Immunoradiometric assay of carcinoembryonic antigen with use of avidin-biotin labeling.

1989 ◽  
Vol 35 (4) ◽  
pp. 573-576 ◽  
Author(s):  
J Peters ◽  
H Schmidt-Gayk ◽  
B Peters ◽  
F P Armbruster ◽  
A Quentmeier ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Carcinoembryonic Antigen ◽  
Dose Response ◽  
Response Curve ◽  
Tube Wall ◽  
Immunoradiometric Assay ◽  
Large Molecules ◽  
Standard Curve ◽  
Coefficients Of Variation ◽  
Biotin Labeling

Abstract In evaluating an enzyme-linked immunoassay of carcinoembryonic antigen (CEA) we found that the IgG fraction of polyclonal anti-CEA antibodies (DAKO) bound very well to the walls of polypropylene test tubes. We therefore developed an immunoradiometric CEA assay based on this binding of polyclonal anti-CEA antibody. We biotinylated a commercially available monoclonal antibody (Hybritech) and bound this to the CEA-anti-CEA bound to the tube wall. For detection we used 125I-labeled streptavidin. In comparison with several immunoassays for CEA this system offered several advantages such as greater linearity of the standard curve (from 0 to 74 micrograms/L), a steeper dose-response curve, and smaller coefficients of variation in the clinically useful range. This assay system may be used for other large molecules, so that only one tracer, the 125I-labeled streptavidin, has to be labeled; thus the technique seems suited for several different assays.

Immunoradiometric assay with use of magnetizable particles: measurement of thyrotropin in blood spots, to screen for neonatal hypothyroidism.

1986 ◽  
Vol 32 (10) ◽  
pp. 1966-1968 ◽  
Author(s):  
K V Waite ◽  
G F Maberly ◽  
G Ma ◽  
C J Eastman
Keyword(s):  
Incubation Time ◽  
Separation Procedure ◽  
Immunoradiometric Assay ◽  
Assay Sensitivity ◽  
Neonatal Hypothyroidism ◽  
Blood Spots ◽  
Standard Curve ◽  
Coefficients Of Variation ◽  
Specialized Equipment ◽  
Short Incubation Time

Abstract We adapted a commercial immunoradiometric assay (IRMA) to measure thyrotropin in filter-paper blood spots. Two 3-mm blood spots are used for each standard and sample. These are incubated for 2 h with radiolabeled antibody and for 30 min with magnetic antibody, followed by a 10-min separation procedure. Assay sensitivity is 6 milli-int. units/L. Coefficients of variation (precision profile of the standard curve) ranged from 4.3 to 9.6%. The coefficient of correlation (r) between thyrotropin concentrations in the blood spots and in serum was 0.93. Pre-elution of the blood spots is necessary for short incubation time. Short incubation time, little need for specialized equipment, the high precision and sensitivity characteristic of IRMA, and ease of collection, transport, and storage of the blood-spot samples make this assay suitable for neonatal hypothyroid screening.

Two-monoclonal-antibody "sandwich"-type assay of human lutropin, with no cross reaction with choriogonadotropin.

1987 ◽  
Vol 33 (9) ◽  
pp. 1603-1607 ◽  
Author(s):  
W D Odell ◽  
J Griffin
Keyword(s):  
Monoclonal Antibody ◽  
Monoclonal Antibodies ◽  
Detection Limit ◽  
Dose Response ◽  
Response Curve ◽  
Cross Reaction ◽  
Dose Response Curve ◽  
Low Doses ◽  
Human Choriogonadotropin ◽  
Sandwich Type

Abstract We have developed a sensitive, specific, noncompetitive sandwich-type assay for human lutropin (hLH). Two monoclonal antibodies are used, and there is no cross reaction with human choriogonadotropin (hCG) or human follitropin (hFSH), and little or none with human thyrotropin (hTSH). There also is no reaction with the free beta chains of hLH and hCG. The detection limit is less than 0.5 int. units of hLH per liter of serum, and the dose-response curve is linear between 0 and 10 int. units/L. The intra-assay CV averaged 5.4% at low doses of hLH; the interassay CV averaged 12.5%.

Double-antibody enzyme immunoassay applied to human alpha 1-fetoprotein.

1976 ◽  
Vol 22 (2) ◽  
pp. 198-204 ◽  
Author(s):  
L Belanger ◽  
D Hamel ◽  
D Dufour ◽  
M Pouliot
Keyword(s):  
Pregnant Women ◽  
Enzyme Immunoassay ◽  
Dose Response ◽  
Present Method ◽  
Response Curve ◽  
Dose Response Curve ◽  
Clinical Samples ◽  
Double Antibody ◽  
Coefficients Of Variation ◽  
Analytical Recovery

Abstract We report the development of a double-antibody system for enzyme immunoassay of human alpha 1-fetoprotein. Equilibrium and sequential saturation procedures were evaluated and compared with a similar double-antibody radioimmunoassay. With our method, 3 mug of alpha 1-fetoprotein per liter can be detected. The dose-response curve covers a 100-fold range of analyte concentrations. Within-run and between-run coefficients of variation are respectively 6.9% and 10.0%. Analytical recovery of added antigen is 99.5 +/- 10.6%. Results are routinely obtained in 24 h but can be obtained in less than 8 h. Alpha 1-fetoprotein was measured in a variety of clinical samples, including sera from 488 pregnant women. The advantages of the present method over radioimmunoassay and other enzyme immunoassay procedures are discussed.

Factor VII Clotting Assay: Influence of Different Thromboplastins and Factor VII-Deficient Plasmas

1991 ◽  
Vol 65 (02) ◽  
pp. 160-164 ◽  
Author(s):  
Marina Poggio ◽  
Armando Tripodi ◽  
Guglielmo Mariani ◽  
Pier Mannuccio Mannucci ◽  
Keyword(s):  
Heart Disease ◽  
Ischemic Heart Disease ◽  
Dose Response ◽  
Response Curve ◽  
Ischemic Heart ◽  
Factor Vii ◽  
Response Curves ◽  
Assay Sensitivity ◽  
Clinical Laboratories ◽  
Coagulant Activity

SummaryBeing a putative predictor of ischemic heart disease, the measurement of factor VII (FVTI) coagulant activity will be presumably requested to clinical laboratories with increasing frequency. To assess the influence on FVII assays of different thromboplastins and FVII-deficient plasmas we compared performances of all possible combinations of 5 thromboplastins and 6 deficient plasmas. The reproducibility of the clotting times of the dose-response curves for human and rabbit thromboplastins were acceptable (CV lower than 7%), whereas bovine thromboplastin had a higher CV. Reproducibility was very similar for all deficient plasmas when they were used in combination with a given thromboplastin. Responsiveness of the dose-response curve did not depend on the deficient plasma but rather on the thromboplastin: one rabbit thromboplastin was the least responsive, the bovine thromboplastin the most responsive, the human and the remaining two rabbit thromboplastins had intermediate responsiveness. Assay sensitivity to cold-activated FVII varied according to the thromboplastin: the bovine thromboplastin was the most sensitive, the human thromboplastin the least sensitive, of the three rabbit thromboplastins two were relatively sensitive, one was almost insensitive. In conclusion, our results indicate that thromboplastin rather than deficient plasma is the crucial factor in the standardization of FVII assay.

OVARIAN ASCORBIC ACID DEPLETION TEST FOR LUTEINIZING HORMONE

1967 ◽  
Vol 56 (4) ◽  
pp. 619-625 ◽  
Author(s):  
Hans Jacob Koed ◽  
Christian Hamburger
Keyword(s):  
Ascorbic Acid ◽  
Luteinizing Hormone ◽  
Dose Response ◽  
Response Curve ◽  
Dose Response Curve ◽  
Human Origin ◽  
Response Curves ◽  
Significant Difference ◽  
The Mean ◽  
Different Levels

ABSTRACT Comparison of the dose-response curves for LH of ovine origin (NIH-LH-S8) and of human origin (IRP-HMG-2) using the OAAD test showed a small, though statistically significant difference, the dose-response curve for LH of human origin being a little flatter. Two standard curves for ovine LH obtained with 14 months' interval, were parallel but at different levels of ovarian ascorbic acid. When the mean ascorbic acid depletions were calculated as percentages of the control levels, the two curves for NIH-LH-S8 were identical. The use of standards of human origin in the OAAD test for LH activity of human preparations is recommended.

HYPERTROPHIC ADRENALS AND THEIR RESPONSE TO STRESS AFTER LESIONS IN THE MEDIAN EMINENCE OF TOTALLY HYPOPHYSECTOMIZED PIGEONS

1961 ◽  
Vol 37 (4) ◽  
pp. 565-576 ◽  
Author(s):  
Richard A. Miller
Keyword(s):  
Dose Response ◽  
Median Eminence ◽  
Response Curve ◽  
Liver Parenchyma ◽  
Dose Response Curve ◽  
Pars Distalis ◽  
Adrenal Enlargement ◽  
Response To Stress ◽  
Lethal Doses ◽  
Chromaffin Tissue

ABSTRACT Four per cent formaldehyde, insulin, or epinephrine in oil was injected for 5 days into pigeons subjected to varying degrees of hypophysectomy alone or together with large lesions in the median eminence and hypothalamus. Adrenals atrophied after the removal of the pars distalis alone or together with the neurohypophysis in untreated pigeons but showed markedly hypertrophic interrenal tissue (cortex in mammals) after treatment with formaldehyde or insulin. The slope of the dose-response curve was similar in operated and unoperated pigeons. The accumulation of bile in the liver parenchyma, which may occur after removal of the pars distalis, is an endogenous stress which was associated regularly with adrenal hypertrophy. After very large lesions of the median eminence and ventral hypothalamus in addition to total hypophysectomy, adrenals hypertrophied rather than atrophied, and the response to formaldehyde paralleled that in intact and »hypohysectomized« pigeons. Interrenal tissue was stimulated regularly; chromaffin tissue was partially degranulated, sometimes showed hyperplasia with colchicine, but only occasionally appeared hypertrophied. Epinephrine in nearly lethal doses caused only minimal adrenal enlargement. After adrenal denervation followed by hypophysectomy, the adrenals were still stimulated by formaldehyde. It appears that the interrenal tissue of the pigeon responds to a humoral stimulus not of hypophyseal origin in the absence of the hypophyseal-hypothalamic system.

ANTI-OVULATORY ACTIVITY OF STEROIDS ADMINISTERED BY GAVAGE IN THE ADULT OESTRUS RABBIT

1963 ◽  
Vol 42 (2_Suppl) ◽  
pp. S17-S30
Author(s):  
Fred A. Kind ◽  
Ralph I. Dorfman
Keyword(s):  
Dose Response ◽  
Active Compound ◽  
Subcutaneous Injection ◽  
Response Curve ◽  
Parent Compound ◽  
Dose Response Curve ◽  
Relative Potency ◽  
Reference Standard ◽  
Highly Active ◽  
Dose Levels

ABSTRACT Thirty-seven steroids have been studied as orally effective inhibitors of ovulation in the mated oestrus rabbit. Norethisterone served as the reference standard and a dose response curve was established between the 0.31 and 1.25 mg dose levels. Nine highly active anti-ovulatory compounds are described listed in a decreasing order of potency with norethisterone having the arbitrary value of one: 6-chloro-Δ6-dehydro-17α-acetoxyprogesterone (35), 6α-methyl-Δ1-dehydro-17α-acetoxyprogesterone (≥ 10), 6-fluoro-Δ6-dehydro-17α-acetoxyprogesterone(9), 6-methyl-Δ6-dehydro-17α-acetoxyprogesterone (5), Δ6-dehydro-17α-acetoxyprogesterone (≥ 3), 6α-methyl-17α-acetoxyprogesterone (2.6), 6-chloro-Δ1,6-bisdehydro-17α-acetoxyprogesterone (≥ 2), 2-hydroxymethyl-17α-methyl-17β-hydroxyandrostan-3-one (≥ 2), and 6α-fluoro-16α-methyl-17α-acetoxyprogesterone (≥ 1.25). The anti-ovulatory activity of a compound was not related necessarily to the progestational activity of a compound nor to the anti-gonadotrophic activity as measured in parabiotic rats. 6-Chloro-Δ60dehydro-17-acetoxyprogesterone was as effective by gavage as previously shown by subcutaneous injection. 2-Hydroxymethyl-17α-methyl-17β-hydroxyandrostan-3-one was at least 2.5 times more active by gavage than by injection. While 17α-acetoxyprogesterone was a very weak anti-ovulatory steroid, modifications of the structure by addition of methyl or halogen at the 6α position with or without unsaturation greatly increased the activity. 6-Chloro-Δ6-dehydro-27α-acetoxyprogesterone was the most active compound in this series showing a relative potency of 3500 times that of the parent compound 17α-acetoxyprogesterone.

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