SPECIFIC INTERACTION OF ESCHERICHIA-COLI O157 H7-DERIVED SHIGA-LIKE TOXIN-II WITH HUMAN RENAL ENDOTHELIAL-CELLS/

In Escherichia coli O157:H7 foodborne infections of humans, the Shiga- like toxins (SLTs) are thought to be the cause of life-threatening vas cular complications, including acute renal disease known as hemolytic uremic syndrome or HUS. As virtually all E. coli O157:H7 isolates from HUS patients produce SLT-II (vs. SLT-I), the possible preferential in teraction of SLT-II with human renal microvascular endothelial cells ( HRMEC), the putative target of the SLTs in the development of HUS, was studied. SLT-II was 1000 times more potent a cytotoxic agent than SLT -I toward HRMEC. Toxin binding studies shelved that this occurred alth ough HRMEC could bind 10 times more SLT-I than SLT-II. This preferenti al action of SLT-II was specific for renal endothelial cells, as human umbilical vein endothelial cells were almost equally affected by SLT- I and SLT-II.