Somatotropin as measured by a two-site time-resolved immunofluorometric assay.

1989 ◽  
Vol 35 (6) ◽  
pp. 913-917 ◽  
Author(s):  
C Strasburger ◽  
G Barnard ◽  
L Toldo ◽  
B Zarmi ◽  
Z Zadik ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Gh Deficiency ◽  
Polyclonal Antibodies ◽  
Immunoradiometric Assay ◽  
Time Resolved ◽  
Epitope Specificity ◽  
Accuracy And Precision ◽  
Hybridoma Technology ◽  
Criteria For Diagnosis ◽  
Serum Gh

Abstract To date, many of the current criteria for diagnosis of somatotropin (growth hormone, GH) deficiency have been based upon measurement of this hormone by competitive radioimmunoassay (RIA) with use of polyclonal antibodies. In recent years, however, the development of hybridoma technology has led to the generation of various monoclonal antibodies (Mabs) to GH with different affinities and epitope specificities. Subsequently, these reagents have been used in the development of noncompetitive two-site immunometric assays (e.g., immunoradiometric assay; IRMA). In general, the values obtained for serum GH by IRMA have been lower than those obtained by RIA, because of the epitope-specificity profile of the Mabs in the IRMA. Attempting to obtain GH values numerically similar to those by RIA, we used a combination of Mabs to GH in developing and evaluating a two-site time-resolved immunofluorometric assay (IFMA) based on the streptavidin-biotin interaction. Fluorescence is proportional to concentration of analyte and is linearly related to concentration over the range 0.3 to 40 micrograms/L. The assay was satisfactory with respect to sensitivity, accuracy, and precision (CV less than 10% over the entire working range). In addition, the concentration of GH was determined by the IFMA and a competitive RIA in serum obtained from GH deficient and acromegalic patients. The pairing of antibodies in the IFMA gave numerical values that agreed well with those by RIA (r = 0.97; n = 100).

Time-resolved immunofluorometric assay of human growth hormone

1993 ◽  
Vol 39 (8) ◽  
pp. 1620-1625 ◽  
Author(s):  
K Albertsson-Wikland ◽  
C Jansson ◽  
S Rosberg ◽  
A Novamo
Keyword(s):  
Growth Hormone ◽  
Human Growth Hormone ◽  
Polyclonal Antibodies ◽  
Human Growth ◽  
Immunoradiometric Assay ◽  
Serum Samples ◽  
Time Resolved ◽  
Counting Time ◽  
Pediatric Use ◽  
The Eu

Abstract We describe a time-resolved immunofluorometric assay (trIFMA) for human growth hormone (hGH), in which monoclonal antibody (mAb)-coated microtiter strip wells and a europium (Eu) chelate-labeled mAb are used. We compare the new trIFMA, in which two mAbs are used, with an immunoradiometric assay (IRMA) in which polyclonal antibodies are used. Serum samples (n = 185) from 36 children with various diagnoses were analyzed. In addition, 24-h profile samples (72 per child) from 39 children were analyzed. The trIFMA was more sensitive (detection limit, 0.03 mIU/L) than existing IRMAs. Both the intra- and interassay CVs were < or = 10.6% for hGH concentrations between 1 and 100 mIU/L. The trIFMA is technically simple and rapid, requires no centrifugation or separation reagent, and has a counting time of only 1 s per sample. In addition, the Eu label is nontoxic, presents no waste-disposal problems, and has a long shelf-life. Finally, the assay requires only small volumes of serum (25 muL), which is of considerable importance in pediatric use. The mAbs used for the trIFMA selectively bind the 22-kDa form of hGH, with the result that the assay detects about 80% of the amount detected by the polyclonal IRMA.

Interpretation of growth hormone provocative tests: comparison of cut-off values in four European laboratories

1995 ◽  
Vol 132 (3) ◽  
pp. 340-343 ◽  
Author(s):  
Anna-Maria Andersson ◽  
Hans Ørskov ◽  
Michael B Ranke ◽  
Steve Shalet ◽  
Niels E Skakkebæk
Keyword(s):  
Growth Hormone ◽  
University Hospital ◽  
Assay Method ◽  
Immunoradiometric Assay ◽  
Time Resolved ◽  
Assay Methods ◽  
High Degree ◽  
Serum Gh ◽  
Good Agreement ◽  
Growth And Reproduction

Andersson A-M, Ørskov H, Ranke MB, Shalet B, Skakkebæk NE. Interpretation of growth hormone provocative tests: comparison of cut-off values in four European laboratories. Eur J Endocrinol 1995;132:340–3. ISSN 0804–4643 To compare interpretations of growth hormone (GH) provocative tests in laboratories using six different GH immunoassays (one enzymeimmunometric assay (EIMA, assay 1), one immunoradiometric assay (IRMA, assay 5), one time-resolved fluorimmunometric assay (TRFIA, assay 3) and three radioimmunoassays (RIAs, assays 2, 4 and 6)), aliquots of peak samples from GH provocative tests were distributed between the four participating laboratories, quantified in the respective immunoassays and interpreted according to the cut-off values for provocative tests defined for each assay method. There was a high degree of relative correlation between the different assays, but absolute GH estimates differed. Assays 2, 4, 5 and 6 yielded almost identical GH levels. Assays 1 and 3 yielded serum GH levels approximately 39% and 70%, respectively, of those of assays 2, 4, 5 and 6. Although the absolute GH level measured in the various assay methods varied, there was good agreement between the interpretation of a given sample among the participating laboratories. This indicates that the differences in estimates of serum GH concentration by different immunoassay systems can be compensated for when cut-off values are defined for each method. Anna-Maria Andersson, Dept. of Growth and Reproduction, University Hospital of Copenhagen, Ward GR5064, 9 Blegdamsvej, DK-2100 Copenhagen Ø, Denmark

GROWTH HORMONE LEVELS IN NORMOGLYCEMIC AND HYPOGLYCEMIC INFANTS BORN SMALL FOR GESTATIONAL AGE

PEDIATRICS ◽  
1971 ◽  
Vol 48 (2) ◽  
pp. 190-199
Author(s):  
James R. Humbert ◽  
Ronald W. Gotlin
Keyword(s):  
Growth Hormone ◽  
Gestational Age ◽  
Small For Gestational Age ◽  
Gh Deficiency ◽  
Newborn Infants ◽  
Significant Rise ◽  
Glucose Levels ◽  
Appropriate For Gestational Age ◽  
A Prospective Study ◽  
Serum Gh

Recent investigations have raised the possibility that growth hormone (GH) influences intra-uterine weight and length. Moreover, the hypoglycemic tendency of small for gestational age (FSGA) infants and their small size could result from GH deficiency. To verify these hypotheses, a prospective study of daily serum GH and glucose levels was conducted in 46 newborn infants, including 18 FSCA infants, 18-full-term, appropriate for gestational age (FAGA), and 10 premature (PR) infants. Two FSGA babies became hypoglycemic. Both manifested normal GH competence as evidenced by normal daily GH levels, adequate GH response to arginine provocation, and satisfactory growth for over 2 years. Eleven of 12 FSGA babies followed from 14 to 26 months showed no evidence of impaired linear growth. The FSGA babies had GH values similar in magnitude and pattern to those of FAGA and PR infants. During the second half of the first postnatal day, a significant rise in serum GH occurred in all infants regardless of their size or gestational age; this rise may be the result of the stimulating effect of early milk feedings. GH deficiency does not appear to contribute to either the small size or hypoglycemic tendency of FSGA newborn infants.

GROWTH AND GROWTH HORMONE. IV. LIMITATIONS OF THE GROWTH HORMONE RESPONSE TO INSULIN AND ARGININE AND OF THE IMMUNOREACTIVE INSULIN RESPONSE TO ARGININE IN THE ASSESSMENT OF GROWTH HORMONE DEFICIENCY IN CHILDREN

PEDIATRICS ◽  
1969 ◽  
Vol 43 (6) ◽  
pp. 989-1004
Author(s):  
R. Youlton ◽  
S. L. Kaplan ◽  
M. M. Grumbach
Keyword(s):  
Growth Hormone ◽  
Growth Hormone Deficiency ◽  
Gh Deficiency ◽  
Hormone Deficiency ◽  
Insulin Administration ◽  
Arginine Infusion ◽  
Group 3 ◽  
Group 2 ◽  
Serum Gh ◽  
Group 1

The growth hormone (GH) response to insulin-induced hypoglycemia and to arginine infusion has been evaluated in 60 children with growth retardation. These children have been classified into three groups: Group 1-9 children had peak serum growth hormone values of 7 mµg/ml or greater to both stimuli, a normal growth hormone response. Group 2-18 children had peak GH values of ≤ 3 mµg/ml to both stimuli, an abnormal response indicating growth hormone deficiency. Group 3-6 children had a blunted GH response (> 3 < 7 mµg/ml) to both stimuli; 8 showed a normal rise in serum GH following arginine infusion (> 7 mµg/ml) but exhibited no rise, or a minimal one, following insulin administration; 9 children had minimal increase in serum GH concentration following arginine infusion but showed a normal GH response to insulin administration (> 7mµg/ml). Children included in Group 3 represent a heterogenous population. In some patients with a blunted response to both stimuli, evidence of partial or less severe form of GH deficiency was found, whereas in 17 of 18 children exhibiting a disparate response the impaired growth was not attributable to growth hormone deficiency. The blood glucose at all sampling periods was significantly lower following insulin administration in patients in Group 2 than that observed for children in Group 1 and 3. The blood glucose was significantly lower at 90 and 120 minutes following arginine infusion in Group 2 compared to values for patients in Group 1 and 3. Changes in serum insulin in response to the infusion of arginine did not provide a useful index of discrimination among these groups. Administration of diethylstilbestrol, 10 mg/day times 2 days, prior to testing can modify the GH response to both hypoglycemia and arginine; it is a useful ancillary procedure in children with blunted or disparate responses. These studies suggest that two types of stimulation tests are necessary to establish the diagnosis of isolated GH deficiency with a high degree of probability.

The effects of intranasal insufflation of growth hormone releasing factor analogie GRF1 – 29 NH2 on growth hormone secretion in children with short stature

1986 ◽  
Vol 113 (4_Suppl) ◽  
pp. S135-S138 ◽  
Author(s):  
M. BORKENSTEIN
Keyword(s):  
Growth Hormone ◽  
Short Stature ◽  
Gh Deficiency ◽  
Hormone Secretion ◽  
Growth Hormone Secretion ◽  
Normal Children ◽  
Serum Growth Hormone ◽  
Growth Hormone Releasing Factor ◽  
Serum Gh ◽  
Synthetic Growth

ABSTRACT The effects of intranasal insufflation of the synthetic growth hormone releasing factor GRF 1-29-NH2 on serum growth hormone (GH) were investigated in five healthy prepubertal children with short stature. 100 μg/kg/body weight of synthetic GRF 1-29-NH2, 500 μg in 100 μl water, were insufflated intranasally after careful cleaning of the nose. GRF 1-29-NH2 induced a prompt rise of serum GH levels with peak values at 15 minutes in all children investigated. Peak serum GH values were 28.3 ± 12.0 ng/ml (x̄ ± SD), range 17.1 - 47.6 ng/ml; Δ was 27.0 ± 12.2 ng/ml (x̄ ± SD). Serum GH levels were still significantly raised 120 minutes after the insufflation of GRF 1-29-NH2 (p < 0.05). No side effects, except for burning of the nasal mucosa in one patient, were observed. The results of this study demonstrate that intranasal insufflation of synthetic GRF 1-29-NH2 induces a prompt release of GH in otherwise normal children with short stature. Pulsatile intranasal insufflation of GRF 1-29-NH2 probably could be used for the treatment of some children with GH deficiency due to a defect at a suprapituitary level.

An Immunoradiometric Assay for Factor VIII Related Antigen (VIIIRAg) Using Two Monoclonal Antibodies-Comparison with Polyclonal Rabbit Antibodies for Use in von Willebrand’s Disease Diagnosis

1984 ◽  
Vol 52 (03) ◽  
pp. 250-252 ◽  
Author(s):  
Y Sultan ◽  
Ph Avner ◽  
P Maisonneuve ◽  
D Arnaud ◽  
Ch Jeanneau
Keyword(s):  
Monoclonal Antibodies ◽  
Structural Changes ◽  
Polyclonal Antibodies ◽  
Disease Diagnosis ◽  
Immunoradiometric Assay ◽  
Von Willebrand's Disease ◽  
Von Willebrand’S Disease ◽  
Structural Abnormalities ◽  
Antigenic Material ◽  
Von Willebrand

SummaryTwo monoclonal antibodies raised against FVIII/von Willebrand protein were used in an immunoradiometric assay (IRMA) to measure this antigen in normal plasma and plasma of patients with different forms of von Willebrand’s disease. The first antibody, an IgG1 was used to coat polystyrene tubes, the second one, an IgG2a, iodinated and used in the second step. Both antibodies inhibit ristocetin induced platelet agglutination and react strongly with platelets, megacaryocytes and endothelial cells. The IRMA test using these antibodies showed greater sensitivity than that using rabbit polyclonal anti VIIIRAg antibodies. A good correlation between the two tests was nevertheless found when VIIIRAg was measured in the majority of patient’s plasma. However 5 patients from 3 different families showed more antigenic material in the rabbit antibody IRMA than in the monoclonal antibody IRMA. It is suggested therefore that the monoclonal antibodies identify part of the VIIIR:Ag molecule showing structural abnormalities in these vWd patients, these structural changes remaining undetected by the polyclonal antibodies.

Consensus on the change of criteria for cure of acromegaly during the last decade

2011 ◽  
Vol 152 (18) ◽  
pp. 703-708 ◽  
Author(s):  
Gábor László Kovács ◽  
Judit Dénes ◽  
Erika Hubina ◽  
László Kovács ◽  
Sándor Czirják ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Growth Factor ◽  
Disease Control ◽  
Short Communication ◽  
Consensus Statement ◽  
Diagnosis And Treatment ◽  
Clinical Aspects ◽  
Insulin Like Growth Factor ◽  
Criteria For Diagnosis ◽  
Definition Of

The Acromegaly Consensus Group redefined the consensus criteria for cure of acromegaly. 74 neurosurgeons and experienced endocrinologists summarized the latest results on diagnosis and treatment of acromegaly. In this consensus statement the reliable growth hormone and insulin-like growth factor-1 assays were established. Definition of disease control was discussed based on the available publications and evidence. This short communication summarizes the clinical aspects of consensus criteria for diagnosis and cure of acromegaly based on the original article. Orv. Hetil., 2011, 152, 703–708.

Sign in / Sign up

Export Citation Format

Share Document