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1.
J Fish Biol ; 86(5): 1587-600, 2015 May.
Article in English | MEDLINE | ID: mdl-25943148

ABSTRACT

This study investigates the age and growth of Lutjanus argentimaculatus at its southern (cooler) range limits in eastern Australia. Specimens were collected from New South Wales and southern Queensland between November 2011 and December 2013. Fork lengths (LF ) ranged from 190 to 1019 mm, and ages ranged from 2+ to 57+ years. Growth was described by the von Bertalanffy growth function with coefficients L∞ = 874·92 mm, K = 0·087 year(-1) and t0 = -2·76 years. Estimates of the instantaneous natural mortality rate (M) ranged from 0·072 to 0·25. The LF (mm) and mass (W; g) relationship was represented by the equation: W=2·647×10-5LF2·92. The maximum age of 57+ years is the oldest reported for any lutjanid and comparisons with tropical studies suggest that the age-based demography of L. argentimaculatus follows a latitudinal gradient. High maximum ages and low natural mortality rates indicate considerable vulnerability to overexploitation at the species' cool-water-range limits. These results demonstrate the need to identify underlying processes driving latitudinal gradients in fish demography.


Subject(s)
Perciformes/growth & development , Animals , Body Size , Ecosystem , Female , Male , Models, Theoretical , New South Wales , Otolithic Membrane/growth & development , Queensland
2.
Biochemistry (Mosc) ; 67(6): 640-50, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12126471

ABSTRACT

A panel of fourteen different monoclonal antibodies was used for detection and analysis of antigenic determinants located on the outer surface protein A (OspA) of the spirochete Borrelia burgdorferi, which is a causative agent of tick-borne borreliosis (Lyme disease). Two main and several minor partially overlapping antigenic determinants have been found on the surface of the OspA protein of Borrelia burgdorferi sensu stricto (strain 297) by lanthanide competition fluoroimmunoassay. One of the main antigenic determinants is located in the N- and the other in the C-half of the OspA molecule. The involvement of the OspA protein in intact Borrelia burgdorferi sensu stricto (four bacterial strains have been analyzed: 297, B31, FR90-594, and CA90-742) is associated with retention of the above-mentioned two major antigenic determinants, but unlike the case of the isolated OspA they are partially overlapping with each other and with other antigenic determinants. The protein of the spirochete Borrelia afzelii (two bacterial strains have been analyzed: Ip-21 and Pko) contains only one antigenic determinant, which is the same as the main determinant of the OspA protein of Borrelia burgdorferi sensu stricto located in the N-half of the OspA molecule.


Subject(s)
Antigens, Surface/immunology , Bacterial Outer Membrane Proteins/immunology , Bacterial Proteins/immunology , Borrelia burgdorferi/immunology , Epitope Mapping/methods , Lipoproteins , Antibodies, Bacterial/immunology , Antibodies, Monoclonal/immunology , Bacterial Vaccines , Epitopes, B-Lymphocyte/immunology , Europium/metabolism , Fluorescent Antibody Technique
3.
J Immunol ; 166(12): 7381-8, 2001 Jun 15.
Article in English | MEDLINE | ID: mdl-11390489

ABSTRACT

Fc receptors for IgG expressed on macrophages and NK cells are important mediators of opsonophagocytosis and Ab-dependent cell-mediated cytotoxicity. Phagocyte-mediated opsonophagocytosis is pivotal for protection against bacteria, but its importance in recovery from infection with intracellular pathogens is unclear. We have now investigated the role of opsonophagocytosis in protection against lethal influenza virus infection by using FcR gamma(-/-) mice. Absence of the FcR gamma-chain did not affect the expression of IFN-gamma and IL-10 in the lungs and spleens after intranasal immunization with an influenza subunit vaccine. Titers of serum and respiratory Abs of the IgM, IgG1, IgG2a, and IgA isotypes in FcR gamma(-/-) mice were similar to levels seen in FcR gamma(+/+) mice. Nevertheless, FcR gamma(-/-) mice were highly susceptible to influenza infection, even in the presence of anti-influenza Abs from immune FcR gamma(+/+) mice. NK cells were not necessary for the observed Ab-mediated viral clearance, but macrophages were found to be capable of actively ingesting opsonized virus particles. We conclude that Fc receptor-mediated phagocytosis plays a pivotal role in clearance of respiratory virus infections.


Subject(s)
CD3 Complex , Influenza, Human/immunology , Influenza, Human/prevention & control , Phagocytosis/immunology , Receptors, Fc/physiology , Animals , Antibodies, Viral/biosynthesis , Cell Line , Cytokines/biosynthesis , Genetic Predisposition to Disease , Humans , Immune Sera/administration & dosage , Immunization, Passive , Immunoglobulin Isotypes/biosynthesis , Influenza A virus/immunology , Influenza, Human/genetics , Influenza, Human/virology , Injections, Intraperitoneal , Lung/immunology , Lung/metabolism , Macrophages/immunology , Macrophages/virology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Inbred CBA , Mice, Knockout , Mice, Transgenic , Receptors, Antigen, T-Cell/genetics , Receptors, Fc/deficiency , Receptors, Fc/genetics , Spleen/immunology , Spleen/metabolism
4.
J Immunol ; 166(1): 226-31, 2001 Jan 01.
Article in English | MEDLINE | ID: mdl-11123296

ABSTRACT

IgA is considered to be the principal Ab involved in defense against pathogens in the mucosal compartment. Using mice with a targeted disruption in IgA gene expression (IgA(-/-) mice), we have examined the precise role of IgA in protective anti-influenza responses after intranasal vaccination. IgA(-/-) mice immunized intranasally with soluble hemagglutinin (hemagglutinin subtype 1) and neuraminidase (neuraminidase subtype 1) vaccine in the absence of adjuvant were found to be more susceptible to influenza virus infection than IgA(+/+) mice (13 vs 75% survival after virus challenge). Inclusion of IL-12 during immunization restored the protective efficacy of the vaccine to that seen in IgA(+/+) animals. IgA(-/-) mice had no detectable IgA expression, but displayed enhanced serum and pulmonary IgM and IgG Ab levels after IL-12 treatment. Assessment of T cell function revealed markedly depressed splenic lymphoproliferative responses to PHA in IgA(-/-) animals compared with IgA(+/+) mice. Furthermore, IgA(-/-) animals displayed impaired T cell priming to the H1N1 subunit vaccine, with concomitant reduction in recall memory responses due to a defect in APC function. Collectively, these results provide evidence that a major role of IgA is to facilitate presentation of Ag to mucosal T cells. IL-12 treatment can overcome IgA deficiency by providing adequate T cell priming during vaccination.


Subject(s)
Genetic Predisposition to Disease , IgA Deficiency/genetics , IgA Deficiency/immunology , Influenza A virus/immunology , Influenza Vaccines/immunology , Orthomyxoviridae Infections/immunology , T-Lymphocytes, Helper-Inducer/immunology , Administration, Intranasal , Animals , Antibodies, Viral/biosynthesis , Antibodies, Viral/blood , Cells, Cultured , HN Protein/administration & dosage , HN Protein/immunology , IgA Deficiency/virology , Immunity, Innate/genetics , Immunoglobulin A/biosynthesis , Immunoglobulin A/blood , Immunologic Memory/genetics , Influenza Vaccines/administration & dosage , Interleukin-12/therapeutic use , Lymphocyte Activation/genetics , Lymphoproliferative Disorders/genetics , Lymphoproliferative Disorders/immunology , Mice , Mice, Inbred C57BL , Mice, Knockout , Orthomyxoviridae Infections/genetics , Orthomyxoviridae Infections/prevention & control , T-Lymphocytes, Helper-Inducer/metabolism , T-Lymphocytes, Helper-Inducer/virology
5.
Appl Environ Microbiol ; 64(12): 4663-9, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9835546

ABSTRACT

Ixodes scapularis, the tick vector of Lyme disease and human granulocytic ehrlichiosis (HGE), is prevalent in much of southern New York state. The distribution of this species has increased, as have reported cases of both Lyme disease and HGE. The unreliability of case reports, however, demonstrates the need for tick and pathogen surveillance in order to accurately define areas of high risk. In this study, a total of 89,550 m2 at 34 study sites was drag sampled in 1995 and a total of 51,540 m2 at 40 sites was sampled in 1996 to determine tick and pathogen distribution in southern New York state. I. scapularis was collected from 90% of the sites sampled, and regionally, a 2.5-fold increase in nymphal abundance occurred from 1995 to 1996. I. scapularis individuals from all sites were infected with Borrelia burgdorferi in 1995, while an examination of ticks for both B. burgdorferi and the agent of HGE in 1996 confirmed that these organisms were present in all counties; the average coinfection rate was 1.9%. No correlation was found between estimated risk and reported cases of Lyme disease. The geographic disparity of risk observed among sites in this study underscores the need for vector and pathogen surveillance on a regional level. An entomologic risk index can help identify sites for targeted tick control efforts.


Subject(s)
Borrelia burgdorferi Group/isolation & purification , Ehrlichia/isolation & purification , Ixodes/microbiology , Lyme Disease/epidemiology , Animals , Borrelia burgdorferi Group/genetics , Ehrlichia/genetics , Ehrlichiosis/epidemiology , Geography , Humans , New York/epidemiology , Polymerase Chain Reaction , Prevalence , Risk Assessment , Risk Factors
6.
New Microbiol ; 20(4): 355-9, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9385607

ABSTRACT

The Borrelia burgdorferi outer surface protein A (OspA) was quantified by an antigen-capture ELISA. The test detected 0.156 ng OspA/B, using purified rabbit IgG as a detection system. Dose-response relationship was described by a three-parameter equation and second degree polynomials. The estimated amount of OspA in host-attached Ixodes scapularis larvae was positively correlated with the tick's engorgement status, whereas the presence of blood in OspA-negative larvae reduced test absorbance. The antigen-capture ELISA can be effectively used in the ecology and epidemiology of Lyme borreliosis. However, host attached larvae should be matched by engorgement level to remove the effect of this variable on test results.


Subject(s)
Antigens, Surface/analysis , Bacterial Outer Membrane Proteins/analysis , Borrelia burgdorferi Group/immunology , Borrelia burgdorferi Group/isolation & purification , Ixodes/immunology , Ixodes/microbiology , Lipoproteins , Animals , Antigens, Surface/immunology , Arachnid Vectors/immunology , Arachnid Vectors/microbiology , Bacterial Outer Membrane Proteins/immunology , Bacterial Vaccines , Dose-Response Relationship, Immunologic , Enzyme-Linked Immunosorbent Assay/methods , Larva/immunology , Larva/microbiology , Mice , Peromyscus , Sensitivity and Specificity
7.
Antimicrob Agents Chemother ; 41(3): 687-92, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9056014

ABSTRACT

Matrix protein (M1) is a major structural protein of influenza virus, and it inhibits its own polymerase. A 19-amino-acid peptide, corresponding to a zinc finger region of the M1 sequence of influenza virus strain A/PR/8/34 (H1N1), centered around amino acids 148 to 166, was synthesized. This peptide, designated peptide 6, represents a zinc finger which includes a 7-amino-acid loop or finger and a 4-amino-acid tail at the carboxyl terminus, in addition to the 8 amino acids involved in the coordination of Zn. Three experiments were run to evaluate the activity of peptide 6 on infections induced in mice by influenza A/PR/8/34 and A/Victoria/3/75 (H3N2) viruses. Intranasal (i.n.) treatment of the H1N1 virus infection with 30 or 60 mg/kg of body weight/day, three times daily for 5 days, beginning 4 h pre-or 8 h post-virus exposure, was effective in preventing death, reducing the arterial oxygen decline, and inhibiting lung consolidation. Virus titers in the lungs determined on day 5 were reduced by up to 1.5 log10 in treated groups, but considerable variation in the titers of the recovered virus was seen. The H3N2 virus infection was treated i.n. with 30, 60, or 120 mg of peptide 6/kg/day by using the above-mentioned delayed initiation treatment schedule, and similar protection was seen, although lung virus titers were not reduced in the day-5 assay. Peptide 6 was well tolerated at doses up to 60 mg/kg/day. This zinc finger peptide may provide a new class of antivirals effective against influenza virus.


Subject(s)
Antiviral Agents/pharmacology , Influenza A virus/drug effects , Orthomyxoviridae Infections/drug therapy , Peptides/pharmacology , Zinc Fingers/physiology , Administration, Intranasal , Amino Acid Sequence , Animals , Antiviral Agents/administration & dosage , Antiviral Agents/therapeutic use , Female , Lung/virology , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Orthomyxoviridae Infections/virology , Oxygen/blood , Peptides/administration & dosage , Peptides/therapeutic use , Ribavirin/therapeutic use
8.
J Virol ; 70(12): 8639-44, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8970989

ABSTRACT

Matrix protein (M1) of influenza virus inhibits its own polymerase; this suggested that a peptide segment of M1 with inhibitory properties could serve as an antiviral agent. A peptide synthesized to the Zn2+ finger region of the M1 sequence of influenza virus strain A/PR/8/34 centered around amino acids residues 148 to 166 was shown earlier to be 1,000-fold more effective as a polymerase inhibitor than M1. This peptide, designated peptide 6, represents a Zn2+ finger which includes a 7-residue "loop" and a 4-residue "tail" in addition to the 4 residues on either side of the loop involved in coordination of Zn2+. We have now demonstrated antiviral activity for this peptide in microassays measuring inhibition of the viral cytopathic effect. When the peptide was introduced into tissue culture 5 min after viral challenge with A/PR/8/34, antiviral activity was seen at levels as low as 0.1 nM; on a molar basis, the peptide was shown to be 1,000- to 2,500-fold more effective than ribavirin or amantadine. Antiviral activity was seen with addition of the peptide up to 1 h after viral infection; however, little or no activity was seen at later times, suggesting that viral replication is inhibited at an early stage, possibly at the level of transcription. Reduction in the finger loop or tail length reduced antiviral activity; reduction in the number of residues involved in coordination of Zn2+ abolished antiviral activity. In addition to A/PR/8/34, peptide 6 was shown to have antiviral activity against other type A influenza viruses, including those representing H1N1, H2N2, and H3N2 subtypes. Antiviral activity against type B influenza viruses was also seen. A low level of activity against vesicular stomatitis virus was observed. Zn2+ finger peptides or analogs of Zn2+ finger peptides may provide a new class of antiviral agents effective against influenza virus and possibly other viruses.


Subject(s)
Antiviral Agents/pharmacology , Influenza A virus/drug effects , Influenza B virus/drug effects , Viral Matrix Proteins/pharmacology , Zinc Fingers , Amino Acid Sequence , Animals , Antiviral Agents/chemical synthesis , Cell Line , Dogs , Humans , Molecular Sequence Data , Peptides/chemical synthesis , Peptides/pharmacology , Structure-Activity Relationship , Time Factors , Viral Matrix Proteins/chemical synthesis
9.
J Virol ; 68(12): 8141-6, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7966605

ABSTRACT

Analysis of fast-growing reassortants (AWM viruses) of influenza A virus produced by mixed infection with a fast-growing WSN strain and a slowly growing Aichi strain indicated that the M gene plays a role in the regulation of virus growth rate at an early step of infection (J. Yasuda, T. Toyoda, M. Nakayama, and A. Ishihama, Arch. Virol. 133:283-294, 1993). To determine which of the two M gene products, M1 or M2, is responsible for the growth rate control, one recombinant WSN virus (CWA) clone possessing a chimeric M gene (WSN M1-Aichi M2) was generated by using an improved reverse genetics and transfection system. The recombinant CWA virus retained the phenotype of both large plaque formation and early onset of virus growth. This indicates that the WSN M1 protein is responsible for rapid virus growth.


Subject(s)
Influenza A virus/growth & development , Viral Matrix Proteins/metabolism , Amino Acid Sequence , Animals , Base Sequence , Cattle , Cell Line , Cells, Cultured , Chick Embryo , Cloning, Molecular , DNA Primers , Genes, Viral , Influenza A virus/genetics , Influenza A virus/metabolism , Kidney , Kinetics , Molecular Sequence Data , Phenotype , Polymerase Chain Reaction , Recombinant Fusion Proteins/biosynthesis , Recombination, Genetic , Restriction Mapping , Transfection , Viral Matrix Proteins/biosynthesis , Viral Plaque Assay
10.
Acta Virol ; 38(1): 5-10, 1994 Feb.
Article in English | MEDLINE | ID: mdl-7520664

ABSTRACT

Using 14 monoclonal antibodies (MoAbs) in solid-phase ELISA it was found that influenza virus A/Hong Kong/1/68 (H3N2) mutants resistant to the antiviral compound mopyridone as compared to the mopyridone-sensitive mutant manifested significant changes in the antigenic structure (sites 1A, 2 and 3) of M1 protein. No differences in M1 were found between rimantadine-resistant and rimantadine-sensitive mutants of influenza virus A(H3N2).


Subject(s)
Antiviral Agents/pharmacology , Influenza A virus/immunology , Pyrimidinones/pharmacology , Viral Matrix Proteins/immunology , Animals , Antibodies, Monoclonal , Antibodies, Viral , Antigens, Viral/immunology , Chick Embryo , Drug Resistance, Microbial , Enzyme-Linked Immunosorbent Assay , Epitopes/immunology , Influenza A virus/drug effects , Mutation , Rimantadine/pharmacology
11.
J Clin Microbiol ; 29(11): 2484-8, 1991 Nov.
Article in English | MEDLINE | ID: mdl-1774253

ABSTRACT

Monoclonal antibodies (MAbs) to the M protein (M1) were used in the development of direct detection systems for type A influenza viruses in clinical specimens. Optimal detection by an enzyme-linked immunosorbent assay was achieved when MAbs were used as capture antibodies and rabbit polyclonal antibodies were used as sandwich antibodies. Detection by the enzyme-linked immunosorbent assay required amplification of the virus. direct detection in clinical specimens (nasopharyngeal aspirates) was accomplished when MAbs recognizing two distinct antigenic sites of M1 were used in a time-resolved fluoroimmunoassay. Type A influenza viruses could be detected equally well in specimens obtained during epidemics of both H3N2 and H1N1 influenza viruses.


Subject(s)
Antibodies, Monoclonal , Influenza A virus/immunology , Influenza A virus/isolation & purification , Antigens, Bacterial , Enzyme-Linked Immunosorbent Assay , Fluoroimmunoassay , Humans , Influenza, Human/diagnosis , Influenza, Human/microbiology , Viral Matrix Proteins/immunology
12.
Proc Natl Acad Sci U S A ; 88(5): 1756-9, 1991 Mar 01.
Article in English | MEDLINE | ID: mdl-2000384

ABSTRACT

The effects of heme alone and heme administered together with 3'-azido-3'-deoxythymidine (AZT) on human immunodeficiency virus replication in human peripheral blood lymphocytes and in the H9 cell line were studied. Heme enhanced the antiviral action of AZT against both drug-resistant and drug-sensitive viral strains; the heme effect was more pronounced against the latter. Moreover, heme alone displayed a significant ability to inhibit viral replication in concentrations markedly smaller than those required to inhibit the reverse transcriptase of Rauscher murine leukemia virus. The results of this study extend the range of pharmacological actions that metalloporphyrins exert in biological systems and suggest that further study of the interactions of the natural compound heme and human immunodeficiency virus chemotherapeutic agents such as AZT may be useful.


Subject(s)
Antiviral Agents , HIV-1/physiology , Heme/pharmacology , Virus Replication/drug effects , Zidovudine/pharmacology , Cell Line , Cells, Cultured , Dose-Response Relationship, Drug , Drug Resistance, Microbial , Drug Synergism , HIV-1/drug effects , HIV-1/isolation & purification , Humans , Kinetics , Lymphocytes/microbiology
13.
Virus Genes ; 3(2): 111-26, 1989 Nov.
Article in English | MEDLINE | ID: mdl-2482574

ABSTRACT

Influenza virus M1 protein has been shown to inhibit viral RNA transcription, and in this study the epitopes on M1 critical for this function were localized. When a battery of 15 monoclonal anti-M1 antibodies were reacted with chemically cleaved fragments of M1 on a western blot, five distinct banding patterns were observed. A representative antibody was selected from each banding group, and its ability to reverse M1-effected transcription inhibition was measured. From these data, the sites on M1 critical for transcription inhibition were deduced. It appears now that the regions on M1 in the vicinity of amino acid residues #70 and #140 are critical for inhibition. Furthermore, by taking into account the hydropathicity and secondary structure, it is hypothesized that amino acids #70 and #140 are physically close together in the final three-dimensional conformation of M1 protein and that the residues in between form a loop and are thus removed from the functional site.


Subject(s)
Epitopes/analysis , Influenza A virus/genetics , Transcription, Genetic , Viral Matrix Proteins/analysis , Antibodies, Monoclonal , Immunoblotting , Neutralization Tests , RNA, Viral/genetics , Transcription, Genetic/drug effects , Viral Matrix Proteins/isolation & purification , Viral Matrix Proteins/pharmacology
14.
Virology ; 171(2): 634-6, 1989 Aug.
Article in English | MEDLINE | ID: mdl-2474896

ABSTRACT

A panel of monoclonal antibodies to the M1 protein of A/PR8/34 (H1N1) (PR8) influenza A virus was found to distinguish in ELISA high-yielding reassortant viruses derived from reassortment of PR8 and X-31 (H3N2) viruses with recently prevalent field strains of H1N1 or H3N2 subtype. These findings are concordant with results of genotyping that demonstrated the presence of PR8 RNA 7 or M1 protein in high-yield reassortants by RNA or protein PAGE. All high-yield vaccine candidate reassortants Application of the M1 monoclonal antibody panel facilitates the isolation of high-yield vaccine candidate reassortants bearing the PR8 M1 gene, and should aid in epidemiologic strain tracking as well.


Subject(s)
Antibodies, Monoclonal/immunology , Antigens, Viral/immunology , Influenza A virus/immunology , Viral Proteins/immunology , Antibodies, Viral/immunology , Blotting, Western , Enzyme-Linked Immunosorbent Assay , Epitopes
15.
J Virol ; 63(3): 1239-46, 1989 Mar.
Article in English | MEDLINE | ID: mdl-2915381

ABSTRACT

BALB/c mice immunized with graded doses of chromatographically purified hemagglutinin (HA) and neuraminidase (NA) antigens derived from A/Hong Kong/1/68 (H3N2) influenza virus demonstrated equivalent responses when HA-specific and NA-specific serum antibodies were measured by enzyme-linked immunosorbent assays (ELISAs). Antibody responses measured by hemagglutination inhibition or neuraminidase inhibition titrations showed similar kinetic patterns, except for more rapid decline in hemagglutination inhibition antibody. Injection of mice with either purified HA or NA resulted in immunity manifested by reduction in pulmonary virus following challenge with virus containing homologous antigens. However, the nature of the immunity induced by the two antigens differed markedly. While HA immunization with all but the lowest doses of antigen prevented manifest infection, immunization with NA was infection-permissive at all antigen doses, although reduction in pulmonary virus was proportional to the amount of antigen administered. The immunizing but infection-permissive effect of NA immunization over a wide range of doses is in accord with results of earlier studies with mice in which single doses of NA and antigenically hybrid viruses were used. The demonstrable immunogenicity of highly purified NA as a single glycoprotein without adjuvant offers a novel infection-permissive approach with potentially low toxicity for human immunization against influenza virus.


Subject(s)
Antibodies, Viral/biosynthesis , Hemagglutinins, Viral/immunology , Influenza A virus/immunology , Neuraminidase/immunology , Animals , Dose-Response Relationship, Immunologic , Immunization , Immunologic Memory , Membrane Glycoproteins/immunology , Mice , Mice, Inbred BALB C , Orthomyxoviridae Infections/immunology , Orthomyxoviridae Infections/prevention & control , Time Factors
16.
J Immunol Methods ; 96(1): 77-85, 1987 Jan 26.
Article in English | MEDLINE | ID: mdl-3027185

ABSTRACT

A model system has been developed which permits rapid detection of influenza viruses through targeting of the M (membrane or matrix)-protein; a type-specific antigen, in an enzyme-linked immunosorbent assay system. This technique exploits the hydrophobic properties of M-protein; the M-protein is selectively and rapidly adsorbed to polystyrene surfaces even in the presence of a 5000-fold excess of bovine serum albumin. Hyperimmune antiserum prepared to purified M-protein is used as the detecting reagent. All type A influenza viruses could be detected by this technique, type B influenza viruses reacted to a slight extent and Sendai virus (parainfluenza virus, type 1) did not react. Virus could be detected to levels as low as 3 ng. Purification of M-protein and preparation of hyperimmune sera from other related virus groups, such as type B influenza viruses, paramyxoviruses and rhabdoviruses should permit detection of these agents by a similar technique.


Subject(s)
Antigens, Viral/analysis , Enzyme-Linked Immunosorbent Assay/methods , Orthomyxoviridae/isolation & purification , Viral Proteins/analysis , Adsorption , Antibodies, Viral/immunology , Antigens, Viral/immunology , Orthomyxoviridae/immunology , Parainfluenza Virus 1, Human , Polystyrenes , Viral Matrix Proteins , Viral Proteins/immunology
17.
Biochim Biophys Acta ; 778(2): 269-75, 1984 Dec 05.
Article in English | MEDLINE | ID: mdl-6498192

ABSTRACT

Alterations in the surface potential difference (delta U) of asolectin planar bilayer lipid membranes were measured following the adsorption of isolated matrix protein (M-protein) or neuraminidase of influenza virus. The method used was based upon measurement of the bilayer lipid membrane capacitance current second harmonic. The delta U dependence on the M-protein and neuraminidase concentration indicates different mechanisms of adsorption of these viral proteins by the lipid bilayer. The conductance (G0) dependence of the bilayer lipid membrane with different compositions on the concentration of isolated surface glycoproteins, hemagglutinin and neuraminidase, M-protein or neuraminidase was investigated. The change in G0 for M-protein was observed only after adsorption saturation had been achieved. Neuraminidase alone does not affect the membrane conductivity. The surface charge and lipid composition of the lipid bilayer influences the adsorption and incorporation of influenza virus M-protein and surface glycoproteins. The reversibility of protein incorporation into the bilayers was investigated by a perfusion technique. The results show reversibility of surface glycoprotein incorporation while M-protein binding appears to be irreversible.


Subject(s)
Lipid Bilayers/metabolism , Viral Proteins/metabolism , Adsorption , Glycoproteins/metabolism , Kinetics , Permeability , Phosphatidylcholines , Phospholipids/metabolism , Surface Properties , Viral Matrix Proteins
18.
Biochim Biophys Acta ; 778(2): 276-80, 1984 Dec 05.
Article in English | MEDLINE | ID: mdl-6498193

ABSTRACT

The dependence of the surface potential difference (delta U), transversal elasticity module (E1) and membrane conductivity (G0) on the concentrations of the antiviral drugs, rimantadine and amantadine was studied in the planar bilayer lipid membrane system. The method used was based on independent measurements of the second and third harmonics of the membrane capacitance current. The binding constants of bilayer lipid membranes obtained from the drug adsorption isotherms were 2.1 X 10(5) M-1 and 1.3 X 10(4) M-1 for rimantadine and amantadine, respectively. The changes in G0 took place only after drug adsorption saturation had been achieved. The influence of rimantadine and amantadine on the interaction of bilayer lipid membranes with matrix protein from influenza virus was also investigated. The presence of 70 micrograms/ml rimantadine in the bathing solution resulted in an increase in the concentration of M-protein at which the adsorption and conductance changes were observed. The effects of amantadine were similar to those of rimantadine but required a higher critical concentration of amantadine. The results obtained suggest that the antiviral properties of rimantadine and amantadine may be related to the interaction of these drugs with the cell membrane, which can affect virus penetration into the cell as well as maturation of the viral particle at the cell membrane.


Subject(s)
Adamantane/analogs & derivatives , Amantadine/pharmacology , Lipid Bilayers/metabolism , Rimantadine/pharmacology , Viral Proteins/metabolism , Dose-Response Relationship, Drug , Kinetics , Membrane Potentials , Phosphatidylcholines , Phospholipids/metabolism , Viral Matrix Proteins
19.
J Clin Microbiol ; 20(1): 89-93, 1984 Jul.
Article in English | MEDLINE | ID: mdl-6205018

ABSTRACT

Neuraminidases were purified from reassortant viruses (H6N1 and H6N2) containing the two antigenic subtypes (N1 and N2) found in human influenza viruses. Surface glycoproteins were solubilized with octylglucoside, and the neuraminidase was isolated by chromatography on DEAE-Sephadex. Neuraminidase isolated by this technique coeluted with viral lipids and spontaneously formed liposomes on dialysis. The purified neuraminidase was immunogenic in rabbits, producing a significant antibody response at dose levels as low as 1 microgram.


Subject(s)
Antigens, Viral/analysis , Influenza A virus/enzymology , Neuraminidase/isolation & purification , Animals , Chromatography , Electrophoresis, Polyacrylamide Gel , Epitopes/analysis , Humans , Influenza A virus/immunology , Neuraminidase/immunology , Rabbits
20.
J Clin Microbiol ; 16(5): 813-20, 1982 Nov.
Article in English | MEDLINE | ID: mdl-6759527

ABSTRACT

An enzyme-linked immunosorbent assay test system was developed in which purified influenza virus M protein was used for the detection of M antibody in human sera. Antibody levels to influenza A virus M protein were monitored in sera from a vaccine study population by using an enzyme-linked immunosorbent assay technique with purified M protein as the adsorbent antigen. A 10-fold variation in titers of preexisting M antibody was observed in this population of young adults. Increases of anti-M titer of 7- to 24-fold were observed upon immunization with Formalin-inactivated vaccine or after natural infection. The antibody response to M protein was dissociated from the response to the hemagglutinin or neuraminidase antigens. The M antibody response preceded or was coincident with the antibody response to H1 hemagglutinin upon natural exposure to circulating virus.


Subject(s)
Antibodies, Viral/analysis , Blood Proteins/immunology , Enzyme-Linked Immunosorbent Assay , Immunoenzyme Techniques , Immunoglobulins , Orthomyxoviridae/immunology , Antibody Formation , Hemagglutination Inhibition Tests , Vaccination
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