ABSTRACT
To what degree T-cell dysfunction contributes to the immune defect in HCL is not completely understood. There is a marked T-cell imbalance with an increased number of suppressor cells with a low helper-to-suppressor ratio [16]. T-cell lymphocytes are abnormally activated [17] and nonresponsive, possibly owing to inadequate antigen presentation due to the absence of circulating monocytes [18]. Delayed hypersensitivity to recall antigens is impaired, and there is no antibody-dependent cellular cytotoxicity [19]. In contrast, the serum immunoglobulin levels are normal in most patients [7,20].
