Appropriate biomaterial and controlled size particle are the important component to achieve effective delivery system. Reducing size of the particle is recommended because it can overcome the barriers during cellular uptake. Biomimetic carbonate apatite (CHA) is now considered as candidate for protein delivery because it has high affinity to protein, high biocompatibility and biodegradibility, and increases protein stability. In this study, nano-CHA was prepared and ovalbumin (OVA) protein was incorporated into the CHA particles.

Currently, mucosal infectious diseases are still a very high global health burden, but there are few effective vaccines to prevent mucosal-borne diseases. The development of mucosal vaccines requires the selection of appropriate antigens, delivery system strategies, and adjuvants to increase vaccine efficacy but limited studies have been conducted. The aim of this review is to describe the mucosal immune system, as well as the potential for the development of vaccines and mucosal adjuvants, and their challenges. The study was conducted by applying inclusion criteria for the articles, and a review was conducted by two readers with the agreement. It was known that mucosal vaccination is a potential route to be applied in future preventive efforts through vaccination. However, limited studies have been conducted so far and limited mucosal vaccination has been approved. New technological approaches such as material development involving nano- and micro-patterning are important to intensively open and investigate the potential area of development to provide better vaccination methods.

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Bone infections are a key health challenge with dramatic consequences for affected patients. In dentistry, periodontitis is a medically compromised condition for efficient dental care and bone grafting, the success of which depends on whether the surgical site is infected or not. Present treatments involve antibiotics associated with massive bacterial resistance effects, urging for the development of alternative antibacterial strategies. In this work, we established a safe-by-design bone substitute approach by combining bone-like apatite to peroxide ions close to natural in vivo oxygenated species aimed at fighting pathogens. In parallel, bone-like apatites doped with Ag+ or co-doped Ag+/peroxide were also prepared for comparative purposes. The compounds were thoroughly characterized by chemical titrations, FTIR, XRD, SEM, and EDX analyses. All doped apatites demonstrated significant antibacterial properties toward four major pathogenic bacteria involved in periodontitis and bone infection, namely Porphyromonas gingivalis (P. gingivalis), Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Fusobacterium nucleatum (F. nucleatum), and S. aureus. By way of complementary tests to assess protein adsorption, osteoblast cell adhesion, viability and IC50 values, the samples were also shown to be highly biocompatible. In particular, peroxidated apatite was the safest material tested, with the lowest IC50 value toward osteoblast cells. We then demonstrated the possibility to associate such doped apatites with two biocompatible polymers, namely gelatin and poly(lactic-co-glycolic) acid PLGA, to prepare, respectively, composite 2D membranes and 3D scaffolds. The spatial distribution of the apatite particles and polymers was scrutinized by SEM and µCT analyses, and their relevance to the field of bone regeneration was underlined. Such bio-inspired antibacterial apatite compounds, whether pure or associated with (bio)polymers are thus promising candidates in dentistry and orthopedics while providing an alternative to antibiotherapy.

Buccal mucosae are considered as a site for vaccine delivery since they are relatively abundant with antigen-presenting dendritic cells, mainly Langerhans cells. In this study, we formulated carbonated hydroxy apatite (CHA) with ovalbumin (OVA) (denoted as CHA-OVA), incorporated it into bilayer buccal membrane to form hydrogel films containing CHA-OVA complex for vaccination via buccal mucosae. Ethylcellulose blend with polyethylene glycol 400 were used as impermeable backing layer. Physical properties of all tested buccal membranes were found suitable for mucosal application. In vitro and ex vivo release study showed there was no burst release of OVA found from all tested formula. From the in vivo examination, rabbit buccal mucosae vaccinated by mucoadhesive membranes containing CHA-OVA complex demonstrated mucosal specific antibody induction, represented the potential of CHA as a candidate of needle-free vaccine adjuvant. Future research is awaiting to investigate proper CHA crystallinity in complex with protein against targeted diseases.