2 research outputs found
Self-Assembling Polymer Micelle/Clay Nanodisk/Doxorubicin Hybrid Injectable Gels for Safe and Efficient Focal Treatment of Cancer
The
purpose of this study was to fabricate a safe and effective
doxorubicin (DOX)-delivery system for focal cancer chemotherapy. A
novel biodegradable injectable gel was developed through self-assembly
of poly(d,l-lactide-<i>co</i>-glycolide)-<i>b</i>-poly(ethylene glycol)-<i>b</i>-poly(d,l-lactide-<i>co</i>-glycolide) (PLGA-PEG-PLGA)
copolymer micelles, clay nanodisks (CNDs), and DOX. We discovered
that DOX loaded in the hybrid gels acts as an anticancer drug and
as a building block to organize new gel networks. Accordingly, long-term
sustained release of DOX from hybrid injectable gels without initial
burst release was achieved. Moreover, it was revealed that the DOX
incorporated into gel networks controls its own release profile. This
hybrid injectable gel is a self-controlled drug release system, which
is a novel concept in controlled drug release. Importantly, a single
injection of PLGA-PEG-PLGA/CND/DOX hybrid gel provides long-term sustained
antitumor activity in vivo against human xenograft tumors in mice,
suggesting the potential of hybrid gels as a valuable local DOX-delivery
platform for cancer focal therapy
Enhanced Immunostimulating Activity of Lactobacilli-Mimicking Materials by Controlling Size
The design and synthesis of materials
capable of activating the
immune system in a safe manner is of great interest in immunology
and related fields. Lactobacilli activate the innate immune system
of a host when acting as probiotics. Here, we constructed lactobacilli-mimicking
materials in which polysaccharide–peptidoglycan complexes (PS–PGs)
derived from lactobacilli were covalently conjugated to the surfaces
of polymeric microparticles with a wide variety of sizes, ranging
from 200 nm to 3 μm. The artificial lactobacilli successfully
stimulated macrophages without cytotoxicity. Importantly, we found
that the size of artificial lactobacilli strongly influenced their
immunostimulating activities, and that artificial lactobacilli of
1 μm exhibited 10-fold higher activity than natural lactobacilli.
One major advantage of the artificial lactobacilli is facile control
of size, which cannot be changed in natural lactobacilli. These findings
provide new insights into the design of materials for immunology as
well as the molecular biology of lactobacillus