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B Forghani

Publications and source records attributed to B Forghani.

At least 55 records · Page 3Linked to original sources
PubMed1984

Varicella-zoster viral glycoproteins analyzed with monoclonal antibodies.

Monoclonal antibodies to varicella-zoster virus were used to study viral glycoproteins by immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Based on the viral glycoproteins immunoprecipitated, the five monoclonal antibodies fell into three groups. Two antibodies, 4B7 and 8G9 (group 1), immunoprecipitated a single glycoprotein of molecular weight (MW) 118,000 (118K glycoprotein) and had high neutralizing activity in the absence of complement. One antibody, 3C7 (group 2), which lacked neutralizing activity, immunoprecipitated two glycoproteins of MWs 120,000 and 118,000 and a glycoprotein giving a diffuse band in the region of 64,000 to 65,000. Pulse-chase experiments and experiments with monensin as an inhibitor of glycosylation suggested that the 120K polypeptide was derived by glycosylation of the 118K polypeptide and that a 43K antigen was processed into the 64 to 65K glycoprotein. Two antibodies, 3G8 and 4E6 (group 3), both had neutralizing activity only in the presence of complement, and both immunoprecipitated at least five polypeptides, with MWs ranging from 50,000 to 90,000. Antibody 3G8 was isotype immunoglobulin G2b (IgG2b), and its immunoprecipitating activity was stronger than that of 4E6, which was isotype IgG1. Pulse-chase experiments with antibody 3G8 showed that lower-MW glycopeptides chased into three polypeptides of MWs 90,000, 80,000, and 60,000 by 24 h. Immunoprecipitation experiments with antibody 3G8 on infected cells treated with glycosylation inhibitors 2-deoxyglucose, monensin, and tunicamycin, suggested that a prominent, early-appearing 70K polypeptide may have been processed into the glycoproteins of higher MWs and that the 60K polypeptide may have been derived by glycosylation of polypeptides of lower MWs.

Antibodies, Monoclonal↗
PubMed1983

Association of herpes simplex virus with platelets of experimentally infected mice.

In mice infected with herpes simplex virus (HSV) type 1 by the intracerebral route or with HSV type 2 by the vaginal route, virus was shown to be present in greater quantities in purified platelets than in leucocytes or other blood components. Results of the studies described suggest that platelets may play a major role in the hematogenous dissemination of HSV infection.

Animals↗
PubMed1983

Use of monoclonal antibodies to human immunoglobulin M in "capture" assays for measles and rubella immunoglobulin M.

Monoclonal antibodies to human immunoglobulin M (IgM) were used in a four-phase enzyme immunofluorescence "capture" assay for determination of IgM antibodies to measles and rubella viruses. Little or no background reactivity was seen in the test system, and interfering effects of rheumatoid factor were avoided by preabsorption of test sera with aggregated human IgG. Virus-specific IgM antibody was demonstrable in 23 of 24 patients with serological evidence of measles virus infections and in 36 of 36 patients with serological evidence of postnatal rubella infection. A few of the rubella patients did not show IgM antibody until 5 days after onset of illness. The enzyme immunofluorescence assay was able to demonstrate rubella IgM antibody in congenitally infected newborns, whereas indirect immunofluorescence results for virus-specific IgM were negative. Viral IgM antibody was not detected in persons with past infections with the test viruses, in young children without evidence of past infection, or in patients infected with heterotypic viruses, rickettsiae, chlamydiae, or mycoplasmas.

Antibodies, Monoclonal↗
PubMed1982

Serological reactivity of some monoclonal antibodies to varicella-zoster virus.

Monoclonal antibodies to varicella-zoster virus, free from host cell reactivity, were produced by cell fusion technics. Antibodies from four different clones showed diverse activities in neutralization immunofluorescence and complement fixation assays. The antibodies provide useful reagents for viral diagnosis and viral antigenic characterization.

Animals↗
PubMed1982

Production of monoclonal antibodies to human IgM for assay of viral IgM antibodies.

Monoclonal antibodies to human IgM were produced by fusing the Sp 2/0-Ag 14 line of mouse myeloma cells with spleen cells from BALB/c mice immunized with purified human IgM. From 6 clones which secreted antibody to human IgM, the one which produced the highest levels of antibody and grew relatively rapidly was selected for expansion and production of immune reagents for viral IgM antibody assays. Mouse ascitic fluids produced with this clone of cells had antibody titers for human IgM of 1 X 10(-10) by indirect enzyme immunofluorescence assay (EIFA). The monoclonal antibodies were found to belong to subclass 1 of murine IgG, and their specificity was shown to be directed against the Fab portion of the mu chain of human IgM. Antibodies from murine ascitic fluid conjugated with horseradish peroxidase were shown to be suitable for assay of measles IgM antibody by indirect immunoperoxidase staining. Antibodies conjugated with alkaline phosphatase could be used in an indirect EIFA for determination of measles IgM antibodies; use of monoclonal conjugates in this system eliminated the nonspecific activity observed in tests utilizing polyclonal anti-mu reagents. Further, the monoclonal antibodies were highly satisfactory for use in a 'capture' system for viral IgM antibody assays. The availability of monoclonal antibodies to human IgM overcomes problems with specificity, consistency and supply which have previously hindered development and standardization of viral IgM antibody assays.

Animals↗
PubMed1980

Comprehensive viral immunology of multiple sclerosis. III. Analysis of CSF antibodies by radioimmunoassay.

The CSF from 279 patients with multiple sclerosis (MS), probable MS, or controls was examined by radioimmunoassay (RIA) for antibodies to measles, rubella, mumps, parainfluenza 1 (Sendai) (strain 6/94), herpes simplex (HSV), varicella, and vaccinia viruses. Significantly more patients with MS than noninflammatory control patients had antibody to measles, rubella and varicella viruses, of which antibody to measles was the most prevalent. The percentage of patients with MS with two or more CSF antibodies was significantly greater than that in the controls. There was no tendency for certain antibodies to be associated. There was a general relationship between presence of CSF antibodies and severity of MS. The data support the hypothesis of local CNS antibody synthesis of several viral antibodies; however, such local synthesis may be a random event, possibly dependent on the number and specificity of peripheral virus antibody-forming lymphocytes available for ingress into the CNS.

Albumins↗
PubMed1980

Humoral immune response to virions and dense bodies of human cytomegalovirus determined by enzyme immunofluorescence assay.

An enzyme immunoassay utilizing a fluorogenic substrate (EIFA) was employed to compare humoral antibody responses to purified virion and dense body antigens in human cytomegalovirus (CMV) infections. Results of these antibody assays were also compared to those obtained by plaque reduction neutralization and complement fixation (CF). In adults with CMV infections diagnosed by a significant rise in CF antibody titer, there was also a vigorous antibody response to the virion and dense body antigens. There was better correlation between antibody levels to the virion and dense body antigens than between antibody levels detected by other combinations of tests. Antibody responses to the virion and dense body antigens were similar, but not identical, suggesting that although the two structures share major antigens, they may also possess unique antigens to which the host can mount independent antibody responses. All individuals with CMV neutralizing antibody also had virion and dense body antibodies, but there was poor correlation between neutralization titers and those detected by EIFA, perhaps reflecting greater strain specificity of the neutralization test. Some individuals with serological diagnoses of Mycoplasma pneumoniae or influenza A infection showed fourfold or greater antibody titer rises to CMV in two or more assays, suggesting reactivation of latent CMV in these infections.

Antibodies, Viral↗
PubMed1979

Antigen requirements, sensitivity, and specificity of enzyme immunoassays for measles and rubella viral antibodies.

Enzyme immunoassay (EIA) systems for measles virus and rubella virus were studied from the standpoints of requirements for suitable viral antigens and control antigens, and the sensitivity and specificity of the tests for detecting antibody elicited by past infection (determination of immunity status), and for serodiagnosis of currenet infections. Crude or semipurified measles virus antigens were satisfactory for EIA, but antigens derived by pelleting virus from infected cell culture fluids were slightly more specific in their reactivity than were antigens produced from lysates of infected cells. However, reliable rubella EIA antigens could be produced only from infected cell culture fluids, and they required density gradient purification to render them suitably specific. Even with gradient-purified rubella antigens, it was necessary to use antigen prepared in an identical fashion from uninfected cell culture fluids as a control on the specificity of reactions obtained with test sera. With appropriate viral antigens and control antigens, both measles and rubella EIA systems were highly sensitive and specific for determination of immunity status and for serodiagnosis of current infections. Antibody was detectable earlier in the course of infection by EIA than by hemagglutination inhibition or complement fixation, but this did not limit the diagnostic value of the test, since titer increases demonstrable by EIA were usually greater than those detectable by hemagglutination inhibition or complement fixation tests.

Antibodies, Viral↗
PubMed1979

Rotavirus antibody assays on monkey sera: a comparison of enzyme immunoassay with neutralization and complement-fixation tests.

An enzyme immunoassay (EIA) for the detection of rotaviral antibodies was developed, using a purified, cell culture-grown SA 11 viral antigen and alkaline phosphatase as an enzyme label. This technique was evaluated by comparative testing with tube neutralization and complement-fixation assays on a collection of simian sera. There was close correlation between positive and negative results obtained by EIA and by neutralization. The EIA was as easy to perform as complement fixation testing, but showed greater sensitivity and fewer nonspecific reactions. Thus, EIA was shown to be a very suitable test for routine detection of rotaviral antibodies in serum. Results of neutralization tests suggested that the monkeys (mostly rhesus macaques) in the present study were infected with viruses varying in their antigenic relatedness to SA 11 virus and to a British isolate of calf rotavirus.

Animals↗
PubMed1978

Viral antibodies in cerebrospinal fluid of multiple sclerosis and control patients: comparison between radioimmunoassay and conventional techniques.

Cerebrospinal fluid antibodies to measles, rubella, vaccinia, herpes simplex, and varicella-zoster viruses in four patient study groups (clinically definite multiple sclerosis [MS], early probable MS, optic neuritis, and control patients with other neurological diseases) were assayed by radioimmunoassay, complement fixation, hemagglutination-inhibition, or complement-enhanced plaque reduction methods. Antibodies were more frequently found and at higher dilutions by radioimmunoassay than by other techniques. Measles virus antibody, the most frequently found antibody, was present in the cerebrospinal fluid of 72% of MS patients and 5% of control patients. The differences between the numbers of MS patients and control patients with antibodies to other viruses were not as marked. Thus, 58% of MS patients versus 21% of control patients had antibody to rubella virus, 20 versus 3% had antibody to vaccinia virus, 50 versus 33% had antibody to herpes simplex virus, and 25 versus 8% had antibody to varicella virus. Sixty-seven percent of MS patients and 26% of control patients had antibodies to two or more viruses in their cerebrospinal fluid.

Adolescent↗
PubMed1978

Antibody assays for varicella-zoster virus: comparison of enzyme immunoassay with neutralization, immune adherence hemagglutination, and complement fixation.

An enzyme immunossay (EIA) was adapted for detection of antibody to varicella-zoster virus, and its sensitivity and specificity were compared with those of neutralization, immune adherence hemagglutination (IAHA), and complement fixation tests. Test sera showed little nonspecific reactivity in the EIA system, and valid results could usually be obtained at serum dilutions as low as 1:8. Demonstration of the presence or absence of varicella-zoster viral antibody by EIA showed 94% correlation with results obtained in neutralization tests, but EIA titers were 2- to 16-fold higher than neutralizing antibody titers. Results by IAHA showed 87% correlation with those obtained by neutralization. No false positive IAHA results were seen, but a number of false negative IAHA results were seen at the 1:8 serum dilution, particularly in older individuals. With increasing age (>40 years), and presumably increased time from varicella infection, neutralizing antibody levels generally declined to 1:8 or 1:16, EIA levels fell to 1:128 or 1:256, and IAHA and complement fixation antibody titers were usually <1:8 or 1:8. EIA and IAHA were as reliable as the neutralization and complement fixation tests for serodiagnosis of varicella and zoster infections. All tests demonstrated heterotypic varicella-zoster antibody titer rises in selected patients with initial herpes simplex virus infections, but fewer heterotypic responses were seen by EIA than by the other methods. EIA offers a rapid, sensitive, and specific method for varicella-zoster antibody assay that is applicable to use in a clinical setting.

Adolescent↗
PubMed1977

Radioimmunoassay inhibition method for confirming the specificity of positive hepatitis B surface antigen reactions and for survey of antibodies to the antigen.

Studies were conducted to determine the hepatitis B surface antigen antibody (anti-HBS) levels and antibody subtype specificities required in order for anti-HBS sera of human origin to be suitable for use in radioimmunoassay (RIA) inhibition tests for determining the specificity of positive reactions for hepatitis B surface antigen (HBSAg). Also, the RIA inhibition method was evaluated for detection of anti-HBS in sera of laboratory personnel. Only anti-HBS sera with complement-fixing (CF) antibody titers of 1:32 or higher effectively inhibited HBSAg-positive sera with demonstrable CF activity, and complete inhibition was obtained only for antigens having CF titers of 1:64 or lower. Higher-titered antigens could be inhibited when diluted 1:10-1:100. The low-titered HBSAg preparation supplied with AusRIA kits (Abbott Laboratories) was effectively inhibited by low-titered anti-HBS sera, and when used in RIA inhibition tests on sera from laboratory personnel, the tests detected anti-HBS in approximately 14% of the individuals tested, a slightly greater number than those showing anti-HBS in passive hemagglutination tests. Inhibition of HBSAg-positive sera by the anti-HBS sera could not be related to the d and y subtype specificities of the antigens or antisera; the antisera were no more effective in inhibiting antigens of the homologous subtype than those of the heterologous subtype.

Animals↗
PubMed1976

Antisera to human cytomegalovirus produced in hamsters: reactivity in radioimmunoassay and other antibody assay systems.

Hamsters immunized with human cytomegalovirus (CMV) concentrated and purified by polyethylene glycol precipitation and density gradient centrifugation produced antisera with high titers of specific viral antibody, and which showed no significant reactivity with human host cell components. The antisera had high titers of CMV antibody in complement fixation, indirect fluorescent-antibody (FA), and neutralization tests, but titers obtained by indirect radioimmunoassay (RIA) were markedly higher. The antisera were used to follow the development of CMV antigen in infected host cells by indirect RIA and indirect FA staining. Virus-specific antigen was first detectable by RIA at 8 h after infection, and by FA staining at 16 h; cells contained optimal amounts of antigen for RIA and FA assays at 72 to 100 h postinfection. Immune globulins from the antisera were labeled with 125I for use in direct RIA. The labeled globulins gave highly specific reactions with CMV-infected cells, including those infected with low-passage isolates, and showed no reactivity with cells infected with other human herpesviruses or certain other human viruses.

Animals↗
PubMed1976

Sensitivity of a radioimmunoassay method for detection of certain viral antibodies in sera and cerebrospinal fluids.

An indirect solid-phase radioimmunoassay (RIA) was applied to titration of serum and cerebrospinal fluid (CSF) antibodies against a variety of viruses including rubella, mumps, measles, herpes simplex, varicella-zoster, and vaccinia. The test used fixed, virus-infected cells as a source of antigen, and conditions for optimal production of viral antigen were determined for each virus-host cell system. In acute, uncomplicated viral infections, sera taken 2 to 5 days after onset generally had low homotypic RIA titers ranging from less than 1:100 to 1:500, whereas convalescent-phase titers ranged from 1:128,000 to 1:512,000. Rubella and measles antibody titers as high as 1:256,000 were demonstrated by RIA in CSF from patients with chronic panencephalitis, whereas homologous antibody titers of 1:4,000 were detected in CSF from acute mumps, herpes simplex, and varicella-zoster virus infections with central nervous system involvement. Some heterotypic antibody was demonstrable by RIA in CSF, but, with the exception of herpes simplex antibody in a mumps virus infection, titers were markedly lower than those to the infecting virus type. RIA generally demonstrated titers at least 1,000 times higher than those obtained by conventional assays such as complement fixation, hemagglutination inhibition, neutralization, and immunofluorescent staining.

Acute Disease↗