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Induction of Maternal Immune Activation in Mice at Mid-gestation Stage with Viral Mimic PolyI:C
Published on: March 25, 2016
Non-Viable Lactobacillus Casei Beneficially Modulates Poly I:C Immune Response in Co-Cultures of Human Cells
Elisa Vintiñi1, Marcela Medina
1LARIVENOA, Faculty of Agronomy and Zootechnics, National University of Tucumán, Florentino Ameghino S/N, Tucumán, Argentina.
Background:
Polyinosinic:polycytidylic acid (Poly-IC) has been used as a viral stimulus to mimic in vivo and in vitro infection induced by some viruses.
Objective:
To determine whether non-viable Lactobacillus casei CRL431 (LcM) can modulate the immune response induced by Poly I:C in co-culture models of peripheral blood mononuclear cells (PBMC) and A549 cells.
Methods:
T and NK cell activation was evaluated by flow cytometry and levels of TNF-α, IFN-γ, IL-10, IL-29, and IL-17 by ELISA. Cells in direct contact with A549 (PBMC-A549) and cells with no contact with it (PBMC//A549) were used for this purpose. PBMCs alone and both co-culture systems were stimulated for 24 h with the following stimuli: LPS (10 µg/ml), LcM (106 UFC/ml), Poly I:C (2 µg/ml), Poly I:C+LcM, and LcM (3 h)+Poly I:C. Moreover, unstimulated cells were used as a control.
Results:
Poly I:C and LcM (3 h)+Poly I:C in PBMC-A549 showed a significant increase in the percentage of CD8+ expression (p<0.05). All stimuli induced significant activation from T CD4+, CD8+ cells compared with unstimulated PBMCs in both co-culture cells system. However, activation percentages were higher in direct co-culture. Poly I:C induced a higher level of pro-inflammatory TNF-α and IFN-γ cytokines as well as IL-17 and IL-29 with lower IL-10 levels in both co-culture systems while LcM induced a beneficial pattern of cytokines that would regulate Poly I:C effect.
Conclusion:
This in vitro model allowed us to highlight the potential of LcM as a modulator of anti-viral immune response and suggest its potential use in formulations against RNA respiratory viruses.
Insights
Non-viable Lactobacillus casei CRL431 (LcM) modulates the immune response to Poly I:C, reducing pro-inflammatory cytokines. This suggests LcM
Area of Science:
- Immunology
- Microbiology
- Virology
Background:
- Polyinosinic:polycytidylic acid (Poly-IC) serves as a viral stimulus in research.
- Understanding immune responses to viral stimuli is crucial for developing antiviral strategies.
Purpose of the Study:
- To investigate if non-viable Lactobacillus casei CRL431 (LcM) can modulate Poly I:C-induced immune responses.
- To assess these modulatory effects in co-culture models using peripheral blood mononuclear cells (PBMC) and A549 cells.
Main Methods:
- Co-culture systems (PBMC-A549 and PBMC//A549) were stimulated with LPS, LcM, Poly I:C, or combinations.
- T and NK cell activation was measured by flow cytometry.
- Cytokine levels (TNF-α, IFN-γ, IL-10, IL-29, IL-17) were quantified using ELISA.
Main Results:
- Poly I:C and LcM pre-treatment significantly increased CD8+ expression in direct co-cultures.
- All stimuli activated T cells (CD4+, CD8+), with higher activation in direct co-cultures.
- Poly I:C induced pro-inflammatory cytokines (TNF-α, IFN-γ, IL-17, IL-29) with lower IL-10, while LcM showed a regulatory cytokine pattern.
Conclusions:
- The in vitro model demonstrated LcM's potential to modulate anti-viral immune responses.
- LcM may be beneficial in formulations targeting RNA respiratory viruses.
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