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Biomedical subjects

K O Smith

Publications and source records attributed to K O Smith.

At least 37 records · Page 2Linked to original sources
PubMed1979

Simultaneous radioimmunoassay for specific antibodies to members of the human herpesvirus group.

A method of described for the simultaneous radioimmunoassay (RIA) for antibody to members of the human herpesvirus group. The RIA is compared with some of the conventional serologic techniques used to quantitate antibody to these viruses (Epstein-Barr virus, cytomegalovirus, herpesvirus type 1 and varicella-zoster virus). Color-coded beads, each coated with the antigens of a different herpesvirus, were similtaneously placed in a well which contained a human serum to be assayed for antibody to each of these 4 viruses. The results of this test were compared with the results obtained when the serum was assayed for antibody to the 4 viruses in 4 separate tests. We conclude that the antigen-antibody reactions do not significantly interfere with each other when a serum is assayed for antibody to the 4 viruses simultaneously. A comparison of the RIA with conventional serologic techniques shows excellent correlation in the antibody titers obtained. Features of the solid-phase RIA allow significant savings of time, reagents and space, and thus make it feasible for the small laboratory to screen large numbers of sera for antibody to a variety of antigens.

Antibodies, Viral↗
PubMed1979

Use of protein A-treated sera in unmasking herpes simplex virus type 1 (HSV-1) immunoglobulin A and identifying HSV-1 immunoglobulin G as the predominant neutralizing antibody.

Treatment of human sera with protein A reduced the amounts of immunoglobulin G (IgG), IgA, and IgM detected by radial immunodiffusion. This treatment also decreased the amount of herpes-specific IgG and IgM detected by radioimmunoassay, whereas it increased and even unmasked the amount of herpes-specific IgA detected. Comparison of protein A-treated sera with untreated sera indicated that herpes simplex virus type 1 IgG was responsible for more than 92 to 99% of the serum neutralizing activity.

Antibodies, Viral↗
PubMed1977

A solid phase radioimmunoassay for detection of serum autoantibodies in systemic lupus erythematosus.

Solid phase radioimmunoassay (RIA) methods for measuring autoantibodies in systemic lupus erythematosus (SLE) patients' serum were developed to improve the sensitivity and quantitative precision of these determinations. Two mechanical systems were studied: (1) acetone fixed cell monolayers in glass tubes and (2) antigen coated plastic beads. Both systems were sensitive and reproducible, giving serum dilution end-points between two and four orders of magnitude (100-10,000 times) greater than those obtained by fluorescence microscopy. The most sensitive, versatile system involves the coating of plastic beads with nuclear antigen(s), incubation overnight with sera and labelling with 125I conjugated antihuman globulin. Linear binding of this radioactive tag is obtained over a wide range of SLE serum dilutions and the slopes of the serum dilution titration curves are almost identical for all SLE patients' sera we have tested. Therefore, a standard titration curve can be constructed from the results with a positive serum, and end-point dilutions of unknown sera estimated from results obtained with a single serum dilution. Alternatively, binding ratios of unknown sera can be usefully compared at fixed dilutions with standard positive and negative sera. For example, high binding ratios (greater than 3.0) were obtained with 19/20 SLE sera and 0/20 control sera. Antigens used in these systems include crude, whole-cell lysates and lysates from purified nuclei. These RIA methods appear to provide certain advantages over existing autoantibody assay methods because they are relatively simple, sensitive, reproducible and potentially capable of measuring a variety of autoantibody specificities.

Antigens↗
PubMed1977

Radioimmunoassay procedure for quantitating bacterial antibody in human sera.

A RIA system was developed to detect antibodies in human sera against bacteria. Sonicates of Escherichia coli and Fusobacterium polymorphum were used as antigens to sensitize plastic-coated beads; antibodies to these antigens were detected with 125I-labeled antihuman globulin. Serum antibody titers against E. coli were determined by the serial dilution method; from the results the standard curve principle was applied in determining the relative amounts of antibodies against E. coli in serum samples tested at a single dilution. The coefficient of variation of the RIA procedure was less than 10%. Serum titers obtained by the RIA and indirect immunofluorescence test were compared; RIA was more sensitive, quantitative and objective. Absorption studies, using E. coli and F. polymorphum absorbentes against E. coli and F. polymorphum. This RIA procedure offers a combination of desirable advantages; it is sensitive, specific, objective, quantitative, and easy to perform.

Antibodies, Bacterial↗
PubMed1977

Magnetic transfer devices for use in solid-phase radioimmunoassays and enzyme-linked immunosorbent assays.

A method was developed for the simultaneous transfer of large numbers of solid-phase adsorbents in radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA). Specially coated ferromagnetic spheres (beads) were used as the solid phase. These beads were transferred from a reaction mixture through a rinse bath to another reaction mixture by magnetic probes. The quality of results obtained with this new methodology compared favorably with that obtained when solid-phase adsorbents were handled individually. The magnetic transfer system provided a high degree of mechanization, thus permitting many more tests to be performed at one time, under almost identical conditions. Certain mechanical features of the test and the micro scale of the reactions provided substantial economy in time and consumption of valuable reagents. The sensitivities of the RIA and ELISA for detection of viral antibody were about the same. An important advantage in using magnetic devices for transfer of beads is that the immune and enzyme-substrate reactions can be started and stopped instantly in either system.

Antibodies, Viral↗
PubMed1976

An approach to the serodiagnosis of human lung cancer. Cell culture lines reactive as antigens with tumor patients' sera.

A solid-phase radioimmunoassay technique was used to quantitate antigen-antibody reactions between various human cell lines and lung cancer patients' sera. Four human fetal lung cell lines and four human tumor cell lines were more or less reactive as antigens. Failure to obtain exact correspondence between reactions with these cell lines indicates that more than one antigen may be required for detecting specific antibodies to the various lung tumor types. These results suggest that serum antibody detection might be a feasible approach to the immunodiagnosis of lung cancer at stages when the tumor masses are relatively small.

Antibodies, Neoplasm↗
PubMed1976

Radioimmunoassay for toxoplasmosis.

A solid-phase radioimmunoassay for toxoplasmosis has been developed, and the results show good correlation with the indirect hemagglutination test.

Hemagglutination Tests↗