Immunogamma Globulin Research Articles

Prediction of metabolic clusters in early-lactation dairy cows using models based on milk biomarkers

The aim of this study was to describe metabolism of early-lactation dairy cows by clustering cows based on glucose, insulin-like growth factor I (IGF-I), free fatty acid, and β-hydroxybutyrate (BHB) using the k-means method. Predictive models for metabolic clusters were created and validated using 3 sets of milk biomarkers (milk metabolites and enzymes, glycans on the immunogamma globulin fraction of milk, and Fourier-transform mid-infrared spectra of milk). Metabolic clusters are used to identify dairy cows with a balanced or imbalanced metabolic profile. Around 14 and 35 d in milk, serum or plasma concentrations of BHB, free fatty acids, glucose, and IGF-I were determined. Cows with a favorable metabolic profile were grouped together in what was referred to as the "balanced" group (n = 43) and were compared with cows in what was referred to as the "other balanced" group (n = 64). Cows with an unfavorable metabolic profile were grouped in what was referred to as the "imbalanced" group (n = 19) and compared with cows in what was referred to as the "other imbalanced" group (n = 88). Glucose and IGF-I were higher in balanced compared with other balanced cows. Free fatty acids and BHB were lower in balanced compared with other balanced cows. Glucose and IGF-I were lower in imbalanced compared with other imbalanced cows. Free fatty acids and BHB were higher in imbalanced cows. Metabolic clusters were related to production parameters. There was a trend for a higher daily increase in fat- and protein-corrected milk yield in balanced cows, whereas that of imbalanced cows was higher. Dry matter intake and the daily increase in dry matter intake were higher in balanced cows and lower in imbalanced cows. Energy balance was continuously higher in balanced cows and lower in imbalanced cows. Weekly or twice-weekly milk samples were taken and milk metabolites and enzymes (milk glucose, glucose-6-phosphate, BHB, lactate dehydrogenase, N-acetyl-β-d-glucosaminidase, isocitrate), immunogamma globulin glycans (19 peaks), and Fourier-transform mid-infrared spectra (1,060 wavelengths reduced to 15 principal components) were determined. Milk biomarkers with or without additional cow information (days in milk, parity, milk yield features) were used to create predictive models for the metabolic clusters. Accuracy for prediction of balanced (80%) and imbalanced (88%) cows was highest using milk metabolites and enzymes combined with days in milk and parity. The results and models of the present study are part of the GplusE project and identify novel milk-based phenotypes that may be used as predictors for metabolic and performance traits in early-lactation dairy cows.

Distinct features between longitudinally extensive transverse myelitis presenting with and without anti-Aquaporin 4 antibodies

Objectives: Longitudinally extensive transverse myelitis (LETM) with spinal cord lesions spanning three or more vertebral segments is a key feature of neuromyelitis optica (NMO). However, the role of anti-aquaporin 4 (anti-AQP4) antibody, a sensitive biomarker of NMO, in the conversion of LETM to NMO remains uncertain. Methods: Thirty first-ever LETM patients were retrospectively analysed and divided into two groups according to the presence of anti-AQP4 antibodies. Results: Eighteen (60%) patients presented with anti-AQP4 antibodies. Fifteen (83.33%) anti-AQP4 (+) LETM patients converted to NMO, while only three of 12 (25%, p = 0.002) anti-AQP4 (-) LETM patients progressed to NMO, over a mean follow-up period of 5.63 years. Seven (38.89%) anti-AQP4 (+) and one (8.33%) anti-AQP4 (-) LETM patients received interferon-β1a treatment, respectively. Anti-AQP4 (+) LETM patients demonstrated a higher immunogamma globulin (IgG) index (0.68 ± 0.43 versus 0.47 ± 0.19, p = 0.018), annual relapse rate (0.72 ± 0.31 versus 0.42 ± 0.17, p = 0.01) and Kurtzke Expanded Disability Status Scale (4.28 ± 2.22 versus 2.67 ± 2.26, p = 0.031), than anti-AQP4 (-) LETM patients. In spinal magnetic resonance imaging (MRIs), more than half (58.33%) of the anti-AQP4 (+) LETM patients were observed to have central grey matter-predominant involvement in the axial view, while peripheral white matter-predominant involvement (51.85%) was the most common pattern observed in the anti-AQP4 (-) LETM patients. Conclusion: Anti-AQP4 (+) LETM demonstrated a high conversion rate to NMO (83.33%), suggesting that anti-AQP4 (+) LETM may represent an early, isolated syndrome of NMO spectrum disorder. The greater number of patients receiving interferon-β treatment in anti-AQP4 (+) LETM may contribute to its high annual relapse rate.

Multiplexed dot immunoassay using Ag nanocubes, Au/Ag alloy nanoparticles, and Au/Ag nanocages

We report the first application of Ag nanocubes, Au/Ag alloy nanoparticles, and Au/Ag nanocages in a multiplexed dot immunoassay. The assay principle is based on the staining of analyte drops on a nitrocellulose membrane strip by using multicolor nanoparticles conjugated with biospecific probing molecules. Nanoparticles were prepared by a galvanic replacement reaction between the Ag atoms of silver nanocubes and Au ions of tetrachloroauric acid. Depending on the Ag/Au conversion ratio, the particle plasmon resonance was tuned from 450 to 700 nm and the suspension color changed from yellow to blue. The particles of yellow, red, and blue suspensions were functionalized with chicken, rat, and mouse immuno gamma globulin (IgG) molecular probes, respectively. The multiplex capability of the assay was illustrated by a proof-of-concept experiment involving simultaneous one-step determination of target molecules (rabbit anti-chicken, anti-rat, and anti-mouse antibodies) with a mixture of fabricated conjugates. Under naked eye examination, no cross-colored spots or nonspecific bioconjugate adsorption were observed, and the low detection limit was about 20 fmol. Open image in new window

High-Q polymer-coated microspheres for immunosensing applications

Homogeneous polymeric thin layers have been used as functionalizing agents on silica microspherical resonators in view of the implementation of an immunosensor. We have characterized the microspheres functionalized with poly-L-lactic acid and Eudragit L100, as an alternative to the commonly used 3-Aminopropyltrimethoxysilane. It is shown that polymeric functionalization does not affect the high quality factor (Q greater than 10(7)) of the silica microspheres, and that the Q factor is about 3 x 10(5) after chemical activation and covalent binding of immunogammaglobulin (IgG). This functionalizing process of the microresonator constitutes a promising step towards the achievement of an ultra sensitive immunosensor.

Studies of Adsorption and Viscoelastic Properties of Proteins onto Liquid Crystal Phthalocyanine Surface Using Quartz Crystal Microbalance with Dissipation Technique

This paper presents time-resolved adsorption behavior of lysozyme, bovine serum albumin (BSA), and immunogamma globulin (IgG) onto a liquid crystal phthalocyanine surface and concentrates on the kinetic, viscoelastic variation, interfacial hydration, and structural details obtained by quartz crystal microbalance dissipating monitoring (QCM-D) technique with the Voigt model. The rate of adsorption for lysozyme is faster than that of BSA and IgG. The Freundlich model can explain the adsorption isotherm of lysozyme, whereas an exponential growth model can describe that of BSA and IgG. Layer surface coverage has been found to increase for all three proteins with significant variation in surface packing density and viscoelastic parameters within the investigated concentration range. The adsorbed IgG and BSA form soft, water-rich multilayers with large energy dissipation. The layer viscosity and shear modulus have been found to decrease as the protein hydration increases with concentration in these cases. On th...

Free-solvent model shows osmotic pressure is the dominant factor in limiting flux during protein ultrafiltration

In protein ultrafiltration (UF), the limiting flux phenomenon has been generally considered a consequence of the presence of membrane fouling or the perceived formation of a cake/gel layer that develops at high operating pressures. Subsequently, numerous theoretical models on gel/cake physics have been made to address how these factors can result in limiting flux. In a paradigm shift, the present article reestablishes the significance of osmotic pressure by examining its contribution to limiting flux in the framework of the recently developed free solvent osmotic pressure model. The resulting free-solvent-based flux model (FSB) uses the Kedem–Katchalsky model, film theory and the free solvent representation for osmotic pressure in its development. Single protein tangential-flow diafiltration experiments (30 kDa MWCO CRC membranes) were also conducted using ovalbumin (OVA, 45 kDa), bovine serum albumin (BSA, 69 kDa), and immuno-gamma globulin (IgG, 155 kDa) in moderate NaCl buffered solutions at pH 4.5, 5.4, 7 and 7.4. The membrane was preconditioned to minimize membrane fouling development during the experimental procedure. The pressure was randomly selected and flux and sieving were determined. The experimental results clearly demonstrated that the limiting flux phenomenon is not dominated by membrane fouling and the FSB model theoretically illustrates that osmotic pressure is the primary factor in limiting flux during UF. The FSB model provides excellent agreement with the experimental results while producing realistic protein wall concentrations. In addition, the pH dependence of the limiting flux is shown to correlate to the pH dependency of the specific protein diffusion coefficient.

Spinning-disk self-referencing interferometry of antigen-antibody recognition.

A gold ridge microstructure fabricated to a height of lambda/8 on a high-reflectivity substrate behaves as a wave-front-splitting self-referencing interferometer in phase quadrature when illuminated by a Gaussian laser beam and observed in the far field along the optic axis. When immuno-gammaglobulin (IgG) antibodies are selectively immobilized on the gold microstructure, they recognize and bind to a specific antigen, which shifts the relative optical phase of the interferometer and modifies the far-field diffracted intensity. We detect bound antigen interferometrically on spinning disks at a sampling rate of 100 kHz and verify the interferometric nature of the signal by using two quadratures of opposite sign to rule out effects of dynamic light scattering. Strong molecular recognition is demonstrated by the absence of binding to nontarget molecules but strong signal change in response to a specific antigen. This BioCD has the potential to be applied as a spinning-disk interferometric immunoassay and biosensor.

Adsorption of immunogamma globulin onto various synthetic calcium hydroxyapatite particles

This paper presents data on adsorption of immunogamma globulin (IgG) onto synthetic rodlike calcium hydroxyapatite particles (CaHaps) with various particle lengths and calcium/phosphate (Ca/P) atomic ratios ranging from 1.54 to 1.65 and compares the obtained results to those of acidic (bovine serum albumin, BSA), neutral (myoglobin, MGB), and basic (lysozyme, LSZ) proteins reported before. The effect of electrolyte concentration on IgG adsorption was also examined. The initial rate of IgG adsorption was similar to that of BSA and was slower than that of MGB and LSZ. This fact was interpreted by the difference in the structural stability and molecular weight of these proteins. The isotherms of IgG adsorption onto the CaHap particles were of pseudo-Langmuir type. The saturated amount of adsorbed IgG values ( n s IgG) for the particles with mean particle length less than 70 nm decreased with increasing Ca/P ratio. The adsorption behavior of IgG molecules was very similar to that of basic LSZ, though IgG has zero net charge. The n s IgG value was increased with increased mean particle length of CaHaps; the relationship was less significant than that for BSA but similar to those for MGB and LSZ. The similar adsorption behavior of IgG and LSZ suggested that the F ab parts of IgG molecules preferentially adsorb onto CaHap to provide the reversed Y-shaped conformation of IgG. The change of the adsorption mode of IgG molecules from the reversed Y-shaped conformation to side-on by “spreading” the F c part of IgG molecules onto the particle surface over a longer adsorption time was suggested. The n s IgG value was increased with increasing electrolyte concentration by screening the intra- and intermolecular electrostatic interactions of proteins.

Intrathecal anti-IL-6 antibody and IgG attenuates peripheral nerve injury-induced mechanical allodynia in the rat: possible immune modulation in neuropathic pain

Interleukin-6 (IL-6) is a pleiotrophic cytokine with a diverse range of actions including the modulation of the peripheral and central nervous system. We have previously shown significant IL-6 protein and messenger RNA elevation in rat spinal cord following peripheral nerve injury that results in pain behaviors suggestive of neuropathic pain. These spinal IL-6 levels correlated directly with the mechanical allodynia intensity following nerve injury. In the current study, we sought to determine whether it is possible to attenuate mechanical allodynia and/or alter spinal glial activation resulting from peripheral nerve injury by specific manipulation of IL-6 with neutralizing antibodies or by global immune modulation utilizing immunogamma-globulin (IgG). Effects of peripheral administration of normal goat IgG and intrathecal (i.t.) administration of IL-6 neutralizing antibody, normal goat or normal rat IgG on mechanical allodynia associated with L5 spinal nerve transection were compared. Spinal glial activation was assessed at day 10 post surgery by immunohistochemistry. Low dose (0.01–0.001 μg) goat anti-rat IL-6 i.t. administration ( P=0.025) significantly decreased allodynia and trended towards significance at the higher dose (0.08 μg to 0.008 μg, P=0.062). Low doses (0.01–0.001 μg) i.t. normal goat and rat IgG significantly attenuated mechanical allodynia, but not at higher doses (0.08–0.008 μg; P=0.001 for both goat and rat IgG). Peripherally administered normal goat IgG (30 or 100 mg/kg) did not attenuate mechanical allodynia. Spinal glial activation was unaltered by any treatment. These data provide further evidence for the role of central IL-6 and neuroimmune modulation in the etiology of mechanical allodynia following peripheral nerve injury.

Free-Solvent Model of Osmotic Pressure Revisited: Application to Concentrated IgG Solution under Physiological Conditions

The osmotic pressure measurements of bovine immuno-gamma globulin in phosphate-buffered solution at pH 7.4 and 0.13 M total salt concentration were extended to near saturation concentrations for ambient temperature. The osmotic pressure at the highest measured concentration of 424 g/L was 4.18 psi (28.3 kPa). A free-solvent model, considering solute–solvent interaction in the concentration variable, provided an excellent fit to observed osmotic pressure nonideality at even the highest protein concentration. The calculated mass of hydrated solvent compared with amounts determined from water–17O magnetic resonance for other globular proteins. This model provides an improved correlation to the data over virial equations (truncated to the third term) when only solute–solute interactions are considered. The use of mole fraction as the composition variable was critical in obtaining the excellent fit of the free-solvent model. A combination of the free-solvent correction for the concentration variable coupled with models incorporating solute–solute interaction, such as a virial expansion, will be necessary to generally describe the osmotic pressure of protein solutions for all concentrations.

Surface plasmon resonance studies of immunoreactions utilizing disposable diffraction gratings

The specificity of protein binding between immuno-gamma globulin (IgG) and anti-IgG has been investigated by means of surface plasmon resonance measurements, with a view to determining whether a perspex replica of a holographic diffraction grating can be used efficiently as the momentum-coupling device. The replicas are easy to fabricate, of low cost, and may be useful as disposable sensing heads in a biosensor. The majority of all published work concerning surface-plasmon-based biosensors has detailed the use of prisms as the momentum-coupling devices. Therefore, the relative advantages and disadvantages of both systems are discussed in this paper, including a sensitive optical technique which is beyond the scope of prism geometries.

Detection of Fiji disease virus in sugarcane by ELISA

A direct double antibody sandwich enzyme-linked immunosorbent assay (ELISA) was developed for the detection of Fiji disease virus (FDV) in sugarcane (Saccharum spp. hybrid) cultivars NCo310 and CP44-101. Optimal results were obtained when Dynatech microplates, coated with 2 �g/mL FDV-specific immuno-gamma globulin (IgG) coupled with alkaline phosphatase-lgG conjugate at a concentration of 1/1000, were used. The test could detect FDV in crude extracts (fresh or frozen) of gall and gall-free infected tissues with an end point dilution of 1/5000 and 1/1000, respectively. The FDV antibody showed a high degree of specificity and failed to react with 3 other field-associated sugarcane viruses. When the distribution of FDV within the plant was studied, the highest titre was found in the basal axillary buds decreasing towards the top of the plant and into the roots. However, the apical meristem produced a virus titre significantly higher than any adjacent axillary buds. The ELISA was well suited for large-scale screening programs and its potential was further extended to quarantine work since it could be used to identify the virus in frozen, non-galled tissues.

Chapter 22: Localization patterns for immunoglobulins and albumins in the brain suggest diverse mechanisms for their transport across the blood-brain barrier (BBB)

The blood–brain barrier (BBB) differentially excludes serum γ-globulins and albumin. The mean concentration of immunogammaglobulin (IgG) in cerebrospinal fluid (CSF) of adult humans is about 8 times lower than albumin. In this chapter, immunostaining for IgG and albumin in rat brain sections is compared to determine any differences in the patterns of intracellular vs. extracellular staining. For most animals, selective staining for albumin was far more prevalent than for IgG. Although there were numerous other immunopositive areas, differences seen in staining in of the hippocampus, hypothalamus, and cortex are compared. Generally, patterns of staining included either dark or clear cells on a dark background, or dark cells on a clear background. In areas such as the lateral septum, there were clear (unstained) neurons on a dark background possibly because of diffusion of CSF-borne proteins into the neuropil, yet no uptake of the protein by lateral septa1 neurons. Similarly, neurons in superficial layers of the cerebral cortex were clear on a dark background of neuropil.

The adsorption of different types of monoclonal immunoglobulin on positively and negatively charged polystyrene latices

Electrostatic aspects of the interaction between monoclonal mouse anti-human chorionic gonadotropin immuno gamma globulins and polystyrene latex particles are reported. Adsorption and electrophoresis experiments have been performed as a function of pH, using both negatively and positively charged latices and monoclonal immuno gamma globulins having different isoelectric points. Adsorption isotherms show high affinity character with well-defined plateaus. The plateaus vary with pH, showing a maximum at the isoelectric point of the protein-covered polystyrene particles, rather than at the isoelectric point of the immuno gamma globulin in solution. Since a similar behaviour has been previously reported for bovine serum albumin this observation might be a more general feature in protein adsorption.

Syntheses and applications of water‐soluble reactive polymers for purification and immobilization of biomolecules

Reactive polymers have been prepared by copolymeriz-ing N-isopropyl acrylamide (NIPAM) with N-acryloxy-succinimide (NASI) or glycidyl methacrylate (GMA). The amino groups of ligands could react with the residues of NASI or GMA and the polymers could be precipitated by temperature and/or salinity variation, since they contained the NIPAM residues. As a model, p-aminobenza-midine, a trypsin inhibitor, was attached to the polymers to form water-soluble macroligands, capable of selectively binding trypsin from a trypsin-chymotrypsin solution. After precipitation of the macroligand-trypsin complex, followed by dissociation, approximately 82% trypsin was isolated. The NIPAM-GMA copolymer was also reacted with immunogammaglobulin (IgG) and alkaline phosphatase (AP). It was demonstrated that the IgG bearing polymer was able to bind protein A and the whole complex was precipitable. The reactive polymer was also used for direct immobilization of AP which was active in repeated reactions.

Monoclonal antibodies used in immunocytochemical localization by electron microscopy of carbamoyl phosphate synthetase I in liver from rats fed high-protein diets.

Carbamoyl phosphate synthetase I (CPS-I) is the most abundant protein of rat liver mitochondria. Biochemical measurements in liver homogenates have shown that the liver from rats fed a high-protein diet contains more CPS-I per gram tissue protein than controls. However, there is no information on changes in the intact tissue at the cellular and mitochondrial level. Therefore, monoclonal antibodies to beef liver CPS-I were produced by the hybridoma technique. Four clones, C-241/1A, B, C, and D secreted immunogammaglobulin (IgG) IgG1. Using C-241/C, we measured by electron microscopy immunogold procedures the labeling of CPS-I in mitochondria from liver of rats fed high protein (casein, 50 and 80% of total food intake) diets. CPS-I (expressed as gold particles/micron2 of mitochondrial cross-sectional area) was greater than in mitochondria from control rats (20% casein diet), whether the rats were fed for 1, 6, or 14 months on the high-protein diets. The immunocytochemical measurements shown here demonstrate that the increase in the level of CPS-I in high-protein diets is a reflection of both the larger number of CPS-I molecules per mitochondrial area and the larger proportion of the total hepatocyte volume occupied by mitochondria. Similar measurements were carried out with glutamate dehydrogenase (GDH) using previously characterized monoclonal antibodies. No differences in GDH labeling were found with high-protein diets. Interestingly, when mitochondria from hepatocytes of rats fed a high-protein diet were divided into two subpopulations on the basis of mitochondrial cross-sectional size (i.e., greater or less than 0.7 micron2), the large mitochondria had 1.2 times more CPS-I and 0.8 times less GDH than the small mitochondria nearby.

Transient deficiency of peripheral blood accessory cells in supporting T cell mitogenesis in patients suffering from chronic idiopathic thrombocytopenic purpura after intravenous gammaglobulin treatment.

Mitogenic response of blood lymphocytes to phytohemagglutinin (PHA) and to OKT3 monoclonal antibodies was investigated in 7 patients suffering from chronic idiopathic thrombocytopenic purpura (ITP) before, during and after high-dose intravenous (i.v.) immunogammaglobulin (IgG) infusion. The platelet count rose above the pre-treatment values during infusion therapy in all patients but one. Five out of seven patients presented elevated platelet-associated IgG (PA-IgG) levels at the time of the first infusion; four of these showed an increase in platelet count and a transient reduction or normalization of PA-IgG after IgG infusion. Five out of seven patients showed an impairment of T lymphocyte mitogenic response to PHA and OKT3 before therapy. All patients responded to IgG therapy with a transient deficiency of FcR mediated monocytes (Mo) in supporting T cell mitogenesis induced by both mitogens during and after IgG infusion. This reduced cooperative capability of Mo disappeared at various times after the end of therapy (range 3-12 days). The transient alteration of Mo function, possibly due to a modification in the surface number or in the affinity of Fc-receptors, can explain in part, the increase in platelet count during and after IgSRK infusion.

Stimulation by insulin of cyclic AMP phosphodiesterase. role of glutathione-insulin transhydrogenase

In agreement with other workers, exposure of isolated rat fat cells to insulin shows a dose dependent increase in cyclic AMP phosphodiesterase (PDE) activity. However, when fat cells are pre-exposed to either guinea pig antiserum against insulin, rabbit antiserum against glutathione-insulin transhydrogenase (GIT), or immunogamma globulin against GIT, each antibody preparation totally or almost totally abolished the insulin-dependent increase in PDE activity. In control experiments, appropriate normal (non-immune) sera, normal gamma globulin, or the GIT-antiserum or the GIT-immunogamma globulin which had been previously neutralized with purified rat liver GIT were found to be completely ineffective in abolishing the insulin-dependent PDE activity of fat cells. These results suggest that the GIT-catalyzed sulfhydryl-disulfide inter-change reaction with insulin might be part of the mechanism by which insulin regulates the intracellular cyclic AMP concentration.

Delayed implantation caused by administration of sheep immunogamma globulin against LHRH in the rat.

The effect of the administration of sheep anti-LHRH gamma globulin (anti-LHRH-G) on implantation of fertilized ova was investigated in rats. Daily injections of 1 ml of anti-LHRH-G from Days 1 through 7 of pregnancy uniformly inhibited implantation of fertilized ova on Day 8, but viable sites, though considerably smaller in size than in control rats, became distinguishable on Day 14 in most rats. In some of these rats resorption of fetuses occurred, and others delivered pups 7-8 days after term. When the rats were given anti-LHRH-G from Days 3 through 5, the implantation was delayed by 5 days, but the gestation was not terminated. A single injection of 1 ml of anti-LHRH-G on Day 4 inhibited implantation on Day 8, but injection on Day 3 or 5 did not. The delayed implantation by anti-LHRH-G injected on Day 4 was nullified by concomitant administration of 2 sc injections of 1 mug of LHRH, or a single dose of 1 mug of estradiol. The data indicate that the hypothalamic LHRH is essentail on Day 4 of pregnancy for timely implantation of fertilized ova, probably by maintaining LH and, consequently, estrogen secretion.