Partial purification and properties of an antibacterial product of peritoneal exudate cell cultures from BCG-infected guinea pigs.

Peritoneal exudates elicited in BCG-infected guinea pigs with caseinate yield cell cultures that have been shown to produce soluble material capable of sterilizing certain bacteria if the cultures are incubated with the specific antigen purified protein derivative or the lectin phytohemagglutinin. This material is now shown to have the following properties: (i) strongly adsorbable to glass; (ii) strongly adsorbable to cation- and not to anion-exchange resins but not elutable with mineral acid or solutions of high ionic strength; (iii) strongly adsorbable to cellulose nitrate membrane filter materials and quantitatively elutable with dilute HCl, providing a convenient method for partial purification; (iv) relatively stable over a wide range of pH and temperature; (v) antagonized by polyanions and by iron ions; (vi) active against the three gram-positive bacilli tested and not against the other organisms tested: (vii) more active in alkaline than in acidic media; and (viii) inactivated by proteolytic enzymes.