Relationship between CD4+/CD8+ T cell ratio and T cell activation in multiple myeloma: reference to IL-16

Abstract We found that the ratio of CD4 + to CD8 + T cells (CD4/CD8 ratio) was decreased in patients with multiple myeloma (MM) and that this decrease was significantly related to an increase of human leukocyte antigen (HLA)-DR expression by CD8 + (but not CD4 + ) T cells ( P P + T cells in MM may be mediated by activation of CD8 + T cells derived cytokine IL-16. In addition, these T cell phenotypic changes and the IL-16 level appear to be useful indicators of disease activity.