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Biomedical subjects

H B Levy

Publications and source records attributed to H B Levy.

At least 73 records · Page 4Linked to original sources
PubMed1979

Further studies on rabies postexposure prophylaxis in mice: a comparison of vaccine with interferon and vaccine.

Mice were inoculated in the left hind footpad with street rabies virus, and 24 h later various types of rabies vaccine were administered intramuscularly in the right leg. The vaccines alone were ineffective in reducing mortality, but when an interferon inducer, polyriboinosinic acid-polyribocytidylic acid complexed to poly-L-lysine (polyICLC), was given along with the vaccines, a marked reduction resulted. The polyICLC-vaccine combination was effective even when it was injected 5 days after infection, suggesting that effective postexposure treatment in man might be successful when given at a comparable late time.

Animals↗
PubMed1979

Adjuvant effects of low doses of a nuclease-resistant derivative of polyinosinic acid . polycytidylic acid on antibody responses of monkeys to inactivated Venezuelan equine encephalomyelitis virus vaccine.

Polyriboinosinic.polyribocytidylic acid [poly(I).poly(C)] stabilized with poly-l-lysine and carboxymethylcellulose [poly(ICLC)] has been previously shown to be a compound with marked adjuvant activity when given in high doses with inactivated Venezuelan equine encephalomyelitis (VEE) virus vaccine. This study investigated the effects of much lower doses of poly(ICLC) on the magnitude and kinetics of the primary and secondary humoral antibody responses of rhesus monkeys to inactivated VEE virus vaccine. Monkeys given a single injection of vaccine developed very low neutralizing antibody titers, whereas those given adjuvant plus vaccine had 30- to 100-fold-higher titers which remained elevated for longer than 6 months. Low doses of poly(ICLC) given with VEE virus vaccine resulted in a profound but transient increase in priming of secondary antibody responses to the antigen. In contrast, the administration of poly-l-lysine and carboxymethylcellulose alone without the poly(I).poly(C) component of the complex had no adjuvant effect on antibody responses of monkeys to VEE virus vaccine. The temporal development of antibody by class (immunoglobulin M-immunoglobulin G) in monkeys given two injections of adjuvant-vaccine was not different from that with vaccine alone. Serial hematological and clinical chemistry determinations on monkeys given single or multiple doses of poly(ICLC) with vaccine were not different from values in monkeys given vaccine alone.

Adjuvants, Immunologic↗
PubMed1979

Modified polyriboinosinic-polyribocytidylic acid complex: sustained interferonemia and its physiological associates in humans.

Fourteen patients with severe viral illnesses were given intravenous infusions of a modified interferon inducer, polyriboinosinic-polyribocytidylic acid-poly-L-lysine complexed with carboxymethylcellulose [poly)I:C.LC)], during a phase 1 clinical trial. The first eight patients received 0.15 to 0.30 mg of poly(I:C.LC) per kg of body weight daily for 5 consecutive days, and another received two courses separated by 1 week. A second group of five patients was given single intravenous infusions of 0.10 to 0.15 mg of poly(I:C.LC) per kg. Interferon was detectable in the serum 8 to 16 h after injection. Titers ranged from 15 to 800 U/ml and varied directly with the dose of poly(I:C.LC). Interferonemias persisted for 12 to 48 h. In patients receiving 5-day courses of poly(I:C.LC), lower levels of serum interferon (0 to 160 U/ml) occurred on days 2 through 5, characteristic of a hyporesponsive state. An exception was a 69-year-old patient with disseminated varicella zoster, multiple myeloma, and renal insufficiency whose serum contained 3,150 U of interferon per ml on day 3 of 0.3 mg of poly(I:C.LC) per kg. Fever (39 to 40.5 degrees C, rectally; 13 of the 14 patients) peaked 3 to 8 h after completion of infusions. Other toxic effects included lymphopenia (10 of the 14 patients), hypotensive episodes (7 of the 14 patients), and minor elevations of serum glutamicoxalacetic transaminase and lactic dehydrogenase.

Adolescent↗
PubMed1979

An effective rabies treatment in exposed monkeys: a single dose of interferon inducer and vaccine.

Rhesus monkeys were injected with lethal doses of rabies virus and then treated with a variety of treatment combinations. The one found most successful was one dose of an interferon inducer (poly(I)-poly(C) complexed to poly-L-lysine and carboxymethyl-cellulose) and one dose of human diploid rabies vaccine. This combination proved to be as effective as hyperimmune serum and vaccine, and much better than vaccine alone. The combination of the interferon inducer plus vaccine could be administered at least up to 48 hours after the very severe challenge given and still provide marked protection.

Animals↗
PubMed1978

Topical treatment of vaccinia virus infection with an interferon inducer in rabbits.

Ointment containing 1.7 mg/g of the interferon inducer poly (ICLC) (a complex of polyriboinosinic-polyribocytidylic acid and with poly-L-lysine and carboxymethylcellulose) was effective both prophylactically and therapeutically against vaccinia virus infection in rabbit skin. Poly (ICLC)-treated animals developed higher titers of local interferon and of circulating virus-neutralizing antibodies than placebo-treated animals. Serum levels of greater than 100 units of interferon/ml were found 24 hr after application of the poly (ICLC) ointment to the skin of uninfected rabbits.

Administration, Topical↗
PubMed1978

Phase I-II trials of poly IC stabilized with poly-L-lysine.

Poly IC, stabilized with poly-L-lysine and carboxymethyl cellulose (poly ICLC), resists hydrolysis by primate serum (unlike the parent compound), induces high levels of serum interferon, and is effective in acute viral infections of subhuman primates. In a phase I-II clinical trial, poly ICLC was given iv in 15 daily doses of 0.5-27.0 mg/m2 to 19 patients with various solid tumors and to six patients with acute leukemia (1-65 years of age). At least three complete trials were conducted at each of six dose levels. Toxic reactions included fever (in 100% of trials), nausea (44%) hypotension (28%), thrombocytopenia and leukopenia (68%), erythema (12%), and polyarthralgia plus myalgia (16%). Hypotension and arthralgia-myalgia were related to dose level and/or magnitude of interferon induction, but other toxic manifestations were not. Poly ICLC induced significant serum interferon levels in 76% of trials, and the correlation between dose and peak interferon titer was linear. The maximum tolerated dose for all patients at a given drug dose was 12 mg/m2; at this dose, the mean peak interferon titer was 1940 reference units/ml. At a dose of 18 mg/m2, the mean peak interferon titer was 4473 reference units/ml, but severe myalgia and arthralgia were intolerable in at least half of the patients, and most had significant hypotension. At a dose of 27 mg/m2, one patient had acute renal failure. At high doses, iv poly ICLC also induced interferon in the cerebrospinal fluid.

Adolescent↗
PubMed1977

Swine influenza virus vaccine: potentiation of antibody responses in rhesus monkeys.

Polyriboinosinic-polyribocytidylic acid stabilized with poly-L-lysine and carboxymethylcellulose [poly(ICLC)] enhances the antibody response in rhesus monkeys immunized with swine influenza virus subunit vaccine. Monkeys given the vaccine-adjuvant combination had earlier and significantly (P less than .05) higher titers by 14 days compared to those that received vaccine alone. The potentiation of the antibody response of young monkeys given a split-virus vaccine in combination with poly(ICLC) suggests that this vaccine-adjuvant combination may similarly provide a potentially useful alternative approach to the immunization of pediatric and young adult age groups against swine influenza.

Adjuvants, Immunologic↗
PubMed1977

Effect of a nuclease-resistant derivative of polyriboinosinic-polyribocytidylic acid complex on yellow fever in rhesus monkeys (Macaca mulatta).

Rhesus monkeys (Macaca mulatta) treated with a newly developed nuclease-resistant complex of polyriboinosinic-polyribocytidylic acid, poly-L-lysine, and carboxymethylcellulose [poly (ICLC)] did not die after challenge with virulent Asibi strain yellow fever (YF) virus. The strain of virus is sensitive to the effects of interferon in vitro and is lethal for rhesus monkeys four to six days after subcutaneous administration of 1,000 plaque-forming units of the virus. The mortality rate was reduced in monkeys initially treated 8 hr before or after inoculation of virus but was unchanged in monkeys initially treated 24 hr after challenge. Treated monkeys developed neutralizing antibody to YF virus. The successful treatment of yellow fever in a primate model with use of poly (ICLC) suggests a meaningful role for the interferon system in the host defense against this viral infection.

Animals↗
PubMed1977

Successful prophylaxis against rabies in mice and Rhesus monkeys: the interferon system and vaccine.

Addition of interferon to ineffective rabies virus vaccines by the local injection of either exogenous interferon or a potent interferon inducer (a complex of polyriboinosinic-polyribocytidylic acid containing poly-L-lysine and carboxymethylcellulose) into the footpads of mice previously challenged with rabies virus dramatically reduced the mortality rate. A significant reduction in mortality rate was also noted when the interferon system was administered to rhesus monkeys, but only when treatment was given 6 hr after challenge with rabies virus. Since the monkeys were given an overwhelming challenge of virus, the treatment had to be given quickly to obtain results comparable to those in mice.

Animals↗
PubMed1977

Interferon induction in cynomolgus and rhesus monkey after repeated doses of a modified polyriboinosinic-polyribocytidylic acid complex.

Serum interferon activity was determined in 12 cynomolgus and 12 rhesus monkeys injected intravenously once daily for 10 days with from 0.1 to 6.0 mg of a stabilized polyriboinosinic acid . polyribocytidylic acid complex per kg, composed of polyriboinosinic acid . polyribocytidylic acid, poly-1-lysine, and carboxymethylcellulose [poly(ICLC)]. Interferon activity was detected 2 h after the first injection, with maximum activity occurring 8 h after the second injection. A period of hyporesponsiveness occurred after the third injection of poly(ICLC) in all monkeys and lasted until the sixth injection in the rhesus monkeys, when interferon activity again became more elevated. The delayed rebound was not as apparent in cynomolgus monkeys. Rhesus monkeys injected with 6 mg/kg did not exhibit serious side effects.

Animals↗
PubMed1977

Interferon induction by radioprotective mercaptoalkylamines and derived thiophosphates.

Radioprotective thiols (five mercaptoalkylamines and four derived thiophosphates) induced interferon and resistance to virus infection. Interferon production occurred in human and mouse nonlymphoid cell cultures. One of the thiols, S,2-aminoethylisothiourea, given intraperitoneally, protected mice against two unrelated viruses--Semliki forest virus and Herpesvirus hominis type 1. Two structurally different radioprotective thiols--the disulfide cystamine and L-cysteine--were unable to induce the firus resistance state or interferon.

Animals↗
PubMed1977

Effect of interferon on togavirus and arenavirus infections of animals.

The sensitivity of togaviruses to the effects of IF appears to permit successful exploitation of IF inducers, whereas the relative insensitivity of arenaviruses to IF in vitro appears to correlate with the complete lack of success of poly (ICLC) therapy in the monkey model. Noteworthy is the successful use of poly (ICLC) against fatal encephalitis caused by JE virus in monkeys. Additional studies appear to be warranted to characterize further the role of IF and/or IF inducers in other model infections prior to studies in man.

Animals↗