title: Mannosylated niosomes as carrier adjuvant system for topical immunization.
abstract: The aim of this study was to develop mannosylated niosomes as a topical vaccine delivery carrier and adjuvant for the induction of both humoral and cellular immunity. Bovine serum albumin (BSA)-loaded niosomes composed of sorbitan monostearate/sorbitan trioleate (Span 60/Span 85), cholesterol and stearylamine as constitutive lipids were prepared by the reverse-phase evaporation method. The niosomes were coated with a modified polysaccharide O-palmitoyl mannan (OPM) to target them to Langerhan's cells, the major antigen presenting cells found in abundance beneath the stratum corneum. Prepared niosomes were characterized in-vitro for their size, shape, entrapment efficiency and ligand binding specificity. The immune stimulating activity was studied by measuring serum IgG titre and its subclasses (IgG2a/IgG1 ratio) following topical application of various niosomal formulations in albino rats. The results were compared with alum-adsorbed BSA following topical application and intramuscular injection. It was observed that niosomal formulations elicited a significantly higher serum IgG titre upon topical application as compared with topically applied alum adsorbed BSA (P<0.05). The serum IgG levels were significantly higher for the mannosylated niosomes as compared with plain uncoated niosomes (P<0.05). All formulations displayed a combined serum IgG2a/IgG1 response, which suggested that the formulations were capable of eliciting both humoral and cellular responses. The study signified the potential of OPM-coated niosomes as a topical vaccine delivery carrier and adjuvant. The proposed system would be simple, stable, and cost effective and might be clinically acceptable.
authors.affiliation: Drug Delivery Research Laboratory, Department of Pharmaceutical Sciences, Dr. Harisingh Gour University, Sagar [M.P.] 470 003, India. sanyogjain@rediffmail.com
authors.forename: Sanyog
authors.initials: S
authors.lastname: Jain
authors.forename: S P
authors.initials: SP
authors.lastname: Vyas
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage* / Q000493:pharmacokinetics; D000287:Administration, Topical; D002626:Chemistry, Pharmaceutical / Q000379:methods; D004337:Drug Carriers / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics; D006801:Humans; D007114:Immunization / Q000379:methods* / Q000639:trends; D007074:Immunoglobulin G / Q000097:blood; D008358:Mannose / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics; D044967:Serum / Q000276:immunology; D013678:Technology, Pharmaceutical / Q000379:methods; D013997:Time Factors
chemical_list: D000276:Adjuvants, Immunologic; D004337:Drug Carriers; D007074:Immunoglobulin G; D008358:Mannose