설사환자로부터 Verotoxin 생산대장균의 분리 및 생물학적 독성

Survey on Isolation and Biological Cytotoxicity of Verotoxin-Producing Escherichia coli Isolated from Diarrheal Patients

The biological characteristics, isolation and/or distibution ratio, cytotoxicity and serological factors were studied for verotoxin-producing Escherichia coli (VTEC) from 145 diarrheal patients in Pusan area. The isolation ratio of VTEC was 8.5% (15 strains of 177 strains), and 5.6% of diarrheal patients were harbouring VTEC. Cytotoxicity for culture supernatants of isolated strains was assayed to Vero cell and HeLa cell monolayers. One strain indicated CD₅₀ at a 10⁶ dilution, uncommonly. A total of 15 isolates produced cytotoxic activity to Vero cell and HeLa cell. When 10² CD₀ units were tested for neutralization with rabbit antiserum against VT1 or VT2, 12 of the 15 isolates were found to secrete VT2, 3 strains in combination with VT1. In addition, 3 isolates secreted only VT1. The serotypes of 15 VTEC were classified by 7 serotypes (O2, O4, O111, O113, O114, O115 and O118).