Fig. 2.
The Rickettsia pso is the determinant of Weil–Felix serology. (A) Diagram of the pso in pathogenic Rickettsia. Arrowheads indicate transposon insertion sites. (B) Silver-stained polyacrylamide gel of affinity-purified LPS from R. conorii wild type (WT) or the pso variants HK2 and HK15. (C) Immunoblot of R. conorii LPS with R. conorii (α-RcHu) or O. tsutsugamushi (α-OtHu) convalescent human sera. (D) Rabbit antisera raised against affinity-purified LPS from R. conorii wild type (α-LPSWT) or the pso variants HK2 (α-LPSHK2) and HK15 (α-LPSHK15) were examined for antibodies against WT, HK2, and HK15 LPS and compared with naive rabbit serum. (E) Silver-stained polyacrylamide gel of affinity-purified LPS from P. vulgaris OX2 and OX19 and P. mirabilis OXK. (F) Immunoblot of P. vulgaris OX2 and OX19 and P. mirabilis OXK LPS with α-RcHu or α-OtHu. (G) α-LPSWT, α-LPSHK2, or α-LPSHK15 was examined for antibodies cross-reactive against P. vulgaris OX2 and OX19 and P. mirabilis OXK LPS.