CHARACTERIZATION OF THE AGONIST INNATE RESPONSE OF PHARMACEUTICAL PRODUCTS OBTAINED FROM BACTERIAL LYSATES

SOFÍA BEATRIZ SOLER; A. ERREA; BIEDMA, MARINA E.; CECILIA FIGOLI; MARÍA ALEJANDRA BOSCH; JUAN CARLOS LOPEZ; RUMBO MARTIN

Mar del Plata

Congreso; Reunion Conjunta SAIC SAI SAFIS 2018- LXVI Reunión Anual de la Sociedad Argentina de Inmunología; 2018

Sociedad Argentina de Inmunología

Immunostimulation with bacterial lysate-based products has beenworldwide used for the treatment of several recurrent or chronic infectiousdiseases for more than 50 years. However, the way theseproducts may exert their effects is not fully characterized. The InstitutoBiológico Argentino S.A.I.C. (Biol) has developed formulationsbased in glucidolipids extracted from Escherichia coli and Salmonellatyphi: GL01 and GL02 respectively, that are successfully used inArgentina and Latin-American countries since the 60s, indicated toprevent recurrent respiratory infections.Here we analyzed the composition of GL01 and GL02 by FourierTransformed Infrared Spectroscopy (FTIR) and the agonist activityof innate immunity using reporter cell lines.Our FTIR results show that both contain mainly LPS and proteins,however GL02 displays higher molecular complexity than GL01.Both GL01 and GL02 mediate activation of hTLR4 evaluated inHEK-BlueTM hTLR4 cells, 1.9x10-7 μg of KDO of GL02 showsthe same activity than 1.2X10-5 μg of KDO of GL01. Stimulation ofTHP1-XBlue TM-def MyD cells indicates that both products respondto receptors whose signaling is dependent on MyD88. Transfectionof HEK cells with hTLR2 alone or in combination with hTLR1or hTLR6 showed that only S. tyhpi products are able to mediatehTLR2 (and combinations) activation; while hTLR9 or hTLR5 werenot activated by either GL01 or GL02. Activation of ASC-dependentinflammasomes was analysed in THP1 ASC-GFP cells by confocalmicroscopy; 2.37 x10-2 μg of KDO of GL01 activate 1.6 ± 0.5cells/100 total cells and 3.9 x10-1 μg of KDO of GL02 activate 8.6 ±0.6 cells/100 total cells.These results show that GL02 derived from S. typhi exhibits betterstimulation capacity of innate response compared with E. coli derivedproduct under our experimental conditions. These results arerelevant to understand the mechanism of action of immunostimulatorycommercial products, up to now largely unexplained.