Quantitative precipitin

FlG. 9.—Quantitative Precipitin Curves of Mouse Myeloma Serum J558 with Various Dextrans. [Reprinted, with permission, from A. Lundblad, R. Steller, E. A. Rabat, J. W. Hirst, M. C. Weigort, and M. Cohn, Immunochemistry, 9,535-543 (1972), Pergamon Press.]... 

Figure 5. Quantitative precipitin curves of fractions from Lea substance N-l with anti-I sera Ma (A), Step (B), with type XIV antipneumococcal horse serum (C) and with goat anti-Lea (D).

Quantitative precipitin tests were performed as described.73 The amounts of precipitates obtained at the various concentrations were measured by the protein phenol method.74 The inhibition values are recorded in Table I. These inhibition data show that the precipitin reaction between the tetrahet-eropolysaccharide and the anti-GlcA antibodies is strongly inhibited by d-glucuronic acid, but with the exception of galacturonic acid none of the other carbohydrates were inhibitory. The data in the table also show that the carbohydrates tested did not inhibit the precipitin reaction between the polysaccharide and anti-GlcA-Rha antibodies. The monosaccharides alone cannot completely fit the active site of this antibody to give a precipitin test. 

Turbidimetry indicated that precipitate formation depended on the concentration of the protein as well as on that of the polysaccharide, the time-period of incubation, and the ratio of protein to polysaccharide.121,359,360 Precipitin curves determined turbidimetrically differed from those determined by analysis of precipitated nitrogen.360 For these reasons, early turbidimetric studies conducted on crude (rather than purified) con A are difficult to interpret. The quantitative precipitin method, wherein increasing amounts of polysaccharide or glycoprotein are added to standard aliquots of con A, and the resulting precipitate is washed, and analyzed for nitrogen, is now considered the method of choice for studying protein-polysaccharide interaction.170,320... 

Fig. 4.—Quantitative, Precipitin Curve of Dextran B-1355-S with Con A.309 [The total amount of dextran in the precipitate is also illustrated. Con A, 42 tg of nitrogen. (Reproduced by permission of the Journal of Biological Chemistry.)]...

Fig. 6.—Quantitative, Precipitin Curves of Rat-liver Glycogen with Con A. (O, Potassium hydroxide-extracted glycogen A, trichloroacetic acid-extracted glycogen , water-extracted glycogen. Con A, 48 /xg of nitrogen. After Ref. 369.)...

G. Schiffman, E. A. Kabat, and W. Thompson, Biochemistry 3, 113 (1964). losa Solubility refers to the effects of carrying out the quantitative precipitin assays with the same amounts of antigen and antibody but varying the total volume with saline. 

Ninhydrin Procedure for Quantitative Precipitin and Quantitative Inhibition Determinations ... 

Fig. 5. Quantitative precipitin reaction between crystalline hen egg albumin (Ea) and rabbit antibody (Ab) to crystalline hen egg albumin. From Heidelberger and Kendall. ...

For some purposes, one s primary interest may not be in the quantitative precipitin curves as such, but one may wish merely to determine the... 

Determinations of antigen by the quantitative precipitin method were used routinely for many years in some institutions for the estimation of IgG in human cerebrospinal fluid, increases in cerebrospinal fluid IgG being found in multiple sclerosis and in neurosyphilis.In recent... 

Fig. 6. Quantitative precipitin curves of mouse myeloma proteins with various dextrans. From Cisar et al. ...

Structural Insights from Quantitative Precipitin Inhibition Assays... 

Optimal precipitation requires application of the well known principles of quantitative precipitin tests. In general these involve use of an ionic strength approximating 0.15, pH between 6.5 and 8.5, temperature between 0° and 37°, and sufficient time to ensure that the reaction reaches equilibrium. In addition, the second antibody must be present in sufficient but not excessive amounts in order to ensure maximal precipitation of the nonimmune y-globulin (and thereby the primary antibody). 

Results from Butler et al. (1978). Values for the ElA are based on a standard rat-anti DNP pool ( = 0.82 mg/ml) which was measured by the quantitative precipitin assay. Amplified ElA is an ElA test in which immunologically conjugated enzyme is used (see Section 14.2.1.3). 

The quantitative precipitin analysis of antibody-antigen interactions as introduced... 

Fig. 18 (68). Comparison of immunological properties of human cuprein isolated from erythrocytes (O), liver (%i), and brain(B). Quantitative precipitin reactions of rabbit antibody to erythrocuprein were performed...

Figure 3. Quantitative precipitin curves of (O) anti-ACE, anti-ACWC, and...

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