Annales Immunologiae Hungaricae III. [antikvár]

PRODUCTION AM) CONTROL OF TYPHOID VACCINES* By I. JOÓ Institute for Serobaeteriological Production and Research Human, Budapest We do not propose to discuss in the present lecture details concerning the manifold problems which exist in connection with immunity to, and vaccines against, thypoid (preparation, control, etc.): these questions were exhaustively treated by the Second and Third International Meetings of Biological Standardization [1, 2] and were alsó thoroughly considered in Spaurís monograph [3]. We want to submit the description and results of our own experiments. I. Preparation of vaccines As reported in earlier communications [4, 5], a precipitated thypoid vaccine has been used in Hungary since 1941: it was elaborated by Rauss [6] and contains extract antigén prepared with the modified procedure of Boivin and Mesrobeanu [7]. A great number of inoculations performed in the course of the years 1941 and 1942 enabled Rauss to collect reliable data which demonstrated the high epidemiological value of the vaccine [8, 4], 1.Strains. Apart from the strain S. typhi Ty2, alsó two Hungárián strains (No. 899 and Nova) are used for the preparation of our vaccine. 2.Preparation of extract. The required bacterial suspension is obtained by cultivation in fermentors. Our special method of cultivation was previously described [9, 9a]. After cultivation, the bacterial count of the suspension is photometrically determined with reference to the International Standard for Opacity; this done, 5 per cent of trichloroacetic acid (TCA) is added to the suspension which ensures an extraction at pH 2,0. It should be noted that we treat the whole culture with TCA instead of extracting the washed bacteria. We do this on the evidence of previous experiments in which parallel extractions were performed with whole and washed cultures: their results convinced us that considerably more antigén was obtained when whole cultures were extracted. It is especially in the case of liquid, aerated cultures that the supernate contains much 0 and Vi antigén, and our method enables us to obtain it quantitatively. Since our casein-hydrolyzate médium is devoid of native proteins, no sensitizing substances can gain access to the extract. The process of extraction, performed at 4°C, lasts 20 to 22 hours. After this, the suspension is centrifuged, the yellowish