Immune y-globulin

Human plasma proteins such as serum albumin, fibrinogen or immune -y-globulin may be labelled using Tc04 and a reducing agent, usually The preparation may be... 

West Africans resident in Britain had average y-globulin levels for those in Britain less than two years of 2.2 g/100 ml as compared with 2.0 g/100 ml for those resident two to four years and 1.6 g/100 ml for those resident five to eight years (S3). Specific host factors in which the immune mechanism are implicated was believed to account for the higher levels of y-globulin in American Negroes and Puerto Ricans than in white races (S9). 

Anti-lymphocyte globulin (ALG) has been prepared as an highly purified solution of y-globulins with antilymphocyte activity by immunizing horses with human lymphocytes. It activates complement-mediated destruction of lymphocytes and thus decreases cellular immunity with only a limited effect on humoral immunity. Anti-lymphocyte globulin suppresses delayed type hypersensitivity reactions. It is used for the prevention and treatment of rejection episodes of transplanted organs. It also has some indication for the management of idiopathic aplastic anemia. Adverse effects include pain at the site of injection, erythema, serum sickness and rarely anaphylactic shock and thrombocytopenia. 

Immune globulin (y-globulin, immunoglobulin [Ig] G) is a fraction obtained from the plasma of normal individuals and is rich in antibodies found in whole blood. 

It consists primarily of IgG and contains trace amounts of IgA and IgM. y-Globulin provides the patient with passive immunity and does not require time for the development of an antibody response. It is believed to inhibit viral penetration of host cells, opsonize viral particles, activate complement, and stimulate cell-mediated immunity. 

When injected, azathioprine (Imuran) is rapidly converted to 6-mercaptopurine. The half-life of azathioprine after intravenous injection is 10 to 20 min, and that of 6-mercaptopurine is somewhat longer. The cytotoxic activity of these thiopurines is due to the conversion of mercaptopurine to 6-thiouric acid, a noncarcinostatic metabolite. This action is thought to block the excess synthesis of inosinic acid from its precursors, glutamine and phosphoribosylpyrophosphate. In addition, unlike cyclophosphamide, azathioprine is a potent anti-inflammatory substance that can cause a reduction in the number of monocytes and neutrophils at inflammatory sites. Antibody responses are also inhibited by azathioprine. Studies in humans have shown that azathioprine decreases the y-globulin and antibody levels, thus influencing IgG rather than IgM production. This makes azathioprine an effective immunosuppressant in the early phases of immune responses. It is less effective or completely ineffective in altering either the effector phase or already established reactivities. 

A7. Agnello, V., Winchester, R. J., and Kunkel, H. G., Precipitin reactions of the Clq component of complement with aggregated y-globulin and immune complexes in gel diffusion. Immunology 19, 909-919 (1970). 

Sheep anti-rabbit gammaglobulins for separation step An antibody to rabbit y-globuhns was raised by immunizing sheep with rabbit y-globulins. 

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