Mucosal surfaces are tissues lining the respiratory, gastrointestinal, and reproductive tracts. As these tissues are exposed to the external environment, they are the site where many pathogens infiltrate the body. Vaccines eliciting immune responses in mucosal surfaces are, therefore, particularly important to protect the organism from infections.

Adrienne Li, Massachusetts Institute of Technology (MIT), Cambridge, USA, and colleagues used nanoparticles to deliver a vaccine to the mucosal surfaces lining the lungs. The researchers loaded vaccine proteins into interbilayer-crosslinked multilamellar vescicles (ICMVs), namely nanocapsules made of lipid bilayers that are chemically cross-linked one to another through a dithiol. Protected in the nanocapsules, the vaccine proteins persisted in the lungs for a time long enough to generate protective immune cells (memory T lymphocytes).

As these cells were generated not only in the pulmonary mucosa but also in distant mucosal tissues, such as the intestinal and vaginal mucosa, the new nanoparticle-based vaccine protected laboratory animals against infections affecting multiple organs.

• Generation of Effector Memory T Cell-Based Mucosal and Systemic Immunity with Pulmonary Nanoparticle Vaccination,
  A. V. Li, J. J. Moon, W. Abraham, H. Suh, J. Elkhader, M. A. Seidman, M. Yen, E.-J. Im, M. H. Foley, D. H. Barouch, D. J. Irvine,
  Sci. Transl. Med. 2013, 5, 204ra130–204ra130.
  DOI: 10.1126/scitranslmed.3006516