Influence of Lactobacillus casei administration on hematopoyetical alterations induced by infection in a malnutrition model

SUSANA SALVA; JULIO VILLENA; GRACIELA AGÜERO

Córdoba, Argentina

Congreso; VII Latin American Congress of Immunology; 2005

Sociedad Latinoamericana de Inmunología

The addition of Lactobacillus casei (Lc) to a repletion diet reduces the time required for a normal response against Streptococcus pneumoniae (Spn) infection from 21 to 7days (d) in malnourished mice (MM).Objective:to study the effect of Lc administration on the proliferation and differentiation of bone marrow (BM) cells, during pneumococcal infection in MM and the possible mechanisms involved. Weaned mice were fed a protein-free diet for 21d (MM) and repleted with a balanced diet for 7d without Lc (BD) or with Lc supplementation for 2d (LC). Wellnourished mice (W) were included as control. Mice were challenged intranasally with Spn (103 cells/mouse) and sacrificed on 1,5,10,15d post-infection (dpi). Assays: Differential count of BM cells; BM CD4+,CD8+ and CD19+ cells and serum cytokines (TNFa,IL1,IL4,IL6,IL10). In BM Lc addition was able to induce: a)A significant (p<0.05) increase of the mitotic pool cells, with a peak of myelocytes, (5dpi:W=30±0,8;BD=37±1,6;LC=48±8,3%) and of lymphocytes (5dpi:W=6±0,9;BD=3,5±0,5;LC=7±0,3%). b)Normalization of Peroxidase+cells (1dpi:W=124±4,2;MM=85±2,1; BD=99±3,5;LC=120±4,2%) c)The increase of bGlucuronidase+ and aNaftil Butyrate Sterase+ cells on 10dpi related with BD (bG+:BD=13±0,8;LC=18±2,5-aNBE+:BD=7,0±0,1;LC=10±0,9%) d)The increase of CD19+cells (5dpi:W=1,9±0,2;BD=2,1±0,5;LC=4,1±0,4) e)Normalization of the cytokine profiles in serum with significant (p<0.05) increases of IL4 and IL10 (10dpi:IL4 W=183±18;MM=88±23;BD=112±22;LC=223±21-IL10:W=113±12;MM=54±20; BD=90 ±21;LC=223±24pg/ml). Lc addition to a repletion diet, induced proliferation and differentiation of BM cells during the infection and accelerated the normalization of cytokine profiles in serum