Autologous erythrocyte

Epoetin combined with parenteral iron is effective and safe for moderate and severe iron deficiency anemia during pregnancy (26), and iron supplementation is often required (27). The use of epoetin in combination with intravenous iron makes collection of larger numbers of autologous erythrocyte units feasible. However, epoetin does not synergize with G-CSF for the mobilization of peripheral blood progenitor cells in healthy donors (28). 

Studies of the length of survival of transfused erythrocytes in recipient horses have produced variable results. In adult horses, the half-life of Fe-labeled donor erythrocytes was 4 days in three out of six horses and less than 24 h in the other three recipients (Kallfelz et al 1978). This methodology does not permit autologous transfusions as a control. In foals aged 2-5 days the mean half-life of °Cr-labeled donor erythrocytes was 5.5 days compared with 11.7 days for autologous erythrocytes (Smith et al 1992). 

Efficacy Autologous HSC gene therapy and non- myeloablative conditioning in two conditioning in two ADA-SCID patients In both patients, the number of PBLs, serum IgM, IgA and IgG levels, mRNA expression of the ADA vector, intracellular ADA enzymatic activity in PBLs, and erythrocyte enzyme activity indicated a reconstitution of -cell functions, as well as an amelioration of the metabolic pattern. 515130... 

Freshly collected venous blood is anticoagulated with K-EDTA (1 mg/ml blood) or heparin (5 IU/ml heparin sodium) and centrifuged at 3000 rpm for 7 min. The supernatant (plasma) and the buffy coat are removed and discarded. The packed erythrocytes are resuspended in autologous plasma containing 0.25 % human albumin and the haematocrit value is fixed at 10 %. The red blood cells are altered by one or several of the stress factors mentioned above. 

Kannan, R., Labotka, R., and Low, P. S. (1988). Isolation and characterization of the hemichrome-stabilized membrane protein aggregates from sickle erythrocytes. Major site of autologous antibody binding. J. Biol. Chem. 263,13766-13773. 

Turrini, F., Arese, P., Yuan, J., and Low, P. S. (1991). Clustering of integral membrane proteins of the human erythrocyte membrane stimulates autologous IgG binding, complement deposition, and phagocytosis.. Biol. Chern. 266, 23611-23617. 

In one clinical situation, the nature of the autologous carrier may be rather clearly defined this is in drug-induced hemolytic anemia based on immunologic mechanisms. It has been shown that destruction of erythrocytes is due to interaction of IgG antibodies with the red cell membrane after its appreciable penicilloy-lation during therapy with high doeses of penicillin (Levine and Redmond 1967). The antibodies involved were penicilloyl specific but it appeared possible that modified structures of the red cell surface are also contributing to the specificity. If this can be substantiated, the erythrocyte will be definitively implicated as the actual immunogenic carrier. 

Sialidase-treated erythrocytes from rats, unlike the normal erythrocytes, preferentially adhered to mononuclear spleen cells and Kupffer cells of the liver. This recognition manifests itself, both in autologous and homologous systems, by the adhesion of complementary cells in the form of rosettes. This process may be the normal physiological mechanism for removing circulating erythrocytes that have a decreasing proportion of sialic acid residues. 

This model is also supported by the results shown in slide 4 (Fig.2). Normal and HG-PRT deficient erythrocytes were washed and incubated with C-adenine in autologous serum. In normal cells, along with IMP and AMP, the major endproduct was hypoxanthine. In normal cells IMP and AMP were formed in considerable amounts, but in mutant cells only traces of IMP and AMP were recovered. This illustrates the importance of the salvage pathway involving HG-PRT. 

A calorimetric study was done to investigate whether gentamicin affects the metabolism of human blood cells [17]. Venous blood was collected from healthy persons and isolation was carried out for erythrocytes, granulocytes and lymphocytes the cells were then suspended in autologous plasma. Cell suspensions were introduced in the calorimetric vessels for measurement of heat production. Gentamicin was added to the cell suspensions at different concentrations. 

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