Bovine Immunoglobulin G Research Articles

Physiological and Pathological Factors Influencing Bovine Immunoglobulin G1 Concentration in Milk

Bovine immunoglobulin G1 concentration was determined by radial immunodiffusion in 349 milk samples of uninfected quarters, 95 of infected quarters, and 118 blood serum samples from 42 Holstein-Friesian cows taken at days 30, 150, and 270. In lactation, immunoglobulin G1 concentration in milk was not affected by immunoglobulin G1 concentration in blood serum or location of quarters. The immunoglobulin G1 concentrations increased at the end of lactation and in samples collected from cows beyond the third lactation.Uninfected quarters had a mean immunoglobulin G1 concentration of .46 mg/ml. This was less than means from quarters infected by minor or major pathogens. Quarter infection by Staphylococcus aureus resulted in an increase of immunoglobulin G1 concentration in blood serum (9.22 to 11.3 mg/ml). When Corynebacterium bovis was persistent throughout the lactation, immunoglobulin G1 concentration in blood serum was increased (11.26 mg/ml). There was no correlation between somatic cell count and immunoglobulin G1 concentration in uninfected quarters. There was a slight correlation between bovine serum albumin and immunoglobulin G1 concentration in identical quarters (.23). Infection of quarters increased in varying degrees the correlation between immunoglobulin G1 concentration and bovine serum albumin concentration or somatic cell count in milk.

Partial purification and characterization of thyrotropin binding inhibitory immunoglobulins from normal human plasma.

Whole human plasma contains a factor that inhibits the binding of bovine TSH to human thyroid membranes. To determine whether this activity is attributable to the presence of small amounts of immunoglobulin G (IgG) molecules that bind specifically to the thyroid, we have extracted from normal human plasma by a process of selective membrane adsorption a subfraction of IgG that is much more potent in TSH binding inhibition that the starting IgG. The enriched fraction was shown to be IgG by multiple criteria: precipitation in ammonium sulfate, elution by the anion exchange resin DEAE-cellulose, and electrophoresis in sodium dodecyl sulfate-urea polyacrylamide gel. Pretreatment with staphylococcal protein A, with specifically binds IgG, completely removed its activity. Significant TSH binding inhibition was retained under salt conditions, which have been shown to optimize the sensitivity and specificity of the TSH receptor. The enriched fraction was not an antimicrosomal or antithyroglobulin antibody, and did not bind to the TSH label. A similar enriched subfraction of bovine TSH binding inhibitory IgG could be prepared using membranes obtained from kidney and liver, suggesting that the membrane antigen with which it bound was not thyroid specific. These data indicate that in the plasma of individuals presumed to be free of thyroid disease there circulates low concentrations of an IgG which reacts with a thyroid membrane antigen(s). It may be an autoantibody or a normal constituent of plasma with specific binding properties.

Cold Exposure and Absorption of Colostral Immunoglobulins by Neonatal Pigs

To investigate the effect of cold exposure on absorption of colostral immunoglobulins, 56 piglets were weaned at birth and placed in either a thermoneutral (35 C) or cold (21 C) environmental chamber. Thermoneutral piglets had a survival rate of 62% at 48 h, but survival among cold-exposed piglets was only 36% (P less than .10). Cold aid reduced (P less than .01) rectal temperature by more than 6 C after 24 h of exposure. A constant amount of bovine colostrum was administered orally at 4 h after initiation of thermal treatments. Bovine immunoglobulin G1 (IgG1) was readily absorbed and reached a serum level of 17 mg/ml after 24 h. Bovine IgM also was absorbed and increased to approximately 2 mg/ml at 24 h. However, absorption of colostral IgG1 and IgM was not affected by cold exposure. Cold air increased (P less than .05) incidence of diarrhea by over five fold after 72 h, and severity of diarrhea was nearly doubled (P less than .01). Hematocrit was also higher (P less than .05) in cold-exposed piglets. These data demonstrate that a cold stressor sufficient to induce hypothermia does not impair absorption of colostral macromolecules in piglets. However, cold exposure was related to increase incidence and severity of diarrhea.

ウシ免疫グロブリンGの<i>Staphylococcus aureus</i>に対する結合能の比較

乳房炎原因菌の一つであるブドウ球菌に対して凝集能をもつ免疫グロブリンが,乳房炎だけでなく,初乳,常乳および血清中に広く存在している.この菌体凝集反応が抗原抗体反応なのかどうかを知るために,まずIgG1, IgG2とProtein Aとの沈降反応および菌体への結合量を測定した.寒天ゲルを用いた各種沈降反応の結果から,ウシIgG1•IgG2はProtein Aと不溶性複合体を形成する事は否定された.菌体への結合量の測定では,Staphylococcus aureusに対しIgG1<IgG2<IgMの順で結合量が大であった.又この順序は各免疫グロブリンの得られた試料によらず,乳房炎乳でも初乳でも同じであった.

Effects of antibodies to bovine thyroid plasma membranes on in vitro basal and thyroid-stimulating hormone stimulation of bovine thyroid adenylate cyclase.

Antibodies to bovine thyroid plasma membranes were prepared in rabbits by the weekly injection of purified ovine thyroid membranes emulsified in Freund 's complete adjuvant. After immunization, sera and immunoglobulin G (IgG) from two of the seven rabbits significantly increased adenylate cyclase activity in bovine thyroid membranes, while sera and IgG obtained from these two rabbits before immunization were without effect. Although the antibodies to thyroid plasma membranes also contained antibodies against thyroglobulin, these latter antibodies were not responsible for the stimulation of adenylate cyclase activity. Stimulation by these antibodies was biphasic, since maximum stimulation was obtained with about 11 mg protein /ml using serum and 110 jug protein/ml using Igs, while greater amounts had decreasing effects. Serum obtained after immunization noncompetitively inhibited the stimulation by TSH of adenylate cyclase activity. While 66–110 μg protein / ml immunized IgG increased TSH stimulation of ad...

Self-association of bovine immunoglobulin G1.

The self-association properties of bovine serum immunoglobulin G1 and colostral immunoglobulin G1 (IgG1) in 0.32 M-NaCl/0.01 M-Tris/HCl, pH 8.0, were investigated by analysing sedimentation data according to a monomer-dimer association model. The self-association was characterized by an equilibrium constant of 5.3 X 10(4) +/- 3.5 X 10(4) M-1 for serum IgG1 and 1.6 X 10(3) +/- 0.69 X 10(3) M-1 for colostral IgG1. The removal of the Fc portion of IgG1 by pepsin digestion abolished its property of self-aggregation. At high total protein concentrations of serum IgG1, low concentrations of the ostensible trimer species were observed. However, no self-aggregation was evident when 0.14 M-NaCl/0.01 M-sodium phosphate. pH 6.0, was used as a solvent, thus confirming results published previously [Tewari & Mukkur (1975) Immunochemistry 12, 925--930].

Light and immunofluorescent study of the Arthus reaction in the rabbit lung

A localized Arthus reaction was produced in the lung of sensitized rabbits by delivery of antigen into a lower lobe bronchus using a method of selective bronchial catheterization under fluoroscopy. The rabbits were sensitized with bovine immunoglobulin G (B-IgG) in incomplete Freund's adjuvant (IFA) to produce precipitating antibody without classic delayed hypersensitivity. Pulmonary histopathology was studied at intervals following antigen challenge, using light and immunofluorescent microscopy. Gross lesions peripheral to the lower lobe bronchus receiving antigen were found within 12 hr. Subsequent necrosis resulted in a dense scar by 6 wk. Microscopically, early lesions were typified by localized bronchitis, bronchiolitis, alveolitis, and vasculitis with exuberant exudates containing predominantly polymorphonuclear leukocytes. Extensive focal necrosis was present by 72 hr. Immunofluorescent studies revealed the presence of B-IgG, rabbit IgG, and complement (C3) in and around bronchi, bronchioles, alveoli, and vessels. No granulomatous lesions were found, and proliferation of alveolar lining cells was not detected in these studies. Thus, the lung can participate in an acute Arthus reaction following local antigen challenge in systemically sensitized animals. The pathology more closely resembles a necrotizing bacterial pneumonia than an interstitial or hypersensitivity pneumonitis under the conditions of this experimental system. Implications for human disease are speculative.

The controlling effect of carbohydrate in human, rabbit and bovine immunoglobulin G on proteolysis by papin.

About two-thirds of the hexose of human and rabbit immunoglobulin G (IgG) was located in the Fc fragment and one-third in the ;hinge' region of the gamma (heavy) polypeptide chain at the junction of the Fab and Fc fragments. In contrast, bovine IgG contained more hexose in the ;hinge' region than in the Fc fragment. The initial cleavage of susceptible IgG molecules into Fab and Fc fragments by papain under the conditions given by Porter (1959) had reached completion after digestion for 2hr., though bovine IgG was digested somewhat more slowly than human or rabbit IgG. The release of ;hinge' peptides from human and rabbit IgG had also reached completion by 2hr., but was slower from bovine IgG and continued for several hours longer. Since bovine IgG molecules contained on the average a greater amount of hexose in the ;hinge' region, carbohydrate on this part of the gamma-chain may influence not only the initial rate of enzymic hydrolysis into Fab and Fc fragments, but also, and to a greater extent, the rate of further limited hydrolysis of the N-terminal regions of the Fc fragment. The presence of carbohydrate in the ;hinge' region does not appear to account for the resistance of some IgG molecules to papain digestion and of some Fc fragments to N-terminal degradation.