| Abstrakt: |
Through methods commonly employed for the recovery of specific soluble substances (polysaccharides) it is possible to obtain from the X 19 strains of the proteus bacillus specific reactive substances which flocculate with antiproteus and typhus serum, (Lim and Kurotchkin,1White,2and Castaneda3). Castaneda3has also shown that suspensions of Mexican Rickettsia similarly treated will yield a specific reacting substance which gives the same precipitation reactions with typhus and antiproteus sera as do the polysaccharides extracted from B. proteus X19. It appears, then, that there is in B. proteus X19and typhus Rickettsiaa common antigenic complex which is responsible for the Weil-Felix reaction. This paper corroborates the above reports and emphasizes White's findings in regard to the dual antigenic nature of the polysaccharidal substance obtainable from the proteus bacillus.Thirty-four samples of human typhus sera have been tested against extracts of B. proteus X19(0–504 strain). All of these were purposely selected from late or convalescent cases. All of them agglutinated the test organism at titers above 1 to 640 at the time the flocculation tests were carried out.Fourteen of these sera were tested against B. proteusextracts made by White's method (hot NaOH extraction with alcohol precipitation) and also against extracts as prepared by Castaneda according to the method of Heidelberger and Avery4which includes extraction in cold antiformin, glacial acetic acid precipitation, precipitation of the supernatant fluid with cold alcohol followed by treatment with ammonium sulfate.Twenty other samples of serum were tested both with White's extract and extracts made according to Castaneda's second method, that of alcohol precipitation of concentrates of 8-day broth cultures of B. proteus X19.Antigen dilutions from 1 to 10 up to 1 to 10,210 were mixed with equal volumes of the typhus serum diluted 1 to 2. |
