No abstract

Hydrogels are an attractive class of biomaterials in tissue engineering due to their inherently compatible properties for cell culture. Gelatin methacryloyl (GelMA) has shown significant promise in the fields of tissue engineering and drug delivery, as its physical properties can be precisely tuned depending on the specific application. There is a growing appreciation for the interaction between biomaterials and cells of the immune system with the increasing usage of biomaterials for in vivo applications. Here, we addressed the current lack of information regarding the immune-modulatory properties of photocrosslinked GelMA. We investigated the ability of human mononuclear cells to mount inflammatory responses in the context of a GelMA hydrogel platform. Using lipopolysaccharide to stimulate a pro-inflammatory immune response, we found tumor necrosis factor-α (TNF-α) expression was suppressed in GelMA culture conditions. Our findings have important implications on the future use of GelMA, and potentially similar hydrogels, and highlight the significance of investigating the potential immune-modulatory properties of biomaterials.

A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription. Culturing cells at air-liquid interface (ALI) is essential for creating functional in-vitro models of lung tissue. We present the use of direct-patterned laser-treated hydrophobic paper as an effective semi-permeable membrane, ideal for ALI cell culture. The surface properties of the paper is modified through selective CO2 laserassisted treatment to create a unique porous substrate with hydrophilic regions that regulates fluid diffusion and cell attachment. To select the appropriate model, four promising hydrophobic films were compared with each other in terms of gas permeability and long-term strength in aqueous environment (wetstrength). Among the investigated substrates, parchment paper showed the fastest rate of oxygen permeability (3 times more than conventional transwell cell culture membranes), with the least variation in its dry and wet tensile strength (124 MPa and 58 MPa, remaining unchanged after 7 days of submersion in PBS). The final paper based platform provides an ideal, robust, and inexpensive device for generating monolayers of lung epithelial cells on-chip in a high-throughput fashion for disease modelling and in-vitro drug testing.

The temporal relationship between gatifloxacin administration and the patient's hyperglycemia suggests an iatrogenic cause. Based on our experience and the product labeling, clinicians should be more aware of the blood glucose-altering effects of gatifloxacin.