Oral administration of Lactococcus lactis-expressing heat shock protein 65 and tandemly repeated IA2P2 prevents type 1 diabetes in NOD mice.

•We constructed two L. lactis expressing recombinant protein HSP65-6IA2P2.•HSP65-6IA2P2 was successfully delivered to intestine mucosa in NOD mice.•L. lactis was proved as the vaccine vector to prevent type 1 diabetes in NOD mice.•Immunomodulatory responses in mice were enhanced by recombinant L. lactis.