[Inflammation and host resistance against bacteria. II.--Isolation of an immunostimulating fraction extracted from mouse inflammatory granuloma, using a new technic of isoelectrofocusing (author's transl)].

Five days following the subcutaneous injection, in the dorsal area of mice, of talc embedded in a calcium phosphate gel the induced granuloma were extracted, pooled and homogenized. After centrifugation, the supernatant was precipitated by 33% SO4(NH4)2. The resulting precipitate (G33) was dialysed, lyophilized and fractionated following preparative isoelectrofocusing either with "Ultrodex" or "Pevikon". This later supporting medium allowed, with a better yield than "Ultrodex" did, the recovery of a fraction with an isoelectric point of 4.9-5.1. Following cross-immunoelectrophoresis with a rabbit mouse-G33 antiserum this fraction was found to contain transferrin and two other proteins of mouse serum. Mice injected IV with 25 microgram of this fraction, when challenged 24 h later, exhibited an increased resistance against Listeria monocytogenes.