This study investigated the numbers of large granular lymphocytes (LGL) and their relationship to natural killer (NK) function, as assessed by their capacity to lyse the human tumor target, K562. Peripheral blood mononuclear cells from 42 normal controls and from 171 patients suffering from various nonmalignant or malignant diseases were evaluated. Also studied were samples from a patient under...

BACKGROUND Large granular lymphocyte leukemia is a semi-autonomous clonal proliferation of cytotoxic T cells accompanied by immune cytopenias and various autoimmune conditions. Due to the rarity of this disease and its association with autoimmune diseases, a theoretical germline or somatic mutation might have significant penetrance, thus enabling detection, even from samples of suboptimal size,...

In this report we have used highly purified populations of natural killer (NK) cells: large granular lymphocytes (LGL). This study demonstrates that freshly isolated and interleukin 2-cultured LGL produce the specific neutral serine protease, plasminogen activator (PA). We have found that the enzyme is expressed in both an extracellular form as well as in a cell-associated form. Upon subcellula...

Human cyclic neutropenia occurs in adults as well as children. Clinical illness is similar in the childhood and adult diseases, but distinctly different modes of onset suggest heterogeneity in its pathophysiology. We studied seven patients with cyclic neutropenia, three with disease acquired in adulthood, and four with the childhood-onset disorder. All three patients with adult-onset cyclic neu...

The activation signals leading to proliferation of normal and leukemic CD3+ large granular lymphocytes (LGL) were studied in vitro. Anti-CD3 monoclonal antibody (MoAb) alone (P less than .01) and recombinant interleukin-2 (IL-2) alone (P less than .01) caused significant stimulation of peripheral blood mononuclear cells (PBMC) from four CD3+ LGL leukemia patients, as measured in a 3H-thymidine ...

BACKGROUND Clonal diseases of large granular lymphocytes (LGLs) are rare lymphoproliferative malignancies that arise from either mature T-cell (CD3+) or natural killer (NK)-cell (CD3-) lineages. They manifest a distinct biologic behavior that ranges from indolent to very aggressive. METHODS We discuss four distinct diseases involving LGLs: indolent T-cell LGL leukemia, aggressive T-cell LGL l...

BACKGROUND Large granular lymphocytic leukaemia (LGL-leukaemia) is considered a rare disease. LGL-leukaemia is usually of the T-cell type, but a minority displays an NK-cell phenotype. Incidence and prevalence are unknown. MATERIAL AND METHODS We identified patients with LGL-leukaemia (with well-defined diagnostic criteria) diagnosed at Rikshospitalet University Hospital between 01.10.2001 an...