Immunogenicity of recombinantLactobacillus casei-expressing F4 (K88) fimbrial adhesin FaeG in conjunction with a heat-labile enterotoxin A (LTAK63) and heat-labile enterotoxin B (LTB) of enterotoxigenicEscherichia colias an oral adjuvant in mice

Abstract

Recombinant Lactobacillus provides a promising platform for the development of vaccines against F4+ ETEC infection.

New Progress Regarding the Use of Lactic Acid Bacteria as Live Delivery Vectors, Treatment of Diseases and Induction of Immune Responses in Different Host Species Focusing on Lactobacillus Species

“…[80]. However, several current studies have point out that immunostimulatory function showed tissue-specific differences among DCs in terms of inducing T helper (Th) cell responses [35, [130][131][132] and recommended that Lactobacillus species are actively concerned in the improvement of adaptive immune responses by programming many aspects of CD4+ T cell differentiation [80]. In additional many Lactobacillus species are microbe-associated molecular pattern (MAMPs) is capable of interacting with epithelial pattern recognition receptors, mainly the Toll-like receptor-2 (TLR2), TLR6 and nod-like receptors which leads to an up-regulation of signaling pathways to modulate the host's immune response [139,140].…”

“…Lactobacillus species are known to influence the immune response in a strain-dependent manner; therefore, they are good candidates for developing innovative oral vectors, comprising good options to reduce the strength of pathogens, meant for mucosal delivery approaches [124,130]. Lately, ever-increasing confirmation supported that Lactobacillus strains expression systems, through expression and delivery of antigens/adjuvant, are hopeful oral vaccine vectors, due to their: efficient delivery of immunogens to the mucosal inductive locations, exceptional safety, reduced antigen degradation and prevention of protein purification On the use of Lactobacillus species as mucosal delivery vectors for therapeutic proteins and DNA vaccines such as expression signals and host strains, for the heterologous expression of therapeutic proteins such as antigens, cytokines and enzymes [133,134].…”

“…(K88) fimbrialadhesinFaeG in conjunction with a heat-labile enterotoxin A (LTAK63) and heat-labile enterotoxin B (LTB) of enterotoxigenic Escherichia coli as an oral adjuvant in mice showed significantly higher levels of FaeG-specific serum IgG and mucosal sIgA, as well as the proliferation of lymphocytes [130][131][132].…”

“…Lately, ever-increasing confirmation supported that Lactobacillus strains expression systems, through expression and delivery of antigens/adjuvant, are hopeful oral vaccine vectors, due to their: efficient delivery of immunogens to the mucosal inductive locations, exceptional safety, reduced antigen degradation and prevention of protein purification On the use of Lactobacillus species as mucosal delivery vectors for therapeutic proteins and DNA vaccines such as expression signals and host strains, for the heterologous expression of therapeutic proteins such as antigens, cytokines and enzymes [133,134]. Resulting recombinant Lactobacillus strains have been tested successfully for their prophylactic and therapeutic effects in different animal models: especially, anti-oxidative Lactobacillus casei, Lactobacillus plantaram and Lactobacillus reuteri strains were constructed and tested in different study models as delivery vehicles for presentation to the mucosa of compounds with pharmaceutical attention, mainly vaccines [35,124,130,135]. The viability of shuttle vector for heterologous protein expression in Lactobacillus casei TISTR1341 was determined that is able to modulate the host response through cloning in pRCEID-LC7.6, the gene encoding the nucleocapsid protein (NP), from the influenza A virus under the control of the homologous promoter from the lactate dehydrogenase gene.…”

An engineered food-grade Lactococcus lactis strain for production and delivery of heat-labile enterotoxin B subunit to mucosal sites

“…A study compared expression efficacy of rLTB in Pichia pastoris with that in E. coli , demonstrating that a higher expression level and adjuvant activity of rLTB could be obtained by using P. pastoris as the expression host [6]. Another study proved that LTB expressed in fusion with antigens in engineered Lactobacillus can significantly enhance the local and systemic immune responses to the antigens [10, 11]. Recently, increasing evidences supported that food-grade L. lactis expression systems, through expression and delivery of antigens/adjuvants, are promising oral vaccine vectors, particularly owing to their outstanding safety, avoidance of protein purification, reduced antigen degradation and efficient delivery of immunogens to the mucosal inductive sites [12, 13].…”