On the Preservation of Rickettsia sennetsu by Freeze-drying

Abstract

It was found that Rickettsia sennetsu could be preserved successfully by freezedrying 33% spleen suspension from infected mice in phosphate-glutamate-sucrose buffer (pH 7.0).
Before freeze-drying, LD₅₀ titer of infected mouse spleen for young adult mice was 10^-6.3, and after the procedure, it decreased to 10^-4.5.