Interferon administered in the cerebrospinal space and its effect on rabies in rabbits

Exogenous interferon prolongs survival of rabies infected mice

Rabies is an acute viral infection that causes encephalomyelitis in almost all warm blooded animals and is invariably fatal once the clinical signs appear. The present study was carried out to assess the effect of recombinant human interferon alpha (rhIFN α-2A) treatment on the survival of rabies infected mice and its correlation with cytokines expression. The gene expression of TNF-α and IL-6 was measured by SYBR Green Real Time PCR for two groups-"Pre-exposure" (mice were inoculated with rhIFN α-2A prior to rabies infection) and "Post-exposure" (mice were inoculated with rhIFN α-2A post rabies virus infection). Delayed mortality was observed in interferon treated infected groups. In addition, statistically significant decrease (P < 0.0001) in the expression of TNF-α and IL-6 was observed, both in the pre-exposure and post-exposure groups. These findings indicate that modulation of cytokine secretion using exogenous biologicals such as rhIFN may offer novel therapeutic approaches to treat diseases such as rabies.

Effect of vaccination and the immunomodulators "bacillus of Calmette-Guérin, avridine and Propionibacterium acnes" on rabies in mice

Responses of vaccination and treatment to immunomodulators against rabies in mice were evaluated through macrophage inhibition factor (MIF), intra-pad inoculation (IPI) and serum neutralization (SN) tests and by the detection of gamma-interferon (IFN-gamma). Onco-BCG, Avridine and Propionibacterium acnes were administered to groups of mice. Higher survival rates were found in animals treated with P. acnes. Lower levels of IFN-gamma were observed in the groups of infected and vaccinated mice. The IPI was not effective on detecting the response of delayed-type hypersensitivity. Vaccine induced in the infected animals a more intense response to MIF reaction.

Recombinant interferon-gamma applied to the brain ventricular system protects rats against pseudorabies

We examined the prophylactic efficacy of recombinant rat interferon-gamma (IFN-gamma) administered directly into the brain ventricular system or via the intraperitoneal (i.p.) route against central and peripheral pseudorabies virus (PRV) infection. Intraperitoneally given IFN-gamma completely protected rats against a lethal i.p. PRV infection. The same regimen showed no protective effect against lethal intracerebroventricular (i.c.v.) PRV challenge even if IFN-gamma was given in high concentrations. When given via the i.c.v. route, IFN-gamma protected rats against lethal i.c.v. infection and also evoked partial protection with extended survival times of i.p. infected rats. Our results demonstrate an IFN-gamma-mediated antiviral effect in the central nervous system.

The effect of intraventricular interferon on subacute sclerosing panencephalitis

Two patients with subacute sclerosing panencephalitis (SSPE) were treated with intraventricular alpha interferon (IFN-alpha) via an Ommaya reservoir for 20-57 months. The clinical course of the disease was followed for 20-67 months. Clinical improvement was observed after daily intraventricular administration of IFN in one case. There were no serious complications or side effects during interferon therapy except for the fever. Intraventricular administration of IFN appears superior to intrathecal administration for long-term treatment in several respects and is considered to be a potential therapeutic modality for SSPE.

Oligoclonal "fingerprint" of CSF IgG in multiple sclerosis patients is not modified following intrathecal administration of natural beta-interferon

The IgG pattern in CSF was studied in 11 patients with multiple sclerosis who exhibited an oligoclonal banding upon thin-layer polyacrylamide gel isoelectric focusing followed by silver stain of unconcentrated CSF. Each patient received beta-interferon intrathecally during a 2 month period. No modification was observed over a 6 month period. In addition, the oligoclonal pattern was remarkably unique for each individual representing a typical "fingerprint" which allowed the identification of any single CSF.

Use of interferon in the management of patients with subacute sclerosing panencephalitis

Six patients (five male, one female) with subacute sclerosing panencephalitis were treated with purified lymphoblastoid interferon, using a combination of intravenous and lumbar intrathecal routes. The first symptoms of the disorder occurred between seven and 16 years of age, and the length of the illness before treatment varied from 1 1/2 to 12 months. All six patients were in the first clinical stage of the disorder. After a limited period of follow-up there has been no clinical improvement. Nil or low levels of interferon were found in CSF two hours after intravenous injection, but CSF levels of interferon were maintained for at least 24 hours after intrathecal injections. Side-effects of interferon included pyrexial reactions, especially after high-dose intravenous therapy (six), lethargy (four), a transient rise in blood pressure (two) and a reduction in platelet count (six). Staphylococcus epidermidis was grown from the CSF of one patient.

Phase I clinical trial of intralesional or intraventricular leukocyte interferon for intracranial malignancies

Eight patients were treated with leukocyte interferon for a variety of neurological malignancies that had failed or recurred after conventional therapy. Three patients with malignant astrocytoma received intratumoral interferon in dosages up to 9 million units 3X/week, with total dosages of up to 160 million units. Interferon was administered intraventricularly in 4 patients with leptomeningeal metastases and one patient with multiple brain metastases. Dosages increased from 1 to 10 million units 3X/week, and total dosages of up to 113 million units were given intraventricularly. Acute side effects of fever, nausea, vomiting, and headache occurred almost exclusively with intraventricular injections, and these subsided after the initial injection. Fatigue, loss of appetite, weight loss, and hematologic toxicity developed a few weeks after onset of treatment, independent of the dose given. A modest tumor regression was seen on CT scans of one patient with a malignant astrocytoma, who was treated with interferon for 8 months. In all 4 patients with leptomeningeal metastases, the CSF became free of malignant cells for 6 to 10 weeks, while clinical improvement was less dramatic.

Human leukocyte interferon administration to patients with symptomatic and suspected rabies

Body fluids and brain tissue from rabid human patients have demonstrated only low titers of interferon. Therefore, pharmacokinetic studies of systemically administered and locally injected leukocyte interferon were performed in 2 North American patients with suspected rabies who showed no clinically important side effects of this therapy. Similar therapy was given to 5 patients with symptomatic rabies in Europe and America. Although no prolongation of the clinical course was seen in 3 patients given high-dose intraventricular and systemic therapy, treatment was not initiated until between 8 and 14 days after symptoms were seen. The intraventricular dosage regimen produced cerebrospinal fluid levels that appeared to fall progressively over the 24 hours after injection and demonstrated good but somewhat delayed distribution into the lumbar sac. Titers produced by this therapy were 30- to 10,000-fold higher than those normally observed in this infection, however. In the patients treated at the highest dosage, a diminished and delayed antirabies neutralizing antibody titer was observed, probably a result of the administration of the exogenous interferon.

Clinical effect of interferon in malignant brain tumours

Phase I and phase II clinical studies of interferon (IFN) were conducted in malignant brain tumours (47 cases of glioblastoma, medulloblastoma and others) using three preparations of the drug. The drug was administered daily in doses 3.0 - 9.0 X 10(6) I.U. locally or intravenously (beta-type) or intramuscularly (alpha-type). The administration was continued as many days as possible, eight weeks being the shortest period. The efficacy of the therapy was assessed mainly by the CT findings (computed volume of the tumour). As for efficacy against glioblastomas, the highest effectiveness rate (40%) was obtained with Human Fibroblast IFN (HFIF) (beta-type) (Toray) (one case of complete remission and seven cases of partial remission out of 20 cases) as compared to Human Lymphoblastoid IFN (HLBI) (alpha a-type) (Wellcome) (one case of partial remission out of three cases) and recombinant IFN (rIFN-alpha A) (alpha-type) (Roche) (two cases of partial remission out of nine cases). The high rate of responsiveness of HFIF seems to be largely attributable to the local, rather than systemic, administration of the drug. Our pharmacokinetic study revealed that, by means of intrathecal administration a much higher IFN titre was detected in the cerebrospinal fluid, while by intravenous or intramuscular route, the IFN titre in the CSF was undetectably low. The generally lower incidence of side-effects with HFIF compared to other preparations was also largely ascribable to the route of administration. IFN therapy in combination with radiotherapy and/or chemotherapy should also be investigated.

Adjuvant interferon treatment and the late development of cerebral metastases in a patient with osteosarcoma

A consecutive series of patients with osteocarcoma have been receiving adjuvant interferon therapy at the Karolinska Hospital in Stockholm. We report here a case of tibial chondroblastic Grade III osteosarcoma, a boy aged 17 years, who received interferon therapy for 15 months and survived more than 5 years. The first sign of tumour spread was multiple cerebral metaseases--an observation suggesting an antitumour effect of human leucocyte interferon on osteosarcoma.

Intramuscular and/or intralumbar postexposure treatment of rabies virus-infected cynomolgus monkeys with human interferon

From 9 to 10 of 10 cynomolgus monkeys infected with rabies street virus died of rabies about 20 days postinfection (pI). Symptoms of illness appeared 1 to 4 days before death. In an attempt to protect infected animals from the disease, human leukocyte interferon (HIF) was administered intramuscularly (i.m.) near the site of infection or into the cerebrospinal fluid between the first and second lumbar vertebrae (i.e., intralumbarly [i.l.]). Multiple HIF doses given over a period of several days proved more effective than a single HIF dose. In every experiment, i.m. HIF treatment was started 1 day pI. The best result obtained was a survival rate of 7 of 10 monkeys. The i.l. HIF administration schedules, consisting of multiple doses given over a period of at least 8 days, were started on day 3, 7, or 11 pI. Here the best result noted was the protection of 5 of 10 treated monkeys. The latest successful postexposure i.l. HIF treatment began on day 11 pI. The highest protection rate, 8 survivors of 10 treated monkeys, was achieved by a combined i.m. and i.l. HIF treatment. From these results we conclude that human patients severely bitten by rabid animals should in addition to an active immunization be i.m. and i.l. treated with HIF. Particularly, i.l. HIF administration could be effective, even when given several days pI. Whether an HIF administration starting after the appearance of clinical symptoms of rabies can help cannot be decided upon from the studies made in this monkey model. The most obvious difference between rabies in humans and cynomolgus monkeys is the duration of illness between the outbreak of the disease and death (1 to 4 days only in this animal model). It might have been due to this short period of illness that i.l. and i.m. HIF treatment at the appearance of clinical symptoms failed to help any of the monkeys treated.

Systemic and topical use of poly I.C. in treatment of generalized neonatal herpes simplex infection with severe ocular involvement

A case of Neonatal Herpes Simlex Virus (RSV) Encephalitis with severe ocular manifestation treated by topical systemic and intrathecal Interferon inducer, Poly IC (Polyriboinosinic acid-Polyribocytidylic acid) is reported. Prior to the administration of Poly IC, no Interferon could be detected neither in blood nor in CSF and vesicular fluid from conjunctiva. Intravenous administration of the drug initiated measurable levels in blood and tears, but not in CSF. However, intrathecal injection induced persistent high levels of Interferon in CSF. Virus clearance from conjunctiva tears and vesicular fluid occurred after three days of topical application of Poly IC. The mechanism of action of Poly IC, the laboratory results and the therapeutic conclusions are discussed in detail. This is the first report of intrathecal administration of Poly IC in a case of HSV Encephalitis.

Effect of administered human interferon on experimental rabies in monkeys

Cynomolgus monkeys infected with rabies virus were protected by repeated intramuscular administration of human leukocyte interferon beginning 24 h after infection.