| 摘要 |
<p>1,214,135. Influenza vaccines. WELLCOME FOUNDATION Ltd. 14 Feb., 1968 [21 Feb., 1967], No. 8232/67. Heading A5B. [Also in Division C6] Viruses of the influenza group, e.g. Myxovirus influencae-A, -B or -C are concentrated and purified by dialysing an aqueous suspension of the virus against water to an extent such that the virus forms a precipitate and separating the precipitated virus fraction from the supernatant solution. The concentration of bivalent metallic cations (e.g. Ca, Mg, Ba and/or Co) in the dialysis water is preferably adjusted to a value from 0.003 to 0.012 M. During dialysis, the conductivity of the suspension is reduced to below 3 x 10<SP>3</SP>Á mho/cm. and the chloride content is reduced to 1.3 mg./ ml. or less. The virus suspension may be an allantoic fluid, obtained from embryonated infected hen's eggs, which has 'been clarified by low speed centrifugation before .the dialysis, which may be carried out in a kidney machine. The separated precipitate may be washed with a solution containing 0.1 M bivalent metallic cations, e.g. Ca; the separated or washed precipitate may be resuspended in a buffer containing triammonium citrate. Influenza vaccines may be obtained by inactivating the viruses, e.g. with formaldehyde, before or after dialysis or using an attenuated strain of virus and presenting the concentrated virus suspensions in a pharmaceutically acceptable vehicle.</p> |
