title: Intranasal immunization with liposomes containing IL-2 enhances bacterial polysaccharide antigen-specific pulmonary secretory antibody response.
abstract: Secretory IgA (sIgA) present at mucosal surfaces such as the lungs and intestine plays an important role in resistance to infection occurring at these anatomic sites. Because IL-2 and IL-4 can augment B cell proliferation and Ig production, we investigated possible adjuvant effects of these cytokines on bacterial polysaccharide-specific pulmonary sIgA generation. As shown in previous studies, intranasal immunization with liposomes containing bacterial polysaccharide from Aerobacter levanicum and Pseudomonas aeruginosa resulted in increased numbers of bacterial polysaccharide-specific pulmonary plasma cells and sIgA titers, compared with those found in unimmunized mice. Inclusion of IL-2, but not IL-4, into the intranasally administered liposomes further increased titers of bacterial polysaccharide specific sIgA and pulmonary plasma cells. Intranasal vaccination with liposomes containing bacterial polysaccharide and 10 micrograms/kg IL-2 increased bacterial polysaccharide-specific pulmonary plasma cell numbers by more than 80-fold compared with the response in mice immunized with liposomes containing bacterial polysaccharide, but without IL-2. The percentage of pulmonary plasma cells producing antibody to polysaccharide from A. levanicum rose from 0.14% in mice intranasally immunized with liposomes containing only polysaccharide to 4.1% in animals vaccinated with liposomes containing polysaccharide and IL-2. Intranasal immunization with liposomes containing P. aeruginosa polysaccharide and IL-2 significantly reduced mortality from P. aeruginosa pneumonia. These results demonstrate that IL-2 has potent adjuvant effects on bacterial Ag-specific sIgA production in the lungs when included in intranasally administered liposomes.
authors.affiliation: Department of Medicine, UCLA School of Medicine 90024.
authors.forename: E
authors.initials: E
authors.lastname: Abraham
authors.forename: S
authors.initials: S
authors.lastname: Shah
mesh_terms: D000276:Adjuvants, Immunologic; D000281:Administration, Intranasal; D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis*; D000942:Antigens, Bacterial / Q000008:administration & dosage; D001428:Bacterial Vaccines / Q000008:administration & dosage; D004754:Enterobacter / Q000276:immunology; D005630:Fructans / Q000276:immunology*; D007071:Immunoglobulin A, Secretory / Q000276:immunology; D007376:Interleukin-2 / Q000008:administration & dosage*; D008081:Liposomes / Q000008:administration & dosage; D051379:Mice; D008807:Mice, Inbred BALB C; D011008:Pneumococcal Infections / Q000276:immunology / Q000517:prevention & control*; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D011550:Pseudomonas aeruginosa / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001428:Bacterial Vaccines; D005630:Fructans; D007071:Immunoglobulin A, Secretory; D007376:Interleukin-2; D008081:Liposomes; D011135:Polysaccharides, Bacterial; C072599:levan