Modification of the erythrocyte membrane by a non-specific lipid transfer protein

The non-specific phospholipid transfer protein purified from bovine liver has been used to modify the phospholipid content and phospholipid composition of the membrane of intact human erythrocytes. Apart from an exchange of phosphatidylcholine between the red cell and PC-containing vesicles, the protein appeared to facilitate net transfer of phosphatidylcholine from the donor vesicles to the erythrocyte and sphingomyelin transfer in the opposite direction. Phosphatidylcholine transfer was accompanied by an equivalent transfer (on a molar basis) of cholesterol. An increase in phosphatidylcholine content in the erythrocyte membrane from 90 to 282 nmol per 100 μl packed cells was observed. Phospholipase C treatment of modified cells showed that all of the phosphatidylcholine which was transferred to the erythrocyte was incorporated in the lipid bilayer. The nonspecific lipid transfer protein used here appeared to be a suitable tool to modify lipid content and composition of the erythrocyte membrane, and possible applications of this approach are discussed

IFCC primary reference procedures for the measurement of catalytic activity concentrations of enzymes at 37 \ub0C. Part 9 : reference procedure for the measurement of catalytic concentration of alkaline phosphatase International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Scientific Division, Committee on Reference Systems of Enzymes (C-RSE) (1))

Abstract This paper is the ninth in a series dealing with reference procedures for the measurement of catalytic activity concentrations of enzymes at 37 \ub0C and the certification of reference preparations. Other parts deal with: Part 1. The concept of reference procedures for the measurement of catalytic activity concentrations of enzymes; Part 2. Reference procedure for the measurement of catalytic concentration of creatine kinase; Part 3. Reference procedure for the measurement of catalytic concentration of lactate dehydrogenase; Part 4. Reference procedure for the measurement of catalytic concentration of alanine aminotransferase; Part 5. Reference procedure for the measurement of catalytic concentration of aspartate aminotransferase; Part 6. Reference procedure for the measurement of catalytic concentration of \u3b3-glutamyltransferase; Part 7. Certification of four reference materials for the determination of enzymatic activity of \u3b3-glutamyltransferase, lactate dehydrogenase, alanine aminotransferase and creatine kinase at 37 \ub0C; Part 8. Reference procedure for the measurement of catalytic concentration of \u3b1-amylase. The procedure described here is derived from the previously described 30 \ub0C IFCC reference method. Differences are tabulated and commented on in Appendix 1