Heat‐Killed Lactic Acid Bacteria Enhance Immunomodulatory Potential by Skewing the Immune Response toward Th1 Polarization

作者：Chu‐Chyn Ou, Shiao-Lin Lin, Jaw‐Ji Tsai, Meei‐Yn Lin · 发表于：Journal of Food Science · 年份：2011 · DOI：10.1111/j.1750-3841.2011.02161.x · 被引用次数：139 · 研究领域：Probiotics and Fermented Foods、Antimicrobial Peptides and Activities、Viral gastroenteritis research and epidemiology

Heat-killed lactic acid bacteria not only possess immunomodulatory functions but also provide the advantages of longer product shelf life, easier storage, and more convenient transportation. To establish appropriate heat treatments for the industrial preparation of probiotics with immunomodulatory effects, 4 different heat treatments were used to kill 11 strains of lactic acid bacteria. Comparisons among the strains and with viable forms were carried out in terms of immunomodulatory activity and adhesion to Caco-2 cells. Field-emission scanning electron microscope (FE-SEM) was employed to observe morphological changes in bacteria after heating. Among the 11 viable strains, Lactobacillus gasseri AI-88 was the strongest inducer of interferon-gamma (IFN)-γ and interleukin (IL)-12p70 production. However, after heat treatments its stimulatory ability was attenuated. Heat-killed Enterococcus faecalis YM-73 and Lactobacillus salivarius AP-32 strains showed enhanced stimulation of IFN-γ and IL-12p70 secretion and coincidental decrease in IL-13 production. The adhesion of lactic acid bacteria to Caco-2 cells decreased with increases in temperature. However, heat exposure did not influence immunomodulatory activity. With rising temperature, roughness and unevenness of bacterial cell surfaces increased significantly. The results indicated that heat-killed E. faecalis YM-73 and L. salivarius AP-32 have immunomodulatory ability via increased Th1-associated cytokines and reduced Th2-associ...