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Bacteriotherapy is emerging as a strategic and effective approach to treat infections by providing putatively harmless bacteria (i.e., probiotics) as antagonists to pathogens. Proper delivery of probiotics or their metabolites (i.e., post-biotics) can facilitate their availing of biomaterial encapsulation via innovative manufacturing technologies. This review paper aims to provide the most recent biomaterial-assisted strategies proposed to treat infections or dysbiosis using bacteriotherapy. We revised the encapsulation processes across multiscale biomaterial approaches, which could be ideal for targeting different tissues and suit diverse therapeutic opportunities. Hydrogels, and specifically polysaccharides, are the focus of this review, as they have been reported to better sustain the vitality of the live cells incorporated. Specifically, the approaches used for fabricating hydrogel-based devices with increasing dimensionality (D)—namely, 0D (i.e., particles), 1D (i.e., fibers), 2D (i.e., fiber meshes), and 3D (i.e., scaffolds)—endowed with probiotics, were detailed by describing their advantages and challenges, along with a future overlook in the field. Electrospinning, electrospray, and 3D bioprinting were investigated as new biofabrication methods for probiotic encapsulation within multidimensional matrices. Finally, examples of biomaterial-based systems for cell and possibly post-biotic release were reported.

Antimicrobial resistance poses a growing challenge in respiratory tract diseases like otitis media, often necessitating surgical interventions due to pharmacological treatment limitations. Bacteriotherapy, involving probiotics and/or their bioproducts, emerges as a promising alternative in such a scenario. This study aims to pave the way to middle ear bacteriotherapy by developing an innovative sodium alginate (SA)-based probiotic delivery system using electrospinning and electrospray techniques. Electrospray enabled the precise production of probiotic-laden SA microparticles, demonstrating potential for targeted bacterial delivery. By overcoming challenges due to the SA molecular structure, we successfully electrospun SA-based fiber meshes with poly(ethylene oxide) (PEO) as a support polymer. The rheologic behavior of the probiotic/SA solutions and the morphology of the obtained microparticles and fibers was evaluated, along with the diameter variation over time. The cytocompatibility of the produced microparticles and fibers was assessed using human dermal keratinocytes and their antimicrobial activity was tested against E. coli. The incorporation of probiotic-laden SA microparticles within electrospun SA/PEO fiber meshes finally offered a patch-like structure to be applied on the tympanic membrane or on the outer auditory canal, which could be a versatile and ideally safe treatment strategy in chronic otitis media. This innovative approach holds promise for clinical applications dealing with inflammatory processes, infections and dysbiosis, thus possibly addressing the complex healing process of chronic upper respiratory diseases while mitigating antimicrobial resistance.

Three-dimensional scaffold-based culture has been increasingly gaining influence in oncology as a therapeutic strategy for tumors with a high relapse percentage. This study aims to evaluate electrospun poly(ε-caprolactone) (PCL) and poly(lactic acid) (PLA) scaffolds to create a 3D model of colorectal adenocarcinoma. Specifically, the physico-mechanical and morphological properties of PCL and PLA electrospun fiber meshes collected at different drum velocities, i.e., 500 rpm, 1000 rpm and 2500 rpm, were assessed. Fiber size, mesh porosity, pore size distribution, water contact angle and tensile mechanical properties were investigated. Caco-2 cells were cultured on the produced PCL and PLA scaffolds for 7 days, demonstrating good cell viability and metabolic activity in all the scaffolds. A cross-analysis of the cell–scaffold interactions with morphological, mechanical and surface characterizations of the different electrospun fiber meshes was carried out, showing an opposite trend of cell metabolic activity in PLA and PCL scaffolds regardless of the fiber alignment, which increased in PLA and decreased in PCL. The best samples for Caco-2 cell culture were PCL500 (randomly oriented fibers) and PLA2500 (aligned fibers). Caco-2 cells had the highest metabolic activity in these scaffolds, with Young’s moduli in the range of 8.6–21.9 MPa. PCL500 showed Young’s modulus and strain at break close to those of the large intestine. Advancements in 3D in vitro models of colorectal adenocarcinoma could move forward the development of therapies for this cancer.