Cytokines involved in the change of antibody specificity induced by LDV (Lactate Deshydrogenase-Elevating Virus)

LILIA A. RETEGUI; JEAN-PAUL COUTELIER; MACARENA A. OTTOBRE SABORIDO; JOSÉ L. APARICIO

Mar del Plata

Congreso; LXI Reunión Anual de La Sociedad Argentina de Investigación Clínica (SAIC) LXIV Reunión Anual de La Sociedad Argentina de Inmunología (SAI) XlVIII Reunión Anual de La Sociedad Argentina de Farmacología Experimental (SAFE) VII NANOMEDAR y V AACyTAL; 2016

Introduction: LDV is a persistent and non pathogenic RNAarterivirus that induces NK, macrophages and B- cell activationin mice. It was found that LDV- infection modified Ab specificityto different antigens, depending on the genetic background of thehost. Objectives: The purpose of this work was to study, throughanti-cytokine auto-vaccination, the cytokines involved in the LDVeffects. Methods: BALB/c, CBA/Ht and C57BL/6 mice were infectedwith 2×107 50% infectious doses of LDV in saline. Subsequently,the animals were inoculated in the footpads, four timesat 2-wk intervals, with 2ìg of IL-15/OVA, IL-23/OVA or IL-17/OVAcomplexes emulsified in Gerbu adjuvant. Ten days after the lastinoculation the animals were bled. Serum lactate dehydrogenase(LD) was determined enzymatically, whereas IL-17 concentrationwas measured by ELISA. The proportion of Ab directed to nativeOVA epitopes was calculated by competition ELISA assays.Results: Vaccination with IL-15/OVA, IL-23/OVA or IL-17/OVAelicited similar titers of anti-OVA Ab in LDV-infected (1/160.000to 1/300.000) and non-infected animals (1/145.000 to 1/300.000).The proportion of native anti-OVA Ab in BALB/c mice vaccinatedwith IL-15/OVA or IL-23/OVA was elevated and similar betweennon-infected (85 and 81%, respectively) and LDV-infected animals(80 and 84%). By contrast, control CBA/Ht mice vaccinated withIL-15/OVA or IL-17/OVA developed low titers of anti native OVAepitopes (56 and 38%, respectively) that increased to 81 and 71%,respectively, in LDV-infected animals. Furthermore, vaccinationwith IL-17/OVA augmented plasmatic IL-17 levels in LDV-infectedanimals in comparison with control (150±12 pg/ml and 23±4 pg/mlP