Journal: Infection and Immunity

Article Title: Immunogenicity and plasmid delivery pathways of non-invasive Lactococcus lactis -vectored mucosal DNA vaccination

doi: 10.1128/iai.00460-25

Figure Lengend Snippet: Plasmid DNA delivery from LL to different cell types. ( A ) Luciferase activity in RAW264.7, THP-1, CMT-93, and ARPE-19 cells co-cultured with LL/pLEC-Nanoluc at the indicated cell-to-bacteria ratios for 20 h. Data are mean ± SEM ( n = 4). * P < 0.05, ** P < 0.01, *** P < 0.001, **** P < 0.0001, ns, not significant by one-way ANOVA with Dunnett’s test (vs ratio 0 for each cell line). ( B ) Fluorescent and phase-contrast images of cells co-cultured with CFSE-labeled LL for 4 h. ( C ) Schematic of time-course experiments. RAW264.7 cells were co-cultured with LL/pLEC-Nanoluc or CFSE-labeled LL; after 2 h, medium was replaced with gentamicin-containing medium, and luciferase activity was measured at the indicated times. ( D ) Time course of luciferase activity in RAW264.7 cells (mean ± SEM, n = 5/time point; the symbols hide some error bars). ( E ) Representative percentage of EGFP-expressing RAW264.7 cells after 20 h co-culture with LL/pLEC-EGFP (mean ± SEM, n = 4). *** P < 0.001 by Student’s t -test. ( F ) Luciferase activity in adhered splenocytes co-cultured with LL/pLEC-Nanoluc for 24 h (mean ± SEM, n = 5). ** P < 0.01 by Mann-Whitney U-test. Cell-to-bacteria ratio was 1:1,000 for panels B, D, and E and 1:10 for panel F.

Article Snippet: The murine colonic epithelial cell line CMT-93 (ATCC) was cultured in low-glucose Dulbecco’s modified Eagle’s medium (DMEM) supplemented with 10% FBS at 37°C in 5% CO 2 .

Techniques: Plasmid Preparation, Luciferase, Activity Assay, Cell Culture, Bacteria, Labeling, Expressing, Co-Culture Assay, MANN-WHITNEY