The present study was to investigate the effect of cellulose matrix and oligosaccharide on solid state and morphology characteristics of freeze-dried cationic dimethyldioctadecylammonium (DDA)-based liposomes encapsulating ovalbumin (OVA). The OVA-containing liposomes were protected using cellulose derivative matrix and oligosaccharide. Despite the fact that saccharides are known to preserve protein and lipid membranes during drying, however, collapse structure are often addressed. In other side, cellulose matrix potentially prevents collapsing as it has been widely used for matrix in drug delivery formulations to increase the mass for compact matrices of resultant products. Their solid state characteristics were determined in terms of their crystallinity using X-Ray diffraction (XRD), thermal properties and detection of phase separation using differential scanning calorimetry (DSC). Furthermore, their morphology was observed using scanning electron microscopy and transmission electron microscopy. The study revealed that formulation with either oligosaccharide and cellulose matrix demonstrated a miscible mixture with DDA and soy phosphatidylcholine (SPC) that might construct stable dried liposomal formulation. Phase separation was not observed in formula with combination of oligosaccharide and cellulose matrix where their DSC thermograms showed glass transition indicating amorphous structure and miscible mixture. XRD confirmed the absence of crystal-like properties, demonstrating prevented crystallization. The dry products were porous with spherical liposomes trapped in the matrices, signifying the ease in reconstitution. Furthermore, OVA were well-preserved as its recovery was more than 80%. The preservation of both liposomes and protein antigen were found to be dependent upon the incorporation of both oligosaccharide and cellulose matrix included in the formulation.

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Background: The present study aims to design formulation of liposomes that are well-preserved during freeze-drying. The combination of Hydroxy Propyl Methyl Cellulose (HPMC) as dispersion matrix and lyoprotectants; maltodextrin or mannitol, was employed to prevent aggregation and/or recrystallization. The obtained dry products were investigated in terms of their physical characteristics. Methods: Liposomes were prepared using thin film method and hydrated with the lyoprotectant solution. The formed liposomes were mixed with HPMC gel and freeze-dried. The obtained solid products were characterized using Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM). Results: The DSC thermograms of formulations with maltodextrin were relatively homogenous, yet exhibiting meta-stable properties. In contrast, the formulations using mannitol showed phase separation. These results were confirmed by XRD data, in which formulations with maltodextrin showed no intensive peaks, indicating amorphous solid while the formulations with mannitol exhibited more intensive peaks, indicating the presence of crystalline solids. The SEM images of both maltodextrin and mannitol-containing formulations showed porous matrix with spherical liposomes trapped in the matrices. The SEM images also correspond to the DSC and XRD data, where crystalline solid existed in the mannitol-containing formula. Conclusion: The developed liposomes formulation using combination of HPMC matrix and maltodextrin showed potential in preserving liposomes structure, contrary to those of using mannitol.

BACKGROUND: The development of an oral typhoid fever vaccine need more effective and having high-efficacy in preventing typhoid fever. The use of liposomes as a vaccine vehicle can be formulated to target a specific location or trigger the release of antigens on its target. β-Glucan derived from Candida albicans cell wall as immunoadjuvant can strengthen the immune response and increases the protection against Salmonella Typhi bacterial invasion. AIM: This study aimed to determine the immune response in typhoid fever mice by administering a combination of AdhO36 S. Typhi liposome vaccine with β-Glucan and determine the protectivity to inhibit bacterial colonization in typhoid fever. METHODS: Mice were divided into five groups include negative and positive control also treatment group. IL-12 was evaluated after 4-h immunization while the other (was IL-12, IL-10, Th1 (IL-2), Th2 (IL-4), and the protective test against bacterial invasion) evaluated after 96-h. RESULTS: IL-12 level in the combination of β-Glucan and AdhO36 groups showed significantly lower than infected groups (p = 0.034), whereas IL-10 level significantly increase (p = 0.0009). The percentage of Th-1 (IL-2) cells significantly lower than infected groups (p = 0.000), this also happened on the percentage of Th-2 (IL-4) cells that significantly lower than infected groups (p = 0.018). The protective test toward bacterial invasion showed no bacterial colonization in all tissues intestine, liver, spleen, and mesenteric lymph node. CONCLUSION: The administration of a combination of liposome containing β-Glucan from C. albicans and AdhO36 S. Typhi has a potential effect on cellular and humoral immune response.

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:The present study describes the effect of saccharides and hydroxypropyl methylcellulose (HPMC) matrix on phase behavior of dehydrated cationic dimethyldioctadecylammonium (DDA)-based liposomes. Saccharides such as sucrose, lactose and mannitol,have been reportedpreserve the lipid membranes during drying, whilst HPMC matrix is widely used in solid dispersion to prevent aggregation and/or recrystallization.The study revealed that addition of sucrose and HPMCin the formulation demonstrated a miscible mixture that might construct a stable dried liposomal formulation. DTA data showed that sucrose (5%w/v) and HPMC added to DDA liposomal formulation were relatively more miscible with the mixtures; whereas lactose and mannitol at the same concentration of 5% showed phase separation from the mixtures in the dehydrated state. Furthermore, XRD and SEM analysis exhibited supporting evidences in which formulation using sucrose and lactose showedrelatively less crystalline-forming properties compared to formulation using mannitol. Recrystallization that cause phase separation might trigger leakage and further affect the efficacy of the entrapped drug/antigen. From these data, it might be concluded that a driedliposomal formulation can be prepared in the presence of sucrose (lyoprotectant) that is dispersed in HPMC matrix. The protective mechanism of sucrose (5%w/v) and HPMC matrix is proposed through inhibition of the recrystallization which causes phase separation; indicated by DTA, SEM and XRDdata. The present study revealed prospective advantages of using sucrose and HPMC in development of dried -DDA liposomal formulations.

In the case of infection control, one of our primary concerns is typhoid fever. According to WHO, typhoid prevalence in Indonesia is highly endemic. There is also the problem with the low efficacy of the available vaccine to prevent the disease. Therefore, there is an urgent need to develop a highly effective typhoid vaccine. One of the phases in vaccine development is an exploratory phase, a research-intensive phase of the vaccine development process designed to identify natural or synthetic antigens that might help prevent or treat a disease through computer in silico prediction targets. The vaccines developed through epitope peptide are designed to be safer, more efficacious, and less expensive than traditional vaccines. A thorough understanding of the disease agent, particularly critical epitopes to induce the appropriate immunological reaction, is required to achieve these aims. Mapping epitope sequences or antigenic peptides from pathogenic proteins recognized by B cells and T cells is crucial for vaccine development. Once the epitopes were identified, the polypeptide production could be produced through protein recombinant technology. The polypeptide vaccine, in the end, could be delivered using a liposomal delivery system.

Tuberculosis (TB) is one of the most threatening infectious diseases for Indonesian people. The number of TB patients in 2020 was estimated at 845,000 people with 98,000 deaths. One of the factors that causes difficulty in TB therapy is the lack of adherence and the slow development of new antibiotics when antibiotic resistance appears. The development of nanotechnology-based preparation has the potential to increase the therapeutic effectiveness of the active ingredients, such as in the dry powder inhaler form, which allows the active ingredients to be delivered efficiently to the lungs as the target organs. Keywords: tuberculosis, liposomes, antibiotics, dry powder inhalation