Lactic acid bacteria efficiently protect human and animal intestinal epithelial and immune cells from enteric virus infection

Abstract

This study aimed to examine the potential antiviral activity of lactic acid bacteria (LAB) using animal and human intestinal and macrophage cell line models of non tumor origin. To this end, LAB strains selected on the basis of previous in vitro trials were co-incubated with cell line monolayers, which were subsequently challenged with rotavirus (RV) and transmissible gastroenteritis virus (TGEV). In order to elucidate the possible mechanism responsible for the antiviral activity, the induction of reactive oxygen species (ROS) release as well as the attachment ability of LAB on the cell lines was investigated. Various strains were found to exhibit moderate to complete monolayer protection against viral RV or TGEV disruption. Highest protection effects were recorded with the known probiotics Lactobacillus rhamnosus GG and Lactobacillus casei Shirota against both RV and TGEV, while notable antiviral activity was also attributed to Enterococcus faecium PCK38, Lactobacillus fermentum ACA-DC179, Lactobacillus pentosus PCA227 and Lactobacillus plantarum PCA236 and PCS22, depending on the cell line and virus combination used. A variable increase (of up to 50%) on the release of NO(-) and H(2)O(2) (ROS) was obtained when LAB strains were co-incubated with the cell lines, but the results were found to be LAB strain and cell line specific, apart from a small number of strains which were able to induce strong ROS release in more than one cell line. In contrast, the ability of the examined LAB strains to attach to the cell line monolayers was LAB strain but not cell line specific. Highest attachment ability was observed with L. plantarum ACA-DC 146, L. paracasei subsp. tolerans ACA-DC 4037 and E. faecium PCD71. Clear indications on the nature of the antiviral effect were evident only in the case of the L. casei Shirota against TGEV and with L. plantarum PCA236 against both RV and TGEV. In the rest of the cases, each interaction was LAB-cell line-virus specific, barring general conclusions. However, it is probable that more than one mechanism is involved in the antiviral effect described here. Further investigations are required to elucidate the underlying mode of action and to develop a cell line model as a system for selection of probiotic strains suited for farm animal applications.

Anti-Infective Activities of Lactobacillus Strains in the Human Intestinal Microbiota: from Probiotics to Gastrointestinal Anti-Infectious Biotherapeutic Agents

“…It has been reported that soluble factors released by L. casei DN-114 001 block the infection of cultured human mucus-secreting HT29-MTX cells by rotavirus RF and WA strains (230). In cultured pig and human epithelial cells infected with rotavirus, Maragkoudakis et al (231) observed that the rotavirus-induced release of reactive oxygen species was decreased in the presence of either L. rhamnosus GG or L. casei Shirota. In a nontransformed porcine jejunum epithelial cell line, the presence of L. rhamnosus GG resulted in a reduced rotavirus-induced IL-6 response (232).…”

Comparison of the Immunomodulatory Effects of Live and Heat-killed Lactobacillus pentosus S-PT84

“…[21][22][23] Heat-killed S-PT84 has also been shown to enhance immune function as well as preventing virus or pathogenic microorganism infection in mice. [18][19][20] In this study, we compared the immunomodulatory effects between live and heat-killed S-PT84.…”

Optimization of Culture Medium for Lactobacillus bulgaricus using Box-Behnken Design

“…And which can increase intestinal beneficial bacteria, balance intestinal environment, improve immunity, and protect human health, etc. Maragkoudakis et al, 2010). The key to the development of the Lactobacillus bulgaricus starter is to obtain high density and high activity culture medium.…”