TERMINAL GLYCAN RESIDUES INCREASED THE ADJUVANT CAPACITY OF THE S-LAYER PROTEIN FROM Lactobacillus kefiri

MALAMUD M; ASSANDRI MH; CARASI P; FREIRE T; SERRADELL MA

Mar del Plata

Congreso; Reunión Anual SAI SAIC SAFIS; 2018

The surface layer (S-layer), a (glyco)-proteinaceous cell envelope constituted by subunits that self-assemble to form a lattice that covers the microbial surface, was ubiquitously found in different bacterial species, including probiotic Lactobacillus kefiri. Recently, we have demonstrated that S-layer proteins from L. kefiri CIDCA 8348 (SLP-8348) injected subcutaneously in combination with incomplete Freund´s adjuvant induced proliferation of CD4+T cells as well as secretion of IFN-γ in draining lymphoid nodes, being glycans involved in that cellular response. In this study, we aim to investigate the adjuvant capacity of the SLPs from L. kefiri strains and to assess the role of the glycosidic moieties in that property. To do that, SLP from two different L. kefiri strains (SLP-8348 and SLP-5818) were removed with 5M LiCl and exhaustively dialyzed against PBS. To test the SLPs adjuvant capacity, one dose (10 µg/mouse) of each SLP or oxidized SLP (SLPOx) in combination with Ovalbumin (OVA at 10 µg/mouse) was subcutaneously injected into the right flank in front of the hind leg on BALB/c mice. After ten days, cells from inguinal lymph nodes were labeled with CFSE and stimulated in vitro with OVA (10 µg/ml) for five days. Proliferation index of CD4+T cells, as well as secretion of IFN-γ, were significantly higher (P