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conformational changes in influenza virus haemagglutinin and its monomer detected by monoclonal antibodies.exposure of influenza virus haemagglutinin to ph 5 results in conformational changes occurring in the molecule which are accompanied by antigenic modifications. furthermore, isolated haemagglutinin (ha) at a concentration of 0.1 nm undergoes dissociation from the trimeric to a monomeric form when exposed to ph 5. whether present on intact virus or as the isolated monomer, each form of haemagglutinin from ph 5 exhibits similar alterations in antigenic characteristics. these forms of ha show modif ...19852414938
the influence of norakin on the reproduction of influenza a and b viruses.the action of the anticholinergic drug norakin (triperiden) on the reproduction of influenza virus a and b strains was studied. in cell culture, primary transcription of influenza a/fpv/weybridge and of influenza b/japan/73 is strongly inhibited by norakin (20 micrograms/ml). when present simultaneously, norakin and rimantadine exert an additive effect. rimantadine-resistant mutants of influenza a exhibit a definite, though limited, cross-resistance to norakin, and vice versa. the results indica ...19852415085
expression of h-2i region-restricted cytolytic activity by an lyt-2+ influenza virus-specific t lymphocyte clone.the expression of lyt-2 on t lymphocytes has been postulated to correlate closely with restriction by, or alloreactivity to, class i mhc gene products, whereas i region-restricted or alloreactive populations appear to be associated with lyt-1 and l3t4 expression. however, exceptions to this axiom among alloreactive t cells have been shown to exist. in this report we describe a clonal population of influenza virus-specific t lymphocytes that bears the lyt-2+, l3t4- phenotype. notably, this clone ...19852415581
the nucleoprotein as a possible major factor in determining host specificity of influenza h3n2 viruses.in an attempt to assess the importance of the nucleoprotein (np) in the determination of host specificity, a series of experiments was performed on influenza a viruses of the h3n2 subtype. we have examined rescue of mutants of a/fpv/rostock/34 with temperature-sensitive (ts) lesions in the nucleoprotein (np) gene by double infection of chick embryo cells with h3n2 strains isolated from different species. the ts mutants could be rescued by all avian h3n2 strains but not by any of the human h3n2 i ...19852416114
isolation and characterization of influenza c virus inhibitor in rat serum.two hemagglutination inhibitors for influenza c virus were isolated from pooled sera of normal rats by sequential chromatography on blue sepharose cl 6b, ultrogel aca 22, and deae-cellulose. the two inhibitors were identified as alpha 1-macroglobulin and murinoglobulin by comparison with the authentic samples. these inhibitors abolished the hemagglutination by influenza c virus strains but did not affect the hemagglutination by influenza a and b virus strains. hemagglutination inhibition activit ...19852416143
isolation and characterization of human t cell lines and clones reactive to rabies virus: antigen specificity and production of interferon-gamma.by using a preparation of inactivated rabies virus, the blood mononuclear cells from five rabies vaccine recipients were stimulated in vitro in the presence of interleukin 2. t cell lines that displayed significant proliferative responses to whole rabies virus and to preparations of rabies glycoprotein and nucleocapsid were obtained from all the individuals. other antigens, such as diphtheria and tetanus toxoids, influenza a virus, hepatitis b surface antigen, and serum albumin, failed to induce ...19862416820
practical considerations of the ability of monoclonal antibodies to detect antigenic differences between closely related variants.this report describes an investigation of the abilities of different immunoassays to detect differences in affinities between related antigens for particular monoclonal antibodies. nine different monoclonal antibodies were used and 6 strains of influenza virus represented closely related antigens. parameters defining assay sensitivity were estimated experimentally for each antibody in 4 different immunoassays. predicted failures of particular assays to detect differences in antigen affinities, b ...19852416849
the antiviral activity of tetrazole phosphonic acids and their analogues.5-(phosphonomethyl)-1h-tetrazole and a number of related tetrazoles have been prepared and their effects on the replication of herpes simplex viruses-1 and -2 have been investigated as well as their abilities to inhibit the dna polymerases induced by these viruses and the rna transcriptase activity of influenza virus a. contrary to an earlier report, 5-(phosphonomethyl)-1h-tetrazole was not an efficient inhibitor of the replication of hsv-1 and hsv-2 in tissue culture. analogues of 5-(phosphonom ...19852417198
loss of enzyme activity in a site-directed mutant of influenza neuraminidase compared to expressed wild-type protein.full-length double-stranded dna copies of the neuraminidase (na) gene of influenza virus a/tokyo/3/67 (n2) and a mutant generated in vitro by site-specific, oligonucleotide-directed mutagenesis with a substitution of leucine for tryptophan at position 178 were cloned into an sv40 late replacement expression vector. indirect immunofluorescence of cells infected with these recombinant vectors showed the presence of na protein in the cytoplasm and on the surface of infected cells. cells expressing ...19862417413
clinical applications of antiviral agents for chemophrophylaxis and therapy of respiratory viral infections.table iii summarizes clinical applications of antiviral agents in respiratory viral infections. (table: see text) for influenza a virus infections, both oral amantadine and rimantadine are effective when used for seasonal prophylaxis and for prophylaxis in institutional populations. both of these drugs, as well as aerosolized ribavirin, have antiviral and therapeutic effects in uncomplicated influenza. it remains to be determined whether any of these modalities or possibly their combined use [44 ...19852417551
the anticholinergic anti-parkinson drug norakin selectively inhibits influenza virus replication. 19852417553
selection of influenza a virus adsorptive mutants by growth in the presence of a mixture of monoclonal antihemagglutinin antibodies.the influenza virus hemagglutinin contains four major regions that are recognized by antibodies able to neutralize viral infectivity. to investigate the effect of an antibody response directed against each of these sites on viral evolution, influenza virus a/pr/8/34 (h1n1) was grown in allantois-on-shell cultures in the presence of a mixture of monoclonal antihemagglutinin antibodies. this selection mixture contained antibodies (two or three antibodies per antigenic site) whose concentrations we ...19862418215
abnormalities of the in vitro cellular and humoral responses to tetanus and influenza antigens with concomitant numerical alterations in lymphocyte subsets in down syndrome (trisomy 21).peripheral blood leukocytes (pbl) from noninstitutionalized individuals with trisomy 21, paired with closely age-matched and/or family members as controls, were analyzed for different aspects of their cellular and humoral immune responses, and were phenotypically characterized by means of various monoclonal antibodies. both the in vitro pbl proliferative and antibody responses to a bacterial antigen (tetanus toxoid) and to viral antigens (influenza a/bangkok and b/singapore) were significantly d ...19862419411
arrest of daudi cell growth by inactive influenza virus in-vitro.we investigated the destructive capability of three influenza a strains, victoria, pr8, and their recombinant x47, against the human lymphoma cell line daudi. both victoria and x47 strains share the same envelope glycoproteins (h3n2), while pr8, the second parental strain of x47, differs in its envelope glycoproteins (hon1). the h3n2 strains and particularly the x47 recombinant were cytotoxic to daudi cells while the hon1 strain was not. to reduce the virulence of the oncolytic viruses, we inact ...19852419962
[isolation of the influenza virus from the tree sparrow and a study of the infectivity of this virus in wild birds of the central dnieper river area].an influenza virus belonging to the serovariant a/h3n2 and registered as a/sparrow/ukraine/83 was isolated from a member of synanthropic birds, a tree sparrow, near kanev. this virus showed low pathogenicity and immunologic activity in experimental infection of sparrows and other birds. sera from a number of avian and mammal species had antibodies to this virus which indicates that synanthropic and semi-synanthropic birds may be a connecting link in spread of influenza virus.19852420068
biological characteristics of a cold-adapted influenza a virus mutation residing on a polymerase gene.the biological function of a cold-adapted (ca) mutation residing on the pb2 gene of an influenza a/ann arbor/6/60 (a/aa/6/60) ca variant virus in the viral replication cycle at 25 degrees c was studied. the viral polypeptide synthesis of a/aa/6/60 ca variant at 25 degrees c was evident approximately 6 hours earlier than the wild type (wt) virus and yielded twice as many products. the quantitative analysis of viral complementary rna (crna), synthesized in the presence of cycloheximide, revealed t ...19862420313
in vitro biologic responses to native and surface-modified asbestos.a comparative study was made of in vitro biologic responses to native chrysotile, amosite, and crocidolite and corresponding asbestos fibers whose surfaces were modified by metal oxides. interferon induction by influenza virus was depressed by approximately 50% by all native asbestos whereas corresponding surface modified asbestos minimally affected this nonspecific cellular defense mechanism. the release of the cytoplasmic enzyme, lactate dehydrogenase (ldh), and lysosomal enzymes, beta-n-acety ...19862420583
conformational-dependent recognition of influenza virus hemagglutinin by murine t helper clones.a panel of h-2k class ii-restricted t helper (th) clones were established from individual cba mice intranasally infected with a/x31 influenza virus. in a study of their fine specificity, it was revealed that recognition of hemagglutinin (ha) by certain th clones was dependent on conformational features of the molecule. five ha-specific th clones failed to recognize x31 mutant viruses r19 and r20 each with a his to arg substitution at position 17 of ha1. this amino acid substitution affects the c ...19862420611
influence of antigen structure on the activation and induction of unresponsiveness in cloned human t lymphocytes.using cloned human helper t lymphocytes reactive with a 24 amino acid peptide (p20) of the carboxyl terminal of the ha-1 molecule of influenza haemagglutinin we have investigated the influence of antigen structure on the activation and in the induction of antigen specific unresponsiveness of t cells. for this analysis stereoisomers and structural isomers of p20 have been constructed. p20 in the form of a single loop created by a disulphide based between residue 306 and an additional cysteine at ...19862420700
peptide maps of t mutant of influenza virus.peptide maps were prepared by high-voltage electrophoresis and chromatography for t 30 degrees c mutant and the original strain a port chalmers 1/73 h3n2 of influenza virus. clear differences in the distribution and number of spots between the mutant and the original strain were found. the differences are due presumably to changes in the amino-acid sequences.19852421538
the influence of isoprinosine (iso) on some cell immunity parameters in mice infected with influenza viruses and in mixed viral-bacterial infections. i. the release of the migration inhibiting factor from spleen leukocytes.the influence of iso, the antiviral drug of immunomodulating activity, on the course of experimental influenza infections and mixed, viral-bacterial infections was studied. spleen leukocytes migration inhibition test, performed in vitro in the presence of specific antigens stimulating influence of the drug administered to the infected animals was observed.19852421684
an influenza a virus-specific and hla-drw8-restricted t cell clone cross-reacting with a transcomplementation product of the hla-dr2 and dr4 haplotypes.the clone ta10 is a t3+ t4+ t8- proliferative and cytolytic human t cell clone. this clone has been shown to be specific for the hemagglutinin of influenza a texas virus and restricted by an hla class ii molecule associated with the drw8-dw8.1 phenotype. here we show that ta10 and all of its subclones can also react with eight hla-drw8 negative, epstein-barr virus (ebv)-transformed cell lines or phytohemagglutinin blasts in the absence of influenza antigens. all of these cell lines are hla-dr2/d ...19862422266
protection of mice from lethal influenza: evidence that defective interfering virus modulates the immune response and not virus multiplication.intranasal administration of defective interfering (di) influenza virus (a/wsn) ensured the survival of 80% of c3h mice otherwise lethally infected with wsn by the intranasal route, whereas a control group which received beta-propiolactone-inactivated di virus in place of di virus died at 7.4 days post-infection. di virus-treated mice developed significantly less lung consolidation than controls although qualitatively the cellular pathology in the two groups was indistinguishable. surprisingly, ...19862422317
[the nature of amino acid substitution in antigenic drift of hemagglutinin n3 and neuraminidase n2 from the influenza virus].the nature of amino acid replacements in 16 drift variants of hemagglutinin h3 subtype and 5 drift variants of neuraminidase n2 subtype of the influenza a virus were studied. the dependences of relative replacement frequencies and relative quantities of frequent replacements upon differences of properties of substituted residues are plotted. in contrast to most of the known proteins, amino acid replacements in hemagglutinin and neuraminidase depend weakly on the physico-chemical parameters of am ...19862422540
analysis of antigenic determinants on internal and external proteins of influenza virus and identification of antigenic subpopulations of virions in recent field isolates using monoclonal antibodies and immunogold labelling.an electron microscopic immunogold labelling technique employing monoclonal antibodies has been applied to the antigenic analysis of influenza a and b viruses. reassortant influenza a h3n2 viruses containing haemagglutinin molecules from viruses isolated between 1968 and 1982 were analysed with a panel of monoclonal antibodies raised against viruses which appeared over the same period. the immunogold labelling technique clearly demonstrated the antigenic drift in the haemagglutinin molecule that ...19862423056
rapid rna sequencing using double-stranded template dna, sp6 polymerase, and 3'-deoxynucleotide triphosphates.a simple and efficient nucleic acid sequencing method is described in which rna transcription by the sp6 polymerase is specifically terminated using 3'-deoxynucleotide triphosphates. initial difficulties in resolving the rna ladder were overcome by replacing guanosine triphosphate by inosine triphosphate in the reaction mixture and electrophoresing gels at high temperature (50 degrees c). this method presents advantages over current sequencing techniques: unprocessed plasmid dna is the template ...19862423310
extensive diversity in the recognition of influenza virus hemagglutinin by murine t helper clones.a panel of h-2k class ii-restricted th clones were established from individual cba mice primed by infection with x31 influenza virus. 27 clones, which showed specific recognition of the ha surface glycoprotein, were all h3n2 subtype specific, in contrast to a t cell line which was crossreactive and which may have other specificities. 20 distinct ha-specific clones recognized a tryptic cleavage fragment of x31 consisting of residue 28-328 of ha1 (tops) which includes all the ab-combining regions ...19862423631
antigenic mapping of an avian h1 influenza virus haemagglutinin and interrelationships of h1 viruses from humans, pigs and birds.monoclonal antibodies to the haemagglutinin (ha) of the avian h1 influenza virus a/duck/alberta/35/76 were used to construct an operational antigenic map of the ha molecule and to study the interrelationships of h1 viruses from different hosts. haemagglutination inhibition tests between the monoclonal antibodies and variants selected by them provided evidence of four antigenic regions which overlap to varying degrees. avian h1 influenza viruses displayed a spectrum of reactivities to the monoclo ...19862423640
[structural rearrangements in influenza virus hemagglutinin during crossing the inter-species barrier]. 19862424700
functional definition of hla-dr and -dq epitopes specific for dr2-short, dwfjo haplotype.t-lymphocyte clones specific for the influenza a/texas virus were obtained by limiting dilution of activated t cells from an hla a2/3,b7/39,cw -/-,dr2-short/2 short,dqw1,dwfjo/fjo donor. among the proliferating clones studied, and irrespective of their antigenic specificities, most of them were restricted by epitope(s) on hla-dr molecules present only on dr2-short/dwfjo cells but not on dr2-negative or dr2-long positive (dw2,dw12,dw-) cells. two clones were restricted by epitopes borne by dq pro ...19862424833
fine specificity and antigen receptor expression among influenza virus-specific cytolytic t lymphocyte clones.influenza virus stimulates a vigorous cytolytic t lymphocyte (ctl) response in the mouse that is directed to several virion polypeptides. this report examines the fine specificity of a panel of murine influenza-specific ctl clones restricted by mhc class i products of the h-2d haplotype. ten of 22 a/japan/305/57-specific ctl clones analyzed were directed to the a/japan/305/57 hemagglutinin protein as detected by using target cells infected with a recombinant vaccinia virus containing hemagglutin ...19862424996
[radioimmunological analysis of viral antigens on a flat adsorbent of polyethylene film]. 19862425137
[use of monospecific antibodies for determining the antigenic determinant composition in the hemagglutinins of the h3n2 influenza viruses of 1979-1983].the study of the antigenic composition of hemagglutinins of influenza h3n2 viruses isolated during epidemic outbreaks in 1979-1983, carried out by means of monospecific antibodies to individual antigenic determinants, showed heterogeneity of the antigenic structure of epidemically active variants. some variants were antigenically identical to a/bangkok/1/79 virus. hemagglutinin structure of a/shanghai/31/80, a/philippines/2/82 and the like was found to contain a qualitatively new antigenic deter ...19862425492
[antigenic markers of the hemagglutinins of the influenza a and b viruses in the process of variability and the rapid diagnosis of influenza]. 19862425495
[antigenic drift of influenza a1 virus]. 19852425981
influenza nucleoprotein-specific cytotoxic t-cell clones are protective in vivo.influenza nucleoprotein (np) serves as a target antigen on abortively infected cells for cytotoxic t cells (tc) cross-reactive for all type a influenza viruses, and it can also prime mice for such tc. it is important to test the protective ability of np-specific tc clones in vivo in a productive influenza infection. in this report, we show that tc clones of this antigenic specificity protect mice against a lethal influenza infection on transfer to syngeneic recipients, and also that they reduce ...19862426185
an antigen-binding assay to determine the specificity of monoclonal antibodies against influenza virus and mapping of epitopes.a simple antigen-binding assay is described for determining the specificity of monoclonal antibodies against a/victoria/3/75 influenza virus. monoclonal antibodies were bound to polyvinylchloride microtitre wells via protein a and anti-immunoglobulin serum. radiolabelled cell extracts were then added and allowed to adsorb to the antigen. the bound material was eluted and analyzed by polyacrylamide gel electrophoresis and autoradiography. the method can also be used to study competitive binding o ...19862426296
characterization of monoclonal antibodies specific for sequential influenza a/pr/8/34 virus variants.a panel of monoclonal antibodies specific for a corresponding panel of sequentially selected variants of influenza a/pr/8/34 virus has been established. although the monoclonal antibodies are paratypically distinct, idiotypic relatedness has been observed. two cross-reactive idiotypes have been defined that are associated with the 7183 and s107 vh gene families, respectively. three of the four monoclonal antibodies utilize the vk21 group of light chains, and three vh genes belong to the vh7183 f ...19862426361
influenza viral glycoproteins induced cell-mediated cytotoxicity by an interferon-independent mechanism.human natural killer (nk) cells exposed to the influenza surface antigen neuraminidase (na) show high cytotoxic activity, as evaluated using chromium-labeled k562 target cells in a standard overnight cytotoxicity assay. the role of interferon (ifn) in the stimulation of nk cells was examined by using three separate approaches. the use of appropriate antibodies to check ifn- and na-specific cell-mediated cytotoxicity (cmc) stimulation showed that antibodies to ifn (-alpha, -gamma) did not alter n ...19862427216
structural and functional implications of a restricted antibody response to a defined antigenic region on the influenza virus hemagglutinin.a group of hybridoma antibodies that recognize structurally overlapping epitopes on the influenza virus hemagglutinin have been analyzed for the sequence of their immunoglobulin heavy and light chain variable regions. all vh regions derive from the same gene family, and only two vk genes, from different families, are involved. the repetitive and restricted use of these variable region genes indicates that considerable structural requirements influence the generation of antibodies specific for th ...19862427335
[dynamics of change in the antibacterial activity of mouse peritoneal cells during the development of experimental influenzal infection].the method of the radiometric determination of the antibacterial activity of peritoneal cells in the process of the development of viral infection has been approved. the genetically determined specific level of the antibacterial activity of these cells in different strains of mice has been established. the development of the lethal form of experimental influenza a in mice has been shown to be accompanied by the mobilization of nonspecific protective factors, including the system of interferons a ...19862428190
the molecular basis of antigenic variation in influenza virus. 19862428216
immunogenicity of loop-structured short synthetic peptides mimicking the antigenic site a of influenza virus hemagglutinin.in order to assess the relevance of conformation for the antigenic site a of the hemagglutinin of influenza virus we synthesized two peptides, comprising two variant sequences of the central part of site a (amino acids 140 - 146 of subunit ha1) inserted into an artificial peptide skeleton, which imposes a loop-like structure on the respective sequence stretch. assuming that the loop structure in the synthetic peptides would roughly approximate to the structure of the cognate protein sequence we ...19862428615
highly polymorphic products of both hla-dr and hla-dq genes contribute to the polymorphism of the hla-drw13 haplotype.we studied the polymorphisms of hla-dr and hla-dq products from hla-drw13 haplotypes by analyzing the restriction of influenza a-specific cloned t cells from an hla-drw13,dqw1,dw19 homozygous individual. the results show that some functional epitopes, which can be borne by either hla-dr or hla-dq molecules, are strictly correlated with the hla-dw19 subtype of hla-drw13. this clearly indicates that both hla-dr and hla-dq products contribute to the hla-dw19 subdivision of hla-drw13. at least two d ...19862428744
[immunological study of antigenic determinants in the isolated hemagglutinin of the influenza a virus (h1n1)].a preparation of isolated subunits of influenza a (h1n1) virus hemagglutinin was examined for antigenic properties by four serological tests: radioimmunoassay, radial immunodiffusion test, complement fixation test, and hemagglutination inhibition test with hyperimmune polyclonal serum to intact virion as well as with monospecific antibodies to individual antigenic determinants obtained by adsorption technique. in isolated hemagglutinin subunits, radioimmunoassay identified three main virus-speci ...19862429447
[genomic and antigenic analysis of strains of influenza a virus (h1n1) isolated in 1982-1983: approaches to the choice of the optimal vaccine strain].features of the genome and antigenic specificity of hemagglutinin of some influenza a (h1n1) virus strains circulating in the epidemic period of 1982-1983 were studied comparatively. analysis of the genome of the isolates under study in comparison with that of the reference a/england/333/80 strain and with each other has established changes not only in the genes coding for hemagglutinin and neuraminidase but also most of the genes coding for unglycolysed proteins. the antigenic specificity of he ...19862429448
[synergic therapeutic action of aprotinin and remantadine in experimental influenzal infection].chemotherapeutic treatment of influenza infection is possible with aprotinine, an inhibitor of proteinases blocking proteolytic shearing of virion hemagglutinin which is necessary for multicycle virus infection. the chemotherapeutic effect of antiinfluenza drug remantadine is due to inhibition of intracellular deproteinization of virions in the course of their penetration into cells. in mice infected with a highly lethal dose (about 400 mld50/animal) of influenza a/aichi/2/68 (h3n2) virus treatm ...19862429449
enhancement of histamine release from human basophils pretreated with different sialidases.histamine release from human basophils was investigated in vitro after removal of cell membrane sialic acid by three different sialidases. pretreatment of the cells with sialidases from cl. perfringens, v. cholera or influenza virus a2 enhanced histamine release induced by subsequent stimulation of the cells with anti-ige or the plant lectin concanavalin a and caused a shift to the left of the dose-response curve for anti-ige. the enhanced histamine release was reflected in a increased calcium s ...19862429528
laboratory characterization of influenza a viruses (h3n2)--pathogens of leningrad 1983 epidemic.seventy strains of influenza a virus (h3n2) isolated in leningrad during the influenza epidemic in january--march 1983 were studied. the virus isolates appeared to be markedly heterogeneous with respect to antigenic characteristics of surface glycoproteins, biological properties (haemagglutinating and neuraminidase activities, sensitivity to gamma-inhibitors, etc.) as well as genome structure. the identity of the virus isolates with the reference influenza a virus was as follows: 10% were simila ...19862429534
assembly of influenza hemagglutinin trimers and its role in intracellular transport.the hemagglutinin (ha) of influenza virus is a homotrimeric integral membrane glycoprotein. it is cotranslationally inserted into the endoplasmic reticulum as a precursor called ha0 and transported to the cell surface via the golgi complex. we have, in this study, investigated the kinetics and cellular location of the assembly reaction that results in ha0 trimerization. three independent criteria were used for determining the formation of quaternary structure: the appearance of an epitope recogn ...19862429970
hla b37 determines an influenza a virus nucleoprotein epitope recognized by cytotoxic t lymphocytes.human influenza a virus-specific, cytotoxic t cells have been shown previously to recognize the virus nucleoprotein on infected cells. ctl preparations from four hla b37-positive donors were shown to recognize a synthetic peptide that corresponded to amino acids 335-349 of the nucleoprotein sequence. influenza-specific ctl from 10 donors of other hla types failed to recognize this epitope. cd8+ ctl lines were derived from lymphocytes of two hla b37-positive donors and used to show that the pepti ...19862430041
[influenza a(h1n1) virus drift; alteration of the influenza vaccine for the 1986/'87 season]. 19862430197
synthesis of interferon in human leukocyte cells stimulated with influenza virus.strains of influenza a virus were tested for their ability to induce interferon synthesis in suspension of human leukocytes. both, active as well as uv-inactivated strains were shown to be weak interferon inducers as compared to newcastle virus. it appeared that interferon synthesis in human leukocytes was conditioned not by infectivity of the virus but by the presence of its surface antigens--hemagglutinin and neuraminidase.19862430545
influenza virus infection induces functional alterations in peripheral blood lymphocytes.this report describes alterations in functional responses to lectin-induced stimulation of peripheral blood lymphocytes and in the natural killer cell (nkc) activity, of college students, obtained during an outbreak of influenza a/philippines/2/82(h3n2) virus infection. these results are compared with similar observations in college students with an acute, febrile, noninfluenzal respiratory illness that occurred during the same outbreak. the lymphopenia typical of influenza during acute illness ...19862431043
influenza virus-induced encephalopathy in mice: interferon production and natural killer cell activity during acute infection.mice injected intracerebrally with infectious influenza virus (60 hemagglutinin units) developed lethargy, seizures, comas, and died 2 to 5 days postinfection. as early as 6 h after infection, the cerebrospinal fluid (csf) in these animals was infiltrated with polymorphonuclear cells, mononuclear leukocytes, and large granular lymphocytes. potent natural killer (nk) cell activity was observed for both csf and spleen cell populations over the same period. this nk cell activity correlated with int ...19862431159
[effect of influenza virus type a and interferon on various pathogenetic factors in bronchial asthma]. 19862431398
antigenic determinants of influenza virus hemagglutinin. xii. the epitopes of a synthetic peptide representing the c-terminus of ha1.a synthetic peptide comprising the c-terminal 24 amino acids of the heavy chain (ha1) of influenza virus hemagglutinin was constructed and examined for antigenic and immunogenic activity. monoclonal antibodies as well as polyclonal antisera raised against the synthetic peptide were able to bind to intact virus. this binding was greatly enhanced if the virus was first subjected to ph 5, suggesting that this treatment exposes the c-terminus of ha1. using synthetic analogs of the native sequence it ...19862431541
[the biological effects of coordination compounds of transitional metals. 6. effect of 4-methyl-2-aminopyridine-palladium chloride and cis-dichlorodiammine-platinum(ii) on retroviruses and the virus-associated rna polymerase of the influenza virus].the effect on retroviruses of two transition metal complexes of known antiviral activity, 4-methyl-2-amino-pyridine-palladium-chloride (map) and cis-dichloro-diammine-platinum(ii) (cis-ddp) has been investigated. the experiments included the evaluation of the action of compounds on virus particle-associated reverse transcriptase in exogenous assays, on virus propagation in persistently infected cell cultures and on virus infectivity in mice. in disrupted viruses and in the absence of excess prot ...19862431560
[molecular basis of the variability of epidemic strains of human influenza viruses].the data from literature and authors own studies are reviewed on variability of human influenza viral strains, isolated during the same epidemic season in different periods of pandemic cycle. the data obtained indicate that variability of epidemic strains of human influenza virus deals with the genes coding for outer membrane proteins (hemagglutinin and neuraminidase) as well as nonglycosylated proteins. circulation of a number of viral variants of the same serotype, differing in antigenic speci ...19852432423
characterization and in vivo distribution of influenza-virus-specific t-lymphocytes in the murine respiratory tract.cloned populations of antigen-specific, murine t-lymphocytes, maintained in long-term continuous culture, have been reported to exhibit functional activity upon adoptive transfer. few data are currently available on the in vivo distribution of these homogeneous, functional cell populations. such information is important to understanding the mechanisms by which t-lymphocytes exert their effector activity. we examined 2 cloned populations of influenza virus-specific t-lymphocytes. one clone was a ...19872432811
enhancement of host resistance against virus infections by mtp-pe, a synthetic lipophilic muramyl peptide--i. increased survival in mice and guinea pigs after single drug administration prior to infection, and the effect of mtp-pe on interferon levels in sera and lungs.muramyl tripeptide-phosphatidylethanolamine (mtp-pe, cgp 19835) displays prophylactic antiviral activity in mice infected with influenza viruses a and b, parainfluenza 1 virus or herpes simplex type 1 viruses (hsv/1) and in guinea pigs infected with herpes simplex type 2 viruses (hsv/2). mtp-pe is effective when given in a single intranasal dose as early as 1-4 weeks before infection. in the case of hsv/2 infections, prophylactic effectiveness can be demonstrated after a single topical applicati ...19862433236
monoclonal antibodies for characterizing h3n2 influenza viruses that persist in pigs in china. 19872433358
the lack of effect of inoculation with equine influenza vaccine on theophylline pharmacokinetics in the horse.several studies conducted during the past few years have shown that the pharmacokinetics of a variety of drugs may be altered following viral infection or vaccination. the elimination of drugs which are extensively metabolized, such as theophylline, may be prolonged, especially following exposure to rna viruses such as type a influenza or similar orthomyxoviruses. the purpose of this study was to determine whether vaccination of horses with equine influenza virus affected pharmacokinetic paramet ...19862433461
functional and antigenic domains of the matrix (m1) protein of influenza a virus.the membrane- and ribonucleocapsid (rnp)-binding domains of the matrix (m1) protein of influenza a virus (wsn strain) were partially mapped and characterized by reactivity with monoclonal antibodies (mab) as well as by proteolytic cleavages and amino acid sequencing of the resulting peptides. of two peptides formed by formic acid hydrolysis, a 9-kilodalton fragment at the amino-terminal third of the m1 protein was recognized by mab m2-1c6 (to epitope 1), and a 15-kilodalton fragment at the carbo ...19872433462
a single amino acid substitution in influenza hemagglutinin abrogates recognition by monoclonal antibody and a spectrum of subtype-specific l3t4+ t cell clones.a fine specificity analysis of influenza hemagglutinin-specific iak-restricted t cell clones using natural virus variants of the h3n2 subtype, monoclonal antibody-selected variants and a synthetic peptide corresponding to a variable region of the ha1 polypeptide has provided insight on the structural basis for t cell recognition. a glycine to arginine substitution at ha1 135 abrogates recognition by a panel of t cell clones which, according to their reactivity for natural virus variants, have di ...19872434337
analysis by plaque reduction neutralization assay of intertypic rotaviruses suggests that gene reassortment occurs in vivo.the sb-1a rotavirus recovered from a diarrheic piglet in the united states is a naturally occurring intertypic rotavirus. when studied by reciprocal neutralization tests, the sb-1a virus was similar, if not identical, to the porcine gottfried virus (serotype 4) and the porcine osu virus (serotype 5). analysis of reassortant viruses prepared from the sb-1a virus and the serotype 2 human ds-1 virus revealed that the antigenic specificity of the outer capsid protein vp3 of sb-1a was shared with the ...19872434522
high protection of animals lethally infected with influenza virus by aprotinin-rimantadine combination.the successful therapeutic synergism of aprotinin and rimantadine, which are known to attack different viral targets, was demonstrated in influenza-virus-infected animals. combined treatment with these drugs of mice infected with a highly lethal dose of mouse-adapted influenza virus prevented the development of fatal haemorrhagic pneumonia and protected about 75% of animals; whereas the separate administration of aprotinin and rimantadine induced 35% and 15% protection, respectively.19872434613
hemagglutination-inhibiting antibodies to equine influenza viruses in japanese horses and antigenic variation of the viruses. 19862435948
[comparative study of interferon inducers obtained from natural sources].interferon-inducing and antiviral effects of natural dsrna preparations of phage phi 6 and yeast cells were studied in the culture of murine cells l-929 and on random bred albino mice. both the preparations showed interferon inducing activity in the cell culture. however, for realization of their effect modification of the surface cell membrane by polycation exchange resin (deae-dextran) was required. the interferon-inducing activity of both of the natural dsrna in the mice was high. the maximum ...19872436574
modulation of t cells by cyclic amp in murine influenza virus infection. i. in vitro inhibition of cytotoxic t lymphocytes by exogenous cyclic amp analogues and by agents which increase intracellular cyclic amp concentrations.the effects of 8-bromo-cyclic amp and cyclic amp agonists (cholera toxin plus hydrocortisone and prostaglandin e2 plus 3-isobutyl-1-methylxanthine) on the cytotoxic activity of t cells generated during murine influenza virus infection have been examined. treatment of influenza a/wsn virus primed primary immune spleen cells and their cultured secondary effector t cells from balb/c mice with these agonists resulted in increases in cyclic amp levels. these agents also had a marked inhibitory effect ...19872437075
[study of the host glycosyl component of the influenza virus using monoclonal antibodies].the crossreacting glycosylated host component (cohc) of influenza virus propagated in chick embryo has been studied using the monoclonal antibodies (ma). the specificity of ma to cohc has been demonstrated by different methods. both ma of clones a9 and b7 react with the spatially overlapping antigenic sites of oligosaccharide chain, but only ma of b7 are active in hemagglutination inhibition test. the cohc is shown to be associated with both surface glycoprotein adsorbing on the surface of the v ...19872437446
cytotoxic t lymphocytes recognize a fragment of influenza virus matrix protein in association with hla-a2.both human and murine cytotoxic t cells (ctl) elicited in response to infection with influenza a viruses have been shown to be specific for internal viral proteins, such as the matrix and nucleoprotein. individual ctl epitopes have been identified in the nucleoprotein by successfully substituting short synthetic peptides for the intact virus in the preparation of target cells in cytotoxicity assays. the defined peptide epitopes have each been recognized by ctl in association with individual clas ...19872437457
[interferon and other immunological indices of influenza patients undergoing different methods of treatment].the authors review the results of immunological examinations of patients with influenza given adapromine and virazole drugs as well as reflex therapy aimed at increasing general host resistance. patients with influenza administered reflex therapy among other therapeutic measures developed more intensive increase of serum interferon activity in the acute period of the disease, with its more rapid decline; they had a high level of igm and more intensive rise of specific antibody (in the hi test) a ...19872437705
the influence of high temperature on human cells in culture, their sensitivity to viruses and their interferon-producing capacity.the influence of extremely high temperatures on the course of virus infection in vitro was studied. it has been shown that exposure of human cells (continuous cell line of embryonal skin-muscle tissue, donor blood leukocytes) to 43 degrees c leads to a significant increase in their sensitivity to cytopathic action of the viruses tested. noteworthy, the reproduction of these viruses under tested conditions did not differ from their reproduction in control cells. a dramatic inhibitory effect of hi ...19872437783
characterization of the equine influenza virus h3 with monoclonal antibodies.mouse monoclonal antibodies specific for the hemagglutinin of the prototype equine-2 virus, a/equine/miami/1/63 (h3, n8) demonstrated two related antigenic sites on the h3. one of the sites was detected on 14 h3 viruses isolated over a 22 year period (1963-1985). variant viruses were selected with these antibodies at frequencies similar to those described for h3 hemagglutinins from human isolates.19872437891
use of synthetic peptides of influenza nucleoprotein to define epitopes recognized by class i-restricted cytotoxic t lymphocytes.the conserved epitopes of influenza nucleoprotein (np) recognized by class i mhc-restricted ctl from cba (h-2k) and c57bl/10 (h-2b) mice have been defined in vitro with synthetic peptides 50-63 and 365-379, respectively. two db-restricted clones were described that recognize different epitopes on peptide 365-379. finally, the recognition of complete np was shown to be approximately 200-fold less efficient than peptide in the cytotoxicity assay. these phenomena are closely related to results with ...19872438367
intracellular localization of the viral polymerase proteins in cells infected with influenza virus and cells expressing pb1 protein from cloned cdna.the biosynthesis, nuclear transport, and formation of a complex among the influenza polymerase proteins were studied in influenza virus-infected mdbk cells by using monospecific antisera. to obtain these monospecific antisera, portions of cloned cdnas encoding the individual polymerase proteins (pb1, pb2, or pa) of a/wsn/33 influenza virus were expressed as fusion proteins in escherichia coli, and the purified fusion proteins were injected into rabbits. studies using indirect immunofluorescence ...19872438429
determination of the epitope 264 on the hemagglutinin molecule of influenza h1n1 virus by site-specific mutagenesis.full-length cdna of ha gene derived from b-1-23 virus, a variant of a/ussr/90/77 (a/ussr/77) (h1n1) which had been selected with monoclonal antibody (mab) 264 and contained an amino acid change at position 190 of the ha1 region, was cloned into the sv40 expression vector. hemabsorbing or fusion activities of the ha protein expressed on cv-1 cells infected with the recombinant virus were indistinguishable from those of the authentic ha protein on b-1-23 virus infected cells. the antigenicity of t ...19872440177
antigenic and genetic conservation of h3 influenza virus in wild ducks.the hemagglutinins of h3 influenza viruses isolated from migratory ducks on the pacific flyway in japan during the period 1977 to 1985 were analyzed antigenically and genetically. antigenic analysis using monoclonal antibodies to the hemagglutinins of a/aichi/2/68 (h3n2) and a/duck/hokkaido/8/80 (h3n8) viruses showed that antigenic drift occurred extensively in human strains, whereas the hemagglutinins of duck viruses were highly conserved. it was also found that the hemagglutinins of duck virus ...19872440178
[immunobiological analysis of isolated subunits of influenza virus hemagglutinin].the immunogenic properties of isolated subunits of influenza a/fm/1/47 (h1n1) virus hemagglutinin were studied. the antihemagglutinating serum was tested by the cft, hi, competitive solid-phase radioimmunoassay, and biological neutralization test. the antiserum was found to contain populations of antibodies to the three main antigenic determinants of hemagglutinin identical to the determinants of the intact virion, as well as antibodies to the antigenic components of host cells. the antiserum to ...19872440184
monoclonal antibodies detect m-protein epitopes on the surface of influenza virions.various data obtained with activable hydrophobic probes, proteolytic treatments and anti m-protein polyclonal antibodies strongly suggest that m-protein of influenza a is an integral part of the lipid bilayer of native virions and somehow spans at the surface of the virions. therefore we have looked for the presence of m-protein epitopes on the surface of influenza a virion by using four type a m-protein monoclonal antibodies. we developed a specific and sensitive competition elisa where intact ...19872440414
silicate minerals and the interferon system.natural-occurring minerals representative of six silicate classes were examined for their influence on interferon induction by influenza virus in rhesus monkey kidney (llc-mk2) cell monolayers. minerals within the classes nesosilicate, sorosilicate, cyclosilicate, and inosilicate exhibited either little or marked (50% or greater) inhibition of interferon induction. within the inosilicate class, however, minerals of the pyroxenoid group (wollastonite, pectolite, and rhodonite) all significantly s ...19872440670
the avian influenza virus nucleoprotein gene and a specific constellation of avian and human virus polymerase genes each specify attenuation of avian-human influenza a/pintail/79 reassortant viruses for monkeys.reassortant viruses which possessed the hemagglutinin and neuraminidase genes of wild-type human influenza a viruses and the remaining six rna segments (internal genes) of the avian a/pintail/alberta/119/79 (h4n6) virus were previously found to be attenuated in humans. to study the genetic basis of this attenuation, we isolated influenza a/pintail/79 x a/washington/897/80 reassortant viruses which contained human influenza virus h3n2 surface glycoprotein genes and various combinations of avian o ...19872441080
recognition of influenza virus proteins by cytotoxic t lymphocytes. 19872442273
mouse h-2k-restricted cytotoxic t cells recognize antigenic determinants in both the ha1 and ha2 subunits of the influenza a/pr/8/34 hemagglutinin.we have constructed two chimeric influenza hemagglutinin (ha) genes in which the ha1 and ha2 subunits of the ha molecule have been interchanged between influenza a/pr/8/34 (h1 subtype) and a/nt/60/68 (h3 subtype). these genes were used to construct recombinant vaccinia viruses that expressed intact chimeric ha. these recombinant viruses were used to test whether murine ctl recognize antigenic determinants in either the ha1, ha2, or both subunits. we found that both subunits of the ha molecule co ...19872442286
class i mhc molecules rather than other mouse genes dictate influenza epitope recognition by cytotoxic t cells.influenza nucleoprotein (np) is an important target antigen for influenza a virus cross-reactive cytotoxic t cells (tc). here we examine the np epitope recognized by cloned and polyclonal balb/c tc and the genetics of this recognition pattern. we can define np residues 147-161 as the epitope seen in conjunction with kd, the only h-2d class i responder allele for np restriction. h-2d/h-2b f1 mice (c57bl x dba/2) primed by influenza infection lyse only h-2d target cells treated with peptide 147-16 ...19872443447
modulation by immunosuppressive agents of peripheral blood mononuclear cell responses to influenza a virus.the response to influenza a virus of peripheral blood mononuclear cells (pbmc) isolated from normal healthy adults was studied by measuring antigen-specific lymphocyte proliferation and interferon and interleukin-2 production by these cells in vitro. under various experimental conditions, methylprednisolone, doxorubicin, vincristine, and vinblastine each reduced lymphocyte proliferation of the pbmc exposed to influenza a virus antigen. treatment of cells with these drugs did not reduce expressio ...19872444663
[antigenic specificity of the neuraminidases of epidemic strains of influenza a/h3n2 viruses circulating in the ussr 1983-1985].the antigenic properties of neuraminidase of the epidemic strains of 1983-1985 were studied by means of lectin test and thiobarbituric method using polyclonal sera and monoclonal antibody. populations of the viruses with respect to antigenic relationships of neuraminidase were shown to be heterogeneous. a considerable portion of the strains occurring in 1985 underwent antigenic drift from the reference a/philippines/2/82 strain. the epidemic novelty of some strains was due to changes in only one ...19872445104
regulation of the replication of influenza virus rna segments: partial suppression of protein synthesis restores the 'early' replication pattern.the replication of influenza virus rna was monitored by rna-rna hybridization with subsequent analysis of hybrid duplexes, as well as by immunosorption of viral nucleocapsids from extracts of [3h]uridine-labelled cells followed by the isolation and characterization of nucleocapsid-associated rna. the nucleocapsid-associated rna preparations contained mostly negative-strand genomic rna. electrophoresis of the hybrid rna duplexes or single-stranded nucleocapsid-associated rna in polyacrylamide gel ...19872445906
distinct epitopes recognized by i-ad-restricted t-cell clones within antigenic site e on influenza virus hemagglutinin.a total of 14 i-ad-restricted helper t-cell clones specific for the hemagglutinin (ha) molecule of influenza virus were isolated from spleens of balb/c or (balb/c x c57bl/10)f1 mice immunized with the h3 subtype influenza virus a/memphis/71 (mem 71) and from lymph nodes of balb/c mice primed with purified ha. the specificity of these t-cell clones was assessed in proliferation assays by reactivity with naturally occurring strains of viruses that arose by antigenic drift and contain known amino a ...19882446016
genomic rnas of influenza viruses are held in a circular conformation in virions and in infected cells by a terminal panhandle.the viral rna segments in influenza virions were shown to be circular in conformation by using psoralen crosslinking methods. electron microscopy of purified rna following treatment of virus with the psoralen reagent 4'-aminomethyltrioxsalen (amt) revealed circles with lengths corresponding to the individual segments. rna blot analysis using polyacrylamide gels demonstrated that rna from amt-treated virus had a slowed migration, consistent with it being a single-stranded circle. furthermore, nuc ...19872446318
experimental influenza infection: influence of stress.the effect of immobilization stress on the course of various forms of influenza infection has been investigated. influenza was produced in 10-14-week-old inbred mice by intranasal infection with pathogenic influenza virus strain a/pr/8/34 (h1n1) at different doses. immobilization for 6 hr resulted in the appearance of virus-inhibiting activity in the serum of mice. this activity suppressed the reproduction of test-virus in tissue culture, it was resistant to acid ph 2.0 treatment and to heating ...19872446485
[involvement of the afterbirth in influenza].light- and fluorescence-microscopy examinations of 186 placentas were carried out, with concurrent determination of placental interferon, isolation of influenza virus, and serologic tests of maternal and fetal blood, and amniotic fluid. in 32 of the cases, placentitis caused by serotype a or b of influenza virus was present, characterized by hyperplasia and subsequent destruction of amniotic cells, trophoblast, decidual cells, and vascular endothelium, by the presence of influenza antigens, fuch ...19872446593
antiviral chemotherapy and prophylaxis of viral respiratory disease.respiratory viruses continue to be major causes of morbidity and mortality. currently available chemotherapy is limited to oral amantadine for uncomplicated influenza a and aerosolized ribavirin for respiratory syncytial virus (rsv) infections. amantadine is also efficacious for chemoprophylaxis of influenza a virus infections. rimantadine has similar clinical efficacy and is better tolerated than amantadine. aerosolized ribavirin may be useful in the treatment of serious respiratory illness cau ...19872446820
comparative investigation of monoclonal and polyclonal antibodies directed against strain-specific and common antigenic sites on influenza h1n1 virus hemagglutinin.antibodies directed against strain-specific and common antigenic sites of h1n1 influenza virus hemagglutinin were tested comparatively, using monoclonal antibodies raised against strain a/brazil/11/78 and polyclonal antibodies directed against strains a/brazil/11/78, a/ussr/97/77, a/pr/301/54, and a/fm/1/47. the patterns of competition between antibodies for adsorption onto homologous virus indicated that the monoclonals comprised antibodies directed to each of the two strain-specific (sa and sb ...19872447032
epitopes of an influenza viral peptide recognized by antibody at single amino acid resolution.antibodies raised against the synthetic peptide corresponding to the carboxy-terminal 24 amino acids (305-328) of the heavy chain of the hemagglutinin molecule of influenza virus a/x-31 (h3) bind this peptide at three antigenic sites. these sites were identified by assaying binding of polyclonal balb/c mouse antipeptide sera to the complete set of all possible di-, tri, tetra-, penta-, hexa-, hepta-, and octapeptides homologous with the 24-residue sequence. individual epitopes were defined and e ...19882447184
role of interferon in leukocyte histamine release caused by common respiratory viruses.asthmatic attacks are often precipitated by viral respiratory infections. the mechanism of virus-induced asthma is still unclear. interferon could be an important mediator in virus-induced hypersensitivity reactions, because interferon is induced by some respiratory viruses, and it can enhance ige-mediated histamine release in vitro. we studied the effect of common respiratory viruses, including both interferon inducers and non-interferon inducers, on ige-mediated leukocyte histamine release. le ...19882447197
antiviral drugs for common respiratory diseases. what's here, what's to come.progress is being made in the development of drugs for the prevention and treatment of viral respiratory infections. two drugs currently available to clinicians are amantadine (symmetral) and ribavirin (virazole). oral amantadine is effective for both treatment and prevention of uncomplicated influenza a infections. although vaccination continues as the mainstay of influenza prevention, amantadine is useful for unvaccinated patients if complications are likely. when used for treatment, it must b ...19882448762
enhanced recognition of a modified peptide antigen by cytotoxic t cells specific for influenza nucleoprotein.a previously identified kd restricted epitope of influenza a virus nucleoprotein (147-161) was modified, resulting in recognition by kd restricted cytotoxic t cells at significantly lower concentrations than the natural peptide sequence. this was achieved by first refining the epitope to the minimum determinant 147-158. deletion of arginine 156 resulted in a peptide that was shown to be greatly superior in both dose response titrations and in its rate of association with cells to form targets. a ...19882449284
ha2 subunit of influenza a h1 and h2 subtype viruses induces a protective cross-reactive cytotoxic t lymphocyte response.influenza h1 subtype-specific ctl can be induced by secondary stimulation of a hybrid protein of the first 81 amino acids of the viral ns1 non-structural protein and the ha2 subunit of a/puerto rico/8/34(h1n1) hemagglutinin. in addition, a derivative of this protein with 65 amino acids deleted from the n-terminal end of ha2 can also generate h1 subtype-specific ctl in bulk cultures. ctl clones established by stimulation with the derivative protein demonstrated cross-reactive lysis of target cell ...19882449498
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