| abstract |
A process for the preparation of an immunoglobulin solution containing IgM in concentrated form and suited for intravenous administration, comprising treating an IgM-containing protein fraction obtained by conventional fractionation from blood plasma or serum with beta -propiolactone in an amount such that the ratio of beta -propiolactone to a 5% solution of the IgM-containing proteins is from about 0.05 to 0.15 ml per 100 ml. Advantageously, prior to the treatment with beta -propiolactone the IgM-containing protein fraction is freed of lipids by treatment with colloidal silica gel and with crosslinked dextrans or diethylaminoethyl cellulose. The starting material used is a Cohn fraction III of human blood plasma which has been dissolved in physiological saline solution to a concentration of about 5% protein, the treatment with beta -propiolactone is carried out at about 20 DEG to 37 DEG C. for about 4 to 6 hours until a substantially constant pH of about 8 is obtained, and the solution is thereafter sterile filtered. |