Serogroup-specific bacterial engineered glycoproteins as novel antigenic targets for diagnosis of Shiga toxin-producing Escherichia coli-associated hemolytic uremic syndrome.

MELLI, LUCIANO J.; CIOCCHINI, ANDRÉS E.; CAILLAVA, ANA JOSEFINA; VOZZA, NICOLAS; CHINEN, ISABEL; RIVAS, MARTA; FELDMAN, MARIO F; UGALDE, JUAN E; COMERCI, DIEGO J; LJM AND AEC COLABORARON IGUALMENTE EN LA REALIZACION DE ESTE TRABAJO

JOURNAL OF CLINICAL MICROBIOLOGY

AMER SOC MICROBIOLOGY

Lugar: Washington; Año: 2014

0095-1137

Human infection with Shiga toxin-producing Escherichia coli (STEC) is a major cause of postdiarrheal hemolytic uremic syndrome (HUS), a life-threatening condition characterized by hemolytic anemia, thrombocytopenia and acute renal failure. E. coli O157:H7 is the dominant STEC serotype associated with HUS worldwide although non-O157 STEC serogroups can cause a similar disease. Detection of anti-O157 E. coli LPS antibodies in combination with stool culture and detection of free fecal Shiga toxin considerably improves diagnosis of STEC infections. In the present report, we have exploited bacterial glycoengineering technology for the development of recombinant glycoproteins consisting of the O157, O145 or O121-polysaccharide attached to a carrier protein as serogroup-specific antigens for the serological diagnosis of STEC-associated HUS. Our results demonstrate that using these antigens in indirect ELISAs (glyco-iELISAs) it is possible to clearly discriminate between STEC O157, O145 and O121 infected patients and healthy children as well as to confirm the diagnosis in HUS patients in which the classical diagnostic procedures failed. Interestingly, a specific IgM response was detected in almost all the analyzed samples indicating that it is possible to detect the infection in early stages of the disease. Additionally, in all the culture-positive HUS patients, the identified serotype by glyco-iELISAs was in accordance with the serotype of the isolated strain, indicating that these antigens are not only valuable for the diagnosis of HUS caused by O157, O145 and O121 serogroups but also for serotyping and guiding the following steps to confirm diagnosis.