T-cell imbalances in patients with multiple myeloma: an analysis by monoclonal antibodies.

Abstract

Functionally distinct human T-lymphocyte subpopulations have recently been defined by monoclonal antibodies, recognizing cell surface differentiation antigens expressed as distinct populations of T cells. We determined the proportions and absolute numbers of T-cell subsets in 24 patients with multiple myeloma. These patients exhibited in the peripheral blood significantly decreased proportions of T3-positive cells (63.13±17.6 vs 79.70±7.07% of the normal controls;P<0.0005), significantly decreased proportions of T4-positive cells (39.13±13.01 vs 54.55±5.30% of the normal controls;P<0.0005), and moderately increased proportions of T8-positive cells (37.21±13.70 vs 29.90±4.87% of the normal controls;P<0.029). Furthermore, we observed in these patients significantly decreased absolute numbers of peripheral blood lymphocytes (1240.00±577.80 vs 2185.70±955.43 of the normal controls;P<0.001), T3-positive (950.05±590.23 vs 1732.25±771.60;P<0.0005), and T4-positive cells (434.04±155.95 vs 1182.50±490.96;P<0.0005). In contrast, the absolute numbers of T8-positive cells were normal (584.22±456.17 vs 662.15±369.20 of the normal controls; NS). These imbalances resulted in significantly decreased values (P<0.0005) of the ratio of the T4/T8 phenotypes (1.19±0.59 vs 1.86±0.29 of the controls). Untreated patients (13 of 24) exhibited significantly decreased proportions of T3-positive (P<0.003) and T4-positive (P<0.001) cells and increased proportions of T8-positive cells (P<0.007). Absolute numbers of T4-positive cells were significantly decreased (P<0.007), and those of T3-positive cells were moderately decreased (P<0.04). In contrast, absolute numbers of WBC, lymphocytes, and T8-positive cells were within the normal range. Treated patients (11 of 24) exhibited significantly decreased proportions of T3-positive (P<0.0005) and T4-positive (P<0.0005) cells and normal proportions of T8-positive cells. Decreased absolute numbers of peripheral blood lymphocytes (P<0.002), T3-positive cells (P<0.0005), and T4-positive cells (P<0.0005) were found in these patients. The absolute numbers of T8-positive cells were within the normal range. These results demonstrate significant T-cell imbalances in patients with multiple myeloma. The significance of these findings is discussed.