Neutrophil surface molecules function in part as biological sensors. Surface antigens undergo several changes during neutrophilic maturation to accommodate the cell's function. Surface antigens may appear with neutrophilic maturation, such as CD16b, CD35, and CD10; disappear with maturation, such as CD49d and CD64; be maintained during maturation, such as CD32, CD59, and CD82; or disappear with...

The effect on granulopoiesis of 6-mercaptopurine alone, and in combination with allopurinol, was studied in mice using an in vitro colony-forming assay for granulocytic progenitor cells. The combination of 6-mercaptopurine and allopurinol pro duced significantly greater suppression of de novo granulo poiesis than did 6-mercaptopurine alone. Allopurinol in very high doses was found to be myelosu...

Hematopoiesis in general is demand driven and adaptive, but in contrast to erythropoiesis or thrombocytopoiesis, our knowledge on how neutrophil production is adapted to individual needs remains incomplete. Recently, neutrophil homeostasis has been shown to depend on danger receptors, macrophages, and even circadian rhythms. Puzzle pieces for a broader view of neutrophil homeostasis accumulate,...

Neutropenic conditions are prevalent in leukemia patients and are often associated with increased susceptibility to infections. In fact, emergency granulopoiesis (EG), a process regulating neutrophil homeostasis in inflammatory conditions and infections, may occur improperly in leukemic conditions, leading to reduced neutrophil counts. Unfortunately, the mechanisms central to dysfunctional EG r...

In a theoretical model describing the factoral hypotheses of granulopoietic control in terms of modern concepts of genetic regulation, the sequential nature of the differentiation process is explained as co-induction of operons or "gene clusters." The full derepression of the operator gene is possible in the presence of both a primary inducing "factor," and a "co-inducer" produced by the last s...

Serum obtained from mice after irradiafter irradiation and in time to the granation shows an enhanced ability to stimulopoietic response of the marrow to the ulate growth of granulocytic colonies in neutropenia. The relationship suggests vitro. This enhanced stimulatory ability that the active factor in postirradiation of serum is related in both time and magserum might be granulopoietin, the p...

Incubation of human macrophages with endotoxin resulted in significantly enhanced colony-stimulating activity (CSA) production by these cells. Preincubation of endotoxin with mature granulocytes abolished this stimulatory effect. The stimulatory effect of endotoxin on macrophage CSA production was not abolished, however, by preincubation with NaF-treated granulocytes, granulocyte membranes, or ...

Background Adenosine deaminase (ADA) deficiency is a disorder where the accumulation of purine metabolites, which are particularly toxic to lymphocytes, can lead to severe, life threatening infections. In addition, ADA deficiency also affects other tissues. Few reports describe the presence of neutropenia in these patients, primarily in older patients after hematopoietic stem cell transplantati...