Modulation of Macrophages TLR4-mediated Transcriptional Response by Lacticaseibacillus rhamnosus CRL1505 and Lactiplantibacillus plantarum CRL1506

The aim of this work was to gain insight into the mechanisms involved in the immunomodulatory properties of L. rhamnosus CRL1505 and L. plantarum CRL1506 in the context of TLR4-mediated inflammation, particularly focused on macrophages. Therefore, in vitro studies in murine macrophages were conducted to evaluate the ability of the lactobacilli strains to modulate the transcriptomic response after LPS stimulation. Raw 264.7 mouse macrophage cells (5x10^5 cells/well) were inoculated in 12-well plates and incubated overnight. The culture medium was changed, and macrophages were stimulated with lactobacilli strains CRL1505 or CRL1506 (5x10^7 cells/mL) for 24 h. Macrophages were washed to eliminate lactobacilli and stimulated with 50 ng/mL LPS (InvivoGen, San Diego, USA) for 12 h. Total RNA was extracted using the RNeasy Mini kit (Qiagen, Tokyo, Japan). The RNA labelling and hybridization was performed using the SurePrint G3 Mouse GE 8x60K ver2.0 Microarray from Hokkaido System Science Co., Ltd., Sapporo, Japan. Microarray scanning was performed with the Microarray Scanner from Agilent Technologies, while digitalization was done using Agilent Feature Extraction 10.7.3.1.