J. Westdijk et al., QUANTIFICATION OF CELL-ASSOCIATED AND FREE ANTIGENS IN BORDETELLA-PERTUSSIS SUSPENSIONS BY ANTIGEN-BINDING ELISA, Journal of immunoassay, 18(3), 1997, pp. 267-284
In order to achieve batch-to-batch consistency of whole-cell pertussis
vaccines, properties relevant for protection and safety should be cha
racterised. Therefore, ELISAs to quantify pertussis toxin (PT), filame
ntous haemagglutinin (FHA), 92 kD outer membrane protein (92 kD-OMP) a
nd pertactin (PRN) in Bordetella pertussis (B. pertussis) suspensions
were developed. In this paper the influence of the bacterial growth st
age on antigen production and antigen release into the supernatant was
studied for pertussis strains 134, 509 and CS. The levels of cell-ass
ociated and free antigens during growth were strongly strain and antig
en dependent. Because of this, the proportion of cell-associated antig
ens changed during cultivation for all three strains. Substantial amou
nts of PT and PRN were released into the supernatant, while little fre
e FHA and 92 kD-OMP were found. The amount of cell-associated FHA decl
ined rapidly during growth, whereas cell-associated 92 kD-OMP contents
increased. These findings demonstrate that, although antigen exposure
and release differ from strain to strain, the main factor that determ
ines the antigen production and release is the growth phase.