A reexamination of phase IV Bordetella pertussis

Abstract

Eight strains of Bordetella pertussis labeled as "phase IV" and received from different laboratories were examined for their cultural, biochemical, and immunological characteristics in comparison with four phase I strains. Five of the strains possessed cultural and biochemical characteristics agreeing with published information on phase IV B. pertussis. Two of the strains had properties more closely resembling those of Brucella melitensis and one resembled Lophomonas sp.None of the phase IV strains possessed the protective antigen (PA) or the histamine-sensitizing factor (HSF) and they showed little immunological relationship with one another when tested for agglutination by antisera to phase IV except for L-46, L-51, and L-84, which formed a homogeneous serological group. Certain phase I antisera showed some degree of cross-reactivity with phase IV strains but there was much variation between the individual phase IV strains. Conversely the phase IV antisera cross-reacted with phase I organisms.

Cell-Envelope Proteins of Bordetella Pertussis

“…18323, 18334 and 134, and phase-N strain no. 11615 had been used in previous investigations (Aprile, 1972;Aprile and Wardlaw, 1973a and b). A further eight strains were supplied as paired phase-I strains and their corresponding phase-IV variants by Dr Jean Dolby of the Clinical Research Centre, Watford Road, Harrow, Middlesex.…”

“…Phase variation in B.pertussis, although resembling in some ways the smooth to rough variation in Enterobacteriaceae, appears to be considerably more complicated (Aprile, 1972). It may involve changes not only in the serological specificity of the lipopolysaccharide (LPS) but also in growth requirements.…”

Availability and specificity of lipopolysaccharide on the surface of 56 °C heated Bordetella pertussis

“…Previous papers (Aprile 1972;Aprile and Wardlaw 1973) from this laboratory have dealt with various aspects of phase variation in Bordetella pertussis, particular attention having been given to differences in the serological specificity of the lipopolysaccharide (LPS). Using the techniques of immunodiffusion and of passive immune lysis of LPS-coated erythrocytes, a total of six antigenic determinants, designated A, B, C, D, E, and F were detected on LPS from different Bordetella pertussis strains.…”

“…pertussis used and their sources are shown in Table 1. The cultural and serological characteristics of these strains and their PA and HSF content were described previously (Aprile 1972). Phase I strains were grown in Bordet-Gengou medium or in Hornibrook medium.…”

“…The preparation of antisera has been described in previous papers (Aprile and Wardlaw 1973 ;Aprile 1972).…”