T - Lymphoproliferative Disease and Related Disorders in Humans and Experimental Animals : A Review of the Clinical , Cellular , and Functional Characteristics

T7 lymphocytes are those lymphocytes that express receptors for both the Fc portion of lgG and sheep erythrocytes. A very high proportion of normal T. lymphocytes are large granular lymphocytes (LGL). the cell responsible for most, if not all. natural killer (NK) and antibody-dependent cellmediated cytotoxicity (ADCC) in humans. rats. and mice. In general. these cells are large lymphocytes with prominant azurophilic granules in the cytoplasm. Recently, a group of lymphoproliferative disorders made up predominantly of T. lymphocytes has been described. The most common and best studied of these disorders we refer to as “chronic T. -Iymphoproliferative disease” (T. -LPD). In most cases. this disease represents the abnormal expansion of LGL. which is reflected by an increase in functionally active NK or ADCC effector cells. The chronic T. -LPD lymphocytes are generally characterized as Eand EA-rosette positive. acid-phosphatase. and 9-gIucuronidase positive and express the pan-T antigens 0KT3/Leu-4. OKT1 1 /Leu-5.