A T chronic lymphocytic leukemia with large granular lymphocytes. Phenotype and functions of leukemic cells under in vitro treatment by differentiation inducers

Large-cell "mixed-phenotype" lymphoma in AIDS. Identification of a CD5-expressing subset of B-cell non-Hodgkin's lymphoma

We have characterized cells from an AIDS-associated non-Hodgkin's lymphoma (NHL). We found a malignant CD5+ B cell (approximately three-fourths of cells), with the balance of cells comprised of T cells having an activated phenotype. The lymphoma was unusual, in that all cells bear "T-lineage" markers, CD3 and CD5, and "B-lineage" markers, CD19 and CD20. Thus, conventional immunohistologic techniques were insufficient to type this mixture of cells; single-cell analysis was required. These "mixed-phenotype" lymphomas may occur frequently in AIDS-associated NHL. Our results show striking similarity to those obtained in the analysis of certain murine CD5+ B-cell lymphomas, suggesting that the study of lymphomagenesis in the mouse may aid in the understanding of AIDS-associated NHL.

Natural killer (NK) activity of cultured S100 beta-positive T-leukemia cells

In order to clarify the function of human S100 beta-positive T-cells, S100 beta-positive T-leukemia cells (S100 beta TLC) were examined in vitro. S100 beta TLC were obtained from the peripheral blood of a patient with S100 beta-positive T-cell leukemia and enriched by an E-rosetting method. Two dimensional flow cytometric analysis indicated that the vast majority of the E-positive fraction were S100 beta TLC expressing CD3 and CD8 antigens. Although S100 beta TLC expressed CD3 antigen, they were negative for the alpha/beta and gamma/delta T-cell antigen receptor (TCR) defined by monoclonal antibodies (mabs) WT-31 and delta TCS-1, respectively. It was speculated that S100 beta TLC initially expressed alpha/beta TCR but lost it during malignant transformation. When S100 beta TLC were cultured for 24 h, they acquired cytotoxic activity towards various NK-sensitive cell lines including K-562, Molt-3 and CEM-CCLF, but did not exhibit lysing activity towards NK-resistant cell lines including Raji, Daudi and MT-1. Despite the NK-activity of cultured S100 beta TLC, they lacked the morphological features of large granular lymphocytes (LGL). S100 beta TLC did not exhibit lymphokine-activated killer (LAK) activity. When S100 beta TLC were cocultivated with NK-sensitive cells or NK-resistant cells, they selectively bound to NK-sensitive cells, indicating that they lysed target cells by cell-to-cell contact. The finding that S100 beta TLC lacked TCR molecules and their NK activity was not inhibited by mabs reactive with the CD3-TCR complex indicated that the CD3-TCR complex was not involved in their target recognition.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromosomal abnormalities define clonal proliferation in CD3- large granular lymphocyte leukemia

Six patients with lymphoproliferative disorder of large granular lymphocytes (LDGL) were studied for chromosomal abnormalities. When the patients were divided into two groups depending on the expression of a mature antigen of T cell lineage, CD3, two with CD3+ phenotype had a stable disease, whereas three of the four patients with CD3- phenotype had marked hepatosplenomegaly and a highly aggressive disease. Chromosomal abnormalities were detected in four of six patients, indicating a clonal proliferation of large granular lymphocytes in individual patients. In particular, chromosomal abnormalities were found in three of the four patients with CD3- LDGL, all of which had a germ-line configuration of the T cell receptor beta-chain gene. Thus, the chromosomal abnormalities provide definitive evidence for the clonal origin of the expanded cells in the CD3- LDGL.

Lipoperoxidation and T-cell leukemia of childhood. Effects of indomethacin

Serum thiobarbituric acid (TBA) reactivity for lipoperoxidation products was assessed at diagnosis in children with T-cell and common acute lymphocytic leukemia (ALL) and T-lymphoblastic lymphoma. Comparisons were made among these groups and with healthy controls. Mean TBA reactivity (mumol malondialdehyde/L serum) was increased (P less than 0.01) in the T-cell leukemia group versus common ALL and T-lymphoblastic lymphoma patients and controls, respectively. The increase in lipoperoxidation products in T-cell ALL appeared to bear a positive relation to peripheral leukocyte counts, and was accompanied by increased serum prostaglandin E2 (PGE2) levels in most representative cases. Indomethacin added to a childhood T-cell ALL line (SUP-T3), at a concentration known to inhibit prostaglandin synthesis in vitro (i.e., 3 micrograms/mL), effected significant increases in the numbers of natural killer (NK; Leu-11+ and Leu-19+) cells (P less than 0.01) and B-lymphocytes (P less than 0.05), and significant decreases in cell viability (P less than 0.01). Indomethacin may be a useful agent for enhancing the antileukemic immune response in T-cell ALL.