Human recombinant interferon gamma enhances neonatal polymorphonuclear leukocyte activation and movement, and increases free intracellular calcium.

In previous studies, we have reported that after chemotactic factor stimulation, PMNs from neonates fail to undergo certain critical activation steps. Furthermore, the concentration of free intracellular calcium reached is significantly below that of PMNs from adults. Interferon-gamma (IFN-gamma) is a lymphokine that has been shown to activate phagocytic cells, and IFN-gamma messenger RNA production by neonatal mononuclear leukocytes has been reported to be depressed. In the present studies, we found that recombinant human IFN-gamma markedly enhanced the chemotactic responses of PMNs from neonates to levels that were not different from that of PMNs from adults. Furthermore, preincubation of the neonatal cells with this recombinant human lymphokine also corrected the abnormality in intracellular calcium metabolism. These results suggest that this developmental defect in phagocytic cell movement may be the result of an intrinsic defect in IFN-gamma production resulting in deficiency of this critical phagocyte-activating lymphokine.

Organ specific cytokine therapy. Local activation of mononuclear phagocytes by delivery of an aerosol of recombinant interferon-gamma to the human lung.

In the context of the central role of the alveolar macrophage in host defense of the respiratory epithelial surface, and the ability of IFN-gamma to activate mononuclear phagocytes, we have evaluated strategies to use rIFN-gamma to activate human alveolar macrophages in vivo. To accomplish this, rIFN-gamma was administered to nonsmoking normals, the amounts of IFN-gamma quantified in serum and respiratory epithelial lining fluid (ELF) and the status of IFN-gamma related activation of blood monocytes and alveolar macrophages was evaluated by quantifying the expression of mRNA transcripts of IP-10, a gene induced specifically by IFN-gamma. Systemic administration (subcutaneous) of maximally tolerated amounts of rIFN-gamma (250 micrograms) was followed by detectable levels of IFN-gamma in serum but not ELF, the expression of IP-10 transcripts in blood monocytes but not alveolar macrophages, and multiple systemic adverse effects. To circumvent the inability of systemic administration to reach respiratory ELF and activate alveolar macrophages, rIFN-gamma (250-1,000 micrograms) was inhaled as an aerosol once daily for 3 d. Strikingly, while IFN-gamma was not detected in serum it was detectable in respiratory ELF in a dose-dependent fashion. Further, alveolar macrophages, but not blood monocytes, expressed IP-10 mRNA transcripts and, importantly, inhalation of aerosolized rIFN-gamma was not associated with local or systemic adverse effects. Thus, it is feasible to use rIFN-gamma to activate alveolar macrophages by targeting the cytokine directly to the lung. These data suggest a potential strategy for targeted cytokine therapy, without systemic side effects, to augment respiratory tract defenses in individuals at risk for or with lung infection.

Circulating cytokines in patients with metastatic cancer treated with recombinant interleukin 2 and lymphokine-activated killer cells.

Treatment with recombinant interleukin 2 and lymphokine-activated killer cells (rIL-2/LAK) has produced a clinical antitumor effect in preliminary human trials. The cytokines gamma-interferon (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), and tumor necrosis factor beta (TNF-beta, lymphotoxin) have potent in vitro antitumor activity and some clinical toxicities similar to interleukin 2 (IL-2)/LAK. This study sought to determine whether these cytokines were detectable in sera of IL-2/LAK-treated patients. Ten patients were treated with a protocol of 5-day i.v. rIL-2 bolus priming (10(5) units/kg, every 8 h), followed by 5 daily phereses with harvested lymphocytes cultured in vitro to generate LAK, and 5 days of rIL-2 bolus with infusion of LAK cells. Five patients were treated with a protocol modified to a 3-day rIL-2 prime and 6-day continuous infusion rIL-2 (3 x 10(6) units/m2/day) with infusion of LAK cells. Serum specimens were obtained prior to and 0.5, 2, 3, and 5 h after IL-2 or LAK cell administrations. IFN-gamma was detected by enzyme-linked immunosorbent assay, TNF-alpha by WEHI 164 bioassay or enzyme-linked immunosorbent assay, and TNF-beta by WEHI 164 cell bioassay. During the prime, few patients manifested in vivo detectable serum cytokines: IFN-gamma, three of ten, 5-day prime (1.03 +/- 0.46 ng/ml), and zero of five, 3-day prime; TNF-alpha, one of ten, 5-day prime, and one of three, 3-day prime; TNF-beta, one of ten, 5-day prime. The supernatants of in vitro LAK generation cultures had detectable levels of cytokines at 24 h which increased progressively until culture harvest at Day 4 (IFN-gamma, 2.56 +/- 0.34 ng/ml; TNF-alpha, 356 +/- 110 pg/ml; TNF-beta, 8.2 +/- 4.4 units/ml). The highest levels of in vivo serum cytokines occurred following LAK cell infusion and were more often elevated in patients receiving rIL-2 by bolus than by continuous infusion: IFN-gamma, four of six bolus, zero of three continuous infusion; TNF-alpha, six of six bolus (maximum 679 pg/ml) versus two of three continuous infusion (maximum, 106 pg/ml). LAK cells in vitro responded with cytokine release on stimulation by tumor cell lines (IFN-gamma, 0.88 +/- 0.06 ng/ml; TNF-alpha, 426 +/- 16 pg/ml; TNF-beta, 0.64 +/- 0.06 units/ml). In summary, this preliminary study has detected circulating cytokines in sera of patients receiving IL-2/LAK therapy. The greatest cytokine elevations followed LAK cell infusion.(ABSTRACT TRUNCATED AT 400 WORDS)

Interleukin-2 and lymphokine-activated killer cell therapy of solid tumors: analysis of toxicity and management guidelines.

The National Cancer Institute (NCI) Extramural IL2/LAK Working Group treated 93 patients with 114 cycles of high-dose intravenous (IV) interleukin-2 (IL-2) and lymphokine-activated killer (LAK) cells in three phase II trials. Thirty-six patients had metastatic melanoma, 35 had metastatic renal cell cancer, and 22 had colorectal cancer. All patients had a Karnofsky performance status greater than or equal to 80% and normal laboratory tests and organ function, and had received no more than one prior form of immunotherapy or chemotherapy. Objective responders were eligible to receive up to two additional courses of therapy at 12-week intervals. The most frequent toxicities were a capillary leak syndrome resulting in marked extravascular fluid shifts, and hypotension requiring treatment with large volumes of IV fluids and vasopressor agents. Laboratory and clinical evidence of hepatic and renal dysfunction were virtually universal. Intensive care-level support was routinely provided and the toxicity observations confirmed the need for this level of care. The life-threatening toxicities were cardiac and pulmonary. Five of the 27 patients who experienced significant respiratory compromise required intubation and mechanical ventilatory support. Twenty patients developed cardiac arrhythmias, the majority of which were supraventricular. There was a single episode of ventricular tachycardia requiring cardioversion. Four patients had transient cardiac ischemia, and an additional four had myocardial infarctions, one of which was fatal. With these exceptions, all toxicities were rapidly reversible. The occurrence of only a single therapy-related death and a very low incidence of other irreversible or life-threatening events is comparable to the level of toxicities often observed in other phase II trials. Although the intensity of this regimen limits this approach to a subset of cancer patients with excellent performance status and adequate organ function, because of the frequency and apparent durability of complete responses, this treatment warrants further investigation.

Phase I study of recombinant human interferon gamma in children with relapsed acute leukemia.

Fourteen children (ages 2-15 years) with acute leukemia in relapse were treated with daily recombinant interferon gamma for 14 days by subcutaneous injections at fixed dose levels of 0.1, 0.25, 0.5, or 0.75 mg/m2 (1.0, 2.5, 5.0, or 7.5 x 10(6) units/m2) without intrapatient escalation. Patients received a second 14-day course of therapy followed by thrice weekly administration unless there were signs of progressive disease or grade 3 or 4 toxicity. Side effects in the 13 evaluable patients included fever (n = 10), fatigue (9), decreased Karnofsky performance score (8), hypertriglyceridemia (8), myalgia (5), weight loss > 5% (4), elevated liver transaminases (4), and abdominal pain (3). There was only one grade 4 toxicity: one of the six patients at the 0.5 mg/m2 dose level developed reversible acute renal failure. One patient died of gastrointestinal hemorrhage due to disease-related refractory thrombocytopenia. One child had an oncolytic response and two others stable disease for 138 and 148 days. An appropriate dose level for phase II studies in children is 0.5 mg/m2 per day.

Recombinant gamma interferon in treatment of patients with atopic dermatitis and elevated IgE levels.

PURPOSE: Recombinant gamma interferon (rIFN-gamma) inhibits IgE synthesis in vitro by human peripheral blood mononuclear cells (PBMC). These data suggest a role for rIFN-gamma in the treatment of patients with severe atopic dermatitis (AD) and elevated IgE levels. The purpose of this study was to determine the effect of rIFN-gamma treatment on IgE production in patients with AD. PATIENTS AND METHODS: Twenty-two patients with chronic severe AD were treated with rIFN-gamma. In part I of the study, 14 patients were treated with daily subcutaneous injections at three successive dose levels (0.01 mg/m2, 0.05 mg/m2, and 0.1 mg/m2) for 5 days with 2 days off between each dose level. In part II, eight patients received rIFN-gamma at 0.05 mg/m2, daily for 6 weeks. One patient from part I and eight patients from part II of the study received three times per week maintenance thereby for up to 14 months. Prior to and at selected times during and after treatment, the clinical and immunologic status of the patients was assessed. RESULTS: In part I, spontaneous de novo IgE synthesis by PBMC was inhibited in 10 patients receiving rIFN-gamma at 0.01 mg/m2 (p = 0.038) and in nine at 0.1 mg/m2 (p = 0.066). There was no reduction of serum IgE levels at any of the three dose levels. Total clinical severity showed improvement at each dose level (p less than 0.04) with worsening 3 days after discontinuation of treatment. In part II, there was no significant inhibition of spontaneous IgE synthesis by PBMC nor was there any reduction of serum IgE. Nevertheless, there was a progressive and significant reduction (p less than 0.01) in total clinical severity over the 6 weeks of daily rIFN-gamma with a sustained improvement during maintenance therapy. CONCLUSION: The results of this pilot study suggest that rIFN-gamma may be efficacious in the treatment of AD and that further clinical trials are warranted.

A randomized, double-blind, phase I/II trial of tumor necrosis factor and interferon-gamma for treatment of AIDS-related complex (Protocol 025 from the AIDS Clinical Trials Group).

To determine safety and efficacy of tumor necrosis factor (TNF) and interferon-gamma (IFN gamma) in the treatment of patients with acquired immunodeficiency syndrome (AIDS)-related complex, a randomized, double-blind study was conducted. Twenty-five patients with AIDS-related complex and CD4 lymphocytes less than or equal to 500 x 10(6)/L attended an AIDS Clinical Trials Unit of a tertiary referral center. Patients were administered tumor necrosis factor (TNF) (10 micrograms/m2) or IFN gamma (10 micrograms/m2), or both intramuscularly three times weekly for 16 weeks. Side effects from all three preparations included fever, constitutional symptoms, and local reactions. No significant hematologic, hepatic, renal, or coagulation abnormalities were observed. CD4 lymphocyte counts, beta 2-microglobulin, p24 antigen levels, and anti-p24 antibody did not change significantly during therapy. Similarly, no significant change was noted in rates of HIV isolation from peripheral blood mononuclear cells or plasma. TNF and IFN gamma were tolerable after premedication with acetaminophen; however, no significant change in markers of human immunodeficiency virus infection was demonstrated. These cytokines alone do not appear to be of benefit, nor do they appear to hasten the progression of HIV infection.

Pharmacokinetics, safety and bioavailability of HPMPC (cidofovir) in human immunodeficiency virus-infected subjects.

We conducted a single-center, double-blind, placebo-controlled phase I study in HIV-positive subjects to ascertain the safety, tolerance, bioavailability, pharmacokinetics, and maximum tolerated dose of HPMPC (cidofovir). Five subjects were randomized to receive drug and two to receive placebo at each of three dosage tier (1, 3, and 10 mg/kg) with a 2-week washout period doses. Subjects at 1 and 3 mg/kg received single doses of HPMPC by subcutaneous (s.c.) intravenous (i.v.), and oral (p.o.) routes, while subjects at 10 mg/kg received only i.v. and p.o. doses. For subjects already taking zidovudine, zidovudine AUC values are determined before and then with HPMPC administration for each route. The AUC values of HPMPC were dose-proportional. Subcutaneous bioavailability was essentially equivalent to that of the intravenous route, but the development of transient local fibrosis ad the volumes needed for subcutaneous dosing precluded higher subcutaneous dosing than 3 mg/kg. Oral bioavailability was poor, estimated to be less than 5%. Drug elimination was predominantly renal. Nephrotoxicity in one subject was the only serious adverse event observed. This subject had a significant lag period prior to oral absorption and also had the highest AUC values for both HPMPC and zidovudine. We found no consistent effect on zidovudine AUC concomitant HPMPC.

A controlled trial of intralesional recombinant interferon-gamma in the treatment of keloidal scarring. Clinical and histologic findings.

Interferon-gamma (IFN-gamma) suppresses the synthesis of collagen by fibroblasts in vitro and the synthesis of collagen in vivo in animal models. Therefore, recombinant human IFN-gamma was examined for its ability to clinically modify keloids. Subjects were treated by injection of either 0.01 or 0.1 mg of recombinant human IFN-gamma into one lesional site and diluent alone into another lesional site three times per week for 3 weeks. Keloids were measured and photographed before beginning therapy and weekly thereafter. Three days after the final injection, biopsies were performed on treated and control sites. Six of eight subjects who finished the course of treatment demonstrated reduction in size at the treated site with an average reduction in height of 30.4% vs 1.1% for control sites. Lesions treated with recombinant human IFN-gamma demonstrated alterations in both the epidermis and dermis. The epidermis showed thinning of the suprapapillary plates, compact hyperkeratosis, focal or diffuse parakeratosis, exocytosis of lymphocytes, and an increased quantity of mucin. The dermis contained a diminished quantity of thickened collagen bundles and active fibroblasts and an increased number of inflammatory cells and quantity of mucin. These results suggest the feasibility of using IFN-gamma in the treatment of abnormal fibrosis. Dose-ranging studies are required to establish whether IFN-gamma can fulfill a true clinical need in the treatment of keloidal scarring.

A randomized prospective clinical trial to determine the efficacy of interferon-gamma in severely injured patients.

Many aspects of the normal immune response are depressed after severe injury. Reduced monocyte human leukocyte antigen-DR (HLA-DR) levels have closely correlated with the development of major infection. After a pilot study with recombinant interferon-gamma (rIFN-gamma) showed restoration of depressed HLA-DR levels after major injury, a multicenter, prospective, randomized, double-blind trial was conducted. Two hundred thirteen trauma patients who were at high risk of infection received either placebo or rIFN-gamma (100 micrograms) subcutaneously each day for 10 days after admission. One hundred ninety-three patients were evaluable with respect to primary end points. Patients treated with rIFN-gamma were older (p = 0.10) and had more severe modes of injury (p = 0.02). By the third day, both monocyte HLA-DR antigen expression and outcome predictive score were significantly better in the rIFN-gamma-treated group than in the placebo group (p = 0.0001 and p = 0.0006, respectively). Nine deaths occurred in patients treated with rIFN-gamma compared with 12 deaths in the placebo group (p = 0.46). Major infections requiring surgical drainage or debridement occurred in 17 patients treated with rIFN-gamma compared with 22 treated with placebo. No difference between treatment arms was noted in overall major or minor infection rates, but there were fewer severe infections that required reoperation or computer tomographic-guided drainage in patients receiving IFN-gamma. While these results suggest that rIFN-gamma may be useful in some aspects of infection in the patient with severe trauma, a larger trial with longer treatment will be needed to prove the comprehensive value of rIFN-gamma.

Intralesional interferon gamma treatment for keloids and hypertrophic scars.

Keloids and hypertrophic scars are characterized by excessive collagen formation. Interferon gamma is a lymphokine that can down-regulate collagen synthesis in vitro and in vivo and, therefore, has potential therapeutic benefit in the management of abnormal scars. Intralesional scar injections of interferon gamma were performed to determine the tolerance toxicity and to obtain preliminary evidence for the efficacy of this treatment in the management of hypertropic and keloid lesions. All scars decreased in linear dimensions and flattened out. Five of 10 scars studied decreased at least 50% in linear dimensions. Interferon gamma can safely be administered intralesionally once per week up to a dosage of 0.05 mg for 10 weeks with no serious toxic effects. The commonest reported side effect was a mild headache.

Use of recombinant human interferon gamma to enhance neutrophil chemotactic responses in Job syndrome of hyperimmunoglobulinemia E and recurrent infections.

Recombinant human interferon gamma enhances neutrophil respiratory burst and bactericidal activity in patients with chronic granulomatous disease. Mononuclear leukocytes of patients with the hyperimmunoglobulinemia E syndrome (Job syndrome) produce low or undetectable levels of this lymphokine. For these reasons we have restudied neutrophil chemotaxis in a group of our patients with the syndrome and determined the effect of recombinant human interferon gamma on the responses. Each of the patients had neutrophil chemotactic responses ranging from 22% to 55% of simultaneous control values (p less than 0.001). After incubation with interferon gamma, a significant improvement in chemotactic responsiveness was observed in the neutrophils of each of the patients (mean 301% of baseline chemotaxis; p less than 0.008). These data suggest the need for a double-blind, placebo-controlled trial of interferon gamma in a larger group of patients with the syndrome of hyperimmunoglobulinemia E and recurrent infections.

Recombinant human interferon-gamma as adjunct therapy for Aspergillus infection in a patient with chronic granulomatous disease.

The hallmark of chronic granulomatous disease (CGD) is defective killing of ingested microorganisms by phagocytic cells. Invasive aspergillosis in CGD patients is particularly virulent and has a mortality rate of approximately 50%. A patient with autosomal recessive CGD was identified who had progressive pulmonary aspergillosis that was unresponsive to conventional antifungal therapy. She was treated with recombinant human interferon-gamma (rHuIFN-gamma) and had a dramatic improvement in clinical symptoms, sedimentation rate, and radiographic scans. No consistent improvement in bactericidal function or neutrophil oxidative capacity could be demonstrated. However, serum neopterin levels, a measure of macrophage activation, increased in a dose-dependent manner with rHuIFN-gamma therapy; increased levels mirrored the improved clinical parameters. This patient's treatment illustrates the usefulness of the single-photon emission computed tomography (SPECT) gallium scan for following pulmonary inflammatory lesions in the presence of fibrosis and indicates that rHuIFN-gamma may be of benefit to CGD patients with serious infections unresponsive to conventional therapy.

Prolonged recombinant interferon-gamma therapy in chronic granulomatous disease: evidence against enhanced neutrophil oxidase activity.

Recombinant interferon-gamma (rIFN-gamma) therapy has become an effective form of prophylaxis for patients with chronic granulomatous disease (CGD). Preliminary studies with CGD suggested that rIFN-gamma treatment enhanced phagocyte oxidase activity and increased superoxide (O2-) production. We evaluated several aspects of neutrophil NADPH oxidase activity in 19 CGD patients (representing all four known types of CGD) receiving prolonged rIFN-gamma therapy (6 to 27 months). In contrast to earlier studies, we failed to detect any improvement in neutrophil NADPH oxidase activity in 18 of the 19 CGD patients as determined by (1) intact cell O2- production (continuous assay), (2) nitroblue tetrazolium (NBT) staining, (3) cytochrome b558 spectroscopy, and (4) activity levels of cytosol and membrane oxidase components using a cell-free activation system. One patient with a variant form of X-linked CGD had a transient increase in neutrophil O2- production following 3 months of rIFN-gamma therapy. However, this was not sustained, and was not associated with any change in cytochrome b levels. In some patients, rIFN-gamma therapy was associated with the appearance of a small subset of circulating monocytes (1% to 20%) that were NBT-positive. Although the functional significance of this monocyte subpopulation needs to be determined, these results suggest that one possible mechanism by which rIFN-gamma may benefit CGD patients is by partially correcting the respiratory burst defect in a subset of monocytes. We conclude that the clinical benefit of prolonged rIFN-gamma therapy in the vast majority of CGD patients is not due to enhanced neutrophil NADPH oxidase activity. The mechanism of action of rIFN-gamma in most CGD patients remains unknown.

Pretreatment hematocrit as an independent prognostic variable in Hodgkin's disease.

Pretreatment hematocrit in 117 advanced-stage Hodgkin's disease patients treated with a combined modality therapy program was evaluated as an independent prognostic variable with regard to survival and relapse-free survival. Age greater than 40 years, and multiple extranodal sites of involvement were found to be statistically significant independent negative prognostic factors with regard to survival. Pretreatment hematocrit, however, was not an independent negative prognostic variable.

Complications of co-trimoxazole in treatment of AIDS-associated Pneumocystis carinii pneumonia in homosexual men.

In 8 of 18 homosexual men with the acquired immunodeficiency syndrome (AIDS) and Pneumocystis carinii pneumonia (PCP) treated with intravenous co-trimoxazole (trimethoprim-sulphamethoxazole) apparent drug-related complications developed during the course of acute therapy. A symptom complex of fevers and increasing malaise, often with nausea and headaches, developed usually after 9 days of therapy at a daily dosage of 20 mg/kg of trimethoprim and 100 mg/kg of sulphamethoxazole. These symptoms were associated with a diffuse erythematous maculopapular eruption and peripheral cytopenias. A similar picture was noted in two children with suspected AIDS-associated PCP. The high frequency of adverse reactions to co-trimoxazole therapy for PCP seems to be characteristic of AIDS patients.

Partial correction of the phagocyte defect in patients with X-linked chronic granulomatous disease by subcutaneous interferon gamma.

Chronic granulomatous disease, a disorder of host defense, is characterized by an impairment in the killing of microbes that results from a defect in the production of superoxide anion by phagocytes. We examined the efficacy of interferon gamma, a physiologic activator of phagocytic-cell function, in the treatment of the disease. Two subcutaneous injections of recombinant interferon gamma (0.1 mg per square meter of body-surface area per dose) were administered on consecutive days to four patients with the X-linked form of the disease. Treatment resulted in 5- to 10-fold increases in superoxide production by granulocytes and monocytes; the improvement was sustained for more than two weeks. Granulocyte bactericidal activity rose proportionally. In the two most responsive patients, both phagocytic functions reached the normal range of activity. In association with these functional changes, we observed an increase in cellular contents of phagocyte cytochrome b (a critical component of the superoxide-producing oxidase) and immunoreactive cytochrome b heavy chain (the product of the gene that is defective in X-linked chronic granulomatous disease). Levels of cytochrome b detected by spectrophotometry rose from near zero to 10 to 50 percent of normal values. This study demonstrates partial correction of the cellular defects in chronic granulomatous disease by interferon gamma and provides a basis for clinical trials of the agent.