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Biomedical subjects

K Paucker

Publications and source records attributed to K Paucker.

At least 19 recordsLinked to original sources
PubMed1982

Presence of interferon during bacterial otitis media.

To examine the possibility that interferon (IFN) production plays a role in otitis media, specimens of middle ear fluid (MEF) were cultured for bacteria and viruses and assayed for IFN. Twenty (33%) of 81 MEF specimens from children attending a pediatric clinic contained 50-600 units of IFN/ml. Characterization of high-titered samples by cell species specificity, stability at pH 2, nonspecificity for virus, and cell-bound antiviral activity showed the major properties of IFN. With or without the addition of antibody to IFN to 88 specimens of MEF before viral culture, viruses were recovered from only four specimens (5%) whereas bacteria were isolated from 62 specimens (70%). IFN was present in most MEF specimens from which bacteria were isolated. Among the MEF specimens that contained bacteria and IFN, there was no association with a particular bacterial species.

Adenoviruses, Human↗
PubMed1981

Affinity chromatography of primary human amnion interferon.

The chromatographic behavior of human amniotic interferon on various affinity chromatography ligands was studied. Most of this interferon bound strongly to bovine plasma albumin-agarose, cibacron blue F3GA-agarose, concanavalin A-agarose and L-tryptophyl-L-tyrosine-omega-carboxyl-pentyl-agarose. After binding most of the interferon activity was eluted only with 50 percent ethylene glycol, showing the high hydrophobicity of this interferon. Smaller quantities could be recovered after phosphate-buffered saline elution or with increased salt concentration. On BPA-omega-carboxy-pentyl-agarose and omega-amino-hexyl-agarose, the majority of the biological activity was found in the break-through fraction (eluted with phosphate buffered saline) while some interferon was displaced with high salt or ethylene glycol. Increasing the salt concentration and lowering the pH was necessary to elute interferon from zinc chelate-agarose. These patterns indicate that human amniotic interferon is similar to human fibroblast (beta) interferon but different from human leukocyte (alpha) interferon. However, the heterogeneity displayed by amniotic interferon on bovine plasma albumin-agarose requires further investigation.

Amnion↗
PubMed1981

Antigenic cross-reaction between the alpha types of human and mouse interferon.

Cross-neutralization of the alpha and beta types of human and mouse interferons was tested using antibodies directed against the heterologous types of interferons. The alpha type of mouse interferon (MuIFN-alpha) prepared from L cells was found to be completely neutralizable by high-titered antibody against human alpha-type interferon (HuIFN-alpha), although the titers were much lower than those obtained in neutralization reactions with the homologous interferon. MuIFN-alpha from virus-induced lymphocytes, as well as non-glycosylated MuIFN-alpha from L cells, reacted similarly. The cross-reaction was also observed by the binding of anti-HuIFN-alpha antibody to a column of immobilized MuIFN-alpha. The binding experiment indicated that only a small fraction of the anti-HuIFN-alpha antibody population is heterologous reactive. Reciprocally, HuIFN-alpha from L cells, again with relatively low antibody titers, and the antibody responsible for the heterologous reaction was shown to be the anti-MuIFN-alpha and not anti-MuIFN-beta type. It is concluded that the alpha types of human and mouse interferon bear an antigenic homology. On the other hand, no significant antigenic cross-reactivity has been detected between the beta types of human and mouse interferons.

Animals↗
PubMed1981

Immune reactions and long-term therapy with human leukocyte interferon.

Twenty patients with osteosarcoma were treated with exogenous human leukocyte interferon for periods ranging from 6 to 18 months. Eleven of them remained free from detectable tumour growth during this treatment. Blood samples from all patients were tested for antibodies against interferon and against impurities in the interferon preparations. No patient developed detectable levels of neutralizing antibodies against interferon. All patients formed antibodies against contaminants in the concentrated crude interferon and the partially purified interferon preparation which had been used for treatment.

Adolescent↗
PubMed1980

Lymphocyte blastogenesis and interferon production in adult human leukocyte cultures stimulated with cytomegalovirus antigens.

Lymphocyte blastogenesis and interferon production were measured in adult human leukocyte cultures stimulated with purified or crude cytomegalovirus antigens. Leukocytes from seropositive adults underwent blastogenesis when stimulated with purified or crude Towne strain antigen, whereas neither antigen stimulated blastogenesis in cultures from seronegative donors. The concentrations of antigens yielding maximal blastogenesis varied among the individuals tested. When cultures from seropositive individuals were stimulated with antigens prepared from three different CMV strains--AD-169, Towne, and Davis--comparable levels of blastogenesis were detected. Type 1 interferon was detected in supernatants of cultures stimulated with crude antigens regardless of the immune status of the donor. In contrast, when purified antigen was used as the stimulant, only cultures obtained from seropositive individuals produced detectable levels of interferon, which appeared to be predominantly type 2 or immune interferon.

Antigens, Viral↗
PubMed1979

Impaired cellular immunity to cytomegalovirus in congenitally infected children and their mothers.

Cell-mediated immunity to cytomegalovirus (CMV) was determined in congenitally infected children and their mothers by use of assays for CMV-specific lymphocyte blastogenesis and interferon production. Six viruric children responded poorly in both assays. Two older nonviruric children responded in the blastogenesis assay, and lymphocytes from one of them produced interferon. Mothers of older children usually responded in the blastogenesis assay, but only one of them produced interferon. Mothers whose infected infants were younger than nine months of age responded poorly in both assays, while control seropositive postpartum women generally responded normally. The cell-mediated immune defects detected in this study may play a role in the pathogenesis of congenital CMV infection.

Cytomegalovirus↗
PubMed1979

Molecular species of interferon induced in mouse L cells by Newcastle disease virus and polyriboinosinic-polyribocytidylic acid.

Interferons were stimulated in mouse L cells by Newcastle disease virus (NDV) or by polyriboinosinic-polyribocytidylic acid poly(rI).poly(rC). These were fractionated by sequential affinity chromatography on bovine plasma albumin (BPA)-Sepharose and on omega-carboxypentyl (CH)-Sepharose. Based on their interaction with CH-Sepharose, interferon induced by NDV was resolved into three major bands of activity (L/NDV-1,2,3) and poly(rI).poly(rC)-interferon into two (L/rI:rC-1,2). These interferon components were purified to a specific activity of 3 X 10(7) to 4 X 10(7) units/mg protein by antibody affinity chromatography and examined by electrophoresis in SDS-polyacrylamide gels. A total of five molecular species was thus identified for NDV-induced interferon and three for poly(rI).poly(rC) induced interferon, as summarized in Table 1. We conclude from our observations that mouse interferons can be produced by L cells in multiple forms with specific physiochemical properties and in proportions determined by the type of agent employed for induction.

Animals↗
PubMed1979

Antigenic properties of human lymphoblastoid interferons.

Most virus-induced human lymphoblastoid interferons examined contained variable proportions of the Le and F antigenic species described for human leukocyte interferon. The F species was not detectable in interferons liberated spontaneously from human lymphoblastoid cells in culture. Lymphoblastoid interferons differed considerably in their interaction with the same anti-interferon serum. Spontaneous interferons required approximately ten times less antibody for neutralization than interferon induced by virus in the same cultures or in Namalva cells. The findings suggest that either spontaneous interferons contain fewer inactive antibody-binding molecules than virus-induced lymphoblastoid interferons or the number and distribution of antibody-combining sites, and possibly other surface properties of the interferon molecule, may be influenced by the manner in which spontaneous and induced interferons egress from the cells.

Antigens↗
PubMed1978

Antigenic properties and heterospecific antiviral activities of human leukocyte interferon species.

Human interferon obtained in peripheral leukocytes was purified approximately 1000-fold by affinity chromatography on anti-leukocyte interferon globulins coupled to Sepharose 4B, and by filtration on SDS-Sephadex G-100. The interferon was subsequently resolved into two molecular species by adsorption chromatography on SDS-hydroxylapatite. The two species which were eluted at different phosphate molarities from hydroxylapatite, could also be distinguished on the basis of electric charge properties and they migrated at different rates in SDS-polyacrylamide gels. Crossneutralization tests with monospecific rabbit anti-leukocyte and anti-fibroblast interferon sera revealed that the two species possessed leukocyte interferon-specific antigenic determinants. Both were immunogenic in mice and they were neutralized to a comparable degree by antisera against either component. A variable degree of antiviral activity was expressed by both interferon components in bovine, porcine and murine cells. However, the two interferon species were equally active in this respect, and the protective effects exhibited in homologous and heterologous cell cultures were similarly susceptible to reduction by beta-mercapto-ethanol. We conclude that the two molecular species of human leukocyte interferon are biologically similar.

Animals↗
PubMed1978

Production of antibodies to human interferons in mice.

Neutralizing antibodies were raised in mice that had been inoculated repeatedly with moderate quantities of human leukocyte interferon highly purified by affinity chromatography on immobilized anti-interferon globulins. Interferon preparations of lesser purity sensitized the mice to subsequent inoculations of interferon and almost invariably caused death before anti-interferon titers developed. Antibody-purified interferon stabilized by sodium dodecyl sulfate was a superior antigen to interferon that had received mouse serum albumin as an additive. The amount of antibody could be augmented by experimental induction of ascites. The antibodies specifically neutralized leukocyte and lymphoblastoid interferons but not those interferons obtained cultures of human foreskin fibroblasts, embryonic kidney cells, and amnion cells.

Animals↗
PubMed1977

Biological properties of human leukocyte interferon components.

Human leukocyte interferon, purified approximately 1000-fold by affinity chromatography on immobilized anti-interferon globulins and SDS-Sephadex filtration, was resolved into one major and one minor component by adsorption chromatography on hydroxylapatite and electrophoresis in polyacrylamide gels. These components were indistinguishable in their capacity to protect bovine, porcine and murine cells, and the antiviral activities of both were equally susceptible to reduction by beta-mercaptoethanol. They were neutralized to the same degree of rabbit anti-leukocyte interferon but were not neutralized by rabbit antifibroblast interferon serum. Mice immunized with either component developed antibodies to both but failed to form antibodies against human fibroblast interferon. Our present evidence indicates that the two components posses at most only minor structural and antigenic dissimilarities.

Animals↗
PubMed1976

Purification and characterization of human leukocyte interferon components.

Human leukocyte interferon, prepurified either by acid ethanol extraction or by affinity chromatography with antibodies, was further purified by gel filtration in the presence of sodium dodecyl sulfate. Interferon was eluted from gel filtration columns as an apparently homogeneous entity with a molecular weight of 26,600, resulting in an up to 50-fold additional purification during a single step. The antiviral activity could be further resolved into two components by hydroxylapatite adsorption chromatography. The isolated components (A and B) were distinguishable by isoelectric focusing and polyacrylamide gel electrophoresis. The apparent molecular weights were 20,000 to 16,000 and 16,000, respectively. No differences were detected in their susceptibility toward reduction of disulfide bonds by beta-mercaptoethanol. Both could be obtained on a preparative scale with minimal losses in biological activity.

Binding Sites↗
PubMed1975

Multiple active sites on human interferons.

Human interferons stimulated in peripheral leukocytes and foreskin fibroblasts are active in cultures of human and rabbit cells. The dominant factors in leukocyte and fibroblast interferons responsible for antiviral activity in rabbit cells were shown to be antigenically distinct from each other as well as from rabbit interferon. In addition, leukocyte interferon contained also a minor component with antigenic determinants characteristic of fibroblast specificity, which could be isolated by affinity chromatography on Sepharose-bound antibodies directed against firboblast interferon. Neutralization tests with selected anti-interferon sera suggested that the antiviral activities of leukocyte and fibroblast interferons in human and rabbit cells were associated with single molecules. A model is proposed where molecules of human interferon contain multiple reactive sites each of which is capable of interaction with cells of a different species. The number and distribution of these determinant sites may vary with the source of the human interferon and account for the differential in antiviral protection expressed in homologous and phylogenetically unrelated host cells.

Animals↗