Globulin fractions

Albumin. Investigation iato the safety of bovine plasma for clinical use was undertaken ia the eady 1940s ia anticipation of wartime need (26). Using modem proteia chemistry methods, including electrophoresis and ultracentrifugation, it was shown that most of the human adverse reactions to blood substitutes were caused by the globulin fraction and that albumin was safe for parenteral use. Human albumin is now used extensively as a plasma expander ia many clinical settings. 

Immunoglobulins are associated with the y-globulin fraction of plasma proteins but, as stated earlier, not all immunoglobulins exhibit antibody activity. 

Since antibodies occur in the globulin fraction of serum one predicts that the investigation of the fine structure of serum mucoproteins will become a problem of urgent immunological significance. It is doubtful however whether the carbohydrate group of mucoproteins can influence their immunological specificity.1 ... 

Geitman reported that neomycin did not bind to any of the protein fractions when added to serum but bound to the isolated albumin and globulin fractions. An earlier paper H described the globulin-neomycin complex to be of greater stabil-... 

A later study (45) indicates that cucurbitin from pumpkin has a molecular weight of TT2,000 dal tons that can be electrophoretically separated into subunits of 63,000 and 56,000 dal tons. Reduction of disulfides produces polypeptides of 36,000 and 22,000 dal tons. Globulins from six cucurbits examined chromatographically (46) have molecular weights of 220,000 to 260,000 dal tons that exhibit predominantly 10.4 - 11.2 S values (about 95% of the three globulin fractions). Cucurbitin from Cucumis sativus appears a tetramer of... 

Antibodies are members of a group of proteins known collectively as immunoglobulins. The name is derived from the observation that during electrophoresis of blood plasma the proteins associated with antibody activity migrate with the gamma globulin fraction. 

The table also lists important globulins in blood plasma, with their mass and function. The a- and p-globulins are involved in the transport of lipids (lipoproteins see p. 278), hormones, vitamins, and metal ions. In addition, they provide coagulation factors, protease inhibitors, and the proteins of the complement system (see p. 298). Soluble antibodies (immunoglobulins see p. 300) make up the y-globulin fraction. 

Albumin and Total Globulin Fractions of Blood Derek Watson... 

Antiserum can be raised againsf lymphocyfes or fhymo-cyfes by fhe repealed injection of human cells into an appropriate recipient, usually a horse. The use of such antiserum or the immune globulin fraction derived from it has been used to produce immunosuppression. Although antilymphocytic serum can suppress cellular and often humoral immunity against a variety of tissue graft systems, the responses are variable, particularly from one batch of serum to another. 

During the nineteenth and early twentieth centuries, separation of the proteins was limited to casein and the classical lactalbumin and lacto-globulin fractions of the whey proteins. Subsequent work has resulted in the identification and characterization of numerous proteins from each of these fractions. A classification system of the known proteins in milk developed by the American Dairy Science Association s (ADSA) Committee on Milk Protein Nomenclature, Classification, and Methodology (Eigel et al 1984) is summarized and enlarged to include the minor proteins and enzymes in Table 3.1. 

Albumin- and globulin-type proteins are the major proteins in flaxseed. According to Madhusudhan and Singh (1983), flaxseed albumin comprised 20% of total meal protein. Marcone et al. (1998) reported that the globulin fraction makes up 73.4% of total protein, and the albumin constitutes about 26.6%> of total protein. In contrast, Youle and Huang (1981) reported that 2S proteins accounted for 42%> of the total seed proteins. Sammour (1999) also reported albumin accounted for 40.2%> of the total protein content. 

For clinical purposes serum is preferable to plasma because the fibrinogen band interferes with the reading of globulin fractions. Moreover, it is easier to get serum free from traces of hemoglobin liberated by hemolysis. 

Many proteins are very rapidly denatured so that ideally the fluid should be analyzed immediately. (32-Globulin fractions are partially lost when the serum is kept for some days (03). In work with lipoproteins, refrigeration alters the results (HI, Hla), but preservation in a deep freezer is practical for reference work. 

Mix 0.5 ml globulin fraction with an equal volume of carbonate-bicarbonate buffer, pH 9.3 (4.4 ml 5.3% sodium carbonate plus 100 ml 4.2% sodium bicarbonate). Add 15 mg FITC-Celite and seal to prevent loss of C02. Mix gently for 30 min at room temperature. 

Tuftsin 58, isolated from the protein leukokinin in 1970 by Najjar et al.141) by enzymatic cleavage of a y-globulin fraction, stimulates phagocytosis. 

What is to be emphasized here is the fact that the per cent dose incorporation into the y- plus 0-globulin fractions of the plasma proteins of the hepatectomized rat is not measurably different from that noted in the eviscerated surviving rat. In other words, the concomitant presence of the gastrointestinal tract, pancreas, spleen, and mesentery structures has not grossly altered the qualitative or quantitative pat-... 

After 4 1/2 hours 1.0 ml. blood contained 1.0 x 105 counts/min. Electrophoretic separation of plasma showed 77% of Cu associated with albumin fractions, 1 to 3% in each a-globulin fraction (total 10%), 1 to 3% in each -globulin fraction (total 10%), and about 3% in y-globulins... 

---