title: Identification of Immunopotentiating Lactic Acid Bacteria that Induce Antibody Production by in vitro Stimulated Human Peripheral Blood Mononuclear Cells.
abstract: L-leucyl-L-leucine methyl ester (LLME) is known to remove lysosome-rich cells from human peripheral blood mononuclear cells (PBMCs). To evaluate the immunopotentiating ability of lactic acid bacteria (LAB), we adopted the in vitro stimulation protocol of LLME-treated PBMCs as a model assay system and monitored the level of antibody produced by stimulated PBMCs. The results indicated that several LAB strains have immunopotentiating ability against PBMCs, as evidenced by the enhanced antibody production and increased number of antigen-specific B cells. Next, we identified T cells as the direct target cells of the immunopotentiating LAB strain L32, suggesting that L32 induced antibody production by PBMCs through T-cell activation. Finally, we tested the immunopotentiating ability of ligands for Toll-like receptor 2 (TLR2), which is known to mediate the LAB signal, and observed that both L32 and one of the TLR2 ligands, LTA-BS, induced antigen-specific antibody production by in vitro stimulated PBMC. This suggests that L32 and LTA-BS can be used as an adjuvant for stimulating immune reaction in PBMCs.
authors.affiliation: Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Makiko
authors.initials: M
authors.lastname: Yamashita
authors.affiliation: Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Hitaka
authors.affiliation: Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Himiko
authors.initials: H
authors.lastname: Fujino
authors.affiliation: R&D Center, Nippon Meat Packers, 3-3 Midorigahara, Tsukuba, Ibaraki 300-2646, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsumoto
authors.affiliation: R&D Center, Nippon Meat Packers, 3-3 Midorigahara, Tsukuba, Ibaraki 300-2646, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Hasegawa
authors.affiliation: R&D Center, Nippon Meat Packers, 3-3 Midorigahara, Tsukuba, Ibaraki 300-2646, Japan.
authors.forename: Fumiki
authors.initials: F
authors.lastname: Morimatsu
authors.affiliation: Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Fujiki
authors.affiliation: Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan ; Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Katakura
keywords: Toll-like receptor; human peripheral blood mononuclear cells; immunopotentiating ability; lactic acid bacteria