A new probotic strain and its potencial effect on the recovery of immunity in malnourished mice

BARBIERI NATALIA; VILLENA JULIO; SALVA SUSANA; HERRERA MATÍAS; ALVAREZ SUSANA

Tafí de Valle. Tucumán

Jornada; XXV Jornadas Científicas de la Asociación de Biología de Tucumán; 2008

Asociación de Biología de Tucumán

We reported that the oral administration of L.casei CRL1505 (Lc05) to adult mice increases resistance to Streptococcus pneumoniae (Sp) infection. The aim of this work was to study whether the administration of Lc05 improves immunity against Sp in immunosuppressed mice. Swiss albino mice were malnourished with after they consumed a protein-free diet for 21d. Then they were fed a balanced conventional diet (BCD) for 7d, or BCD for 7d with Lc05 supplementation (108/sup cell/mouse/d) on the last 5d. At the end of the each treatment, these animals, well-nourished (WNC) and malnourished (MNC) controls were challenged with Sp (105/sup cells/mouse). Lung colonization and bacteremia were higher in MNC than WNC. Treatment with Lc05 significantly decreased pathogen numbers in lungs and it was the only group with negative hemocultures. Lc05 treatment improved the number and the bactericidal activity of blood and bronchoalveolar (BAL) leukocytes. In the Lc05 group levels of serum and BAL anti-Sp IgG were higher than in MNC, whereas BAL anti-Sp IgA was higher than in WNC. Lc05 treatment has a beneficial influence on the recovery of malnourished mice, since it is able to improve innate and adaptative immune response in both the systemic and respiratory compartments.