Immune cells associated to lung metastasis can be modified by the consumption of a probiotic fermented milk.

G. PERDIGON; A. DE MORENO DE LEBLANC; E. MENDEZ UTZ

Buenos Aires

Congreso; Reunión conjunta de sociedades de biociencias; 2017

Lungmetastases (MTS) are common from breast cancers. Immune cells associated to MTScan help tumor cell growth or can response against them. Previous studiesshowed that milk fermented by probiotic Lactobacillus casei CRL431 (PFM)modulated the immune response in mice bearing breast tumor and decreased tumorgrowth and MTS.  The aim of this studywas to evaluate the effect of PFM (administered after tumor surgery) againstimmune cells associated to lung MTS. Female BALB/c mice were injected 4T1 cellsto induce breast tumors and when tumors reached volume near to 0.3  cm3 were surgically removed. After that, micewere divided into 2 groups: one received PFM and the other, milk (M). Healthymice given milk were used as control (C). Mice were euthanized (60d after tumorinjection); the lungs were removed for histology and for the isolation ofimmune cells.  Cells were cultured tomeasure cytokine releases after the in vitro stimulation with 4T1 cells or theywere analysed by flow cytometry to evaluate macrophages and CD4+ and CD8+ Tlymphocytes. PFM administration diminished the nodes in the lungs compared to Mgroup. Cells from lung of PFM group decreased significantly (p<0.05) theconcentration of IL-10, TNFα and IL-6 (71.3±0.3; 363.7±20.2; 766.1100) in culturesupernatants compared to M group (118.4±6.5; 489.4±40; 2899.9±300). Macrophagesdecreased significantly (p<0.05) in PFM group (26.6%±3.6) compared to Mgroup (50.5%±16.8), maintaining percentages similar to C group (27.5%± 2.14).PFM group showed the lowest percentage of IL-10+ macrophages. The percentagesof IL-12+ macrophages and CD8+ cells were similar in both PFM and M group.   The highest percentages for CD4+ andCD4+CD8+ cells were observed in PFM group. Conclusion: Consumption of PFM after tumor surgery decreased lung MTS bymodulating the immune response in the lungs. The decrease of macrophages has akey role in this modulated response, especially through the reduction of IL-10producing macrophages.