Preparation of a highly purified vaccine against tick-borne encephalitis by continuous flow zonal ultracentrifugation

Abstract

By the use of continuous-flow zonal Ultracentrifugation, a highly purified, inactivated tick-borne encephalitis (TBE) virus vaccine was prepared that contained almost exclusively TBE virus particles. The purity of this preparation was 90- to 100-fold higher than that of a previously used partially purified vaccine. A mean protein content of 3–5 m̈g/ml in the final vaccine represents 20 mouse protective doses₅₀ in a mouse challenge potency test. This high degree of purity resulted in a strong reduction of side reactions observed with the less purified vaccine.