Effect of granulocyte colony stimulating factor on neutropenia induced by cytotoxic chemotherapy

Neutrophil kinetics shortly after initial administration of recombinant human granulocyte colony-stimulating factor: neutrophil alkaline phosphatase activity as an endogenous marker

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) was administered (1.5 micrograms/kg body weight) subcutaneously once daily for 5 to 9 days to 5 patients with malignant lymphoma. In all patients, initial administration of rhG-CSF induced a rapid fall in the neutrophil count within 30 minutes, followed by a recovery and an increase in the neutrophil count within 150 min. A rapid fall in the neutrophil count was accompanied by increased expression of neutrophil C3bi-receptors, and neutrophils left in the circulation had lower activity of neutrophil alkaline phosphatase (NAP) and phagocytosis. A decrease in the NAP scores observed at 30 min reflected a preferential decrease of neutrophils with high NAP activity. A recovery and an increase in the neutrophil count were accompanied by a further decrease of NAP scores, which was caused by a preferential increase of neutrophils with lower NAP activity. The NAP scores of mature neutrophils from peripheral blood were not affected by in vitro treatment of cells with rhG-CSF for up to 150 min at 37 degrees C. These findings and the previous observations that neutrophils in the circulating and marginal pools have high NAP activity and neutrophils in the bone marrow pool have low NAP activity taken together suggest that, following initial administration of rhG-CSF, functionally active neutrophils leave the bloodstream preferentially, which is primarily followed by an influx of neutrophils from the bone marrow, but not by demargination of sequestered neutrophils.

Treatment of chemotherapy-induced neutropenia in children with subcutaneously administered recombinant human granulocyte colony-stimulating factor

Fifty-six children with various malignancies were treated subcutaneously with recombinant human granulocyte colony-stimulating factor (rhG-CSF, KRN 8601) for neutropenia induced by cancer chemotherapy. Patients received the first chemotherapy without rhG-CSF (control course). In the second course, rhG-CSF was given once daily, starting 3 days after completion of identical chemotherapy (day 3) and continuing until day 12. At day 12, the white blood counts and neutrophil counts were found to be 6.8 and 30 times higher in the rhG-CSF course than in the control course (P = .0001) Nadirs of white blood counts and neutrophils were significantly elevated in the rhG-CSF course (P = .003 and .0001, respectively). rhG-CSF administration shortened the neutropenic period in the majority of patients. Children tolerated the rhG-CSF administration well and we have hereby confirmed that rhG-CSF administration is useful for proceeding with chemotherapy in children with cancer.

Comparative effects of a recombinant and a mutein type of granulocyte colony stimulating factor on the growth of Meth-A fibrosarcoma with 5-fluorouracil chemotherapy

The present study was designed to evaluate the effects of a recombinant human G-CSF (rhG-CSF) and a mutein G-CSF (KW-2228) on leucopenia and tumor growth in mice treated with 5-fluorouracil (5-FU). In normal mice, the number of leucocytes (white blood cell, WBC) reached the peak 12 hours after a single injection of either type of G-CSF and decreased to the normal level after 24 hours. Daily administration induced a continuous increase in the WBC count, however, administrations at intervals did not. Meth-A fibrosarcoma was subcutaneously inoculated into the backs of syngeneic BALB/c mice. The mice were treated with 5-FU alone or with G-CSFs. Chemotherapy with 5-FU alone resulted in leucopenia and an insignificant inhibition of tumor growth. The conjunctive administration of G-CSFs with 5-FU resulted in a significantly augmented inhibition of tumour growth, and leukopenia was not seen. This augmenting effect was more prominent with KW-2228. These results suggest that in 5-FU chemotherapy G-CSFs may be beneficial in restoring the number of leucocytes from leucopenic state and in augmenting the tumor inhibitory effect. Furthermore, KW-2228 may be more beneficial than the natural type rhG-CSF.

Topics in clinical pharmacology: filgrastim, a myeloid colony stimulating factor

Filgrastim (granulocyte colony stimulating factor) recently became commercially available for the treatment of chemotherapy-induced neutropenia. Studies have shown that filgrastim induces a dose-dependent granulocytosis in humans, thereby shortening the period of neutropenia in patients treated conventionally with submarrow ablative doses of chemotherapy, as well as with marrow ablative therapy given in the bone marrow transplant setting. By reducing the incidence and severity of infections and mucositis in patients treated with chemotherapy, it has a significant economic impact since it shortens the duration of antibiotic administration and hospitalization. Adverse reactions reported are limited to mild to moderate bone pain. Several other potential applications are being investigated for filgrastim, including treatment of patients with myelodysplastic syndrome and congenital neutropenia.

Granulocyte colony stimulating factor in the management of chronic neutropenia

OBJECTIVE

To report two cases of chronic neutropenic states successfully treated with granulocyte colony stimulating factor (G-CSF).

CLINICAL FEATURES

A 23-year-old man with severe congenital cyclic neutropenia causing lifelong recurrent infections and consequent debilitation presented with intractable infected leg ulcers. A 56-year-old man with acquired idiopathic neutropenia presented with severe perianal infection and sepsis.

INTERVENTION AND OUTCOME

Both patients were successfully treated with recombinant G-CSF.

CONCLUSION

G-CSF is an agent with major clinical potential for the therapy of primary neutropenic states.

Detection and quantitation of recombinant granulocyte colony-stimulating factor charge isoforms: comparative analysis by cationic-exchange chromatography, isoelectric focusing gel electrophoresis, and peptide mapping

Routine quantitation of recombinant human granulocyte colony-stimulating factor charge isoforms in the purified protein product requires development of a reliable analytical method. In this report, isoelectric focusing gel electrophoresis, peptide mapping, and cation-exchange high-performance liquid chromatography are compared and evaluated in the analysis of charge isomers that may be present in the recombinant factor. Due to a lack of sensitivity and reliability, isoelectric focusing gel electrophoresis and peptide mapping are not recommended. However, peptide mapping can distinguish aberrant peptides with differences in charges and provide separation for subsequent structural characterization. By this approach, an N-terminally blocked formylmethionyl species was identified to be the minor charge isoform in the purified preparations of recombinant human granulocyte colony-stimulating factor. In contrast to electrophoresis and peptide mapping, a strong cationic-exchange chromatographic procedure was found to be the most selective, sensitive, and reproducible analytical method. The sensitivity and reliability of the method were evaluated and validated using the formylmethionyl isoform and several deamidated analogs (Gln----Glu) made by site-directed mutagenesis. Recombinant human granulocyte colony-stimulating factor preparations contain a very low to undetectable level of the formylmethionine isoform and have no detectable deamidated isoforms.

Fatal haemoptysis associated with invasive pulmonary aspergillosis treated with high-dose amphotericin B and granulocyte-macrophage colony-stimulating factor (GM-CSF)

Opportunistic pulmonary infections are a leading cause of morbidity and mortality in patients with chemotherapeutically treated neoplasias. With increasingly aggressive cytotoxic regimens causing prolonged neutropenia, the risk of systemic mycoses and in particular of invasive pulmonary aspergillosis has increased. We review the case of a 10-year-old child suffering from relapsed lymphoblastic leukaemia and from high-dose amphotericin B-treated invasive pulmonary aspergillosis acquired during long-standing neutropenia in the initial phase of remission induction chemotherapy. The patient died in remission after GM-CSF-induced bone marrow recovery and clinical and radiological improvement with stable plasmatic coagulation and normal thrombocyte count. Peracute massive pulmonary bleeding caused by the simultaneous arrosion of a greater pulmonary artery and a lobar bronchus by a liquefactive fungal focus was responsible. In patients with chemotherapeutically induced neutropenia and invasive aspergillosis, bone marrow recovery may lead to the liquefaction of pulmonary foci, and, in view of the well-known vasotropic nature of the infection, to a potentially lethal arrosion bleeding. With the emerging use of colony-stimulating factors for shortening and overcoming neutropenia, this so far rare complication may become of increasing importance.

Development of immunotherapeutic strategies for the treatment of malignant neoplasms

Focused preclinical studies have been used to gain insight into the mechanism of therapeutic activity of cytokines, growth factors and biological response modifiers (BRMs). These data can then be used to develop a clinical hypothesis to facilitate the development of these new biological drugs. In this manuscript, we discuss a number of preclinical and clinical studies using interferon-gamma, IL-2, and the colony stimulating factors. The importance of the systematic profiling of the biological activity of such biological drugs is emphasized and we discuss the utility of the mechanistic data in their clinical development. The overall preclinical approach identifies the cellular, biochemical or gene regulatory event that is associated with the therapeutic activity of a biologic and this surrogate (be it biological, chemical, or quality of life) is then used to optimize the clinical protocol in a phase 1b trial. This, in theory, results in the rapid identification of the optimal dose, schedule and route of administration for subsequent testing in a phase II/III clinical trial.

Marrow proliferation and the appearance of giant neutrophils in response to recombinant human granulocyte colony stimulating factor (rhG-CSF)

During a study of recombinant human granulocyte colony stimulating factor (rhG-CSF) administration, 15 patients received twice daily i.v. infusions and nine patients received daily s.c. infusions of rhG-CSF for 5 d prior to cytotoxic therapy, and then a second course subsequent to melphalan administration. There was a striking dose-related neutrophilia and the appearance in the blood of early myeloid cells that express the intercellular adhesion molecule CD54. In addition, giant neutrophils or macropolycytes were observed in the peripheral blood of all patients. These cells were evident on the display of the Technicon H*1 as a population of large peroxidase positive cells, and using Feulgen staining these cells were shown to be tetraploid. Bone marrow kinetics studies performed on Day 4 or 5 indicated an increase in the proportion of bone marrow cells in S phase, G2 and mitosis, reflecting a proliferative response of the marrow. Large myeloid precursors and occasional binucleate promyelocytes were seen in the bone marrows done on Days 14 and 18 but not on Day 5. These findings indicate that administered G-CSF has both quantitative and qualitative effects on myeloid cells in vivo.

Recombinant human granulocyte-colony-stimulating factor in the treatment of patients with chronic benign granulocytopenia and congenital agranulocytosis (Kostmann's syndrome)

Seven patients with chronic benign granulocytopenia and nine patients with congenital agranulocytosis, received consecutive seven-day courses of recombinant human granulocyte-colony stimulating factor at a starting dose of 50 micrograms/m2/day, subcutaneously. If there was no response the doses were increased to 300 micrograms/m2. All patients with chronic benign granulocytopenia responded rapidly at the minimum dose within 1-3 days after administration. By contrast, only three of the nine patients with congenital agranulocytosis responded within 1-7 days at this dose. Four patients with congenital agranulocytosis showed a response between days 7-19 at a dose of granulocyte-colony-stimulating factor 100-200 micrograms/m2 but in the remaining two cases no response was obtained. The administration of granulocyte-colony-stimulating factor was shown to be safe and effective also in reducing infectious episodes in these patients. Previously it was reported that granulocyte-colony-stimulating factor 10-30 micrograms/kg/day was effective for patients with congenital agranulocytosis. These results indicate that patients with congenital agranulocytosis may require much higher doses of recombinant human granulocyte-colony-stimulating factor than patients with chronic benign granulocytopenia and that the response to ordinary doses of recombinant human granulocyte-colony-stimulating factor may be useful in differentiating between chronic benign granulocytopenia and congenital agranulocytosis.

The use of granulocyte colony-stimulating factor to shorten the interval between cycles of mitomycin C, vindesine, and cisplatin chemotherapy in non-small-cell lung cancer

We investigated the possibility of shortening the interval between courses of the commonly prescribed 28-day MVP (mitomycin C, vindesine, and cisplatin) regimen in patients with non-small-cell lung cancer (NSCLC). We conducted a nonrandomized phase II study using recombinant human granulocyte colony-stimulating factor (G-CSF, Chugai) to explore the possibility of shortening the cycle length to 21 days and compared the results with those obtained in historical controls who had received the standard 28-day regimen. A total of 40 patients, 37 of whom were evaluable, were entered in the 21-day treatment group of the trial and were compared with 38 historical controls who had received standard 28-day cycles of MVP at our institution. Patients in the 21-day group received mitomycin C at 8 mg/m2 on day 1, vindesine at 3 mg/m2 on days 1 and 8, and cisplatin at 80 mg/m2 on day 1, with the schedule being repeated every 21 days. Controls had received the same regimen, albeit at 28-day intervals. G-CSF was given s.c. to the patients in the 21-day group at a daily dose of 2 micrograms/kg from day 2 to day 21 of every MVP cycle. The administration of G-CSF to these patients accelerated neutrophil recovery as compared with that observed in the historical controls. Significant differences were found between the two groups in terms of mean neutrophil nadirs (2666/microliters in the first cycle and 1369/microliters in the second for the G-CSF group vs 416/microliters in the first cycle and 685/microliters in the second cycle for the control group; P < 0.0001) and the mean duration of neutropenia (< or = 1000/microliters; 1.0 day in the first cycle and 1.7 days in the second for the G-CSF group vs 8.0 days in the first cycle and 6.9 days in the second for the control group; P < 0.0001). This enabled 32 (86%) of 37 patients in the G-CSF group to complete > or = 2 cycles on schedule. In 10 patients, the bone marrow aspirates taken after G-CSF administration showed increases in band neutrophil and myelocyte percentages. In conclusion, MVP treatment of patients with NSCLC at 21-day intervals is possible with the support of G-CSF.

Infection risk in patients with small cell lung cancer receiving intensive chemotherapy and recombinant human granulocyte-macrophage colony-stimulating factor

The effect of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) was assessed in 17 patients with small cell lung cancer. GM-CSF was initially given alone by subcutaneous injection for 10 days at 50-500 micrograms/m2 per day. There was a significant rise in neutrophils and eosinophils and to a lesser extent in monocytes at all dose levels. During the next phase, patients received chemotherapy (etoposide, ifosfamide and doxorubicin), and GM-CSF was given on alternate cycles, the patients acting as their own controls, so that the amelioration of chemotherapy could be assessed. Despite partial abrogation of the neutropenia associated with chemotherapy (P = 0.04), GM-CSF failed to reduce the frequency of febrile episodes in association with neutropenia, with six episodes occurring on GM-CSF and seven while patients were not receiving GM-CSF after a total of 66 cycles of chemotherapy. After GM-CSF, there was a reduction in polymorph phagocytic ability and chemotaxis in 6/12 and 9/11 patients, respectively. Timed blood counts after GM-CSF administration showed that peak leucocytosis occurred at 8-12 h and fell to two-thirds of this level at 24 h. Toxicity consisting of lethargy, myalgia and bone pain occurred at all dose levels but was manageable. 2 patients had thromboembolism. This study failed to demonstrate a reduction in the infection risk associated with moderately intensive chemotherapy for small cell lung cancer despite the partial abrogation of neutropenia.

Effect of recombinant human granulocyte colony-stimulating factor on survival in lethally irradiated mice

Repeated injections of recombinant human granulocyte colony-stimulating factor (rhG-CSF) to lethally irradiated mice increased the rate of animal survival. Dose modification factor was 1.20 when 4.5 micrograms/mouse of rhG-CSF was given daily for 14 days after whole body irradiation. Haematological examinations revealed that rhG-CSF increased the number of blood-circulating leukocytes, neutrophils, monocytes and erythrocytes, but not that of lymphocytes and thrombocytes. Spleen weight and number of endogenous spleen colonies were also increased by rhG-CSF treatment compared with the values for mice irradiated only.

Postirradiation treatment with granulocyte colony-stimulating factor and preirradiation WR-2721 administration synergize to enhance hemopoietic reconstitution and increase survival

These studies tested whether WR-2721 could be used to protect hemopoietic stem cells, which after irradiation could be stimulated by granulocyte colony-stimulating factor (G-CSF) to proliferate and reconstitute the hemopoietic system. Female C3H/HeN mice were administered WR-2721 (4 mg/mouse, i.p.) 30 min before 60Co irradiation and G-CSF (2.5 micrograms/mouse/day, s.c.) from days 1-16 after irradiation. In survival studies, saline, G-CSF, WR-2721, and WR-2721 + G-CSF treatments resulted in LD50/30 values of 7.85 Gy, 8.30 Gy, 11.30 Gy, and 12.85 Gy, respectively. At these LD50/30 values, the dose reduction factor (DRF) of 1.64 obtained in combination-treated mice was more than additive between the DRF's of G-CSF-treated mice (1.06) and WR-2721-treated mice (1.44). Bone marrow and splenic multipotent hemopoietic stem cell (CFU-s) and granulocyte-macrophage progenitor cell (GM-CFC) recoveries were also accelerated most in mice treated with WR-2721 + G-CSF. In addition, mice treated with WR-2721 + G-CSF exhibited the most accelerated peripheral blood white cell, platelet, and red cell recoveries. These studies (a) demonstrate that therapeutically administered G-CSF accelerates hemopoietic reconstitution from WR-2721-protected stem and progenitor cells, increasing the survival-enhancing effects of WR-2721 and (b) suggest that classic radioprotectants and recombinant hemopoietic growth factors can be used in combination to reduce risks associated with myelosuppression induced by radiation or radiomimetic drugs.

Immunobiology of hematopoietic colony-stimulating factors: potential application to disease prevention in the bovine

Colony-stimulating factors are a family of glycoproteins instrumental in regulation of hematopoiesis and inflammation. Clinical effects of various colony-stimulating factors have been reported in murine and human hosts. This review summarizes findings from some clinical trial evaluations of macrophage colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, granulocyte colony-stimulating factor, interleukin-1, interleukin-3, interleukin-4, interleukin-5, interleukin-6, and interleukin-7 administration to other species. These factors stimulate clonal expansion of progenitor cells in the bone marrow, induce differentiation of various cell lineages to a mature phenotype, and, in some cases, enhance the effector activities of immune cells. Each colony-stimulating factor has distinct lineages of bone marrow cells upon which they act, although there is some overlap in lineage activity and synergy between colony-stimulating factors. The close relationship in biological activity among different colony-stimulating factors is also reflected at the genomic level at which genes for some hematopoietic growth factors have been mapped to a region of human chromosome 5. Recently, colony-stimulating factor administration to cattle and its potential application to disease control in bovine preventive medicine programs has been investigated. Data from recent hematological, immunological, and intramammary bacterial (Staphylococcus aureus and Klebsiella pneumoniae) challenge studies in dairy cows are reviewed. These studies, with limited numbers of cows, found that rate of new infections, as well as duration and severity of infection, were reduced by pretreatment of cows with granulocyte-colony stimulating factor. The dose-dependent hematological and immunomodulatory effects of granulocyte colony-stimulating factor administration may explain reduced severity and incidence of mastitis in dairy cows given granulocyte colony-stimulating factor.

Granulocyte colony-stimulating factor (G-CSF) treatment in a neutropenic leukemia patient with diffuse interstitial pulmonary infiltrates

Adult respiratory distress syndrome (ARDS) in patients suffering from acute leukemia usually occurs during chemotherapy-induced neutropenia. In addition, intensified chemotherapy with high-dose cytosine arabinoside and mediastinal irradiation may contribute to the development of ARDS. This complication is usually refractory to conservative treatment with antibiotics, steroids, and mechanical ventilation. In this report, we describe a 25-year-old patient with acute lymphoblastic leukemia who developed ARDS during the phase of chemotherapy-induced neutropenia. Subcutaneous administration of granulocyte colony-stimulating factor (G-CSF) at doses of 300-600 micrograms/day led to a prompt increase of peripheral granulocyte counts. With resolution of neutropenia, respiratory function gradually improved, and mechanical ventilatory support was stopped after 2 weeks. From this observation we surmise that the application of G-CSF may be an effective therapeutic approach for preventing the fatal outcome of ARDS in leukemia patients with bone marrow aplasia.

Granulocyte and granulocyte-macrophage colony-stimulating factors for treatment of neutropenia in glycogen storage disease type Ib

Two children with glycogen storage disease type Ib associated with numerous recurrent bacterial infections as a result of neutropenia and neutrophil dysfunction were treated with recombinant human granulocyte colony-stimulating factor (G-CSF). One of the two patients was previously treated with recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF); therapy had to be discontinued because of severe local side effects. Both colony-stimulating factors at dosages of 3 and 8 micrograms/kg/per day, respectively, increased the average neutrophil counts from less than 300 cells/microliters to more than 1200 cells/microliters. Two subpopulations of neutrophils could be identified by their capacity to produce H2O2: one subpopulation generated H2O2 normally and a second was defective in H2O2 production. The doses of G-CSF effectively enhanced and maintained that subpopulation of neutrophils which produced normal amounts of H2O2. Moreover, these colony-stimulating factor-induced neutrophils demonstrated effective phagocytosis of zymosan particles and killing of staphylococci. Chemotaxis was decreased and could not be normalized by treatment with G-CSF. We conclude that maintenance treatment with G-CSF improved the quality of life in both patients: The number and severity of bacterial infections decreased markedly during treatment. Long-term treatment with G-CSF (12 and 10 months, respectively) was well tolerated, and no adverse clinical events were observed.

Biological Agents in Infectious Diseases

This article examines the use of classical as well as novel immunological agents to augment the immune system. Strategies to prevent infectious disease using vaccines to prime the immune system are discussed. A prospective overview of acquired immunodeficiency syndrome (AIDS) vaccine development provides insights into the possible agents that may be developed in the near future. The rationale for the use of intravenous immunoglobulin and colony stimulating factors in selected clinical situations is also discussed.

Recombinant human granulocyte colony-stimulating factor inhibits the metastasis of hematogenous and non-hematogenous tumors in mice

We studied the effects of in vivo administrations of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on the metastasis of murine hematogenous and non-hematogenous tumors in spontaneous and experimental metastasis models. Spontaneous lung metastasis caused by intra-footpad injections of B16-BL6 melanoma and Lewis-lung-carcinoma (3LL) cells were inhibited by intravenous (i.v.) and subcutaneous (s.c.) injections of rhG-CSF after excision of the primary tumors. Recombinant hG-CSF significantly inhibited liver metastasis when administered i.v. after i.v. injection of L5178Y-ML25 T-lymphoma cells. Multiple i.v. administration of rhG-CSF after the tumor inoculation prolonged the survival times of mice inoculated i.v. with L5178Y-ML25 lymphoma cells. Recombinant hG-CSF did not directly affect the growth of B16-BL6 and L5178Y-ML25 cells in vitro. During the administration periods, both i.v. and s.c. injections of rhG-CSF increased the number of total white blood cells (WBC) in peripheral blood to approximately 3 times the normal level in normal and tumor-bearing mice. We also found that the administration of rhG-CSF stimulates neutrophils to become cytostatic against these tumor cells. Our results indicate that the injection of rhG-CSF is effective in inhibiting lung and liver metastases by activating neutrophils and increasing cell number.

Reduction by granulocyte colony-stimulating factor of fever and neutropenia induced by chemotherapy in patients with small-cell lung cancer

BACKGROUND

Neutropenia and infection are major dose-limiting side effects of chemotherapy. Previous studies have suggested that recombinant methionyl granulocyte colony-stimulating factor (G-CSF) can reduce chemotherapy-related neutropenia in patients with cancer. We conducted a randomized clinical trial to test this hypothesis and the clinical implications.

METHODS

Patients with small-cell lung cancer were enrolled in a multicenter, randomized, double-blind, placebo-controlled trial of recombinant methionyl G-CSF to study the incidence of infection as manifested by fever with neutropenia (absolute neutrophil count, less than 1.0 x 10(9) per liter, with a temperature greater than or equal to 38.2 degrees C) resulting from up to six cycles of chemotherapy with cyclophosphamide, doxorubicin, and etoposide. The patients were randomly assigned to receive either placebo or G-CSF, with treatment beginning on day 4 and continuing through day 17 of a 21-day cycle.

RESULTS

The safety of the study treatment could be evaluated in 207 of the 211 patients assigned to either drug, and its efficacy in 199. At least one episode of fever with neutropenia occurred in 77 percent of the placebo group, as compared with 40 percent of the G-CSF group (P less than 0.001). Over all cycles of chemotherapy, the median duration of grade IV neutropenia (absolute neutrophil count, less than 0.5 x 10(9) per liter) was six days with placebo as compared with one day with G-CSF. During cycles of blinded treatment, the number of days of treatment with intravenous antibiotics, the number of days of hospitalization, and the incidence of confirmed infections were reduced by approximately 50 percent when G-CSF was given, as compared with placebo. Mild-to-moderate medullary bone pain occurred in 20 percent of the patients receiving G-CSF.

CONCLUSIONS

The use of G-CSF as an adjunct to chemotherapy in patients with small-cell cancer of the lung was well tolerated and led to reductions in the incidence of fever with neutropenia and culture-confirmed infections; in the incidence, duration, and severity of grade IV neutropenia; and in the total number of days of treatment with intravenous antibiotics and days of hospitalization.

Direct proliferative actions of stem cell factor on murine bone marrow cells in vitro: effects of combination with colony-stimulating factors

Stem cell factor (SCF), the ligand for the c-kit protooncogene product, was able to stimulate blast cell and granulocytic colony formation by precursors from normal murine bone marrow. The blast cell colonies contained a high content of progenitor cells able to form macrophage and/or granulocyte colonies. Clone transfer studies, the secondary culture of colony cells, and the culture of populations freed of accessory cells all indicated a direct proliferative action of SCF. SCF receptors were present in high numbers on blast cells and in lower numbers on immature granulocytic, monocytic, and eosinophilic cells. Combination of SCF with granulocyte, granulocyte-macrophage, or multipotential colony-stimulating factors, but not macrophage colony-stimulating factor, resulted in enhancement of colony size. Granulocyte colony-stimulating factor enhanced cell proliferation initiated by SCF, but not vice-versa, and resulted in a 10-fold increase in colony cell numbers and a 7-fold increase in progenitor cells in blast colonies. No evidence was obtained that SCF, alone or in combination with granulocyte colony-stimulating factor, could stimulate self-generation by blast colony-forming cells.

The role of cytokines in oncology

The availability of sufficient quantities of recombinant human cytokines and promising preclinical data have led to their introduction into clinical trials. Cytokines have potential as new therapeutic agents in a variety of hematological disorders as well as in solid tumors. Only a few of the still increasing number of these glycoprotein hormones have been studied in humans so far, either as single agents or in combination with chemotherapy and other cytokines. Their clinical effects, beneficial role in supportive care, and use in the treatment of certain cancer patients are reviewed.

Effects of recombinant human granulocyte colony-stimulating factor on leucopenia in zidovudine-treated patients with AIDS and AIDS related complex, a phase I/II study

Twelve male patients, eight with the acquired immunodeficiency syndrome (AIDS) and four with AIDS related complex (ARC), who had zidovudine associated neutropenia (less than 1 x 10(9) neutrophils/l) were treated with recombinant human granulocyte colony-stimulating factor (G-CSF) in a phase I/II study. Treatment consisted of daily subcutaneous injections with G-CSF in a weekly increasing dose of 0.4, 2, 5 or 10 micrograms/kg body weight until a neutrophil count of more than 3 x 10(9) neutrophils/l was observed. This effective dose was continued for up to 4 weeks, followed by 4 weeks observation period without G-CSF treatment. Two patients (both with ARC) reached target neutrophil counts at the lowest G-CSF dose, whereas nine patients needed 2 micrograms/kg. One patient discontinued treatment before he reached target neutrophil counts. Mean (+/- SD) neutrophil counts before and after 1 and 4 weeks of effective dose treatment were 0.65(+/- 0.188) x 10(9), 6.016(+/- 2.595) x 10(9) and 5.54(+/- 4.237) x 10(9)/l respectively (P less than 0.01). The number of monocytes increased from 0.171(+/- 0.113) to 0.501(+/- 0.274) and 0.474(+/- 0.374) x 10(9)/l after 1 and 4 weeks of treatment (P less than 0.01). Other haematologic parameters did not change significantly. Two weeks post-treatment the numbers of neutrophils and monocytes had returned to pre-treatment values. Mild side effects consisting of bone, joint or muscle pain were observed in three patients. Two patients (both with AIDS) did not complete the study. One patient stopped treatment because of fever and malaise, attributable to a generalized cytomegalovirus (CMV) infection and one patient had to stop zidovudine treatment because of severe thrombocytopenia. We conclude that G-CSF increases the number of circulating neutrophilic granulocytes in zidovudine-treated patients at relatively low doses and with few side-effects.

Mechanism of protective effect of recombinant human granulocyte colony-stimulating factor (rG-CSF) on Pseudomonas infection

Decrease in resistance to systemic Pseudomonas infection in cyclophosphamide (CPA)-induced neutropenic mice was prevented by injections of recombinant human granulocyte colony-stimulating factor (rG-CSF). In order to explore mechanism of the prevention of CPA-induced decrease in the anti-infectious resistance by rG-CSF, CPA-treated and then rG-CSF-injected mice were inoculated i.p. with P. aeruginosa, and growth of the infecting bacteria and infiltration of leukocytes in the peritoneal cavity were determined. In the mice who had received 4 daily s.c. injections of rG-CSF from the day after CPA-injection, a large number of neutrophils were mobilized into the peritoneal cavity in response to the bacterial inoculation and growth of the infecting Pseudomonas in the cavity was markedly inhibited, whereas in CPA-induced neutropenic mice few neutrophils were mobilized and the infecting bacteria proliferated vigorously in the peritoneal cavity. These results suggest that administration of rG-CSF prevents CPA-induced neutropenia and neutrophils circulating at normal level in the number are normally mobilized into the peritoneal cavity in response to Pseudomonas inoculation, and that the mobilized neutrophils inhibit proliferation of the infecting Pseudomonas.

Therapeutic use of cytokines in dermatology

Cytokines are glycoproteins produced by many different cells. Via binding to specific receptors on target cells they regulate the activation, differentiation, and proliferation of immune and nonimmune cells. After injury keratinocytes synthesize and release cytokines such as interleukins, colony stimulating factors, and growth factors. In addition, a network of interacting cytokines appears to be crucial to maintain proper balance. Dysregulation may contribute to certain diseases, particularly those of infectious and autoimmune origin. Therefore many of these mediators appear to be promising candidates to treat infectious and malignant diseases. This article briefly discusses the most important cytokines. Newly developed regimens with cytokines to treat cutaneous disorders will be reviewed.

Clinical use of biologic response modifiers in cancer treatment: an overview. Part II. Colony-stimulating factors and interleukin-2

Colony-stimulating factors (CSFs) are hematopoietic growth hormones that stimulate the production, maturation, and function of white blood cells. The best studied are granulocyte-macrophage CSF (GM-CSF) and granulocyte CSF (G-CSF), both of which can be produced by recombinant DNA technology. Clinical indications for these agents include bone marrow failure secondary to administration of chemotherapeutic drugs or radiation, bone marrow transplantation, and a variety of congenital or iatrogenic neutropenias. Toxicity in usual clinical doses is mild, and consists mainly of bone pain and constitutional symptoms such as fever, headache, and myalgias. Interleukin-2 (IL-2) is a lymphokine that stimulates that multiplication of several types of killer cells. These cells can recognize and destroy foreign substances, such as tumors, without destroying normal cells. Major applications of IL-2 include treatment of patients with renal cell carcinoma, in whom the overall objective response rate is 15-30 percent, and malignant melanoma with response rates of about 18 percent. Combination therapy with other biologics and conventional cytotoxic drugs may increase IL-2's efficacy against these tumors. Toxicity is generally severe, but reversible. Hemodynamic toxicity, consisting of hypotension, edema, weight gain, and decreased renal function, is most characteristic. Suggestions are given for pharmacologic management of these and other IL-2 toxicities.

Haematological toxicity compromises MOPP/ABVD chemotherapy in Hodgkin's disease

A total of 23 patients with previously untreated Hodgkin's disease received MOPP/ABVD hybrid chemotherapy and response to treatment and toxicity were assessed. Of these 14 (61% (95% confidence limits 38.5%-80%] achieved complete remission with chemotherapy alone, six (26% (10.2%-48.4%)) achieved partial remission and there were three treatment failures (13%). Toxicity was mainly haematological resulting in treatment delays and dose reductions. Those in partial remission after chemotherapy achieved complete remission with additional radiotherapy. So far five of the 20 who remitted (25%) have relapsed. We conclude that the haematological toxicity from this regimen compromises dose intensity. The results from using this hybrid regimen are not superior to those using MOPP or ABVD alone in our experience.

Granulocyte colony-stimulating factor gene transfer suppresses tumorigenicity of a murine adenocarcinoma in vivo

We have investigated the effect of granulocyte colony-stimulating factor (G-CSF) delivery at the site of tumor growth by transducing, via retroviral vector, the human (hu) G-CSF gene into the colon adenocarcinoma C-26 and assaying the ability of transduced cells to form tumors when injected into syngeneic mice. As a control, the same tumor cells were infected with retroviruses engineered to transduce an unrelated gene, the human nerve growth factor receptor, or carry the neomycin resistance gene only. Only cells transduced with the huG-CSF were unable to develop tumors, although huG-CSF was expressed and produced at low level as estimated by both RNA analysis and enzyme-linked immunosorbent assay, indicating that G-CSF can exert an antitumor effect at a physiological dose. Implication of G-CSF as mediator of tumor inhibition was proven by reversing the nontumorigenic phenotype of G-CSF-expressing cells with anti-huG-CSF monoclonal antibody injected at the tumor site. No tumors were formed by injecting C-26 infected cells into nu/nu mice, while neoplastic nodules appeared after injection into sublethally irradiated mice; such tumors, however, regressed when mice normalized their leukocyte counts after irradiation. Tumors were also formed after injection of a mixture of infected and uninfected C-26 cells, although critical delay in tumor formation occurred when infected cells were 10 times more represented in the mixture. Histological examination of tissues surrounding the site of injection showed infiltration of neutrophilic granulocytes, whose number correlated with that of G-CSF-expressing C-26 cells in the injected mixture. These results indicate that G-CSF may have a potent antitumoral activity when released, even at low doses, at the tumor site. The antitumoral effect is mediated by recruitment and targeting of neutrophilic granulocytes to G-CSF-releasing cells.

In vivo tumor growth enhancement by granulocyte colony-stimulating factor

The intraperitoneal administration of human recombinant granulocyte colony-stimulating factor (G-CSF) enhanced the growth of intradermally inoculated tumor in mice; in a Meth A fibrosarcoma model, G-CSF administration significantly shortened the latency before tumor appearance, accelerated the increase of tumor size, shortened the survival time of tumor-bearing mice and increased the incidence of lethal tumor growth. A similar growth-enhancing effect of G-CSF was observed in models employing Meth 1 fibrosarcoma, colon carcinoma 26, and L1210 leukemia, although not all the effects were statistically significant. In vitro study showed that G-CSF did not enhance Meth A growth in suspension culture or in soft agar. These data suggest that G-CSF enhances the Meth A growth not directly but through the mediation of host factors. The accumulation of neutrophils was histologically observed in the tumor nodule, the blood, and the spleen in mice given G-CSF repeatedly. The spleen cells and the peripheral blood leukocytes of G-CSF-injected mice enhanced Meth A growth in vitro as compared with those of mice injected with physiological saline. These results suggest the possibility that the in vivo growth of tumor cells was enhanced by G-CSF-induced overproduction of cells including neutrophils.

Evaluation of recombinant canine granulocyte colony-stimulating factor as an inducer of granulopoiesis. A pilot study

Five healthy young adult dogs were given recombinant canine granulocyte colony-stimulating factor (rcG-CSF) at a dosage of 5 micrograms/kg/day subcutaneously for 4 weeks to evaluate the effect on complete blood cell counts. The mean neutrophil counts +/- standard deviation (SD) increased significantly (P less than 0.01) from 6,537/microliters +/- 1,726 (range, 4,950-9,512/microliters) to 26,330/microliters +/- 7,066 (range, 15,368-35,785/microliters) within 24 hours after the first injection of rcG-CSF. Mean monocyte counts +/- SD were significantly increased (P less than 0.05) from baseline values of 751/microliters +/- 168 (range, 444-891/microliters) to 2,514/microliters +/- 878 (range, 1,740-3,752/microliters) on day 5 of rcG-CSF administration. Mean neutrophil and monocyte counts (+/- SD) continued to increase reaching a maximum of 72,125/microliters +/- 15,073 (range, 50,915-96,278/microliters) and 3,972/microliters +/- 2,621 (range, 685-8,030/microliters), respectively by day 19. These increased neutrophil and monocyte counts were maintained until the administration of rcG-CSF was stopped. Blood counts returned to normal within 5 days after discontinuing the rcG-CSF. One week after discontinuing treatment, rcG-CSF was started again at 5 micrograms/kg/day subcutaneously. Within 48 hours following administration of rcG-CSF, mean neutrophil counts +/- SD increased from 5,860/microliters +/- 1,819 (range, 3,720-8,650/microliters) to 57,444/microliters +/- 8,173 (range, 43,983-68,278/microliters). Myeloid:erythroid ratios increased from a mean of 1.63:1 on day 1 prior to administration of rcG-CSF to 3.3:1 on day 10 in three dogs for which bone marrow samples were evaluated. Recombinant canine G-CSF did not cause clinically significant toxicosis in any of the dogs.

Whole body hyperthermia: a potent radioprotector in vivo

Interleukin-1 has been reported to be an effective radioprotective agent in mice subjected to lethal doses of irradiation. Production of Interleukin-1 can be increased by whole body hyperthermia. Therefore, whole body hyperthermia was assessed for its efficacy in protecting the lethal effects of ionizing radiation in DBA/2 mice. One hour of 40 degrees C +/- 0.2 whole body hyperthermia given 20 hr before 900 cGy total body irradiation protected 100% of DBA/2 mice from an LD 100/16 radiation dose (dose of irradiation that killed 100% of the mice in 16 days). Lethal doses of total body irradiation produced profound monocytopenia, decreased cellularity of thymus, spleen, and bone marrow, and suppressed Interleukin-1 production. Interleukin-1 production was determined using the thymocyte proliferation assay. Whole body hyperthermia accelerated recovery of blood leukocytes by up to 5 days post-total body irradiation in DBA/2 mice. Thymocytes, spleen, and bone marrow cells were activated by whole body hyperthermia, as assessed by the cell's response to Concanavalin A. This was accompanied by accelerated Interleukin-1 generation. Our results provide the first evidence that whole body hyperthermia acts as a potent radioprotector in vivo, effects that may be mediated by Interleukin-1.

Successful treatment of chronic idiopathic neutropenia using recombinant granulocyte colony-stimulating factor

A patient with chronic idiopathic neutropenia, who had been suffering from repeated infections, was successfully treated with recombinant granulocyte stimulating factor (rhG-CSF). Subcutaneous injection of 30 micrograms/m2 rhG-CSF every two days was sufficient to maintain the neutrophil count at approximately 1,000/microliter. The patient has lived without any evidence of infection for the last 10 months using that treatment. There were no side effect caused by rhG-CSF and antibodies against G-CSF were not detected in the patient's plasma.