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R F Ritchie

Publications and source records attributed to R F Ritchie.

At least 19 recordsLinked to original sources
PubMed1992

A flexible, efficient, checkerboard immunoblot system for the detection and semiquantitation of specific antinuclear antibodies.

In this paper an uncomplicated method for the simultaneous detection and semiquantitation of 11 of the 12 commonly studied antinuclear antibodies (ANA) in a single run is described. This new application of checkerboard immunoblotting (CBIB) is based upon available technology and employs purified antigens which can be either purchased or produced in-house. CBIB requires no electronic instrument, can be formatted to meet the needs of the user, is rapidly performed, and has acceptable labor and materials costs. Data on the use of the method to examine available reference antisera is presented. CBIB has also proven practical for the clinical study of 18 sera, at two dilutions per membrane, for each set of specific antinuclear antibodies, also at two or more dilutions.

Antibodies, Antinuclear↗
PubMed1991

An improved method for determining high molecular weights by protein immunoblotting: application to apolipoprotein(a) phenotyping.

The determination of very high molecular weights (greater than 500 kd) by protein immunoblotting is limited by a lack of commercially available molecular weight standards in that range. We have therefore investigated the use of the human haptoglobin 2-2 phenotype polymeric series as a high molecular weight standard curve. Using pre-electrophoresed 3-12% SDS polyacrylamide gradient gels, non-dissociated haptoglobin 2-2 serum was separated, transferred and probed with anti-human haptoglobin. We were able to visualize up to 13 bands, with a theoretical molecular weight range of 171.9-859.5 kd, in non-dissociated haptoglobin 2-2 serum. Molecular weights up to 584 kd were confirmed by comparison with available standards. The method was then applied to the determination of apolipoprotein(a) [apo(a)] phenotype molecular weights. Precision of the method was excellent, with intra-run CVs of less than 2.9% and inter-run CVs of less than 3.2% for apo(a) molecular weight. This method of molecular weight calibration is applicable to the characterization of any high molecular weight protein that can be successfully electrophoresed, transferred and visualized.

Apolipoproteins A↗
PubMed1991

International Federation of Clinical Chemistry standardization project for measurements of apolipoproteins A-I and B.

To minimize differences in apolipoprotein measurements among laboratories and methods, a standardization program involving common suitable reference material is needed. The Committee on Apolipoproteins of the International Federation of Clinical Chemistry initiated a collaborative study for the standardization of test systems for measuring apolipoproteins (apo) A-I and B, with 25 company laboratories and three research laboratories involved in apolipoprotein analysis to: (a) evaluate calibration differences among the test systems; (b) evaluate whether comparability of the data can be achieved with the use of frozen serum pools to recalibrate the different systems; and (c) evaluate and select suitable candidate reference material. We used 26 test systems for apo A-I and 28 for apo B. Relatively modest differences were found in calibration for apo A-I, but very wide differences were observed for apo B methods. After uniform calibration, the overall among-laboratory CV for apo B decreased from 19% to 6%. Three lyophilized serum preparations for apo A-I and three liquid-stabilized serum preparations for apo B were selected for further evaluation as candidate international reference materials.

Apolipoprotein A-I↗
PubMed1977

Improved electroimmunoassay of factor VIII-related antigen.

Factor VIII-related antigen migrates poorly into gel during electrophoresis in agarose, probably in major part because of the relatively high sulfate content of the commonly used agars. A recently available low-sulfate residue agar, substituted for standard agar preparations in electroimmunoassay, allows Factor VIII antigen to travel more rapidly, producing "rockets" that are well defined and easily measured, making the assay easier and more reliable.

Antigens↗
PubMed1976

Immunofixation. III. Application to the study of monoclonal proteins.

We have shown how immunofixation can be successfully used to study proteins exhibiting electrophoretic polymorphism. An analogous situation is seen in the disorders of the immune system that result in the production of variable quantitites of homogeneous immunoglobulins. Immunoelectrophroesis has been heavily used--sometimes unsuccessfully because of poor resolution--to study these materials. The appearance of a monoclonal immunoglobulin band is identical in both immunofixation and standard gel electrophoresis, a feature that allows unambiguous identification of a protein as to its heavy-chain class and light-chain type. Because antigen and antibody are placed in contact almost immediately after electrophoresis, interfering diffusion does not occur and even extremely small bands can be demonstrated and characterized.

Antibodies, Anti-Idiotypic↗
PubMed1976

Immunofixation. I. General principles and application to agarose gel electrophoresis.

Immunofixation offers the worker an economical means of physically locating a protein in an electrophoretic strip and is ideally suited to forensic medicine, genetic studies, or research. The method is as simple and economical as the commonly used one- or two-dimensional immunoelectrophoresis, yet yields considerably more information.

Blood Protein Electrophoresis↗