Antibody Response in the Intestinal Tract of Mice Orally Immunized with Antigen Associated with Liposomes.

Abstract

ABSTRACT. In order to evaluate the usefulness of liposomes, which are stable in acidic solution, bile and pancreatin solution (stable liposomes), as vehicle for oral vaccines, the intestinal IgA antibody responses of mice to liposome-associated antigen after oral administration were examined. The intestinal IgA antibody responses against ganglioside GM1 were detected after the oral immunization of ganglioside GM1-containing stable liposomes. When monophosphoryl lipid A was incorporated into stable liposomes containing ganglioside GM1, further augmentation of IgA responses to ganglioside GM1 was observed. On the other hand, the oral administration with ganglioside GM1 alone was unable to induce any detectable intestinal anti-ganglioside GM1 IgA antibody response. These results suggest that liposomes which are stable in acidic solution, bile, and pancreatin solution would serve effectively as an oral delivery vehicle for inducing mucosal immune responses. -KEY WORDS: liposome, mucosal immunity, oral vaccine.

Mucosal Vaccine Development Based on Liposome Technology

“…Liposomes with DSPC, having a higher transition temperature, were more stable in vitro and likely protected antigen better from degradation in the gastrointestinal tract [49]. It was also found that stable liposomes containing DPPS induced stronger IgA responses compared to formulations without DPPS [34]. Combinations of both DPPC/DMPG and DPPC/PS have been found effective at targeting liposomes to macrophages, though DPPC/DMPG were found more immunogenic than liposomes with DPPC/palmitoyl phosphatidylethanolamine (DPPE) or DPPC/PS.…”

Gastrointestinal Delivery of Baculovirus Displaying Influenza Virus Hemagglutinin Protects Mice against Heterologous H5N1 Infection

“…Thirty mice per each experimental group (n ϭ 30/group) were immunized intragastrically by oral gavage on days 0, 7, and 21 with 200 l containing inactivated or live recombinant baculovirus vaccine at a log 2 HA titer of 8 suspended in phosphate-buffered saline (PBS), pH 7.4, either adjuvanted with 10 g rCTB or unadjvanted. Six mice from each experimental group were sacrificed on days 14, 28, and 42, and serum and intestinal lavage fluids were collected as described previously (32). Briefly, the small intestine from each mouse was cut into 4-to 5-cm pieces and transferred to a glass tube.…”

Protection against experimental Aeromonas salmonicida infection in carp by oral immunisation with bacterial antigen entrapped liposomes

“…problem arises from antigen degradation by gastric acidity and proteolytic enzymes in the intestinal lumen, and extremely large doses are required to achieve satisfactory immune responses. It has been reported that liposomes are an effective carrier of antigen to be processed by antigen-presenting cells, such as macrophages [18], and also that they are an effective antigen-delivery vehicle for the induction of immune response [13,14]. Previously, it was demonstrated that oral administration of liposomes containing BSA effectively induced immune responses in carp [17].…”

“…Liposomes entrapping A. salmonicida were prepared by the following procedure, as described previously [13,14]. DPPC (0.5 mmol), DPPS (0.5 mmol) and Chol (1 mmol), each dissolved in organic solvent, were mixed in a conical flask.…”

“…In particular, liposomes entrapping antigens are protected from low pH and enzymatic attack until they reach the target sites, so that the possibility of liposomes as carriers and adjuvants for developing oral vaccines has attracted considerable interest [12]. Previous studies have demonstrated that liposomes consisting of dipalmitoylphosphatidylcholine (DPPC), dipalmitoylphosphatidylserine (DPPS) and cholesterol (Chol) (1:1:2, molar ratio) are stable in acidic solution, bile, and pancreatin solution [13], and would serve as an effective oral delivery vehicle for inducing mucosal immune responses [14].…”