Intranasal immunization with recombinant Lactococcus lactis secreting murine interleukin-12 enhances antigen-specific Th1 cytokine production.
Interleukin-12 (IL-12), a heterodimeric cytokine, plays an important role in cellular immunity to several bacterial, viral, and parasitic infections and has adjuvant activity when it is codelivered with DNA vaccines. IL-12 has also been used with success in cancer immunotherapy treatments. However, systemic IL-12 therapy has been limited by high levels of toxicity. We describe here inducible expression and secretion of IL-12 in the food-grade lactic acid bacterium Lactococcus lactis. IL-12 was expressed as two separate polypeptides (p35-p40) or as a single recombinant polypeptide (scIL-12). The biological activity of IL-12 produced by the recombinant L. lactis strain was confirmed in vitro by its ability to induce gamma interferon (IFN-gamma) production by mouse splenocytes. Local administration of IL-12-producing strains at the intranasal mucosal surface resulted in IFN-gamma production in mice. The activity was greater with the single polypeptide scIL-12. An antigen-specific cellular response (i.e., secretion of Th1 cytokines, IL-2, and IFN-gamma) elicited by a recombinant L. lactis strain displaying a cell wall-anchored human papillomavirus type 16 E7 antigen was dramatically increased by coadministration with an L. lactis strain secreting IL-12 protein. Our data show that IL-12 is produced and secreted in an active form by L. lactis and that the strategy which we describe can be used to enhance an antigen-specific immune response and to stimulate local mucosal immunity.
Bermúdez-Humarán
Luis G
LG
Unité de Recherches Laitières et de Génétique Appliquée, INRA, Domaine de Vilvert, 78352 Jouy en Josas cedex, France.
Langella
Philippe
P
Cortes-Perez
Naima G
NG
Gruss
Alexandra
A
Tamez-Guerra
Reyes S
RS
Oliveira
Sergio C
SC
Saucedo-Cardenas
Odila
O
Montes de Oca-Luna
Roberto
R
Le Loir
Yves
Y
D000281:Administration, Intranasal; D000818:Animals; D000956:Antigens, Viral / Q000276:immunology; D001483:Base Sequence; D007114:Immunization; D007371:Interferon-gamma / Q000096:biosynthesis; D018664:Interleukin-12 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D007376:Interleukin-2 / Q000096:biosynthesis; D013294:Lactococcus lactis / Q000235:genetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009856:Oncogene Proteins, Viral / Q000276:immunology*; D050725:Papillomavirus E7 Proteins; D011995:Recombination, Genetic; D013154:Spleen / Q000166:cytology / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology*
D000956:Antigens, Viral; D007376:Interleukin-2; D009856:Oncogene Proteins, Viral; D050725:Papillomavirus E7 Proteins; C059731:oncogene protein E7, Human papillomavirus type 16; D018664:Interleukin-12; D007371:Interferon-gamma