Production in vitro of the Toxin of Bacillus anthracis Previously Recognized in vivo

Abstract

SUMMARY: A lethal oedema-producing toxin has been made in vitm in serum cultures of Bacillus anthracis which is identical with the toxin originally recognized in Wiuo. Toxin is produced by the attenuated immunogenic Sterne strain as well as by the virulent N.P. strain. Previous non-recognition of the toxin in cultures was due to its early appearance and rapid disappearance under ordinary growth conditions. A toxin-destroying mechanism was demonstrable in organisms from cultures grown for more than a few hours. Attempts to maintain the toxin concentration or to increase it by addition of various nutrilites to batch culture failed; only by continuous culture have the organisms been kept in their toxigenic growth phase. "races of the toxin appear in cultures in tryptic meat broth; these are increased by the addition of large molecular constituents of serum which appear to play an important role in toxin production.

Effect of aluminum hydroxide adjuvant and formaldehyde in the formulation of rPA anthrax vaccine

“…Several studies have demonstrated the efficacy of PA in vaccines to protect against anthrax intoxication or infection [10][11][12][13]. The importance of anti-PA serum also has been shown in the identification of in vitro correlates of immunity [14][15][16][17] and in passive antibody studies [18][19][20]. This report evaluates the role of the aluminum hydroxide gel adjuvant and the excepient formaldehyde in the formulation of rPA vaccines in the rabbit model using in vitro surrogate markers (the quantitative anti-rPA IgG ELISA and toxin neutralizing antibody (TNA) assay) and efficacy studies.…”

Purification of Factors I and II of the Anthrax Toxin Produced in vivo

“…Anthrax toxin was produced in vitro by Harris-Smith, Smith & Keppie (1958) who used a serum medium, and our colleagues C. B. Thorne and R. E. Strange (private communication) have produced anthrax toxin in a simple medium in vitro. This offered the possibility of fractionating the two factors from a non-protein medium, and hence obtaining purer products than those separated from guinea-pig plasma.…”

The Three Factors of Anthrax Toxin: their Immunogenicity and Lack of Demonstrable Enzymic Activity

“…The specific, lethal and oedema-forming toxin of Bacillus anthracis (Smith, Keppie & Stanley, 1955;Harris-Smith, Smith & Keppie, 1958; Thorne, Molnar & Strange, 1960) consists of three components ; Thorne et al 1960;Stanley & Smith, 1961;Smith & Stanley, 1962). The three factors (I, 11, 111) have been purified.…”