Kinetics of the IgG—anti-IgG Reaction, as Evaluated by Conventional and Stopped-Flow Nephelometry

1974 ◽  
Vol 20 (8) ◽  
pp. 1071-1075 ◽  
Author(s):  
John Savory ◽  
Gregory Buffone ◽  
Richard Reich
Keyword(s):  
Polyethylene Glycol ◽  
Data Acquisition System ◽  
Lag Phase ◽  
Stopped Flow ◽  
Kinetic Measurement ◽  
Antigen Concentration ◽  
Specific Proteins ◽  
Rapid Reaction ◽  
Antigen Antibody ◽  
Kinetics Of

Abstract A stopped-flow spectrophotofluorometer equipped with a data-acquisition system was used to study the rate of formation of IgG—anti-IgG complexes by nephelometry. Light-scattering aggregates could be detected within 100 ms. Early rates ( 0-3 s) increased with antigen concentration, while rates during later stages (5-100 s) followed the same trend exhibited by the precipitin curve. Polyethylene glycol (known to exert a profound effect on antigen—antibody reactions) at a concentration of 40 g/liter affected the IgG—anti-IgG reaction as follows: there was an initial lag phase of 5-10 s and a subsequent rapid reaction over the next 20-40 s, characterized by a four-to five-fold enhancement in the amount of light scattered. Our observations demonstrate that centrifugal-analyzer techniques can be used for the kinetic measurement of specific proteins in serum.

Evaluation of Kinetic Light Scattering as an Approach to the Measurement of Specific Proteins with the Centrifugal Analyzer. II. Theoretical Considerations

1975 ◽  
Vol 21 (12) ◽  
pp. 1735-1746 ◽  
Author(s):  
Gregory J Buffone ◽  
John Savory ◽  
J Hermans
Keyword(s):  
Light Scattering ◽  
Reaction Rate ◽  
Analytical Methodology ◽  
Complex Dimension ◽  
Specific Proteins ◽  
Antibody Complex ◽  
Antigen Antibody ◽  
Theoretical Considerations ◽  
Kinetics Of ◽  
Insight Into

Abstract Development of centrifugal analyzers capable of making light-scattering measurements has prompted the investigation of the application of this type of instrumentation to the measurement of specific proteins. Investigation of antigen/antibody complex dimension and the kinetics of the IgG/anti-IgG reaction as followed by light scattering are examined in relation to improved analytical methodology. The effect of nonspecific protein on the reaction rate has been investigated for IgM, and data are presented that provide insight into the mechanism of the effect of periodic mixing.

scholarly journals STUDIES ON THE MECHANISMS OF HYPERSENSITIVITY PHENOMENA

1964 ◽  
Vol 120 (4) ◽  
pp. 507-530 ◽  
Author(s):  
Lawrence M. Lichtenstein ◽  
Abraham G. Osler
Keyword(s):  
Histamine Release ◽  
Divalent Cations ◽  
Lag Phase ◽  
Antigen Concentration ◽  
Release Process ◽  
Viable Cells ◽  
Cellular Sensitivity ◽  
Before And After ◽  
Release Histamine ◽  
Kinetics Of

Human leukocytes, isolated from the blood of ragweed-sensitive donors, release histamine upon reaction with a purified protein antigen derived from this pollen. The release process has been studied with washed cells suspended in a defined, serum-free medium. Physiologic levels of pH, ionic strength, and temperature, as well as both calcium and magnesium, are required for optimal cellular reactivity. The level of cellular sensitivity of approximately 200 ragweed-sensitive donors has been ascertained, and the kinetics of the release process studied. The rate of histamine release is a function of antigen concentration, but even with a large excess of this reagent it is impossible to abolish a lag phase. Chelation of the divalent cations or a decrease in the reaction temperature may be utilized to stop the reaction. These measures are effective both before and after the initiation of histamine release. Diminished cellular reactivity (desensitization) has been achieved by several procedures. These have in common the addition of antigen to cells in an environment deficient in but a single respect, followed by a restoration of optimal conditions. The significance of these data has been discussed and it has been proposed that immunologically induced histamine release is an active, enzymatically mediated process which occurs as a multistep response of viable cells to a specific antigenic stimulus.

Kinetics of the Antigen: Antibody Reaction

1983 ◽  
Vol 20 (4) ◽  
pp. 224-226 ◽  
Author(s):  
I Deverill ◽  
R J Lock
Keyword(s):  
Light Scattering ◽  
Photon Correlation Spectroscopy ◽  
Fluid Phase ◽  
Correlation Spectroscopy ◽  
Photon Correlation ◽  
Specific Proteins ◽  
Antibody Reaction ◽  
Scatter Intensity ◽  
Antigen Antibody ◽  
Kinetics Of

Many techniques for the estimation of specific proteins measure light scattered by, or the turbidity of, suspensions of antigen:antibody aggregates formed in fluid-phase reactions. Although the shapes of reaction curves obtained are well documented,1 2 interpretation of the data in relation to the laws of light scattering and the mechanism of the antigen:antibody reaction are poorly described in the literature. Using photon correlation spectroscopy it has been shown that antigen:antibody complexes continue to grow in size even when no further increases in scatter intensity or turbidity are apparent.

Prothrombin Evaluation as Obtained by Kinetics Studies of Antigen-Antibody Reaction in a Laser Nephelometer

1984 ◽  
Vol 52 (01) ◽  
pp. 015-018 ◽  
Author(s):  
A Girolami ◽  
A Sticchi ◽  
R Melizzi ◽  
L Saggin ◽  
G Ruzza
Keyword(s):  
Liver Cirrhosis ◽  
Cirrhotic Patient ◽  
Maximum Rate ◽  
Serum Proteins ◽  
Clotting Factors ◽  
Kinetics Studies ◽  
Maximum Value ◽  
Time Required ◽  
Antigen Antibody ◽  
Kinetics Of

SummaryLaser nephelometry is a technique which allows the evaluation of the concentration of several serum proteins and clotting factors. By means of this technique it is also possible to study the kinetics of the reaction between antigen and antibody. We studied the kinetics of the reaction between prothrombin and an antiprothrombin antiserum using several prothrombins namely: Prothrombin Padua, prothrombin Molise, which are two congenital dysprothrombinemias, cirrhotic, coumarin or normal prothrombins. Different behaviors in the kinetics of the reactions were shown even when the concentration of prothrombins was about the same in all plasma tested. These differences were analyzed by means of a computer (Apple II 48 RAM) programmed to solve four unknown equations (Rodbard’s equation). From the data so obtained one can see that when voltages at the beginning and at the end of the reaction are in all cases about the same, a clear difference in the time required to reach half the maximum value of the voltage can still be demonstrated. This parameter, which is expressed in minutes, is longer in coumarin and prothrombin Molise than in controls. On the contrary it is shorter in prothrombin Padua and has about the same value of controls in the cirrhotic patient. Moreover the time at which the maximum rate is obtained is longer in coumarin and prothrombin Molise than in controls and shorter in liver cirrhosis and prothrombin Padua. In conclusion data obtained show that coumarin prothrombin behaves in a different way from cirrhotic prothrombin and also that there is a different behaviour between the two congenital dysprothrombinemias.

scholarly journals Kinetics of tau aggregation reveals patient specific tau characteristics among Alzheimer's cases

2021 ◽  
Author(s):  
Tarun V Kamath ◽  
Naomi Klickstein ◽  
Caitlin Commins ◽  
Analiese R Fernandes ◽  
Derek H Oakley ◽  
...  
Keyword(s):  
Growth Phase ◽  
Tau Proteins ◽  
Patient Specific ◽  
Lag Phase ◽  
Plateau Phase ◽  
Kinetic Assay ◽  
Cellular Processes ◽  
Morphological Differences ◽  
Tau Aggregation ◽  
Kinetics Of

Abstract The accumulation of tau aggregates throughout the human brain is the hallmark of a number of neurodegenerative conditions classified as tauopathies. Increasing evidence shows that tau aggregation occurs in a “prion-like” manner, in which a small amount of misfolded tau protein can induce other, naïve tau proteins to aggregate. Tau aggregates have been found to differ structurally among different tauopathies. Recently, however, we have suggested that tau oligomeric species may differ biochemically among individual patients with sporadic Alzheimer disease, and have also showed that the bioactivity of the tau species, measured using a cell-based bioassay, also varied among individuals. Here, we adopted a live-cell imaging approach to the standard cell-based bioassay to explore further whether the kinetics of aggregation also differentiated these patients. We found that aggregation can be observed to follow a consistent pattern in all cases, with a lag phase, a growth phase, and a plateau phase, which each provide quantitative parameters by which we characterize aggregation kinetics. The length of the lag phase and magnitude of the plateau phase are both dependent upon the concentration of seeding-competent tau, the relative enrichment of which differs among patients. The slope of the growth phase correlates with morphological differences in the tau aggregates, which may be reflective of underlying structural differences. This kinetic assay confirms and refines the concept of heterogeneity in the characteristics of tau proteopathic seeds among individuals with Alzheimer’s disease and is a method by which future studies may characterize longitudinal changes in tau aggregation and the cellular processes which may influence these changes.

Stopped-flow and Brownian dynamics studies of electrostatic effects in the kinetics of binding of 7-methyl-GpppG to the protein eIF4E

2000 ◽  
Vol 29 (7) ◽  
pp. 487-498 ◽  
Author(s):  
E. Błachut-Okrasińska ◽  
E. Bojarska ◽  
A. Niedźwiecka ◽  
L. Chlebicka ◽  
E. Darżynkiewicz ◽  
...  
Keyword(s):  
Brownian Dynamics ◽  
Stopped Flow ◽  
Electrostatic Effects ◽  
Kinetics Of

The mechanism of the oxidation of thiocyanate ion by peroxomonosulphate in aqueous solution. II. Kinetics of the reaction

1966 ◽  
Vol 19 (8) ◽  
pp. 1365 ◽  
Author(s):  
RH Smith ◽  
IR Wilson
Keyword(s):  
Aqueous Solution ◽  
Initial Rate ◽  
Stopped Flow ◽  
Thiocyanate Ion ◽  
First Order ◽  
Conductance Method ◽  
Rate Of Reaction ◽  
Kinetics Of

Initial rates of reaction for the above oxidation have been measured by a stopped-flow conductance method. Between pH 2 and 3.6, the initial rate of reaction, R, is given by the expression R{[HSO5-]+[SCN-]} = {kb+kc[H+]}[HSO5-]0[SCN-]20+ka[H+]-1[HSO5]20[SCN-]0 As pH increases, there is a transition to a pH-independent rate, first order in each thiocyanate and peroxomonosulphate concentrations.

Effect of Hypertonic Sucrose Upon the Immune Bactericidal Reaction

1970 ◽  
Vol 1 (1) ◽  
pp. 51-55
Author(s):  
Louis H. Muschel ◽  
Linda J. Larsen
Keyword(s):  
Cell Death ◽  
Cell Wall ◽  
Enzymatic Reaction ◽  
Inhibitory Effect ◽  
Lag Phase ◽  
Inner Membrane ◽  
Bactericidal Antibody ◽  
Kinetics Of ◽  
Free Serum ◽  
Supporting Structures

This study was performed to determine the mechanism whereby hypertonic sucrose inhibits the immune bactericidal reaction. Other investigators had postulated that the initial attack of complement (C) on the cell wall was followed with lysozyme-containing whole serum by an enzymatic reaction upon the peptidoglycan substrate resulting in cell death. In the absence of serum lysozyme, secondary lethal changes might occur from damage to the cell's inner membrane as a result of osmotic forces in the presence of a defective cell wall. Hypertonic sucrose giving rise to plasmolysis and protection of the inner membrane was presumed to differentially inhibit the immune response mediated by lysozyme-free serum. The experimental results observed in this investigation have indicated, however, that the inhibitory effect of sucrose upon the bactericidal reaction may be explained simply by its anticomplementary effect and not by any effect on the bacterial cell. This view was supported by the following observations: (i) the comparability of the inhibitory effect of sucrose upon the immune hemolytic and bactericidal reactions, (ii) the comparable percentage loss in bactericidal activity of whole serum and lysozyme-free serum resulting from hypertonic sucrose, (iii) bactericidal antibody titrations were relatively unaffected and C titrations markedly inhibited by sucrose, (iv) the inhibitory effect of sucrose on the bactericidal reaction was unaffected by prior growth of the organism in the presence of sucrose, (v) the kinetics of the bactericidal reactivity of lysozyme-free serum in hypertonic sucrose, compared with whole serum, did not reveal a prolonged lag phase with lysozyme-free serum, but simply diminished reactivity at all times. These observations are compatible with the view that the C attack upon the outer surface of gram-negative bacteria, which plays a part in the cell's permeability control, may account for cell death. In this regard, the immune bactericidal reaction is quite comparable to the lysis of red cells or nucleated cells by C despite the lack of overt lysis in bacteria, probably because of their underlying supporting structures.

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