title: Nasally administered Lactobacillus rhamnosus accelerate the recovery of humoral immunity in B lymphocyte-deficient malnourished mice.
abstract: The ability of nasally administered Lactobacillus rhamnosus CRL1505 to accelerate the recovery of respiratory B cell-mediated immunity against pneumococcal infection in replete malnourished mice was evaluated. Weaned mice were malnourished after consumption of a protein-free diet for 21 d. Malnourished mice were fed a balanced conventional diet (BCD) for 7 d (BCD group) or a BCD for 7 d with supplemental L. rhamnosus CRL1505 by the nasal route during the last 2 d (BCD+Lr group). Nonreplete malnourished and normal mice were used as the malnourished (MNC) and the well-nourished (WNC) control groups, respectively. Mice were challenged with Streptococcus pneumoniae at the end of each dietary treatment. The immune response was studied before the challenge and at different times postinfection. The MNC mice had less resistance to pneumococcal infection, fewer mature and immature B cells in lung and spleen, and a reduced production of specific antibodies compared with WNC mice. The BCD treatment did not induce a complete normalization of the number B cell populations and antibody amounts. However, the BCD+Lr group had normal numbers of spleen and lung B cells. Moreover, the BCD+Lr mice had a significantly lower susceptibility to S. pneumoniae infection and higher amounts of anti-pneumococcal antibodies. Although further studies are necessary to clarify the effect of malnutrition and nasally administered lactobacilli in other immune cell populations involved in the protection against respiratory pathogens, this work gives evidence of the importance of using nasal priming with probiotics to accelerate the recovery of respiratory immunity in immunocompromised malnourished hosts.
authors.affiliation: Reference Centre for Lactobacilli (CERELA-CONICET), Tucumán, Argentina.
authors.forename: Natalia
authors.initials: N
authors.lastname: Barbieri
authors.forename: Julio
authors.initials: J
authors.lastname: Villena
authors.forename: Matias
authors.initials: M
authors.lastname: Herrera
authors.forename: Susana
authors.initials: S
authors.lastname: Salva
authors.forename: Susana
authors.initials: S
authors.lastname: Alvarez
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology*; D018753:Diet, Protein-Restricted / Q000009:adverse effects; D060467:Disease Resistance; D056724:Immunity, Humoral; D016867:Immunocompromised Host; D052201:Lacticaseibacillus rhamnosus / Q000276:immunology*; D008168:Lung / Q000276:immunology; D008231:Lymphopenia / Q000209:etiology / Q000276:immunology / Q000628:therapy*; D008297:Male; D044342:Malnutrition / Q000178:diet therapy / Q000209:etiology / Q000276:immunology* / Q000503:physiopathology; D051379:Mice; D011008:Pneumococcal Infections / Q000276:immunology / Q000382:microbiology; D019936:Probiotics / Q000008:administration & dosage* / Q000627:therapeutic use; D020545:Respiratory Mucosa / Q000276:immunology* / Q000382:microbiology; D012141:Respiratory Tract Infections / Q000276:immunology / Q000382:microbiology; D013154:Spleen / Q000276:immunology; D013296:Streptococcus pneumoniae / Q000276:immunology / Q000302:isolation & purification
chemical_list: D000907:Antibodies, Bacterial