Intrathecal interferon in the treatment of multiple sclerosis. Patient follow-up.

Follow-up observations on patients with multiple sclerosis who were treated with human fibroblast interferon (interferon beta) administered intrathecally for six months revealed a persisting beneficial effect in terms of a reduction in exacerbation rates. At the time of our last report in 1982, ten interferon beta recipients had shown a reduction in their mean exacerbation rate from 1.8/yr before the study to 0.2/yr during the study while ten control patients with multiple sclerosis showed no change in their rates during the study (0.69/yr) compared with before it (0.68/yr). That report was based on observations made for means of 1.9 years in the recipients and 1.6 years in the controls. The recipient patients have now been followed up for 4.4 years (mean) and their exacerbation rates have continued to decrease to a current mean level of 0.16/yr. The control patients were "crossed over" and began receiving interferon beta intrathecally after they had been in the study for two years without showing any change in their rate. During the 2.0 years since crossover they also have shown a reduction in exacerbation rate to a mean of 0.30/yr. The toxic side effects of interferon beta administered intrathecally were acceptable in view of the benefit achieved. Interferon was identified in the cerebrospinal fluid (but not the serum) of two patients prior to treatment, which is probably a manifestation of de novo production of interferon by the central nervous system in response to the multiple sclerosis disease process.

Antiviral effects of recombinant human tumor necrosis factor.

The antiviral action of recombinant human tumor necrosis factor (TNF) was studied using assay systems to determine inhibition of viral cytopathic effect (CPE), as well as suppression of virus growth measured by plaque assays. TNF was cloned and prepared by Asahi Chemical Industry, Japan. Antiviral activity against human herpes simplex virus (HSV) types 1 and 2, cytomegalovirus (CMV), varicella-zoster virus (VZ), vesicular stomatitis virus (VSV) and encephalomyocarditis virus (EMC), was demonstrated in human diploid fibroblasts following pretreatment with TNF overnight. The antiviral action was completely neutralized by anti-interferon (IFN)-beta serum, but not by anti-IFN-alpha or -gamma antibodies. This suggested the induction of IFN-beta by TNF. The antiviral action was synergistically enhanced by human IFN-gamma. Several non-human cell lines were tested but 10 of 11 failed to be protected from VSV- and/or EMC-induced CPE following pretreatment by TNF. The anticellular effects of TNF were tested in human and in non-human tumor cell lines. The results indicate that the susceptibility of cells to the two activities of TNF, antiviral and anticellular, was distinct, and that antiviral activity of TNF is more species-specific than its anticellular action.

Quantitative study of endocrine cells immunoreactive for calcitonin in the normal adult human lung.

There was no significant variation in the numbers of bronchopulmonary endocrine cells immunoreactive for calcitonin in five pairs of adult human lungs either from case to case or between groups of anatomically equivalent lobes. This was the case whether their numbers were expressed in relation to epithelial length or to the total number of epithelial cells. The mean (SD) values for the frequency of occurrence of these cells in all 25 lobes studied were 4.3 (1.9) per 10 cm of epithelial length or 1.70 (0.78) per 10 000 epithelial cells. Most immunoreactive cells were single and situated in the airways; only three neuroepithelial bodies were observed, and no cells were present in the parenchyma examined. This study provides further evidence that the functional character of these cells may not be confined to early life.

Poly ICLC induces anti-IC antibodies in mice and rabbits.

Poly ICLC is an interferon (IFN) inducer and antiviral, antitumor, radioprotective, and immunoregulatory agent. We show that administration of poly ICLC to mice and rabbits also results in the presence of anti-IC antibodies in their serum.

Medication bezoar: intestinal obstruction by an isocal bezoar. Case report and review of the literature.

Medications may occasionally obstruct the gastrointestinal tract by virtue of their physical mass. Obturative obstruction of the alimentary tract is reportedly caused by an increasing number of medications, including hydroscopic bulk laxatives, cholestyramine, nonabsorbable antacids, and vitamin C tablets. Inspissated Isocal tube feedings caused jejunal obstruction in a postoperative patient. Medication bezoars are a rare cause of intestinal obstruction that may result in significant patient morbidity, including bowel necrosis, perforation, and peritonitis. The radiographic appearance may mimic an abdominal abscess.

Physico-chemical characterization and partial purification of mouse immune interferon.

Mouse immune (type T) interferon was produced from suspensions of spleen cells (1 X 10(7) cells/ml) treated with 3 micrograms/ml of phytohaemagglutinin. The crude interferon was chromatographed on four sorbents with varying affinities, namely concanavalin A-Sepharose, Affi-Gel 202, Blue Sepharose CL-6B and Phenyl-Sepharose CL-4B. With each of these the interferon activity was observed to have considerable heterogeneity. By means of affinity chromatography, mouse immune interferon was purified 100 to 200 times with concomitant complete recovery of activity.

Prevention of varicella zoster (VZ) with poly(I) . poly(C) given during the incubation period.

Poly I . Poly C (Poly I:C) was administered to six children with cancer who were exposed to varicella zoster (VZ) and who were under active treatment to determine if this agent could prevent the development of overt varicella zoster (chickenpox). Poly I:C was administered as a single injection during the incubation period, but beyond 72 hours, since zoster immunoglobulin (ZIG) is a proven effective agent in the first 72 hours. None of these patients had a prior history of VZ and neither ZIG nor any other known antiviral agent was administered to these patients. None of the children developed chickenpox. This appears significant but awaits confirmation in a larger control study.

Identification of the T cell subset that produces human gamma interferon.

Positive and negative selection procedures combined with cytofluorographic analysis and lysis with monoclonal antibodies were utilized to identify the T lymphocyte subset that produces human gamma interferon (gamma-IFN) (formerly referred to as "immune" or "type II" interferon) in response to mitogen stimulation. Lymphocytes were separated on the basis of their Fc receptors for IgG or IgM, their nonreactivity with IgM or IgG antibodies, and their reactivity with the monoclonal antibodies OKT4, OKT8, OKT11a, and OKM1. Isolated T cell subsets were incubated with the gamma-IFN inducer, phytohemagglutinin. Three days after induction, the cell supernatants were harvested and assayed for interferon. The T cell subset that produces gamma-IFN was identified as E rosette positive with the phenotype: T gamma, T non-micro, OKM1+, OKT4-, OKT8- and OKT11a+. gamma-IFN production by cells was resistant to doses of x-irradiation that abrogate mitogen-induced T suppressor function but was highly sensitive to low doses of 4-hydroperoxycyclophosphamide. These data demonstrate that gamma-IFN is produced by the T gamma, OKM1+ lymphocyte subset, but these cells may also require the presence of accessory monocytes for elaboration of gamma-IFN. The anti-proliferative activity of gamma-IFN may be responsible for the previously described suppressor function of this subset, and gamma-IFN production by T gamma cells may distinguish this subset from the suppressor/cytotoxic functions of the OKT8+ subset or the mitogen-induced OKT4+ suppressor.

Antiviral and antiproliferative properties of liposome-associated human interferon-gamma.

Recombinant human interferon-gamma (rHuIFN-gamma) was associated with liposomes in an attempt to improve its therapeutic efficiency. It was associated with liposomes composed of phosphatidylserine (PS) and phosphatidylcholine (PC) at a ratio of 3:7, and of PS:PC and cholesterol (CHOL) at a ratio of 1:4:5 with efficiencies of 13% and 21%, respectively. The lipid composition influenced the antiviral activity of the liposome-complexed IFN-gamma tested against vesicular stomatitis virus. IFN associated with PS:PC liposomes was fully bioavailable and degraded by trypsin treatment. In contrast, PS:PC:CHOL-IFN was resistant to trypsin, and appeared latent as its full biological activity was seen only after disruption of the liposomes with detergent. Four human tumor cell lines were exposed to free and liposome-associated IFN-gamma. The growth of three solid tumor lines (colon, bladder, and lung) was inhibited by similar concentrations of free IFN and PS:PC-IFN. In contrast, less PS:PC-IFN than free IFN was needed to inhibit histiocytic lymphoma cells. Higher concentrations of PS:PC:CHOL-IFN than of free IFN were needed to inhibit growth of all four cell lines. The specificity of these effects of liposome-associated IFN-gamma were shown by their partial or complete neutralization by antibody to IFN-gamma. When liposome-IFN complexes of either type were stored at 4 degrees C, 30% of the IFN activity remained after 7 days; thereafter, decay was minimal over the next 3 weeks. These data show the formation of stable HuIFN-gamma-liposomes and indicate that the lipid components of these complexes influence their antiviral and antiproliferative activity for several different cell types.

Glycosylation of interferons. Effects of tunicamycin on human immune interferon.

Human immune interferon, induced in leukocytes by phytohemagglutinin, was prepared in the absence and presence of tunicamycin, an antibiotic which selectively inhibits the glycosylation of newly synthesized glycoproteins. Interferon preparations, produced in the absence of the antibiotic, displayed a considerable chromatographic heterogeneity on: (a) concanavalin A-agarose, (b) phenyl-agarose, (c) Cibacron Blue F3GA-agarose, and (d) polyuridylic acid-agarose. This heterogeneity was completely eliminated when tunicamycin (2 microgram/ml) was present during induction of interferon; all activity was then recovered in the breakthrough fractions from all sorbents. The level of interferon activity in leukocyte culture fluid was not affected by tunicamycin within the range of concentration 0.05 to 2.0 microgram/ml. These data indicate that (a) human immune interferon undergoes glycosylation, and tunicamycin is an effective inhibitor of this process. Thus, it appears that (b) at least some of the carbohydrates of human immune interferon are N-glycosidically linked. Moreover, it seems that (c) glycosylation is not necessary for an interferon molecule to either be secreted by the cell or (d) to express its antiviral function. Such properties of human immune interferon as (e) the apparent hydrophobicity and (f) an affinity for a polyribonucleotide are conferred only when its glycosylation is unimpaired.

Molecular structure of human fibroblast and leukocyte interferons: probe by lectin and hydrophobic chromatography.

Structural differences between human leukocyte virus-induced interferon and human fibroblast polyinosinic-polycytidylic acid (rIn-rCn)-induced interferon have been noted in previous studies. This study reports the behavior of human leukocyte and fibroblast interferon, induced by virus and by rIn-rCn, in several lectin and hydrophobic chromatographic systems. Differences in both glycosylation and in hydrophobicity of human leukocyte and fibroblast interferons are documented. Human fibroblast interferon is a glycoprotein, whereas our evidence suggests that human leukocyte interferon probably is not. Also, fibroblast interferon is more hydrophobic than leukocyte interferon, as probed on several hydrophobic adsorbents. The possible relationships of these differences to each other and to antigenic variations are discussed. Generally, the differences appear to be attributable to the cell type in which the interferon was induced. However, our results suggest that at least subtle differences in the processing of the induction signal (virus or rIn-rCn) within the same cell type may occur, slightly altering some structural features.

Interferon production and lymphocyte transformation in lymphocytes of leukemic patients.

The high incidence of viral infections in patients with lymphocytic leukemia is well documented, but the role played by interferon in the pathogenesis of such infections is not known. In this study, we investigated the possibility that gamma (gamma) interferon production, induced by phytohemagglutinin (PHA) might be impaired in leukocytes from patients with acute lymphocytic leukemia (ALL). We also compared this response with alpha (alpha) interferon production, and with PHA-stimulated lymphocyte transformation. We have shown that the gamma interferon response of leukocytes from patients, both in relapse and in remission, was markedly lower than in leukocytes from normal donors. However, the alpha interferon response in leukocytes from the patients was normal. In contrast the defective gamma interferon response to PHA stimulation of cells from patients in remission, lymphocyte transformation by PHA was normal. Lymphocytes from patients in relapse has a delayed response. Our findings suggest (1) that the defective gamma interferon response which occurs in cells from patients with ALL, both in relapse and remission, contributes to increased susceptibility to viral infections, (2) that alpha interferon may not be the optimal type of interferon for treatment of certain viral infections, and (3) that different triggering mechanisms, or different receptors, exist for PHA-induced gamma interferon production and for lymphocyte transformation in cells of patients with ALL.

Nature of the molecular heterogeneity of human leukocyte interferon.

The existence of two components of human leukocyte interferon has been recently reported. In the present study, the nature of this molecular heterogeneity was explored by affinity chromatography on immobilized micro- and macroligands, ion-exchange chromatography, and molecular sieving. Chromatography on a series of alkyl-agarose adsorbents shows, for the first time, the intrinsic hydrophobicity of human leukocyte interferon. Additionally, the separation of two interferon components is achieved by use of the alkyl-agarose as well as by the omega-aminoalkyl-agarose adsorbents. Clear-cut separation of the two components was also achieved by chromatography on BSA-CH-Sepharose and on DEAE-Bio Gel A. An important feature of these separations is that they do not require the use of denaturing conditions. The molecular weights of the leukocyte interferon components, as determined on Sephadex G-75, are quite similar or identical, approximately 26,000. Thus, the molecular heterogeneity of human leukocyte interferon can be attributed, at least in part, to differences in the hydrophobicity and ionic properties of its two components.