STUDIES ON SEROLOGICAL NEUTRALIZATION OF BACTERIAL VIRUSES

II. POLYPHASIC NEUTRALIZATION OF T1 BACTERIOPHAGE

Abstract

The mechanism of neutralization of T1 bacteriophage by the anti-T1 rabbit serum was investigated as to the polyvalency of the virus particle. T1 can develop nearly equal number of plaques on two Shigella, BIII and Shiga strains as well as on Escherichia coli, strain B, but on Shigella KA strain the efficiency of plating was about 0.2.
The rate and final survivors of T1 inactivation by the specific antiserum depend markedly upon the bacterium used for assay. However, the choice of host used in growing the phage stock has no effect. The T1 phage inactivation by the specific antiserum was partially reversible, i.e., a slight reactivation of the neutralized T1 phage occurred on dilution by broth media. The degree of the recovering was estimated to be about 10 to 20 per cent when it was assayed with B or BIII cells, but less than 1 per cent with Shiga cell.
From these findings we concluded that T1 particle has a rather complex antigenic structure in its infectious site, and that the pattern required for invasion to the different host cells may be different each other.