ABSTRACT

The commercial preparation of acellular pertussis vaccine depends on the effective recovery and purification of the antigens pertussis toxin (PT), filamentous haemaglutinin (FHA), and pertactin (PRN) from Bordetella pertussis fermentation. This study describes the recovery of the antigens using an open channel 0.45-μm tangential flow filtration module with optimization of the process parameters of transmembrane pressure, cross flow, and flux. Under the optimized conditions, greater than 98% recovery of FHA and PT was obtained.

(MILLIPORE CORP.)

To keep the disease under control large amounts of PT, FHA, and PRN must be prepared for mass immunization. The first step toward purification is the clarification of the fermentation broth for the recovery and further downstream processing of the antigens. The traditional method available is centrifugation. The scale-up of the process using centrifugation may lead to lower recovery of the antigens and a huge capital investment with low scalability. Therefore, an efficient bioseparation technique that can be easily scaled up with lesser capital investment is necessary. Membrane-based technology for biopharmaceuticals has been widely suggested and used.^5,6 Tangential flow filtration (TFF) technology using an open channel, steam-sterilizable device allows microorganisms to be washed and concentrated in an efficient, rapid manner by using a closed recirculating filtration system, where both the concentrated cell mass and the filtrate can be collected under aseptic conditions. The factors that must be considered for successful scale-up of TFF technology are purity, yield, and reproducibility, for which the process parameters of the TFF must be optimized accurately. This article describes the optimization of the TFF process for high recovery of the acellular pertussis vaccine antigenic components: PT and FHA.