The human interferons

Use of recombinant bovine alpha 1 interferon in reducing respiratory disease induced by bovine herpesvirus type 1

Intranasal or intramuscular treatment of calves with recombinant bovine alpha 1 interferon before challenge with bovine herpesvirus type 1 and Pasteurella haemolytica reduced clinical signs, number of sick days, lung lesions, and weight loss. The effective dose was determined to be relatively broad within the range of 1 to 50 mg per animal. No adverse effects were observed even at high doses of interferon (50 mg per animal). Administration before virus infection was more effective than administration at the same time as virus infection. Although interferon administration had dramatic effects on the survival of animals, it did not have much effect on virus secretion in the upper respiratory tract. Therefore, the mechanism by which interferon reduces the susceptibility of animals to viral-bacterial synergy was postulated to be via its immunomodulatory effects.

Bovine interferon: its biology and application in veterinary medicine

Investigations of the production and potential use of bovine interferons against viral infections have occurred since the first descriptions of interferons in other systems. The recent advent of recombinant DNA-technology has facilitated such studies and furthered our knowledge about the bovine interferon system in general. This review gives an overview of the biology, antiviral and immunomodulatory activities of bovine interferons. Areas in which the interferons are now applied or have potential application in viral diseases in cattle are described. Finally, the value of studies of the bovine interferon system with respect to comparative interferon research is discussed.

Treatment with human recombinant leukocyte interferons inhibits in vitro invasive ability of human lung carcinoma cells

The effects of treatment of human lung carcinoma cell line A 549 with recombinant DNA-derived human leukocyte interferons A (rIFN-alpha A) or D (rIFN-alpha D), and human lymphoblastoid interferon (Wellferon) on in vitro cell invasion were investigated in a quantitative invasion assay using human amnion. The A 549 cells treated with IFN for one day were incubated on the denuded basement membrane of the amnion in the absence of IFN, and cells which penetrated the full thickness of the connective tissue barrier were measured after 4 days. A dose-dependent inhibition of cell invasion was produced by the recombinant IFNs. The one day treatment of cells with 2.4 X 10(3) to 1.8 X 10(4) units/ml of rIFN-alpha A resulted in a 60-80 per cent inhibition of invasiveness compared to untreated cells. After a one day exposure of cells to 2.2 X 10(4) units/ml of rIFN-alpha D, cell invasion was reduced by approximately 70 per cent; a concentration of 4.4 X 10(3) units/ml had no apparent effect. Similar treatment with lymphoblastoid IFN (6 X 10(4) units/ml) had no significant effect on cell invasion. Accompanying the one day exposure to rIFN-alpha A (1.8 X 10(4) units/ml) or rIFN-alpha D (2.2 X 10(4) units/ml), (2',5') oligo (A) synthetase activity was induced approximately 20-fold; a 4-fold induction of enzyme activity was found in cells exposed to lymphoblastoid IFN (6 X 10(4) units/ml). After exposure of A 549 cells to the three IFNs at these concentrations, no significant alteration of the ability of the cells to attach to the basement membrane was found. Moreover, none of the one day IFN treatment regimens were cytocidal, and cell proliferation ability was not affected. This model system may be useful for investigating anti-invasive activity of other IFN types and subtypes.

Effect of rat and beta-human interferons on hyperacute experimental allergic encephalomyelitis in rats

Human interferon-beta (human IFN-beta) and rat interferon (rat IFN) were evaluated on experimental allergic encephalomyelitis (EAE) in rats, a delayed cellular reaction resembling human multiple sclerosis (MS). Rat IFN was active by intravenous and intracerebroventricular routes. It decreased the severity of clinical symptoms of paralysis during the 22 days of the assay. Human IFN-beta, on the contrary, had no effect when similarly tested in this rat model. Cyclophosphamide delayed the onset of paralysis, but levamisole enhanced the severity of the EAE.

A species of human alpha interferon that lacks the ability to boost human natural killer activity

Most species of recombinant leukocyte interferons (IFN-alpha A, -alpha B, -alpha C, -alpha D, -alpha F, -alpha I, and -alpha K) were capable of boosting human natural killer (NK) activity after a 2-hr treatment of cells at a concentration of 1-80 units/ml. In contrast, recombinant human IFN-alpha J was found to be incapable of augmenting NK activity after exposure of cells for 2 hr to concentrations as high as 10,000 units/ml. This inability of IFN-alpha J to boost NK activity was not complete because, after exposure of cells to a high concentration of IFN-alpha J (10,000 units/ml) for 18 hr, boosting of cytolysis was observed. IFN-alpha J appeared to interact with receptors for IFN on NK cells since it was found to interfere with the boosting of NK activity by other species of IFN-alpha. In contrast to its deficient ability to augment NK activity, IFN-alpha J has potent antiviral and antiproliferative activities. Such extensive dissociation of these biological activities has not been observed previously with any other natural or recombinant IFN species. Thus, this IFN species may be useful for evaluating the relative importance of various biological activities on the therapeutic effects of IFN, for understanding structure-function relationships, and for determining the biochemical pathways related to the various biological effects of IFN.

Antiviral drugs 1983

A number of antiviral compounds are currently available, and several others are of great interest. Trifluridine, idoxuridine, and vidarabine are effective topically in herpes simplex virus keratoconjunctivitis infection. Vidarabine (and presumably acyclovir) is effective in herpes simplex virus encephalitis and in herpes zoster infections in the immunocompromised host. Acyclovir is effective topically, orally, and intravenously in primary herpes genitalis, and the oral and intravenous forms are effective in recurrent herpes genitalis as well. Amantadine and rimantadine are effective prophylactically and therapeutically in influenza A infections. Ribavirin and interferon, although not licensed, are of great interest. Ribavirin may be useful in respiratory syncytial virus infections, and interferon may be of benefit in common colds and related disorders.