cell lymphoma) [5], but elevated CD1d expression in CLL has been associated with the presence of unmutated immunoglobulin variable region genes [6] and poor prognosis [7], suggesting its potential utility as a biomarker for this disease.