Abnormal lymphocyte function in childhood leukemia

Abstract

(1 0 f 3% lymphocytes, 88 f 4% lymphoblasts and 18 k 28% T cells) had a significantly lower response to PHA on these days (13,609 * 5,568 cpm).Six of the ten high-WBC patients had a delayed peak response on the sixth or seventh day of culture. This abnormal response to PHA is similar to that which has been described in patients with chronic lymphatic leukemia and is at least partially due to the dilution of a normal lymphocyte population by the proliferation of a population of non-PHA-responsive lymphoblasts.The remaining four high-WBC patients had flat PHA dose-and time-response curves and a poorer clinical course. Two of them had T-cell leukemia. The absence of response to PHA in these children may characterize a group of patients with acute lymphoblastic leukemia who are immunodeficient at the time of diagnosis and may reflect the presence of a unique population of lymphoblasts with suppressor activity.Sixteen patients with a WBC < 20,000/ cu mm (5 1 f 5% lymphocytes, 28 f 7%

Some Aspects of the Lymphocytes Kinetics during Treatment of Childhood Acute Lymphoblastic Leukemia

“…It is of interest that all of the patients mentioned died after 1 6 months, without obtaining remission. These pa tients seem to be analogous to those described by Zusnum and Nesbit [18], i.e. to those with flat PHA dose and time response curve and simultaneous short survival period, which was suggested to correspond to their truly immunological abnormality.…”

“…So it seems doubtful that the observed high amount of Ml cells was due to the proliferation of self-proliferating leukemic cells. Previous studies in dicate that the peripheral lymphocyte response to PHA in children with ALL and high initial WBC docs not reach its normal value until 96 h of culturing [18]. The nature of the delay remained obscure, although it was suggested that it may be due to the dilution of a normal lymphocyte population by the circulating non-PHA-responsive lymphoblasts [10,18].…”

“…Previous studies in dicate that the peripheral lymphocyte response to PHA in children with ALL and high initial WBC docs not reach its normal value until 96 h of culturing [18]. The nature of the delay remained obscure, although it was suggested that it may be due to the dilution of a normal lymphocyte population by the circulating non-PHA-responsive lymphoblasts [10,18]. Our stu dies suggested that the described phenomenon of de lay could not only depend upon the low number of responding cells but also upon the late beginning of the lymphocytes proliferation.…”