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Accurate determination of the immunoglobulin (Ig) M paraprotein concentration is crucial to evaluating response in patients with Waldenström macroglobulinemia (WM). In most clinical laboratories, M-spike quantitation is performed by serum protein electrophoresis, which is the same method used to quantitate IgG and IgA paraproteins in patients with multiple myeloma (MM). However, the migration p...

Serum and intestinal secretory IgA (sIgA) were investigated in control subjects and patients with alcoholic cirrhosis of the liver. Intestinal secretions were sampled by intraluminal perfusion with a balloon catheter. Monomeric IgA and sIgA were assayed by reversed radial immunodiffusion and nephelometry after separation by Ultrogel column filtration. High levels of serum sIgA were found only i...

Various parameters of three radial immunodiffusion systems, a kinetic nephelometer and two laser nephelometers were compared in a measurement of IgG and albumin in cerebrospinal fluid. Greater precision for IgG and albumin determinations was found with two RID systems. Correlation coefficients between methods ranged from 0.71 to 0.94. The generally poor correlations of methods, combined with th...

We evaluated new, commercially available reagents for assaying apolipoproteins (apo) A-I and B by rate nephelometry (INA). Our initial linearity studies for apoA-I indicated that use of the commercial diluent resulted in incomplete immunoreactivity. Subsequent revision of the calibration line by the manufacturer compensated for this and improved the linearity for the apoA-I assay. We observed g...

Zusammenfassung: Fibronectin (Synonyma: Kälteunlösliches Globulin, j3-Kryoglobulin, Antigelatine-Faktor) ist ein Glykoprotein von Zelloberflächen. Im menschlichen Plasma sind hohe Konzentrationen an Fibronectin nachweisbar. Wegen des schwierigen und kostenintensiven Nachweises durch Radioimmunoassay sind bislang nur wenige Berichte über Fibronectinkonzentrationen im Plasma von Patienten bekannt...

Within the past decade nephelometric methods of analysis have become increasingly popular in biochemical work, so that at present a nephelometer has come to be counted an indispensable piece of apparatus in every well equipped laboratory. Nephelometry has however the serious disadvantage that, as was first pointed out by Richards and Wells,i the amount of light reflected is not strictly proport...

Pontet et al. (1) recently argued that, in contrast to polyclonal 1gM, accurate data on concentrations of monoclonal 1gM in different patients is difficult to obtain because of the dependence of the results on the technique. This statement is at variance with previously published work of De Bruijn and Klein (2, 3) who came to different conclusions. According to our findings, confirmed by Out et...

Manual and automated immunonephelometric tests (1, 2) have been developed for determination of serum prealbumin (transthyretin, PA). This methodology is more precise and rapid than radial immunodiffusion, but lipoproteins and immunoglobulins interfere with immunonephelometric methods (2,3). We describe here an immunonephelometric method for PA in serum from the newborn. We took special care to ...