Recombinant glycoproteins as novel antigenic targets for diagnosis of 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

Rosario

Congreso; L Reunión Anual de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular (SAIB 2014); 2014

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 LPS antibodies in combination with bacteriological procedures considerably improves diagnosis of STEC infections. In this work, 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. We demonstrate that using these antigens it is possible to clearly discriminate between STEC O157, O145 and O121 infected patients and healthy children, even at early stages of the disease, as well as to confirm the diagnosis in HUS patients in which the classical diagnostic procedures failed. Additionally, in all the culture-positive HUS patients, the identified serotype was in accordance with the serotype of the isolated strain indicating that these antigens are not only valuable for the diagnosis of HUS but also as a tool for serotyping and guiding the following steps to confirm diagnosis.