Oral vaccination of mice against tetanus with recombinant Lactococcus lactis

Abstract

To determine whether a protective immune response could be elicited by oral delivery of a recombinant bacterial vaccine, tetanus toxin fragment C (TTFC) was expressed constitutively in Lactococcus lactis and administered orally to C57 BL/6 mice. The antibody titers elicited were lower than those following intranasal immunization (a route already known to result in high-level systemic anti-TTFC immune responses) but the protective efficacy was the same order of magnitude. The serum antibody isotypes elicited were predominantly IgG1 and IgG2a. TTFC-specific fecal IgA responses could be detected following oral or intranasal immunization. Chemically killed lactococci administered via the intranasal route were also able to elicit serum antibody responses of similar levels and kinetics to those induced by live bacteria.

An inducible surface presentation system improves cellular immunity against human papillomavirus type 16 E7 antigen in mice after nasal administration with recombinant lactococci

“…In the last decade, several studies have used L. lactis as an antigen delivery vehicle to develop safe, live vaccines (Robinson et al, 1997;Steidler et al, 1998;Chatel et al, 2001;Enouf et al, 2001;Bermú dez-Humarán et al, 2002;Ribeiro et al, 2002;Xin et al, 2003). In these studies, different transcriptional and translational lactococcal signals have been used to express antigens.…”

Lactococcus lactis as a vehicle for the heterologous expression of fungal ribotoxin variants with reduced IgE-binding affinity

“…In addition, Grampositive bacteria not only do not have an outer cell membrane and do not produce endotoxins but rather their peptidoglycan layer appears to exhibit natural immuno-adjuvanticity (Pouwels et al, 1996). This explains why oral vaccination using GRAS Gram-positive bacteria is being developed as a promising approach to the onset of different pathologies, allergies included (Pouwels et al, 1996;Robinson et al, 1997;Maassen et al, 1999;Kirjavainen et al, 1999).…”

“…However, genetically modified versions of this microorganism are still effective in delivering antigens to the mucosal immune system and capable of inducing a local immune response (Robinson et al, 1997;Maassen et al, 1999;AdelPatient et al, 2005;Perez et al, 2005). This seems to happen because L. lactis lacks the ability to multiply in vivo but it can readily be sampled by dendritic cells.…”

Genes involved in obesity: Adipocytes, brain and microflora

“…Finally, probiotics, thanks to their GRAS characteristics associated with their high resistance to the gastric barrier, have been genetically engineered as tools for the delivery of antigens or therapeutic molecules (Robinson et al, 1997;Steidler et al, 2000;Grangette et al, 2001). Nevertheless and obviously, there are many scientific, political and social barriers to allow the introduction of such genetically modified organisms.…”