scholarly journals THE FIXATION OF COMPLEMENT AND THE ACTIVATED FIRST COMPONENT (C1) OF COMPLEMENT BY COMPLEXES FORMED BETWEEN ANTIBODY AND DIVALENT HAPTEN

1970 ◽  
Vol 131 (4) ◽  
pp. 783-802 ◽  
Author(s):  
N. E. Hyslop ◽  
R. R. Dourmashkin ◽  
N. M. Green ◽  
R. R. Porter

Hapten-antibody complexes prepared at equivalence with the bivalent hapten bis-DNP-octamethylene-diamine and purified rabbit anti-DNP antibody were fractionated by Sepharose gel-filtration and the fractions examined by electron microscopy. Individual fractions were tested for whole-complement fixation and C1 fixation. Dimer forms did not show this type of biological activity, while fractions containing tetramers and larger polymers exhibited both C and C1 fixation, which could be inhibited by prior exposure of the complexes to the univalent hapten epsilon-DNP-caproic acid. The dose-response result indicated that the C-fixation observed was not due to interpolymeric cooperative effects. It was concluded that in the generation of biological activity by soluble antigen-antibody complexes made with complement-fixing antibody, quaternary structural changes following specific combination with antigen may be as important as any tertiary structural alterations that occur in the individual immunoglobulin molecule.

1959 ◽  
Vol 109 (2) ◽  
pp. 127-143 ◽  
Author(s):  
Kimishige Ishizaka ◽  
Teruko Ishizaka ◽  
Dan H. Campbell

Soluble BSA-anti-BSA complexes, formed in antigen excess, give immediate skin reactions in normal guinea pigs. The mechanism of the reaction is not that of passive or reversed passive anaphylaxis. The complex itself is toxic. Skin activity of the complex depends on its composition. It has become obvious that the complex composed of two antigen molecules and one antibody molecule, (Ag2Ab), does not have the activity, whereas, Ag3Ab2 and more complicated complexes do. The role of complement as well as speculation on the structural changes of antibody-antigen complexes is presented.


1975 ◽  
Vol 34 (03) ◽  
pp. 740-747 ◽  
Author(s):  
C. R. M Prentice ◽  
C. D Forbes ◽  
Sandra Morrice ◽  
A. D McLaren

SummaryBetting odds for possible carriers of haemophilia have been calculated using data derived from normal and known carrier populations. For each possible carrier the concentration of factor VIII-related antigen and factor VIII biological activity was measured and used to determine the probability of the individual being a carrier. The calculations indicated that, of the 32 possible carriers, 11 were likely to be normal (odds of more than 5:1) while 11 were likely to be haemophilia carriers (again odds of more than 5:1).


1960 ◽  
Vol 4 (01) ◽  
pp. 031-044
Author(s):  
George Y. Shinowara ◽  
E. Mary Ruth

SummaryFour primary fractions comprising at least 97 per cent of the plasma proteins have been critically appraised for evidence of denaturation arising from a low temperature—low ionic strength fractionation system. The results in addition to those referable to the recovery of mass and biological activity include the following: The high solubilities of these fractions at pH 7.3 and low ionic strengths; the compatibility of the electrophoretic and ultracentrifugal data of the individual fractions with those of the original plasma; and the recovery of hemoglobin, not hematin, in fraction III obtained from specimens contaminated with this pigment. However, the most significant evidence for minimum alterations of native proteins was that the S20, w and the electrophoretic mobility data on the physically recombined fractions were identical to those found on whole plasma.The fractionation procedure examined here quantitatively isolates fibrinogen, prothrombin and antithrombin in primary fractions. Results have been obtained demonstrating its significance in other biological systems. These include the following: The finding of 5 S20, w classes in the 4 primary fractions; the occurrence of more than 90 per cent of the plasma gamma globulins in fraction III; the 98 per cent pure albumin in fraction IV; and, finally, the high concentration of beta lipoproteins in fraction II.


1969 ◽  
Vol 62 (1_Suppl) ◽  
pp. S13-S30 ◽  
Author(s):  
W. R. Butt

ABSTRACT Several chemical differences between FSH, LH and HCG have been reported: thus LH and HCG are richer in proline than FSH and FSH and HCG contain more N-acetyl neuraminic acid than LH. Sub-units of LH are formed by treatment with urea, guanidine or acid. HCG also may contain two sub-units. The sub-units from LH are biologically inert but retain their immunological activity: biological activity is restored when the sub-units are incubated together. There is much evidence from chemical and enzymic reactions that antigenic groups are distinct from those parts of the molecule essential for biological activity. N-acetyl neuraminic acid and probably other carbohydrates in FSH and HCG are not involved in immunological activity but are necessary for biological activity. Histidine, methionine and possibly cysteine appear to be essential for biological but not immunological activity of FSH, while tryptophan and possibly tyrosine are not essential for either. A few highly specific antisera to gonadotrophins have been prepared in rabbits and guinea pigs to crude antigens: there is no evidence that purified antigens are more likely to produce specific antisera. Differences in the immunological reactivities of urinary compared with pituitary gonadotrophins have been observed both by radioimmunoassay and by the complement fixation technique. The latter may be particularly useful for detecting structural differences in the hormones.


Entropy ◽  
2021 ◽  
Vol 23 (3) ◽  
pp. 290
Author(s):  
Maxim Pyzh ◽  
Kevin Keiler ◽  
Simeon I. Mistakidis ◽  
Peter Schmelcher

We address the interplay of few lattice trapped bosons interacting with an impurity atom in a box potential. For the ground state, a classification is performed based on the fidelity allowing to quantify the susceptibility of the composite system to structural changes due to the intercomponent coupling. We analyze the overall response at the many-body level and contrast it to the single-particle level. By inspecting different entropy measures we capture the degree of entanglement and intraspecies correlations for a wide range of intra- and intercomponent interactions and lattice depths. We also spatially resolve the imprint of the entanglement on the one- and two-body density distributions showcasing that it accelerates the phase separation process or acts against spatial localization for repulsive and attractive intercomponent interactions, respectively. The many-body effects on the tunneling dynamics of the individual components, resulting from their counterflow, are also discussed. The tunneling period of the impurity is very sensitive to the value of the impurity-medium coupling due to its effective dressing by the few-body medium. Our work provides implications for engineering localized structures in correlated impurity settings using species selective optical potentials.


1941 ◽  
Vol 73 (5) ◽  
pp. 581-599 ◽  
Author(s):  
Edwin H. Lennette ◽  
Frank L. Horsfall

Influenza complement fixation tests designed for use with ferret serum are described. Complement-fixing antigens derived from influenza ferret lungs were unsatisfactory due to their low content of soluble antigen; those prepared from mouse lungs or developing chick embryo membranes proved to be better antigenically and were reliable when the various reagents in the test were properly adjusted to eliminate non-specific fixation of complement. The results of cross complement fixation tests indicated that the soluble antigens of the PR8 and W.S. strains of influenza A virus were closely similar, if not identical. They indicated also that the soluble antigen of swine virus possessed components present in the antigens of the human strains of virus.


2016 ◽  
Vol 72 (7) ◽  
pp. 892-903 ◽  
Author(s):  
Steven Dajnowicz ◽  
Sean Seaver ◽  
B. Leif Hanson ◽  
S. Zoë Fisher ◽  
Paul Langan ◽  
...  

Neutron crystallography provides direct visual evidence of the atomic positions of deuterium-exchanged H atoms, enabling the accurate determination of the protonation/deuteration state of hydrated biomolecules. Comparison of two neutron structures of hemoglobins, human deoxyhemoglobin (T state) and equine cyanomethemoglobin (R state), offers a direct observation of histidine residues that are likely to contribute to the Bohr effect. Previous studies have shown that the T-state N-terminal and C-terminal salt bridges appear to have a partial instead of a primary overall contribution. Four conserved histidine residues [αHis72(EF1), αHis103(G10), αHis89(FG1), αHis112(G19) and βHis97(FG4)] can become protonated/deuterated from the R to the T state, while two histidine residues [αHis20(B1) and βHis117(G19)] can lose a proton/deuteron. αHis103(G10), located in the α1:β1dimer interface, appears to be a Bohr group that undergoes structural changes: in the R state it is singly protonated/deuterated and hydrogen-bonded through a water network to βAsn108(G10) and in the T state it is doubly protonated/deuterated with the network uncoupled. The very long-term H/D exchange of the amide protons identifies regions that are accessible to exchange as well as regions that are impermeable to exchange. The liganded relaxed state (R state) has comparable levels of exchange (17.1% non-exchanged) compared with the deoxy tense state (T state; 11.8% non-exchanged). Interestingly, the regions of non-exchanged protons shift from the tetramer interfaces in the T-state interface (α1:β2and α2:β1) to the cores of the individual monomers and to the dimer interfaces (α1:β1and α2:β2) in the R state. The comparison of regions of stability in the two states allows a visualization of the conservation of fold energy necessary for ligand binding and release.


1971 ◽  
Vol 17 (7) ◽  
pp. 993-1000 ◽  
Author(s):  
A. E. Kelen ◽  
A. E. Hathaway ◽  
D. A. McLeod

A simple and practical method is presented for demonstrating the presence of the Australia/SH antigen and its corresponding antibody in serum specimens, both qualitatively and quantitatively. The method is based on the electronmicroscopic visualization of characteristic aggregates of antigen–antibody complexes formed in the mixture of a serum specimen and the appropriate Australia/SH detector reagent. It involves the use of a microtechnique requiring minute amounts of reagents and provides, as a result of diffusion and filtration through agar gel, partially purified and concentrated preparations, ready for electronmicroscopic examination in less than an hour. The method is highly specific and yields reproducible results. Its sensitivity was found to be greater than that of the crossover electrophoresis test and closely approximates that of the complement fixation test, with the added advantage of not being affected by the "prozone phenomenon." The method can be recommended for use in laboratories equipped with electronmicroscopic facilities to establish a differential diagnosis of viral hepatitis cases, perform rapid screening of blood samples (blood products) for the presence of Australia/SH antigen, and clarify equivocal results obtained by other methods. It is expected that the agar–diffusion–filtration technique will also prove useful, in general, for enhancing the chances of detecting virus particles in suspensions of relatively low virus concentrations.


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