scholarly journals Macroprolactinemia: Diagnostic, Clinical, and Pathogenic Significance

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Akira Shimatsu ◽  
Naoki Hattori
Keyword(s):  
Middle Age ◽  
Molecular Form ◽  
Protein A ◽  
Gel Filtration ◽  
Cross Reactivity ◽  
Precipitation Method ◽  
Binding Studies ◽  
Rat Pituitary ◽  
Peg Precipitation Method

Macroprolactinemia is characterized by a large molecular mass of PRL (macroprolactin) as the main molecular form of PRL in sera, the frequent elevation of serum PRL (hyperprolactinemia), and the lack of symptoms. Macroprolactin is largely a complex of PRL with immunoglobulin G (IgG), especially anti-PRL autoantibodies. The prevalence of macroprolactinemia is 10–25% in patients with hyperprolactinemia and 3.7% in general population. There is no gender difference and a long-term followup demonstrates that macroprolactinemia develops before middle age and is likely a chronic condition. Polyethylene-glycol- (PEG-) precipitation method is widely used for screening macroprolactinemia, and gel filtration chromatography, protein A/G column, andI125-PRL binding studies are performed to confirm and clarify its nature. The cross-reactivity of macroprolactin varies widely according to the immunoassay systems. The epitope on PRL molecule recognized by the autoantibodies is located close to the binding site for PRL receptors, which may explain that macroprolactin has a lower biological activity. Hyperprolactinemia frequently seen in macroprolactinemic patients is due to the delayed clearance of autoantibody-bound PRL. When rats are immunized with rat pituitary PRL, anti-PRL autoantibodies are produced and hyperprolactinemia develops, mimicking macroprolactinemia in humans. Screening of macroprolactinemia is important for the differential diagnosis of hyperprolactinemia to avoid unnecessary examinations and treatments.

scholarly journals Direct and Label-Free Determination of Human Glycated Hemoglobin Levels Using Bacteriorhodopsin as the Biosensor Transducer

Sensors ◽  
2020 ◽  
Vol 20 (24) ◽  
pp. 7274
Author(s):  
Ying-Chin Lin ◽  
Ching-Yu Lin ◽  
Hsiu-Mei Chen ◽  
Li-Pin Kuo ◽  
Cheng-En Hsieh ◽  
...  
Keyword(s):  
Dynamic Range ◽  
Glycated Hemoglobin ◽  
Incident Light ◽  
Protein A ◽  
Cross Reactivity ◽  
Single Step ◽  
Clinical Samples ◽  
Label Free ◽  
Hba1c Levels

Glycated hemoglobin (HbA1c) levels are an important index for the diagnosis and long-term control of diabetes. This study is the first to use a direct and label-free photoelectric biosensor to determine HbA1c using bacteriorhodopsin-embedded purple membranes (PM) as a transducer. A biotinylated PM (b-PM) coated electrode that is layered with protein A-oriented antibodies against hemoglobin (Hb) readily captures non-glycated Hb (HbA0) and generates less photocurrent. The spectra of bacteriorhodopsin and Hb overlap so the photocurrent is reduced because of the partial absorption of the incident light by the captured Hb molecules. Two HbA0 and HbA1c aptasensors that are prepared by conjugating specific aptamers on b-PM coated electrodes single-step detect HbA0 and HbA1c in 15 min, without cross reactivity, with detection limits of ≤0.1 μg/mL and a dynamic range of 0.1–100 μg/mL. Both aptasensors exhibit high selectivity and long-term stability. For the clinical samples, HbA0 concentrations and HbA1c levels that are measured with aptasensors correlate well with total Hb concentrations and the HbA1c levels that are determined using standard methods (correlation gradient = 0.915 ± 0.004 and 0.981 ± 0.001, respectively). The use of these aptasensors for diabetes care is demonstrated.

Purification of Tetragalloylglucose 4-O-Galloyltransferase and Preparation of Antibodies against This Key Enzyme in the Biosynthesis of Hydrolyzable Tannins

2000 ◽  
Vol 55 (7-8) ◽  
pp. 582-587 ◽  
Author(s):  
Petra Grundhöfer ◽  
Georg G. Gross
Keyword(s):  
Quercus Robur ◽  
Polyclonal Antibodies ◽  
Protein A ◽  
Gel Filtration ◽  
Cross Reactivity ◽  
Pedunculate Oak ◽  
Hydrolyzable Tannins ◽  
Apparent Homogeneity ◽  
Key Enzyme ◽  
Rhus Typhina

Abstract The enzyme, β-glucogallin: 1,2,3,6-tetra-O-galloyl- β-ᴅ-glucose 4-O-galloyltransferase, which catalyzes the last common step in the biosynthesis of the two subclasses of hydrolyzable tannins, i.e. gallotannins and ellagitannins, was purified 868-fold from leaves of pedunculate oak ( Quercus robur, syn. Q. pedunculata) to apparent homogeneity. Polyclonal antibodies against this pivotal enzyme were raised in rabbits and purified by protein-A chromatography, gel-filtration and affinity complexation. They were found to react specifically with acyltransferase from oak, displaying no cross-reactivity towards analogous enzymes from other plants synthesizing hydrolyzable tannins along the same biogenetic route, e.g. Rhus typhina or Tellima grandiflora.

scholarly journals Structural comparison of two esterases from Drosophila mojavensis isolated by immunoaffinity chromatography

1986 ◽  
Vol 238 (3) ◽  
pp. 691-699 ◽  
Author(s):  
J Pen ◽  
J Van Beeumen ◽  
J J Beintema
Keyword(s):  
Gel Electrophoresis ◽  
High Efficiency ◽  
Polyacrylamide Gel Electrophoresis ◽  
Protein A ◽  
Gel Filtration ◽  
Immunoaffinity Chromatography ◽  
Cross Reactivity ◽  
Drosophila Mojavensis ◽  
Structural Comparison ◽  
Final Purification

Antibodies raised against esterase-4 and esterase-5 from Drosophila mojavensis were coupled to Protein A-Sepharose CL-4B to prepare high-efficiency immunomatrices used for their purification. Final purification was achieved by anion-exchange h.p.l.c., in the case of esterase-5 followed by gel-filtration h.p.l.c. The resultant esterase preparations were homogeneous, as judged by gel-filtration h.p.l.c., SDS/polyacrylamide-gel electrophoresis and non-denaturing gel electrophoresis. Esterase-4 and esterase-5 are the products of a duplicated gene. They are differently localized in the insect's body and expressed in different periods during development. Although both enzymes exhibit little immunological cross-reactivity, their amino acid compositions show few significant differences and their N-terminal sequences are largely identical, which clearly show their common origin.

scholarly journals Purification and characterization of protein disulphide-isomerase from the unicellular green alga Chlamydomonas reinhardii. A 120 kDa dimer antigenically distinct from the vertebrate enzyme

1990 ◽  
Vol 268 (1) ◽  
pp. 63-68 ◽  
Author(s):  
D D Kaska ◽  
K I Kivirikko ◽  
R Myllylä
Keyword(s):  
Green Alga ◽  
Polyclonal Antibodies ◽  
Active Form ◽  
Protein A ◽  
Gel Filtration ◽  
Cross Reactivity ◽  
Chlamydomonas Reinhardii ◽  
Protein Disulphide Isomerase ◽  
Unicellular Green Alga ◽  
A Subunit

Protein disulphide-isomerase (PDI) has been isolated from the unicellular green alga Chlamydomonas reinhardii and purified by (NH4)2SO4 precipitation, gel filtration and DEAE-Sephacel, hydroxyapatite and f.p.l.c. chromatography. The active algal enzyme is a 120 kDa dimer with a subunit molecular mass of 60 kDa when determined by SDS/PAGE. Although similar in size to the previously isolated vertebrate PDIs, the algal enzyme is antigenically distinct, polyclonal antibodies against the algal PDI showing no cross-reactivity with the vertebrate enzyme on immunoblots, and vice versa. The anti-(algal PDI) antiserum did not inhibit algal PDI activity, and C. reinhardii PDI could be immobilized on anti-PDI-Protein A-Sepharose in active form. In contrast with the situation in vertebrates, where PDI functions as a subunit of prolyl 4-hydroxylase, the C. reinhardii PDI is not associated with the algal prolyl 4-hydroxylase.

scholarly journals The natural history of macroprolactinaemia

2012 ◽  
Vol 166 (4) ◽  
pp. 625-629 ◽  
Author(s):  
Naoki Hattori ◽  
Takashi Adachi ◽  
Takashi Ishihara ◽  
Akira Shimatsu
Keyword(s):  
Natural History ◽  
Chronic Condition ◽  
Middle Age ◽  
Gel Filtration ◽  
Serum Prolactin ◽  
Hospital Workers ◽  
Binding Studies ◽  
Large Molecular Weight ◽  
History Of ◽  
Free Serum

ObjectiveMacroprolactinaemia is a condition in which serum prolactin (PRL) consists mainly of large molecular weight PRL (macroPRL). The aim of this study was to examine the natural history of macroprolactinaemia.Design and participantsSix hundred and fifty-four hospital workers participated in this study, including 27 subjects with macroprolactinaemia and 627 controls. MacroPRL and serum PRL concentrations were evaluated over a 4-year period. The ratio of macroPRL was examined by the polyethylene glycol (PEG) method and gel filtration chromatography. IgG-bound PRL and anti-PRL autoantibodies were examined by protein G and 125I-PRL binding studies respectively.ResultsOver the 4 years of the study, all 27 macroprolactinaemic subjects had persistent macroprolactinaemia without the development of raised free PRL, while none of the 627 controls developed macroprolactinaemia. The ratios of PEG–precipitable PRL and IgG-bound PRL did not significantly change, but 125I-PRL binding ratios significantly increased. As a whole, total and free serum PRL concentrations did not significantly change in subjects with macroprolactinaemia over the 4-year period. However, hyperprolactinaemia developed in five of the 18 macroprolactinaemic subjects who were initially normoprolactinaemic along with an increase in anti-PRL autoantibody titres. One of the remaining nine macroprolactinaemic subjects who were initially hyperprolactinaemic showed a decrease in serum PRL concentrations, which occurred concomitantly with a decrease in the anti-PRL autoantibody titre.ConclusionsMacroprolactinaemia may develop before middle age and is likely a chronic condition leading to hyperprolactinaemia.

scholarly journals Waning antibody responses in COVID-19: what can we learn from the analysis of other coronaviruses?

Infection ◽  
2021 ◽  
Author(s):  
Ali Hamady ◽  
JinJu Lee ◽  
Zuzanna A. Loboda
Keyword(s):  
Cross Reactivity ◽  
Antibody Responses ◽  
The Novel ◽  
Incidence And Mortality ◽  
Antibody Titres ◽  
Human Coronaviruses ◽  
Public Health Strategies ◽  
Antibody Dynamics

Abstract Objectives The coronavirus disease 2019 (COVID-19), caused by the novel betacoronavirus severe acute respiratory syndrome 2 (SARS-CoV-2), was declared a pandemic in March 2020. Due to the continuing surge in incidence and mortality globally, determining whether protective, long-term immunity develops after initial infection or vaccination has become critical. Methods/Results In this narrative review, we evaluate the latest understanding of antibody-mediated immunity to SARS-CoV-2 and to other coronaviruses (SARS-CoV, Middle East respiratory syndrome coronavirus and the four endemic human coronaviruses) in order to predict the consequences of antibody waning on long-term immunity against SARS-CoV-2. We summarise their antibody dynamics, including the potential effects of cross-reactivity and antibody waning on vaccination and other public health strategies. At present, based on our comparison with other coronaviruses we estimate that natural antibody-mediated protection for SARS-CoV-2 is likely to last for 1–2 years and therefore, if vaccine-induced antibodies follow a similar course, booster doses may be required. However, other factors such as memory B- and T-cells and new viral strains will also affect the duration of both natural and vaccine-mediated immunity. Conclusion Overall, antibody titres required for protection are yet to be established and inaccuracies of serological methods may be affecting this. We expect that with standardisation of serological testing and studies with longer follow-up, the implications of antibody waning will become clearer.

scholarly journals An optimized and robust PEG precipitation method for detection of SARS-CoV-2 in wastewater

2021 ◽  
Vol 785 ◽  
pp. 147270
Author(s):  
Sylvia A. Sapula ◽  
Jonathan J. Whittall ◽  
Aaron J. Pandopulos ◽  
Cobus Gerber ◽  
Henrietta Venter
Keyword(s):  
Precipitation Method ◽  
Peg Precipitation Method

Release of cholecystokinin and secretin by sodium oleate in dogs: molecular form and bioactivity

1992 ◽  
Vol 262 (1) ◽  
pp. G35-G43 ◽  
Author(s):  
G. Sun ◽  
T. M. Chang ◽  
W. J. Xue ◽  
J. F. Wey ◽  
K. Y. Lee ◽  
...  
Keyword(s):  
Pancreatic Juice ◽  
Sodium Oleate ◽  
Molecular Form ◽  
Gel Filtration ◽  
Exchange Chromatography ◽  
Conscious Dogs ◽  
Oral Ingestion ◽  
Intraduodenal Infusion ◽  
Predominant Form ◽  
Duodenal Lumen

The release of cholecystokinin (CCK) and secretin into both circulation and duodenal lumen, after intraduodenal perfusion with sodium oleate or oral ingestion of fat, was studied in anesthetized and conscious dogs, respectively. Intraduodenal infusion with sodium oleate (4 mmol.kg.-1.h-1, pH 9.5) in anesthetized dogs with diversion of bile and pancreatic juice stimulated the release of both CCK and secretin not only into the circulation but also into the duodenal lumen. The concentration of CCK and secretin in the luminal perfusate increased from 0.2 +/- 0.1 to 2.1 +/- 0.4 nM and 0.34 +/- 0.16 to 2.59 +/- 0.63 nM, respectively. Intraduodenal infusion of NaHCO3 solution at pH 9.5 did not result in release of either hormone. Luminal release of both hormones was also observed by intraduodenal infusion of sodium oleate in the dogs without diversion of bile and pancreatic juice, albeit at lower concentrations than those released in the dogs with diversion. Analysis of the molecular form of luminal secretin by gel filtration, ion-exchange chromatography, and high-performance liquid chromatography showed only a single form of secretin with molecular size, hydrophobicity, and charge similar to those of natural porcine secretin. In contrast, multiple forms of CCK were released into both circulation and duodenal lumen with CCK-58 as the predominant form. In conscious dogs, CCK-58 was also found to be the predominant form of CCK released into the circulation after oral ingestion of fat.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Presence in human eosinophils of a lysophospholipase similar to that found in the pancreas

1995 ◽  
Vol 309 (1) ◽  
pp. 141-144 ◽  
Author(s):  
F W Holtsberg ◽  
L E Ozgur ◽  
D E Garsetti ◽  
J Myers ◽  
R W Egan ◽  
...  
Keyword(s):  
Synthetic Peptide ◽  
Protein A ◽  
Pancreatic Enzyme ◽  
Gel Filtration ◽  
Pancreatic Tissue ◽  
Supernatant Fraction ◽  
Polyadenylated Rna ◽  
Rabbit Polyclonal Antibody ◽  
Dna Fragment ◽  
Lysophospholipase Activity

The supernatant fraction from lysed human eosinophils, when separated by gel-filtration chromatography, contains a protein with lysophospholipase activity of approximate molecular mass 74 kDa. This mass differs substantially from the 17 kDa of a previously cloned eosinophil lysophospholipase (Charcot-Leyden crystal protein), but is similar to that reported for a pancreatic enzyme. We have therefore further characterized this pancreatic-like lysophospholipase in human eosinophils. A rabbit polyclonal antibody was produced against a synthetic peptide consisting of amino acids 325-349 from the 74 kDa rat pancreatic lysophospholipase. Western-blot analysis of eosinophil extracts indicate that this antibody recognizes a single 74 kDa band in these preparations. Incubation of the supernatant fraction from sonified eosinophils with this antibody, followed by precipitation of antibody-antigen complexes with Protein A, removes the majority of the lysophospholipase activity. Indirect immunofluorescence examination with this antibody indicates this protein to be localized to granules of eosinophils and not in other leucocytes. Moreover, reverse transcriptase PCR of polyadenylated RNA from eosinophils and from rat pancreatic tissue with primers to rat pancreatic lysophospholipase resulted in readily detectable 1 kb DNA products in both samples. Sequencing revealed this DNA fragment to be identical with the human pancreatic lysophospholipase cDNA sequence. Taken together, these data indicate that eosinophils contain a lysophospholipase that is similar to the human pancreatic enzyme.

UT-B1 proteins in rat: tissue distribution and regulation by antidiuretic hormone in kidney

2002 ◽  
Vol 283 (5) ◽  
pp. F912-F922 ◽  
Author(s):  
M.-M. Trinh-Trang-Tan ◽  
F. Lasbennes ◽  
P . Gane ◽  
N. Roudier ◽  
P. Ripoche ◽  
...  
Keyword(s):  
Antidiuretic Hormone ◽  
Brain Cortex ◽  
Rat Kidney ◽  
Cross Reactivity ◽  
Ependymal Cells ◽  
Kidney Medulla ◽  
Vasa Recta ◽  
Cell Processes ◽  
Rat Tissue

UT-B1 is the facilitated urea transporter of red blood cells (RBCs) and endothelial cells of descending vasa recta in the kidney. Immunoblotting with a polyclonal antibody against the C-ter sequence of rat UT-B1 revealed UT-B1 as both nonglycosylated (29 kDa) and N-glycosylated (47.5 and 33 kDa) proteins in RBC membranes, kidney medulla, brain, and bladder in rat. In testis, UT-B1 was expressed only as a nonglycosylated protein of 47.5 kDa. Immunocytochemistry confirmed that the location of UT-B1 is restricted to descending vasa recta. In brain, UT-B1 protein was found in astrocytes and ependymal cells. Cell bodies and perivascular end feet of astrocytes were labeled in brain cortex, whereas astrocyte cell processes were labeled in corpus callosum. Flow cytometry analysis of RBCs revealed a good cross-reactivity of the antibody with mouse and human UT-B1. UT-B1 protein expression in rat kidney medulla was downregulated greatly by long-term [deamino-Cys1,d-Arg8]vasopressin infusion and moderately by furosemide treatment. This study discloses an uneven distribution of UT-B1 protein within astrocytes and the regulation of renal UT-B1 protein by antidiuretic hormone.

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