INFLAMMATORY RESPONSE MODULATION BY Lactobacillus casei IN AN EXPERIMENTAL MODEL OF PNEUMONIA

HARO CECILIA; VILLENA JULIO; RACEDO SILVIA; AGÜERO GRACIELA; ALVAREZ SUSANA

Tafí del Valle. Tucumán

Jornada; XXII Jornadas Científicas de la Asociación de Biología de Tucumán; 2005

Asociación de Biología de Tucumán

We studied the effect of Lactobacillus casei (Lc) on the inflammatory process induced by Streptococcus pneumoniae (Sp) respiratory infection, in a malnutrition model. Swiss-albino mice were malnourished (M) with protein free diet. Animals were re-nourished for 7d with balanced conventional diet, with (B+Lc) or without (B) Lc supplementation (109 UFC/day). Replete groups, M controls and well-nourished mice (W) were infected intranasally with the pathogen (103 UFC/mouse) in order to obtain an inflammatory state. During 10d post-infection (dpi) we performed: a) Albumin (Ab) concentration and lactate dehidrogenase activity (LDH) in bronchoalveolar lavages (BAL) b) lungs histological examination c) TNFa, IL1b and IL10 concentrations in BAL d) Fibrinogen (fg) and e) Fibrinogen deposition in lungs by immunhistochemistry. Lung injury was significantly higher in M than W, as seen by Ab, LDH and histological examination. M had lower levels of cytokines and fg, and higher fg deposition in lungs than W. B+Lc group showed reduced lung injuries and normal cytokine levels. Parameters studied were higher in B compared with M, but did not reach levels of W. This data suggests that Lc modulates beneficially the inflammatory response against pneumococci in malnourished mice by inducing different cytokine profiles