Serum selenium levels in untreated children with acute lymphoblastic leukemia. I.

Serum selenium in the control group of 79 children aging 1 to 16 years was measured. A slight increase in serum selenium values with age occurred. The 89 patients of the test group were suffering from malignant proliferative diseases.

Defect of NK activity in children with untreated acute lymphocytic leukemia (ALL). I. Dependence on the blast count and phenotype, and response to exogenous and endogenous alpha-interferon.

Endogenous NK-activity (eNK) against K-562 cells was determined in peripheral blood of 68 children with acute lymphocytic leukemia (ALL) before treatment. In 53% of them it was depressed, and in 47% it was within the range of control children (27) and adults (104). There was a significant negative correlation between blast contamination of peripheral blood and the level of eNK-activity.

Expression of haematopoietic progenitor cell-associated antigen BI-3C5/CD34 in leukemia.

The expression of progenitor cell-associated antigen CD34, defined with monoclonal antibody BI-3C5, was investigated in cells from 109 patients with leukaemia. No reactivity was found in chronic leukaemias, whereas 31% of acute myelogenous leukaemia (AML) and most non-T, non-B acute lymphoblastic leukaemia (ALL) expressed CD34. Examples of BI-3C5+ AML included M1 and M2 FAB types only; all but one were myeloperoxidase positive.

Premature chromosome condensation in children with acute lymphocytic leukemia (L1) and malignant histiocytosis.

In this study we report the observation of premature chromosome condensation (PCC) in two children with acute lymphocytic leukemia L1 and one child with malignant histiocytosis. Cytogenetic analysis was performed on peripheral blood or bone marrow cells cultivated for 24 hours without mitogen. In all three reported cases the modal karyotype was normal, while 12.