Genetically Engineered Lactococcus lactis Protect against House Dust Mite Allergy in a BALB/c Mouse Model

Abstract

BackgroundMucosal vaccine based on lactic acid bacteria is an attractive concept for the prevention and treatment of allergic diseases, but their mechanisms of action in vivo are poorly understood. Therefore, we sought to investigate how recombinant major dust mite allergen Der p2-expressing Lactococcus lactis as a mucosal vaccine induced the immune tolerance against house dust mite allergy in a mouse model.MethodsThree strains of recombinant L. lactis producing Der p2 in different cell components (extracellular, intracellular and cell wall) were firstly constructed. Their prophylactic potential was evaluated in a Der p2-sensitised mouse model, and immunomodulation properties at the cellular level were determined by measuring cytokine production in vitro.ResultsDer p2 expressed in the different recombinant L. lactis strains was recognized by a polyclonal anti-Der p2 antibody. Oral treatment with the recombinant L. lactis prior sensitization significantly prevented the development of airway inflammation in the Der p2-sensitized mice, as determined by the attenuation of inflammatory cells infiltration in the lung tissues and decrease of Th2 cytokines IL-4 and IL-5 levels in bronchoalveolar lavage. In addition, the serum allergen-specific IgE levels were significantly reduced, and the levels of IL-4 in the spleen and mesenteric lymph nodes cell cultures were also markedly decreased upon allergen stimulation in the mice fed with the recombinant L. lactis strains. These protective effects correlated with a significant up-regulation of regulatory T cells in the mesenteric lymph nodes.ConclusionOral pretreatment with live recombinant L. lactis prevented the development of allergen-induced airway inflammation primarily by the induction of specific mucosal immune tolerance.

Intestinal lysozyme liberates Nod1 ligands from microbes to direct insulin trafficking in pancreatic beta cells

“…L. plantarum was cultured in MRS broth, and L. lactis was cultured in GM17 medium as described. 58 Individual GF mice were gavaged with 100 μL (1 × 10 7 CFU) of each strain, feces were collected after inoculation and subjected to morphological examination under a microscope. Bacterial DNA was extracted from collected feces, and primers (listed in Supplementary Information, Table S1) specific for L. lactis and L. plantarum were used for PCR identification.…”

Lactococcus lactis As a Versatile Vehicle for Tolerogenic Immunotherapy

“…With respect to inhaled allergens, the modulation of allergic immune responses to the major dust mite allergen Der p2 by recombinant L. lactis has recently been described ( 103 ).…”

Lactic acid bacteria: reviewing the potential of a promising delivery live vector for biomedical purposes

“…Some studies have combined the bacterial effect with an expressed antigen either for food hypersensitivity or aero-allergens. The administration of L. lactis displaying the recombinant allergen intracellularly, in the extracellular space or cell wall-anchored show its capacity to modulate the Th2-based specific antibody responses, in the case of the allergen Ara h 2 against peanut allergic [ 93 ] and the Der p2 allergen against the dust mite allergy [ 94 ]. In the second study, the authors also observed a diminution in the cellular infiltration and inflammatory response.…”