IN VITRO AND IN VIVO ANALYSIS OF IMMUNE MODULATORY POTENTIAL OF DUAL TLR2/7-LIGANDS FOR THE TREATMENT OF ALLERGIC DISEASES

LAIÑO, JONATHAN; WANGORSCH, ANDREA; BLANCO-PÉREZ, FRANK; WOLFHEIMER, SONJA; KRAUSE, MAREN; FLACZYK, ADAM; TSAI, MINDY; GALLI, STEPHEN; VIETHS, STEFAN; SCHEURER, STEPHAN; TODA, MASAKO; SCHÜLKE, STEFAN

Ronneburg

Jornada; Paul-Ehrlich-Institut Retreat on Biomedical Research 2018; 2018

Paul-Ehrlich-Institut

IN VITRO AND IN VIVO ANALYSIS OF IMMUNE MODULATORY POTENTIAL OF DUAL TLR2/7 LIGANDS FOR THE TREATMENT OF ALLERGIC DISEASESLaiño Jonathan1, Wangorsch Andrea1, Blanco Pérez Frank1, Wolfheimer Sonja1, Krause Maren1, Flaczyk Adam1, Tsai Mindy2, Galli Stephen2,3, Vieths Stefan1, Scheurer Stephan1, Toda Masako1, and Schülke Stefan1.1Vice President´s Research Group 1: Molecular Allergology, Paul-Ehrlich-Institut, Langen, Germany2Department of Pathology and the Sean N. Parker Center for Allergy and Asthma Research, Stanford University School of Medicine, Stanford, USA3Department of Microbiology, Stanford University School of Medicine, Stanford, USAE-Mail: Jonathan.Laino@pei.deBackground: Previously we demonstrated that dual TLR2/7 ligands (CL413 & CL531) induced high levels of IL-10 secretion from murine bone-marrow derived dendritic cells (BMDCs), and suppressed IL-5, IL-13, and IL-17A production in BMDC:T cell co-cultures. TLR2 and TLR7 ligands, alone or as mixture, did not have comparable effects in vitro. Aim: To further evaluate the immune modulatory and adjuvant capacity of single and dual TLR2/7 ligands in vitro & in vivo. Methods: Equimolar concentrations of dual TLR2/7 ligands CL401, CL413, and CL531, single TLR7 ligand CL264, and TLR2 ligand Pam2CSK4, were used to evaluate their immune modulatory capacity by stimulation of plasmacytoid dendritic cell-containing Flt-3L cultures, T-cell proliferation in BMDC:T cell co-cultures, and mediator release from RBL-2H3 cells in vitro. Immune modulatory and adjuvant capacity were evaluated by cytokine production in naïve mice, and OVA-specific IgE levels in a mouse model of OVA-induced intestinal allergy. Results: CL413 and CL531 induced secretion of IL-1β, IL-6, and IL-10 from Flt-3L cultures. Here, Pam2CSK4, alone or as mixture, but not CL264, also induced IL-6 synthesis in vitro. CL531 significantly reduced cell proliferation in BMDC:T cell co-cultures compared to single ligands. Upon i.p administration to naïve mice, Pam2CSK4 alone or as mixture, CL413, and CL531 induced IL-1β, IL-6, and TNF-α secretion. Most interestingly, only CL413 induced high amounts of IFN-α in vivo. Vaccination with a mixture of CL531 and OVA, but not with single ligands, significantly suppressed OVA-specific IgE production in mice, and resulted in reduced β-hexosaminidase release by RBL-2H3 cells. Conclusion: Based on the ability to reduce IgE antibodies, decrease mediator release from RBL-2H3 cells, and production of pro-inflammatory cytokines (suggesting a Th1 response) CL413 and CL531 are promising adjuvants for allergy treatment.