Effect of different routes of administration of Lactobacillus rhamnosus CRL1505 on emergency granulopoiesis and respiratory innate immune response in protein-malnourished mice

SALVA, SUSANA; HERRERA, MATÍAS; VILLENA, JULIO; BARBIERI, NATALIA; MARRANZINO, GABRIELA; ALVAREZ, SUSANA

Los Cocos, Córdoba

Congreso; LXI Reunión Anual de la Sociedad Argentina de Inmunología (SAI); 2013

Sociedad Argentina de Inmunología

This work studied the effect of protein malnutrition on the hemato-immune response to the challenge with Streptococcus pneumoniae (Sp) and evaluated whether the dietary recovery with supplemental probiotics has a beneficial effect in that response. Malnourished mice received balanced conventional diet (BD) during 7d (B group) or BD with oral Lactobacillus rhamnosus CRL1505 (Lr) supplementation (108 cells/mouse/d) during last 5d of the treatment (LrO group); or nasal Lr supplementation during last 2d of the treatment (LrN group). On d8, these groups, well-nourished (WC) and malnourished (MC) controls, were infected nasally with Sp (105 cells/mouse). Leucocytes numbers and phagocytes activity, Gr1 and CD34 expression and the levels of IL-6, TNF-α, IL-1β, GM-CSF, IL-10 and IFN-γ were studied in broncho-alveolar lavages (BAL) and blood. In addition, leucocytes numbers and expression of Gr-1, CD34, CXCL12, GM-CSF, IL-1β and SCF were analyzed in bone marrow (BM). Protein-malnutrition significantly impaired innate immunity and emergency myelopoiesis in response to pneumococcal infection, since reduced recruitment and activity of neutrophils were detected in lungs. Repletion of malnourished mice with LrO or LrN significantly accelerated granulopoiesis recovery and improved innate immunity. After infection, the treatment with LrO or LrN improves emergency granulopoiesis, showing behavior myeloid cell populations in BM similar to WC. In addition, this effect achieved by LrO and LrN treatments is related to its capacity to differentially up-regulate hematopoietic grow factors in the BM, showing mRNA levels of CXCL12 that were significantly higher than WNC group. Besides, the levels of CXCL12 were significantly higher in LrO mice when compared with the LrN group. The results show that the protective effect of immunobiotics vary according to the route of administration, being the oral route the most effective to improve emergency granulopoiesis in malnourished mice. The dietary recovery of malnourished mice with supplemental L. rhamnosus CRL1505 improves emergency granulopoiesis and the CXCR4/CXCR12 signaling is involved in this effect.