CHEMISTRY OF GONADOTROPHINS IN RELATION TO THEIR ANTIGENIC PROPERTIES

1969 ◽  
Vol 62 (1_Suppl) ◽  
pp. S13-S30 ◽  
Author(s):  
W. R. Butt
Keyword(s):  
Biological Activity ◽  
Guinea Pigs ◽  
Complement Fixation ◽  
Neuraminic Acid ◽  
Fixation Technique ◽  
Immunological Activity ◽  
Antigenic Properties ◽  
Specific Antisera ◽  
Structural Differences

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.

EFFECT OF OXIDATION ON BIOLOGICAL AND IMMUNOLOGICAL ACTIVITY OF PORCINE PARATHYROID HORMONE

1974 ◽  
Vol 63 (1) ◽  
pp. 117-124 ◽  
Author(s):  
J. L. H. O'RIORDAN ◽  
J. S. WOODHEAD ◽  
G. N. HENDY ◽  
J. A. PARSONS ◽  
C. J. ROBINSON ◽  
...  
Keyword(s):  
Biological Activity ◽  
Parathyroid Hormone ◽  
Cysteine Oxidation ◽  
Subsequent Reduction ◽  
Immunological Activity ◽  
Parathyroid Hormones ◽  
Methionine Residue

SUMMARY The presence of a single methionine in porcine parathyroid hormone, at position 8, permitted assessment of the role of this residue separate from the second methionine residue found at position 18 of bovine and human parathyroid hormones. Oxidation of the solitary methionine of porcine parathyroid hormone to the sulphoxide destroyed biological activity, but this was restored by subsequent reduction with cysteine. Oxidation of the hormone did not, however, affect its immunological activity; therefore, oxidation of the hormone may bring about dissociation of biological and immunological activity.

ANTIGONADOTROPHIC PROFILE OF ANTISERA AGAINST HUMAN GONADOTROPHIN PREPARATIONS

1971 ◽  
Vol 67 (2) ◽  
pp. 262-276 ◽  
Author(s):  
P. Petrusz ◽  
C. Robyn ◽  
E. Diczfalusy
Keyword(s):  
Biological Activity ◽  
Luteinizing Hormone ◽  
Total Dose ◽  
Follicle Stimulating Hormone ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Immunological Activity ◽  
Human Menopausal Gonadotrophin ◽  
Stimulating Hormone

ABSTRACT Forty-two antisera were prepared in rabbits against human chorionic gonadotrophin (HCG), human hypophysial gonadotrophin (HHG), human urinary luteinizing hormone (LH) and human menopausal gonadotrophin (HMG) preparations. The gonadotrophic profiles of the antigens were previously characterized by bioassay, immunoassay and bioimmunoassay methods. The 25 most potent antisera were tested in statistically valid bioassays for their HCG and follicle stimulating hormone (FSH) neutralizing activities as well as for their neutralizing potencies against the FSH-like activity present in HCG preparations. The anti-HCG/anti-FSH ratios of the anti-HCG sera tested varied between 6.2 and > 254, while those of the anti-HHG, anti-LH and anti-HMG sera were close to 2. It was found that the total dose of immunological activity (anti-HCG neutralizing and anti-FSH neutralizing potency) rather than that of the biological activity administered to the rabbits was decisive for obtaining antisera with high anti-HCG and anti-FSH titers. Immunization with a highly purified HCG preparation (> 17 000 IU/mg) resulted in antisera exhibiting lower anti-HCG/anti-FSH ratios than did immunization with partially purified preparations. A highly purified urinary LH preparation which did not contain any detectable FSH activity gave rise to antisera exhibiting anti-HCG/anti-FSH ratios of approximately 2.0. These highly purified HCG and LH preparations were shown previously to possess high anti-FSH neutralizing potencies (Petrusz et al. 1971b). Booster injections did not change significantly the quality or the titer of the antigonadotrophic sera studied. The HCG neutralizing potency of anti-HCG sera was approximately 3 times higher when assayed against a highly purified HCG preparation (> 17 000 IU/mg) as compared to potency estimates obtained against the laboratory standard of HCG (about 2000 IU/mg). It is suggested that consideration should be given to the establishment of standard preparations of antigonadotrophic sera. It is concluded that bioimmunoassays are more suitably than conventional bioassay methods for the assessment of the antigenic purity of human gonadotrophin preparations.

scholarly journals A SOLUBLE ANTIGEN OF LYMPHOCYTIC CHORIOMENINGITIS

1940 ◽  
Vol 71 (1) ◽  
pp. 43-53 ◽  
Author(s):  
J. E. Smadel ◽  
M. J. Wall ◽  
R. D. Baird
Keyword(s):  
Guinea Pigs ◽  
Complement Fixation ◽  
Lymphocytic Choriomeningitis ◽  
Immune Serum ◽  
Splenic Tissue ◽  
The Other ◽  
Soluble Antigen ◽  
Precipitin Reaction ◽  
Other Hand ◽  
Protein Nature

The soluble antigen of lymphocytic choriomeningitis which is readily separable from the virus is a relatively stable substance and appears to be of a protein nature. A specific precipitin reaction can be demonstrated when immune serum is added to solutions of antigen which have been freed of certain serologically inactive substances. The complement-fixation and precipitation reactions which occur in the presence of immune serum and non-infectious extracts of splenic tissue obtained from guinea pigs moribund with lymphocytic choriomeningitis seem to be manifestations of union of the same soluble antigen and its antibody. On the other hand, the antisoluble substance antibodies and neutralizing substances appear to be different entities.

An Immunological Perspective on Evolutionary Relationships in Australian Frogs of the Hylid Genus Cyclorana

1985 ◽  
Vol 33 (1) ◽  
pp. 17 ◽  
Author(s):  
LR Maxson ◽  
DP Ondrula ◽  
MJ Tyler
Keyword(s):  
Complement Fixation ◽  
Species Group ◽  
Evolutionary Relationships ◽  
Species Relationships ◽  
Fixation Technique ◽  
Serum Albumins ◽  
Morphological Studies ◽  
Biochemical Analyses

Detailed morphological studies as well as recent biochemical analyses have demonstrated substantial differentiation within the widespread Australian hylid frog genus Cyclorana. To further investigate species relationships within Cyclorana, supplemental immunological studies were performed. Serum albumins of 10 species of Cyclorana and three species of the related hylid genus Litoria were compared by means of the quantitative micro-complement fixation technique. This analysis suggests that there are three Cyclorana lineages: C. maini, C. cultripes, C. brevipes and C. longipes forming one cluster, C. australis clustering with L. alboguttata, and C. platycephalus. All species of Cyclorana studied, as well as L. alboguttata, are genetically closest to, but distinct from, species in the L. aurea species-group.

STUDIES ON THE ANTIGENIC STRUCTURE OF HISTOPLASMA CAPSULATUM

1957 ◽  
Vol 3 (7) ◽  
pp. 975-985 ◽  
Author(s):  
N. A. Labzoffsky ◽  
J. B. Fischer ◽  
J. J. Hamvas
Keyword(s):  
Histoplasma Capsulatum ◽  
Complement Fixation ◽  
Antigenic Structure ◽  
Fixation Technique ◽  
Chemical Methods ◽  
Physical And Chemical

Employing physical and chemical methods eight antigenic fractions were isolated from Histoplasma capsulatum as determined by complement fixation technique. Two of the fractions were found to cross-react with coccidioidal antisera, two with coccidioidal and Blastomyces antisera, one with Blastomyces antisera, while the remaining three displayed specificity by reacting with Histoplasma antisera only. Some evidence is presented to indicate that the isolated fractions are antigenically distinct.

DIFFERENCES IN THE BIOLOGICAL AND IMMUNOLOGICAL ACTIVITIES OF HUMAN CHORIONIC GONADOTROPHIN AFTER THE REMOVAL OF SIALIC ACID BY ENZYMIC HYDROLYSIS

1967 ◽  
Vol 38 (4) ◽  
pp. 395-399 ◽  
Author(s):  
W. A. BARR ◽  
J. G. COLLEE
Keyword(s):  
Biological Activity ◽  
Sialic Acid ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Enzymic Hydrolysis ◽  
Immunological Activity ◽  
Parallel Reduction ◽  
Free Sialic Acid

SUMMARY Incubation of a partially purified preparation of human chorionic gonadotrophin (HCG) with neuraminidase resulted in release of free sialic acid from the substrate. The biological activity of the HCG was considerably reduced after incubation with the enzyme, but a parallel reduction in immunological activity was not observed.

THE DEVELOPMENT OF A RADIOIMMUNOASSAY FOR OXYTOCIN: SENSITIVITY OF THE ASSAY IN AQUEOUS BUFFER SOLUTION, SPECIFICITY AND THE DISSOCIATION OF IMMUNOLOGICAL AND BIOLOGICAL ACTIVITY

1970 ◽  
Vol 46 (4) ◽  
pp. 533-542 ◽  
Author(s):  
T. CHARD ◽  
M. L. FORSLING ◽  
M. A. R. JAMES ◽  
M. J. KITAU ◽  
J. LANDON
Keyword(s):  
Aqueous Solution ◽  
Biological Activity ◽  
Arginine Vasopressin ◽  
Late Pregnancy ◽  
Reducing Agents ◽  
Immunological Activity ◽  
Buffer Solution ◽  
Aqueous Buffer ◽  
Lysine Vasopressin ◽  
Other Substances

SUMMARY A radioimmunoassay for oxytocin in aqueous solution is described, with a sensitivity comparable with the best current bioassays. It is highly specific; arginine-vasopressin and lysine-vasopressin interfere only at 1000-fold greater concentration, while bradykinin, histamine, acetycholine and many other substances, which interfere with some bioassays, have no effect. In certain circumstances, there is a dissociation between loss of biological and immunological activity. Thus reducing agents had no effect on immunological activity, in contrast to their effect on biological activity. In late pregnancy plasma, the biological activity of oxytocin is destroyed more rapidly than the immunological activity. Radioimmunoassays have considerable advantages over bioassays both in convenience and specificity. However, bioassays should be employed for reference purposes because of the dissociation between biological and immunological activity that may occur.

scholarly journals Breadth of Neutralizing Antibodies Elicited by Stable, Homogeneous Clade A and Clade C HIV-1 gp140 Envelope Trimers in Guinea Pigs

2010 ◽  
Vol 84 (7) ◽  
pp. 3270-3279 ◽  
Author(s):  
Joseph P. Nkolola ◽  
Hanqin Peng ◽  
Ethan C. Settembre ◽  
Michael Freeman ◽  
Lauren E. Grandpre ◽  
...  
Keyword(s):  
Guinea Pigs ◽  
Neutralizing Antibodies ◽  
Recombinant Adenovirus ◽  
Neutralizing Antibody ◽  
Tier 2 ◽  
Antigenic Properties ◽  
Tier 1 ◽  
Clade C ◽  
Gp140 Envelope ◽  
Hiv 1

ABSTRACT The native envelope (Env) spike on the surface of human immunodeficiency virus type 1 (HIV-1) is trimeric, and thus trimeric Env vaccine immunogens are currently being explored in preclinical immunogenicity studies. Key challenges have included the production and purification of biochemically homogeneous and stable trimers and the evaluation of these immunogens utilizing standardized virus panels for neutralization assays. Here we report the binding and neutralizing antibody (NAb) responses elicited by clade A (92UG037.8) and clade C (CZA97.012) Env gp140 trimer immunogens in guinea pigs. These trimers have been selected and engineered for optimal biochemical stability and have defined antigenic properties. Purified gp140 trimers with Ribi adjuvant elicited potent, cross-clade NAb responses against tier 1 viruses as well as detectable but low-titer NAb responses against select tier 2 viruses from clades A, B, and C. In particular, the clade C trimer elicited NAbs that neutralized 27%, 20%, and 47% of tier 2 viruses from clades A, B, and C, respectively. Heterologous DNA prime, protein boost as well as DNA prime, recombinant adenovirus boost regimens expressing these antigens, however, did not result in an increased magnitude or breadth of NAb responses in this system. These data demonstrate the immunogenicity of stable, homogeneous clade A and clade C gp140 trimers and exemplify the utility of standardized tier 1 and tier 2 virus panels for assessing the NAb responses of candidate HIV-1 Env immunogens.

Differences in physicochemical and antigenic properties of chlamydial strains

1976 ◽  
Vol 22 (7) ◽  
pp. 937-941 ◽  
Author(s):  
H. Sayed ◽  
K. Fung ◽  
J. C. Wilt
Keyword(s):  
Protein Content ◽  
Chlamydia Psittaci ◽  
Immune Reactivity ◽  
Antigenic Analysis ◽  
Effective Period ◽  
Antigenic Properties ◽  
Isoelectric Points ◽  
Structural Differences ◽  
Cellular Immune ◽  
Cellular Components

Antigenic analysis of Chlamydia psittaci, C. trachomatis, and Lymphogranuloma venereum (LGV) revealed basic physicochemical differences among the three chlamydial strains. These were manifested in structural, isoelectric points, absorption spectra, and in the characteristics of the chromophobe-containing proteins. The effective period of sonication for C. psittaci and C. trachomatis is around 60 min during which the linkages most susceptible to external sonication forces were broken, releasing all attainable cellular components. Denaturation studies demonstrated that less than 50% of protein content of C. psittaci was denatured after 1 h of sonication, only 5% in the case of C. trachomatis. The protein and carbohydrate content of the most reactive fractions in macrophage-spreading inhibition test were different for LGV and C. trachomatis. The structural differences appear to determine the antigenic properties observed among the chlamydial strains as well as the specificity and probably the mechanisms (s) of cellular immune reactivity to Chlamydiae. This in turn may explain the failure of chlamydial vaccines, prepared from stock strains, to protect immunized children against 'wild' chlamydial strains.

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