The effect of granulocyte colony-stimulating factor (G-CSF) on the activity of granulocyte enzymes in children with cancer who developed neutropenia after chemotherapy.

PURPOSE: G-CSF is a cytokine that stimulates the proliferation and maturation of granulocyte precursor cells. The results of in vitro and in vivo investigations conducted on animal models revealed that this cytokine influences the functions of mature granulocytes increasing the activities of the granulocyte enzymes participating in phagocytosis. MATERIAL AND METHODS: The investigation was conducted on a group of 26 children (age: 1.5-17 years) with cancer who developed neutropenia after chemotherapy and were treated with G-CSF. The control group included 29 healthy children (age: 5-17 years). The heparinized blood samples were taken before the injection of the stimulator (time 0) and after the 2nd and 5th injection of G-CSF (on day 3 and 6). Activities of granulocyte enzymes involved in the process of phagocytosis (myeloperoxidase, acid and alkaline phosphatase and esterase) in blood smears were evaluated. RESULTS: It has been found that G-CSF affects the activity of granulocyte enzymes by the normalization of decreased values of myeloperoxidase, acid phosphate and increasing the normal values of alkaline phosphate activity. The enzyme activities increased during the following days of treatment. CONCLUSION: Based on the obtained results, we can conclude that G-CSF activates the formation of fully competent granulocytes in cytostatic-treated children with various neoplastic diseases.

The effect of granulocyte colony stimulating factor on neutrophil functions in children with neutropenia after chemotherapy in the course of neoplasma.

PURPOSE: Granulocyte-colony stimulating factor stimulates proliferation and maturation of granulocyte precursor cells. The influence of this hematopoietic factor on phagocytic function of granulocytes was performed in in vitro experiments. The aim was to find, whether G-CSF applicated to children with neutropenia after chemotherapy influences phagocytic functions of neutrophils and whether evaluated parameters depend on a time of G-CSF injection? MATERIAL AND METHODS: The investigation was conducted on a group of 26 children with cancer, treated with granulocyte-colony stimulating factor in the cause of neutropenia after chemotherapy. The control group included 29 healthy children. The blood was taken before the stimulator injection and after 2 and 5 granulocyte-colony stimulating factor injections. The percentage of phagocyting cells and the phagocytic index of granulocytes were determined in heparinized whole blood samples. Oxygen metabolism was evaluated in the absence and presence endotoxin by nitroblue tetrazolium reduction. RESULTS: It was found that granulocyte-colony stimulating factor activates phagocytic functions of neutrophils by normalizing low values of phagocytic index and number of granulocytes, reducing dye nitroblue tetrazolium reduction and increasing the number of phagocytic cells. CONCLUSION: Based on obtained results we can conclude that granulocyte-colony stimulating factor apart from granulopoiesis stimulation can also increase phagocytic and oxidative capacity of granulocytes after chemotherapy.

[Phagocytosis and oxidative metabolism of granulocytes in mice after stem cell factor (SCF) injection]. / Fagocytoza i metabolizm tlenowy granulocytów myszy poddanych dzialaniu czynnika wzrostowego komórek pnia (SCF).

Stem Cell Factor (SCF) can stimulate the growth and development of primitive multipotential and unipotential hematopoietic stem cells, either alone or in combination with other cytokines such as Granulocyte-Macrophage Colony Stimulating factor (GM-CSF) and Granulocyte-CSF (G-CSF). It was found that these cytokines can also stimulate the function of granulocytes but there is no information concerning SCF influence on the function of these mature cells. SCF was injected into mice subcutaneously during 5 consecutive days in a dose of 1 microgram/kg/d. An examination of the percentage of phagocytic granulocytes and NBT test was performed. The activity of acid phosphatase (AcP), alkaline phosphatase (AP), peroxidase (MPO) and esterase were determined by cytochemistry methods. On the basis of obtained results we can conclude that SCF evidently increases all tested parameters connected with the metabolism of phagocytosis.

[Phagocytosis and killing of Staphylococcus aureus by mouse granulocytes after interleukin-3 (IL-3) injection]. / Fagocytoza i zabijanie komórek Staphylococcus aureus przez granulocyty myszy poddanych dzialaniu interleukiny-3 (IL-3).

Interleukin-3 is a multipotential hematopoietic growth factor, which like other colony stimulating factors (CSFs) is effective "in vitro" stimulation of the mature cells function. It was found that IL-3 synergistically with GM-CSF and G-CSF stimulated the proliferation of the granulocytes. Therefore the purpose of this investigation was the evaluation "in vivo" of the influence of IL-3 on the phagocytosis, bactericidal activity, and enzyme activities of granulocytes. IL-3 was injected into mice subcutaneously during 5 days in dose 1 microgram/kg/d. The examination of the percent of cells phagocytizing bacteria (Staphylococcus aureus), NBT test and bactericidal activity, were performed every day and evident increase of the tested parameters was found. Additionally the enzyme activities in primary granules were measured and showed on increase of acid phosphatase and peroxidase activity.